This document discusses drilling fluids, including their types, functions, properties, and additives. It covers the main types of drilling fluids as water-based and oil-based, and their key functions such as removing cuttings from the wellbore, maintaining wellbore pressure and stability, lubricating and cooling the drill bit. The most common additives are described, including weighting materials to increase mud density, viscosifiers to suspend cuttings and materials, and other additives that control filtration, rheology, alkalinity and other properties. Selection of the appropriate drilling fluid depends on formation data and requirements for each well section.
The document discusses drilling fluids or mud, which are fluids circulated during drilling operations. There are several types of drilling fluids including water-based, oil-based, foam-based, and synthetic-based fluids. Drilling fluids serve various important functions including removing cuttings from the well, controlling formation pressure, maintaining wellbore stability, minimizing damage to the reservoir, and cooling and lubricating the drill bit. The appropriate type of drilling fluid depends on factors like the desired performance, environmental considerations, safety, cost, and availability. Water-based and oil/synthetic-based fluids are described in more detail. The document also outlines various properties and tests used to analyze the characteristics of drilling fluids.
This document provides an overview of drilling fluids and their role in drilling operations. It discusses the components and properties of drilling fluids, including continuous and dispersed phases as well as additives. The types of drilling fluids are described, including water-based muds, oil-based muds, gases, and gas-liquid mixtures. The key functions of drilling fluids to support drilling operations are also outlined. The document concludes with discussions of pressure terminologies and examples of calculations related to drilling fluid properties and components.
Drilling fluids are absolutely essential during the drilling process and considered the primary well control.
Know more now about such a very important component of the drilling process.
This document discusses sustainable drilling fluid solutions. It begins with basic terminology used in drilling fluids like mud types, additives, and functions of mud. Water-based mud and oil-based mud are compared, noting that WBM is less toxic and can meet environmental issues but is not stable above 400°F, while OBM is stable above 400°F but more toxic. New developments in bio-polymers are discussed that can viscosify drilling fluids with less toxicity and better stability. In conclusion, water-based muds with bio-polymers are the most sustainable option while also addressing environmental concerns related to drilling fluids.
The document discusses various drilling problems that can occur such as pipe sticking, loss of circulation, hole deviation, and more. It describes the causes and solutions for different types of pipe sticking problems including differential pressure sticking and mechanical sticking due to cuttings accumulation, borehole instability, or key seating. The document also covers loss of circulation issues and explains common lost circulation zones and causes. Planning and understanding potential problems is key to successfully reaching the target zone.
After drilling is completed, wells undergo completion procedures to prepare them for production. This involves setting production casing and cementing it through the target zone. Tubing is run inside the casing with a packer to isolate the production zone. A Christmas tree is installed to control flow. Completion types include open hole, liners, and perforated casing. Perforating creates holes through casing into the formation. Some formations require stimulation like acidizing to improve permeability or fracturing to create conductive fractures held open by proppant. This increases flow into the wellbore.
Bullheading is a common non-circulating method for killing live wells prior to workovers. It involves pumping kill fluid into the tubing to displace produced fluids back into the formation. A bullheading schedule is generated using formation pressure, desired overbalance, fracture pressure, tubing specifications, and pump data to safely control pumping pressures within the initial and final maximum pressures. The schedule provides checkpoints to monitor pumping pressure and volume throughout the operation. Special attention should be paid to any increases in casing pressure which could indicate downhole issues.
The document discusses drilling fluids or mud, which are fluids circulated during drilling operations. There are several types of drilling fluids including water-based, oil-based, foam-based, and synthetic-based fluids. Drilling fluids serve various important functions including removing cuttings from the well, controlling formation pressure, maintaining wellbore stability, minimizing damage to the reservoir, and cooling and lubricating the drill bit. The appropriate type of drilling fluid depends on factors like the desired performance, environmental considerations, safety, cost, and availability. Water-based and oil/synthetic-based fluids are described in more detail. The document also outlines various properties and tests used to analyze the characteristics of drilling fluids.
This document provides an overview of drilling fluids and their role in drilling operations. It discusses the components and properties of drilling fluids, including continuous and dispersed phases as well as additives. The types of drilling fluids are described, including water-based muds, oil-based muds, gases, and gas-liquid mixtures. The key functions of drilling fluids to support drilling operations are also outlined. The document concludes with discussions of pressure terminologies and examples of calculations related to drilling fluid properties and components.
Drilling fluids are absolutely essential during the drilling process and considered the primary well control.
Know more now about such a very important component of the drilling process.
This document discusses sustainable drilling fluid solutions. It begins with basic terminology used in drilling fluids like mud types, additives, and functions of mud. Water-based mud and oil-based mud are compared, noting that WBM is less toxic and can meet environmental issues but is not stable above 400°F, while OBM is stable above 400°F but more toxic. New developments in bio-polymers are discussed that can viscosify drilling fluids with less toxicity and better stability. In conclusion, water-based muds with bio-polymers are the most sustainable option while also addressing environmental concerns related to drilling fluids.
The document discusses various drilling problems that can occur such as pipe sticking, loss of circulation, hole deviation, and more. It describes the causes and solutions for different types of pipe sticking problems including differential pressure sticking and mechanical sticking due to cuttings accumulation, borehole instability, or key seating. The document also covers loss of circulation issues and explains common lost circulation zones and causes. Planning and understanding potential problems is key to successfully reaching the target zone.
After drilling is completed, wells undergo completion procedures to prepare them for production. This involves setting production casing and cementing it through the target zone. Tubing is run inside the casing with a packer to isolate the production zone. A Christmas tree is installed to control flow. Completion types include open hole, liners, and perforated casing. Perforating creates holes through casing into the formation. Some formations require stimulation like acidizing to improve permeability or fracturing to create conductive fractures held open by proppant. This increases flow into the wellbore.
Bullheading is a common non-circulating method for killing live wells prior to workovers. It involves pumping kill fluid into the tubing to displace produced fluids back into the formation. A bullheading schedule is generated using formation pressure, desired overbalance, fracture pressure, tubing specifications, and pump data to safely control pumping pressures within the initial and final maximum pressures. The schedule provides checkpoints to monitor pumping pressure and volume throughout the operation. Special attention should be paid to any increases in casing pressure which could indicate downhole issues.
Casing Seat depth and Basic casing design lecture 4.pdfssuserfec9d8
1. The maximum gas kick pressure from the total depth as the internal pressure.
2. Formation pore pressure at the casing shoe as the external pressure.
3. The casing must be designed to withstand the difference between the maximum internal gas kick pressure and external pore pressure, known as the resultant pressure.
This document discusses drilling fluid systems and their functions. It describes the classification of drilling muds as water-based or oil-based. Water-based muds can be further broken down and include bentonite muds, polymer muds, and muds with additives like gypsum, lime, potassium/lime, and mixed metal hydroxide. Oil-based muds include invert emulsion and mineral/synthetic oil-based muds. Key functions of drilling fluids are cooling and lubricating the drill bit, carrying cuttings to the surface, controlling formation pressure, and maintaining wellbore stability. Common measurements of mud properties are also outlined.
Drill stem test (DST) is one of the most famous on-site well testing that is used to unveil critical reservoir and fluid properties such as reservoir pressure, average permeability, skin factor and well potential productivity index. It is relatively cheap on-site test that is done prior to well completion. Upon the DST results, usually, the decision of the well completion is taken.
This document summarizes a project on well control and blowout prevention. It discusses causes of kicks such as insufficient mud weight and lost circulation. It describes shut-in procedures for land and offshore rigs which involve closing blowout preventers. It covers obtaining and interpreting shut-in pressures to determine formation and trapped pressures. Kill methods like wait and weight, engineer's method, and concurrent method are outlined. Variables that affect kill procedures like influx type and volume are identified. The document provides an example case study of a well control complication and kill operation.
The document discusses the functions and types of casing strings used in oil and gas wells. It describes the different casing strings like conductor casing, surface casing, intermediate casing, and production casing. It also covers casing design criteria like classifications based on outside diameter, length, connections, weight, and grade. The mechanical properties of casing are discussed in relation to withstanding tensile, burst, and collapse loads during drilling and production operations.
Drilling operations can encounter various problems related to geological uncertainties, wellbore stability issues, and depletion effects. Some key risks include uncertainties in pore pressure-fracture gradient measurements, mud volcanoes causing landslides or weak formations, fault zones providing pathways for fluid flow, and maintaining wellbore integrity in low-pressure depleted zones. Operators address these challenges through careful planning, identifying potential hazard areas using seismic data, selecting appropriate drilling fluid properties, and employing wellbore strengthening techniques and lost circulation materials when needed to prevent fluid losses and wellbore collapse.
This document discusses drilling mud, including its types, composition, properties, functions, and laboratory/field testing. It describes water-based muds and oil-based muds as the two main types, and their components such as liquids, solids, and chemicals. Key properties covered include density, viscosity, filtration, and gel strength. Important functions of drilling mud include hole cleaning, pressure control, cooling and lubrication. Common laboratory tests to evaluate mud properties and performance include measuring density, rheology, filtration, sand content, resistivity, and pH.
A drill stem test (DST) is used to test characteristics of a newly drilled well while the drilling rig is still on site. It can provide estimates of permeability, reservoir pressure, fluid types, wellbore damage, barriers and fluid contacts. There are three main methods to analyze DST data: Horner's plot method, type curve matching method, and computer matching. Type curve matching involves matching pressure change over time data from the DST to standard type curves to determine properties like permeability and skin factor. Gringarten type curves are commonly used and account for variations in pressure over time based on reservoir-well configurations.
Complete Casing Design with types of casing, casing properties, casing functions, design criteria and properties used for designing and one numerical problem
This document discusses various aspects of well planning such as pore pressure and fracture gradient determination, casing depth selection, and well configuration. It describes the different types of well planning for exploration, development, and completion/workover. Key factors in well planning include interaction between drilling and other departments to optimize costs, and fully evaluating rig and well design options. Typical well casing includes conductor, surface, intermediate, and production casing. Formulas are provided for pore pressure prediction based on overburden stress, hydrostatic pressure, and compaction effects. Criteria for selecting casing setting depths include controlling formation pressures and preventing differential pressure sticking.
Casing is essential for safely drilling oil and gas wells. It must withstand forces during drilling and through the life of the well. Different casing strings are run to isolate formations with different pressures and seal off problematic zones to allow deeper drilling. Surface casing isolates fresh water and supports blowout preventers. Intermediate casing increases pressure integrity to drill deeper and protects progress. Production casing houses completion equipment and isolates the producing zone. Liners are shorter strings hung from intermediate casing to complete zones economically. Proper casing and cementing is crucial to isolate formations and prevent communication between zones.
1. The document discusses different types of stuck pipe that can occur while drilling, including differential pressure pipe sticking and mechanical pipe sticking.
2. Differential pressure pipe sticking occurs when part of the drillstring embeds in the mudcake on the formation wall. Mechanical pipe sticking can be caused by cuttings accumulation, borehole instability, or key seating.
3. Methods to prevent or mitigate stuck pipe include maintaining low fluid loss and drilled solids levels, using smooth mudcake systems, and rotating drillstring. Common techniques for freeing stuck pipe include reducing hydrostatic pressure, oil spotting, or increasing mud weight.
This document provides an overview of lost circulation, which occurs when drilling fluid is lost into porous or fractured formations. It discusses the types and severity of lost circulation, as well as methods for preventing, locating, and treating lost circulation zones. Key points include that lost circulation can lead to blowouts if not addressed, and that preventing excessive downhole pressure and identifying weak formations are important. Locating lost zones involves surveys to detect where fluid flows into formations, while treatments require sealing fractures or pores with lost circulation materials.
This document discusses the design of drillstrings and bottom hole assemblies (BHAs). It covers the components of drillstrings including drill pipe, drill collars, heavy weight drill pipe, and stabilizers. It also discusses BHA configurations and the purpose and components of BHAs. The document provides information on selecting drill collars and drill pipe grades. It covers criteria for drillstring design including collapse pressure, tension loading, and dogleg severity analysis.
This document discusses various water-based mud systems used in drilling operations. It describes the basic systems commonly used like lignosulfonate systems and calcium treated systems. More complex systems are used as conditions change with increasing well depth, temperature and pressure. Factors that influence the choice of mud system include the application, geology of the formation, make-up water quality, drilling parameters, potential drilling problems, and rig equipment limitations. The document provides details on specific mud systems like potassium chloride PHPA mud, silicate mud and their components and applications.
1) The document discusses different types of drill bits used in drilling operations including PDC, natural diamond, TSP, impregnated diamond, roller cone, tooth, and insert bits.
2) It explains the IADC classification system for drill bits which codes them based on factors like cutting structure, bearing type, and application in soft to hard formations.
3) The IADC dull grading code characterizes used drill bits according to wear characteristics like erosion, broken cutters, and reasons for being pulled such as being worn out.
This document provides an overview of designing wells for high pressure high temperature (HPHT) environments. It discusses HPHT definitions, challenges, case studies, and recommendations for various well design aspects. Key points include defining three HPHT envelopes based on temperature and pressure limits, outlining completion, testing and data acquisition challenges, reviewing global HPHT fields and standards, analyzing an Indian HPHT case study, and providing recommendations for casing design, drilling fluids, cementing, and material selection tailored for HPHT wells.
DRILLING FLUIDS FOR THE HPHT ENVIRONMENTMohan Doshi
A BRIEF REVIEW OF THE DRILLING FLUIDS FOR DRILLING HPHT WELLS. HPHT WELLS ARE NOT BUSINESS AS USUAL AND THE SAME APPLIES TO HPHT DRILLING FLUIDS. THE FLUID CHEMISTRY AND THE FLUID COMPOSITION HAVE TO BE TAILORED TO MEET THE RIGORS OF THE HIGH TEMPERATURE ENVIRONMENT
A drilling fluid, or mud, is circulated during drilling operations to carry cuttings to the surface, control formation pressure and maintain wellbore stability, cool and lubricate the drill bit, and minimize damage to the reservoir. There are three main types of drilling fluids: gaseous (such as air), aqueous (such as water-based muds containing clay or polymer), and non-aqueous (such as oil-based or synthetic-based muds). Cuttings are removed from the drilling fluid using various solids control equipment and processes at the surface. Working with drilling fluids requires safety precautions as some components can be hazardous if not properly handled.
Rheology of Fluids Hydraulic Calculations & Drilling Fluid (Mud) Filtration T...Shaoor Kamal
This document summarizes two experiments conducted to investigate the rheology of drilling fluids and their filtration properties. In Experiment 2, the rheological behavior of two mud samples (Mud A and Mud B) was analyzed using a viscometer. Both muds exhibited similar shear thinning properties and were best described by the Herschel-Bulkley and power law rheological models. In Experiment 3, the filtration properties of the two muds were examined by measuring filter cake buildup and fluid invasion over time. Key results showed that the muds had similar rheology and filtration behavior.
Casing Seat depth and Basic casing design lecture 4.pdfssuserfec9d8
1. The maximum gas kick pressure from the total depth as the internal pressure.
2. Formation pore pressure at the casing shoe as the external pressure.
3. The casing must be designed to withstand the difference between the maximum internal gas kick pressure and external pore pressure, known as the resultant pressure.
This document discusses drilling fluid systems and their functions. It describes the classification of drilling muds as water-based or oil-based. Water-based muds can be further broken down and include bentonite muds, polymer muds, and muds with additives like gypsum, lime, potassium/lime, and mixed metal hydroxide. Oil-based muds include invert emulsion and mineral/synthetic oil-based muds. Key functions of drilling fluids are cooling and lubricating the drill bit, carrying cuttings to the surface, controlling formation pressure, and maintaining wellbore stability. Common measurements of mud properties are also outlined.
Drill stem test (DST) is one of the most famous on-site well testing that is used to unveil critical reservoir and fluid properties such as reservoir pressure, average permeability, skin factor and well potential productivity index. It is relatively cheap on-site test that is done prior to well completion. Upon the DST results, usually, the decision of the well completion is taken.
This document summarizes a project on well control and blowout prevention. It discusses causes of kicks such as insufficient mud weight and lost circulation. It describes shut-in procedures for land and offshore rigs which involve closing blowout preventers. It covers obtaining and interpreting shut-in pressures to determine formation and trapped pressures. Kill methods like wait and weight, engineer's method, and concurrent method are outlined. Variables that affect kill procedures like influx type and volume are identified. The document provides an example case study of a well control complication and kill operation.
The document discusses the functions and types of casing strings used in oil and gas wells. It describes the different casing strings like conductor casing, surface casing, intermediate casing, and production casing. It also covers casing design criteria like classifications based on outside diameter, length, connections, weight, and grade. The mechanical properties of casing are discussed in relation to withstanding tensile, burst, and collapse loads during drilling and production operations.
Drilling operations can encounter various problems related to geological uncertainties, wellbore stability issues, and depletion effects. Some key risks include uncertainties in pore pressure-fracture gradient measurements, mud volcanoes causing landslides or weak formations, fault zones providing pathways for fluid flow, and maintaining wellbore integrity in low-pressure depleted zones. Operators address these challenges through careful planning, identifying potential hazard areas using seismic data, selecting appropriate drilling fluid properties, and employing wellbore strengthening techniques and lost circulation materials when needed to prevent fluid losses and wellbore collapse.
This document discusses drilling mud, including its types, composition, properties, functions, and laboratory/field testing. It describes water-based muds and oil-based muds as the two main types, and their components such as liquids, solids, and chemicals. Key properties covered include density, viscosity, filtration, and gel strength. Important functions of drilling mud include hole cleaning, pressure control, cooling and lubrication. Common laboratory tests to evaluate mud properties and performance include measuring density, rheology, filtration, sand content, resistivity, and pH.
A drill stem test (DST) is used to test characteristics of a newly drilled well while the drilling rig is still on site. It can provide estimates of permeability, reservoir pressure, fluid types, wellbore damage, barriers and fluid contacts. There are three main methods to analyze DST data: Horner's plot method, type curve matching method, and computer matching. Type curve matching involves matching pressure change over time data from the DST to standard type curves to determine properties like permeability and skin factor. Gringarten type curves are commonly used and account for variations in pressure over time based on reservoir-well configurations.
Complete Casing Design with types of casing, casing properties, casing functions, design criteria and properties used for designing and one numerical problem
This document discusses various aspects of well planning such as pore pressure and fracture gradient determination, casing depth selection, and well configuration. It describes the different types of well planning for exploration, development, and completion/workover. Key factors in well planning include interaction between drilling and other departments to optimize costs, and fully evaluating rig and well design options. Typical well casing includes conductor, surface, intermediate, and production casing. Formulas are provided for pore pressure prediction based on overburden stress, hydrostatic pressure, and compaction effects. Criteria for selecting casing setting depths include controlling formation pressures and preventing differential pressure sticking.
Casing is essential for safely drilling oil and gas wells. It must withstand forces during drilling and through the life of the well. Different casing strings are run to isolate formations with different pressures and seal off problematic zones to allow deeper drilling. Surface casing isolates fresh water and supports blowout preventers. Intermediate casing increases pressure integrity to drill deeper and protects progress. Production casing houses completion equipment and isolates the producing zone. Liners are shorter strings hung from intermediate casing to complete zones economically. Proper casing and cementing is crucial to isolate formations and prevent communication between zones.
1. The document discusses different types of stuck pipe that can occur while drilling, including differential pressure pipe sticking and mechanical pipe sticking.
2. Differential pressure pipe sticking occurs when part of the drillstring embeds in the mudcake on the formation wall. Mechanical pipe sticking can be caused by cuttings accumulation, borehole instability, or key seating.
3. Methods to prevent or mitigate stuck pipe include maintaining low fluid loss and drilled solids levels, using smooth mudcake systems, and rotating drillstring. Common techniques for freeing stuck pipe include reducing hydrostatic pressure, oil spotting, or increasing mud weight.
This document provides an overview of lost circulation, which occurs when drilling fluid is lost into porous or fractured formations. It discusses the types and severity of lost circulation, as well as methods for preventing, locating, and treating lost circulation zones. Key points include that lost circulation can lead to blowouts if not addressed, and that preventing excessive downhole pressure and identifying weak formations are important. Locating lost zones involves surveys to detect where fluid flows into formations, while treatments require sealing fractures or pores with lost circulation materials.
This document discusses the design of drillstrings and bottom hole assemblies (BHAs). It covers the components of drillstrings including drill pipe, drill collars, heavy weight drill pipe, and stabilizers. It also discusses BHA configurations and the purpose and components of BHAs. The document provides information on selecting drill collars and drill pipe grades. It covers criteria for drillstring design including collapse pressure, tension loading, and dogleg severity analysis.
This document discusses various water-based mud systems used in drilling operations. It describes the basic systems commonly used like lignosulfonate systems and calcium treated systems. More complex systems are used as conditions change with increasing well depth, temperature and pressure. Factors that influence the choice of mud system include the application, geology of the formation, make-up water quality, drilling parameters, potential drilling problems, and rig equipment limitations. The document provides details on specific mud systems like potassium chloride PHPA mud, silicate mud and their components and applications.
1) The document discusses different types of drill bits used in drilling operations including PDC, natural diamond, TSP, impregnated diamond, roller cone, tooth, and insert bits.
2) It explains the IADC classification system for drill bits which codes them based on factors like cutting structure, bearing type, and application in soft to hard formations.
3) The IADC dull grading code characterizes used drill bits according to wear characteristics like erosion, broken cutters, and reasons for being pulled such as being worn out.
This document provides an overview of designing wells for high pressure high temperature (HPHT) environments. It discusses HPHT definitions, challenges, case studies, and recommendations for various well design aspects. Key points include defining three HPHT envelopes based on temperature and pressure limits, outlining completion, testing and data acquisition challenges, reviewing global HPHT fields and standards, analyzing an Indian HPHT case study, and providing recommendations for casing design, drilling fluids, cementing, and material selection tailored for HPHT wells.
DRILLING FLUIDS FOR THE HPHT ENVIRONMENTMohan Doshi
A BRIEF REVIEW OF THE DRILLING FLUIDS FOR DRILLING HPHT WELLS. HPHT WELLS ARE NOT BUSINESS AS USUAL AND THE SAME APPLIES TO HPHT DRILLING FLUIDS. THE FLUID CHEMISTRY AND THE FLUID COMPOSITION HAVE TO BE TAILORED TO MEET THE RIGORS OF THE HIGH TEMPERATURE ENVIRONMENT
A drilling fluid, or mud, is circulated during drilling operations to carry cuttings to the surface, control formation pressure and maintain wellbore stability, cool and lubricate the drill bit, and minimize damage to the reservoir. There are three main types of drilling fluids: gaseous (such as air), aqueous (such as water-based muds containing clay or polymer), and non-aqueous (such as oil-based or synthetic-based muds). Cuttings are removed from the drilling fluid using various solids control equipment and processes at the surface. Working with drilling fluids requires safety precautions as some components can be hazardous if not properly handled.
Rheology of Fluids Hydraulic Calculations & Drilling Fluid (Mud) Filtration T...Shaoor Kamal
This document summarizes two experiments conducted to investigate the rheology of drilling fluids and their filtration properties. In Experiment 2, the rheological behavior of two mud samples (Mud A and Mud B) was analyzed using a viscometer. Both muds exhibited similar shear thinning properties and were best described by the Herschel-Bulkley and power law rheological models. In Experiment 3, the filtration properties of the two muds were examined by measuring filter cake buildup and fluid invasion over time. Key results showed that the muds had similar rheology and filtration behavior.
it is a benficial slide who wants to know about the drilling fluids and the rhelogical aspects of the drilling fluids. the things are clear and very clear in this slide and this slide is very beneficial for the one who know basics of drilling fluids in a knowledgeable way
This document discusses the drilling fluid circulation system used in drilling operations. It describes the key components of the system including mud pumps, solids removal equipment, and treatment equipment. Mud pumps are typically positive displacement pumps, namely duplex or triplex pumps. The document provides details on how drilling fluid is pumped from the surface to the drill bit, circulates in the wellbore, and returns to the surface while removing cuttings.
This document summarizes a presentation about drilling fluids. It defines drilling fluid as a mixture of clay and chemicals pumped through a drill bit to provide hydrostatic pressure, suspend cuttings, cool and lubricate the bit, and provide information from the wellbore. The presentation covers the types of drilling fluids, their functions, additives used, and rheological properties measured. It also describes the drilling fluid circulation system and discusses drilling fluid considerations and emergency remedies.
This document provides information about drilling fluids used in oil and gas drilling operations. It discusses the key components and functions of drilling fluids, including bringing cuttings to the surface, controlling subsurface pressures, lubricating and cooling the drill bit. It also describes various types of drilling fluids like water-based muds, calcium muds, lignosulphonate muds, and KCl/polymer muds. The document discusses the role of clays and colloid chemistry in drilling fluids and outlines the properties and uses of different clay minerals.
This document discusses bentonite, its origins, and its use in drilling fluids. Bentonite is a volcanic ash that was formed during the Cretaceous Period and is found in large volumes in the western U.S. It is composed of stacked platelets that can absorb large quantities of water and expand up to 20 times its original volume. Bentonite is used as the base material for drilling fluids due to its ability to suspend cuttings and form a filter cake to control fluid loss. Polymers and other additives are used to modify the properties of bentonite drilling fluids for different soil conditions.
This document discusses non-damaging drilling fluids (NDDF) used to control formation damage during drilling. NDDF was developed using non-degradable and degradable constituents to prevent damage to productive reservoirs. The basic composition of NDDF includes salts, calcium carbonate, polymers, and biocides. Two common types of NDDF are based on micronized calcium carbonate and sodium/potassium formate salts. NDDF provides advantages over conventional drilling fluids like reducing invasion of fines and bridging pore throats to minimize damage during drilling.
The document outlines the life cycle of oil and gas wells, including planning, drilling, completion, production, and abandonment phases. It describes the planning process including well classification and formation pressure considerations. Key aspects of drilling are discussed such as rig types, crews, casing, and use of drilling mud to remove cuttings from the wellbore.
The document lists various components used in drilling operations. It mentions hoisting components, including the drawworks, crown block, travelling block, and deadline anchor. It also lists components of the rotary system, mud circulation system, drill pipe handling equipment, drill bits, fishing tools, and other miscellaneous drilling equipment.
Summer training project on drilling fluid at ongc pptKeshar Saini
This project “Study of drill cutting and Formulation of drilling fluid.” was performed in R&D LAB ONGC Dehradun. Study of drill cutting is done in terms of CST(capillary suction time), MBC(Methylene Blue Capacity) and XRD(X-ray diffraction).
• Later than several drilling fluid with different formulation are prepared and several tests (like Rheology Test, Lubricity Test, API Filter press, Linear swell Test and pH test) are performed on drilling fluid to check the suitability of it on drill cutting. Thus the suitable formulation of drilling fluid is found.
This document discusses drilling fluid systems. It provides information on:
- Drilling fluid functions such as providing hydrostatic pressure, keeping the drill bit cool, carrying cuttings, and limiting corrosion.
- Types of drilling fluids including water-based mud, oil-based mud, and synthetic-based mud.
- Components of an active drilling fluid system including pumps, pits, and the annular space in the wellbore.
- Factors that determine drilling fluid volume such as rig size and well design/depth.
- Rheological behavior models for drilling fluids based on relationships between shear stress and shear rate.
- Uses of drilling fluid rheology including calculating friction and surge pressures.
- Instruments for
1. Hydraulics is important for drilling operations to remove cuttings, balance pore and fracture pressures, and prevent wellbore collapse. It becomes more critical for HPHT and extended reach wells with small pressure margins.
2. Key components of the circulating system include the drill pipe, annulus, casing, open hole, drill collars, mud pump, mud pit, and drill bit. Pressure losses occur through these components and must be calculated and balanced against pore and fracture pressures.
3. Proper mud weight and viscosity are needed to provide adequate hydrostatic pressure and hole cleaning while avoiding fracturing. The equivalent circulating density accounts for both mud weight and pressure losses.
Rotary drilling rigs use a hoisting system to lower and raise the drill string. To estimate rotary torque before drilling, an empirical relation uses factors like drill string weight, depth, and weight on bit. Deeper holes require higher torque factors. The circulating system controls subsurface pressures, removes cuttings from the hole, transmits power to the bit, and provides formation information using drilling mud. Mud pumps are typically duplex or triplex positive displacement pumps, and their volumetric output can be calculated based on specifications like stroke length, liner diameter, rod diameter, and efficiency.
This document discusses mud filtration experiments. It aims to monitor the rate of fluid loss from a filter press under controlled conditions and measure the thickness of residue deposited on the filter paper. Filtration properties are important for understanding invasion into porous formations and filter cake buildup on wellbores. The experiment uses a standard filter press to test mud samples under static and dynamic filtration conditions at varying temperatures and pressures. Results like fluid loss volume and filter cake thickness indicate how much water/oil wetting and permeability damage may occur in formations. Formation damage can reduce productivity and is affected by factors like filter cake properties, filtrate invasion, and drilling/completion operations.
This document summarizes a student's fluid mechanics lab experiment on measuring mud density. The aim was to learn how to use a mud balance apparatus to measure the density of drilling mud and see how density changes with the addition of barite. The student first prepared a bentonite mud and measured its density. Barite was then added to increase the mud density, which was remeasured. Understanding mud density is important for maintaining proper hydrostatic pressure to prevent fluid influx from formations during drilling.
This document provides an overview of drilling and well construction methods for geothermal wells. It describes the main types of drilling rigs and methods used, including cable tool rigs, rotary drilling rigs, and variations such as downhole hammers and reverse circulation. Cable tool rigs are slower but can drill through difficult formations and produce accurate samples. Rotary methods are more common and faster but require drilling fluids. Proper cementing of wells is also discussed as being important for safety, well productivity, and preventing fluid mixing.
Drilling fluids, also called drilling muds, are circulated during rotary drilling operations to perform critical functions such as cooling the drill bit, removing drill cuttings from the wellbore, maintaining well pressure, and providing information to geologists. The key types of drilling fluids are water-based mud, oil-based mud, and air/foam. Drilling fluid properties like density, viscosity, gel strength, and filtration must be carefully controlled to prevent problems during drilling like blowouts, stuck pipe, and hole instability.
This document provides an overview of drilling fluids. It discusses the key functions of drilling fluids, including transporting cuttings to the surface, cleaning the drill bit, providing hydrostatic pressure, preventing fluid loss, and lubricating and cooling the drill string. It also describes common drilling fluid types like water-based and oil-based muds. Important drilling fluid properties are defined, such as density, viscosity, gel strength, and fluid loss. Common drilling fluid additives and their purposes are explained. Hazards that can be addressed by proper fluid selection and properties management are also outlined.
This document discusses drilling fluids and their properties. It provides an overview of the principal functions of drilling fluids, which include subsurface pressure control, cuttings removal and transport, suspension of solid particles, sealing of permeable formations, stabilizing the wellbore, preventing formation damage, cooling and lubricating the bit, transmitting hydraulic horsepower to the bit, facilitating collection of formation data, partial support of the drill string and casing weights, controlling corrosion, and assisting in cementing and completion. It also discusses drilling fluid classifications, properties such as viscosity and rheology, and key components of drilling fluids.
The document discusses various borehole problems that can be encountered during drilling operations, including:
- Pipe sticking caused by differential pressure or mechanical forces
- Lost circulation occurring when fluid flows into porous or fractured formations
- Hole deviation due to factors like formation heterogeneity, drilling equipment, and drilling parameters
- Pipe failures from twistoff, parting, collapse, burst, or fatigue
- Borehole instability issues like hole closure, enlargement, fracturing or collapse
- Mud contamination from solids, salts, or formation fluids entering the drilling fluid system
- Formation damage near the wellbore from plugging by solids or fluid invasion impairing permeability
Proper planning, monitoring, and application of best
WELL COMPLETION, WELL INTERVENTION/ STIMULATION, AND WORKOVERAndi Anriansyah
This document discusses various well completion, intervention, and workover topics including:
- Well completion involves preparing the well for production by installing equipment like casing and tubing.
- Open hole and cased hole completions are described, along with advantages and disadvantages of each.
- Well intervention operations like scale removal, acidizing, and sand cleaning are performed during production.
- Formation damage from fluids introduced into the well is also discussed.
- Stimulation techniques like acidizing and hydraulic fracturing aim to increase well productivity. The document outlines the processes, equipment, and evaluation of these operations.
- Other topics covered include intelligent well completions, perforating, sand control, squeeze cement
The fifth presentation of a series of presentations on Operations Geology. Very basic, just to introduce beginners to operations geology. I hope the end users will find this and the following presentations very helpful.
This document provides an overview of a course on drilling fluids technology. It discusses the key functions of drilling fluids, including hole cleaning by transporting cuttings, pressure control by balancing subsurface pressures, suspending solids to prevent settling, minimizing formation damage, isolating fluids from the formation through filter cakes, providing cooling and lubrication, and powering downhole tools. It covers topics like mud properties and measurements, mud rheology, types of muds, hydraulics, pressure calculations, and containment. The first chapter focuses on the functions of drilling fluids in more depth.
This document provides information on various topics related to well planning and design, including:
- Well data requirements such as detailed lithology, formation fluids, reservoir data, and pressure data.
- Global basin screening, basin analysis, play analysis, prospect analysis, rock types, and reactive formations.
- Exploration strategy, including global basin analysis, basin analysis, play analysis, prospect analysis, and prospect volume estimation.
- Pore pressure and fracture pressure determination, including leakage tests to estimate the fracture gradient at casing seats.
This document provides an overview of key concepts in petroleum engineering, including permeability, geophysics techniques for oil and gas exploration like seismic surveys, and reservoir engineering essentials. It discusses permeability measurement methods, factors that affect permeability, and types of permeability. It also summarizes different geophysics techniques like seismic surveys, gravity surveys, electromagnetic surveys, and magnetic surveys. Finally, it outlines the essential elements and processes for hydrocarbon accumulation, including the need for a trap, reservoir, source rock, and seal.
This document discusses the functions and types of drilling fluids. It describes how drilling fluids transport cuttings to the surface, clean drill bits, provide downhole pressure control, prevent fluid loss into formations, and power downhole tools. The key types of drilling fluids are water-based mud, oil-based mud, and gas-based fluids. Water-based mud is the most common and uses additives to control density, viscosity, and clay chemistry. Oil-based mud is used in reactive shale formations and has advantages in high temperatures but also environmental and health disadvantages.
The document discusses drilling fluids used in oil and gas drilling. It outlines the basic functions of drilling fluids, which include transporting cuttings to the surface, providing well control, preserving wellbore stability, minimizing formation damage, cooling and lubricating the drill string, and providing information about the wellbore. It also describes different types of drilling fluids, tests performed on drilling fluids, challenges related to drilling fluids like lost circulation and stuck pipe, and solids control and waste management techniques. The overall document provides a comprehensive overview of drilling fluids used in oil and gas drilling operations.
The document discusses drilling fluids used in oil and gas drilling. It outlines the basic functions of drilling fluids, which include transporting cuttings to the surface, providing well control, preserving wellbore stability, minimizing formation damage, cooling and lubricating the drill string, and providing information about the wellbore. It describes different types of drilling fluids and tests used to evaluate drilling fluid properties. It also covers challenges related to drilling fluids like lost circulation and stuck pipe. Finally, it discusses solids control and waste management techniques used to separate solids from drilling fluids and minimize waste volumes.
Batch sedimentation
What is sedimentation…?
Goals of gravity s sedimentation
Applications of sedimentation
zone settling velocity
Factors affecting zone settling velocity
Design of Zone Settling Tanks
What is Thickener and Clarifiers…?
Thickener Area Calculation
Types of clarifier
Drill bits cut into rock during oil and gas well drilling. There are different types of drill bits made of materials like steel, tungsten carbide, or diamonds suited for various conditions. Drill bits are designed to maximize the rate of penetrating rock formations and provide a long service life. Drilling fluid, or mud, is circulated through the drill string to carry rock cuttings up from the drill bit and exert pressure to prevent fluid from entering the borehole. Common mud types include water-based and oil-based, and mud properties are monitored to fulfill functions like carrying cuttings and suspending weighting materials.
Episode 44 : Flow Behavior of Granular Materials and PowdersPart IIISAJJAD KHUDHUR ABBAS
Episode 44 : Flow Behavior of Granular Materials and PowdersPart III
Law of hydrodynamics do not apply to the flow of solid granular materials through orifices:
Pressure is not distributed equally in all directions due to the development of arches and to frictional forces between the granules.
The rate of flow is not proportional to the head, except at heads smaller than the container diameter.
No provision is made in hydrodynamics for size and shape of particles, which greatly influence the flow rate.
SAJJAD KHUDHUR ABBAS
Ceo , Founder & Head of SHacademy
Chemical Engineering , Al-Muthanna University, Iraq
Oil & Gas Safety and Health Professional – OSHACADEMY
Trainer of Trainers (TOT) - Canadian Center of Human
Development
The document discusses well completion processes. It describes the different types of well casing installed during completion, including conductor, surface, intermediate, production, and liner casing. It also discusses functions of casing like strengthening the wellbore and preventing fluid migration. The document outlines various completion methods like open hole, cemented liners, gravel packs, and describes how zones are produced. It classifies completions based on reservoir interface, production method (natural flow, artificial lift like rod pumps and ESPs), and number of zones. The artificial lift methods support production when natural reservoir pressure declines.
1. Drilling fluids serve several essential functions including removing drill cuttings from the wellbore, controlling formation pressure, and maintaining wellbore stability.
2. A mud engineer monitors and treats the mud to keep its properties and chemistry within recommended limits to optimize drilling aims.
3. The selection of a drilling fluid type is based on factors like drilling problems encountered, compatibility with the fluid in use, costs, availability of products, and environmental considerations.
dewatering, hydrometallurgy and plant flowsheet of aluminium extraction mine...B P Ravi
The document discusses dewatering methods used in mineral processing, focusing on thickening and filtration. It describes thickening processes like sedimentation and clarification that are used to remove up to 80% of water from slurries. Thickeners are large tanks that use rotating arms to rake settled solids towards the center outlet. Filtration can further dewater thickened pulps to a filter cake with 80-90% solids. The document provides details on thickener design, construction, operation, and the theory behind calculating thickener area based on feed rates and settling velocities.
THE EFFECTS OF GEL STRENGHT ON THE OVERALLfelix aladetan
This document discusses gel strength, which is a measurement of the shear stress in drilling mud after it has been static for a period of time. It represents the mud's ability to suspend solids and cuttings when circulation is stopped. The document defines gel strength, describes how it is measured over 10 seconds, 10 minutes and 30 minutes, and identifies the factors that affect gel strength in water-based and oil-based muds. Both excessive and weak gel strengths can cause problems like stuck pipe or inadequate cutting suspension, so maintaining the proper gel strength is important for effective hole cleaning and drilling operations.
Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapte...University of Maribor
Slides from talk presenting:
Aleš Zamuda: Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapter and Networking.
Presentation at IcETRAN 2024 session:
"Inter-Society Networking Panel GRSS/MTT-S/CIS
Panel Session: Promoting Connection and Cooperation"
IEEE Slovenia GRSS
IEEE Serbia and Montenegro MTT-S
IEEE Slovenia CIS
11TH INTERNATIONAL CONFERENCE ON ELECTRICAL, ELECTRONIC AND COMPUTING ENGINEERING
3-6 June 2024, Niš, Serbia
KuberTENes Birthday Bash Guadalajara - K8sGPT first impressionsVictor Morales
K8sGPT is a tool that analyzes and diagnoses Kubernetes clusters. This presentation was used to share the requirements and dependencies to deploy K8sGPT in a local environment.
Redefining brain tumor segmentation: a cutting-edge convolutional neural netw...IJECEIAES
Medical image analysis has witnessed significant advancements with deep learning techniques. In the domain of brain tumor segmentation, the ability to
precisely delineate tumor boundaries from magnetic resonance imaging (MRI)
scans holds profound implications for diagnosis. This study presents an ensemble convolutional neural network (CNN) with transfer learning, integrating
the state-of-the-art Deeplabv3+ architecture with the ResNet18 backbone. The
model is rigorously trained and evaluated, exhibiting remarkable performance
metrics, including an impressive global accuracy of 99.286%, a high-class accuracy of 82.191%, a mean intersection over union (IoU) of 79.900%, a weighted
IoU of 98.620%, and a Boundary F1 (BF) score of 83.303%. Notably, a detailed comparative analysis with existing methods showcases the superiority of
our proposed model. These findings underscore the model’s competence in precise brain tumor localization, underscoring its potential to revolutionize medical
image analysis and enhance healthcare outcomes. This research paves the way
for future exploration and optimization of advanced CNN models in medical
imaging, emphasizing addressing false positives and resource efficiency.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
Comparative analysis between traditional aquaponics and reconstructed aquapon...bijceesjournal
The aquaponic system of planting is a method that does not require soil usage. It is a method that only needs water, fish, lava rocks (a substitute for soil), and plants. Aquaponic systems are sustainable and environmentally friendly. Its use not only helps to plant in small spaces but also helps reduce artificial chemical use and minimizes excess water use, as aquaponics consumes 90% less water than soil-based gardening. The study applied a descriptive and experimental design to assess and compare conventional and reconstructed aquaponic methods for reproducing tomatoes. The researchers created an observation checklist to determine the significant factors of the study. The study aims to determine the significant difference between traditional aquaponics and reconstructed aquaponics systems propagating tomatoes in terms of height, weight, girth, and number of fruits. The reconstructed aquaponics system’s higher growth yield results in a much more nourished crop than the traditional aquaponics system. It is superior in its number of fruits, height, weight, and girth measurement. Moreover, the reconstructed aquaponics system is proven to eliminate all the hindrances present in the traditional aquaponics system, which are overcrowding of fish, algae growth, pest problems, contaminated water, and dead fish.
A SYSTEMATIC RISK ASSESSMENT APPROACH FOR SECURING THE SMART IRRIGATION SYSTEMSIJNSA Journal
The smart irrigation system represents an innovative approach to optimize water usage in agricultural and landscaping practices. The integration of cutting-edge technologies, including sensors, actuators, and data analysis, empowers this system to provide accurate monitoring and control of irrigation processes by leveraging real-time environmental conditions. The main objective of a smart irrigation system is to optimize water efficiency, minimize expenses, and foster the adoption of sustainable water management methods. This paper conducts a systematic risk assessment by exploring the key components/assets and their functionalities in the smart irrigation system. The crucial role of sensors in gathering data on soil moisture, weather patterns, and plant well-being is emphasized in this system. These sensors enable intelligent decision-making in irrigation scheduling and water distribution, leading to enhanced water efficiency and sustainable water management practices. Actuators enable automated control of irrigation devices, ensuring precise and targeted water delivery to plants. Additionally, the paper addresses the potential threat and vulnerabilities associated with smart irrigation systems. It discusses limitations of the system, such as power constraints and computational capabilities, and calculates the potential security risks. The paper suggests possible risk treatment methods for effective secure system operation. In conclusion, the paper emphasizes the significant benefits of implementing smart irrigation systems, including improved water conservation, increased crop yield, and reduced environmental impact. Additionally, based on the security analysis conducted, the paper recommends the implementation of countermeasures and security approaches to address vulnerabilities and ensure the integrity and reliability of the system. By incorporating these measures, smart irrigation technology can revolutionize water management practices in agriculture, promoting sustainability, resource efficiency, and safeguarding against potential security threats.
ACEP Magazine edition 4th launched on 05.06.2024Rahul
This document provides information about the third edition of the magazine "Sthapatya" published by the Association of Civil Engineers (Practicing) Aurangabad. It includes messages from current and past presidents of ACEP, memories and photos from past ACEP events, information on life time achievement awards given by ACEP, and a technical article on concrete maintenance, repairs and strengthening. The document highlights activities of ACEP and provides a technical educational article for members.
DEEP LEARNING FOR SMART GRID INTRUSION DETECTION: A HYBRID CNN-LSTM-BASED MODELgerogepatton
As digital technology becomes more deeply embedded in power systems, protecting the communication
networks of Smart Grids (SG) has emerged as a critical concern. Distributed Network Protocol 3 (DNP3)
represents a multi-tiered application layer protocol extensively utilized in Supervisory Control and Data
Acquisition (SCADA)-based smart grids to facilitate real-time data gathering and control functionalities.
Robust Intrusion Detection Systems (IDS) are necessary for early threat detection and mitigation because
of the interconnection of these networks, which makes them vulnerable to a variety of cyberattacks. To
solve this issue, this paper develops a hybrid Deep Learning (DL) model specifically designed for intrusion
detection in smart grids. The proposed approach is a combination of the Convolutional Neural Network
(CNN) and the Long-Short-Term Memory algorithms (LSTM). We employed a recent intrusion detection
dataset (DNP3), which focuses on unauthorized commands and Denial of Service (DoS) cyberattacks, to
train and test our model. The results of our experiments show that our CNN-LSTM method is much better
at finding smart grid intrusions than other deep learning algorithms used for classification. In addition,
our proposed approach improves accuracy, precision, recall, and F1 score, achieving a high detection
accuracy rate of 99.50%.
International Conference on NLP, Artificial Intelligence, Machine Learning an...gerogepatton
International Conference on NLP, Artificial Intelligence, Machine Learning and Applications (NLAIM 2024) offers a premier global platform for exchanging insights and findings in the theory, methodology, and applications of NLP, Artificial Intelligence, Machine Learning, and their applications. The conference seeks substantial contributions across all key domains of NLP, Artificial Intelligence, Machine Learning, and their practical applications, aiming to foster both theoretical advancements and real-world implementations. With a focus on facilitating collaboration between researchers and practitioners from academia and industry, the conference serves as a nexus for sharing the latest developments in the field.
3. • Drilling mud is one of the most important elements of any drilling operation.
• The mud has a number of functions which must all be optimised to ensure
safety and minimum hole problems.
• Failure of the mud to meet its design functions can prove extremely costly in
terms of materials and time, and can also jeopardise the successful
completion of the well and may even result in major problems such as stuck
pipe, kicks or blowouts.
• There are basically two types of drilling mud:
• water-based and oil-based, depending on whether the continuous phase is
water or oil.
• Then there are a multitude of additives which are added to either change
the mud density or change its chemical properties.
4. Drilling Fluid Selection: Data Requirements
• The following information should be collected and used when selecting drilling
fluid or fluids for a particular well.
Pore pressure /fracture gradient plots to establish the minimum / maximum mud
weights to be used on the whole well.
Offset well data (drilling completion reports, mud recaps, mud logs etc.) from
similar wells in the area to help establish successful mud systems, problematic
formations, potential hazards, estimated drilling time etc.
Geological plot of the prognosed lithology.
Casing design programme and casing seat depths. The casing scheme effectively
divides the well into separate sections; each hole section may have similar
formation types, similar pore pressure regimes or similar reactivity to mud.
Basic mud properties required for each open hole section before it is cased off.
Restrictions that might be enforced in the area i.e. government legislation in the
area, environmental concerns etc.
5. Drilling Fluid Functions
The drilling mud must perform the following basic functions:
1. To control sub-surface pressures by providing hydrostatic pressure greater
than the formation pressure. This property depends on the mud weight
which, in turn, depends on the type of solids added to the fluid making up the
mud and the density of the continuous phase.
2. To remove the drilled cuttings from the hole. The removal of cuttings
depends on the viscous properties called "Yield Point" which influences the
carrying capacity of the flowing mud and "gels" which help to keep the
cuttings in suspension when the mud is static. The flow rate of mud is also
critical in cleaning the hole.
3. To cool and lubricate the drill bit and drillpipe.
6. 4. To prevent the walls of the hole from caving. This function is provided by
the formation of a stable mud cake on the walls of the wellbore, somewhat
like plastering the walls of a room to keep them from flaking.
5. To release the drilled cuttings at the surface.
6. To prevent or minimise damage to the formations penetrated by having
minimum fluid loss into the formation.
7. To assist in the gathering of the maximum information from the formations
being drilled.
8. To suspend the cuttings and weighing material when circulation is stopped
(gelation). This property is provided by gels and low shear viscosity properties.
9. To minimise the swelling stresses caused by the reaction of the mud with
the shale formations. This reaction can cause hole erosion or cavings resulting
in an unstable wellbore. Minimisation of wellbore instability is provided by the
"inhibition" character of the drilling mud.
7. However, when selecting the fluid, consideration must also be given to:
The environmental impact of using the fluid
The cost of the fluid
The impact of the fluid on production from the pay zone
8. Remove cuttings from the Wellbore:
The primary function of drilling fluid is to ensure that the rock cuttings
generated by the drilllbit are continuously removed from the wellbore.
If these cuttings are not removed from the bit face the drilling efficiency will
decrease. If these cuttings are not transported up the annulus between the
drillstring and wellbore efficiently the drillstring will become stuck in the
wellbore.
The mud must be designed such that it can:
Carry the cuttings to surface while circulating
Suspend the cuttings while not circulating
Drop the cuttings out of suspension at surface.
9. The carrying capacity of the mud depends on the annular velocity, density
and viscosity of the mud.
The ability to suspend the cuttings depends on the gelling (thixotropic)
properties of the mud.
This gel forms when circulation is stopped and the mud is static.
The drilled solids are removed from the mud at surface by mechanical
devices such as shale shakers, desanders and desilters
It is not economically feasible to remove all the drilled solids before re-
circulating the mud.
However, if the drilled solids are not removed the mud may require a lot of
chemical treatment and dilution to control the rheological properties of the
mud.
10. Prevent Formation Fluids Flowing into the Wellbore:
The hydrostatic pressure exerted by the mud column must be high enough to
prevent an influx of formation fluids into the wellbore.
However, the pressure in the wellbore must not be too high or it may cause the
formation to fracture and this will result in the loss of expensive mud into the
formation.
The flow of mud into the formation whilst drilling is known as lost circulation. This
is because a certain proportion of the mud is not returning to surface but flowing
into the formation.
• The pressure in the wellbore will be equal to:
P = 0.052 x MW x TVD
• where,
P = hydrostatic pressure (psi)
MW = mud density of the mud or mud weight (ppg)
TVD = true vertical depth of point of interest = vertical height of mud column (ft)
11. Maintain Wellbore Stability:
Data from adjacent wells will be useful in predicting borehole stability problems
that can occur in troublesome formations (eg unstable shales, highly permeable
zones, lost circulation, overpressured zones)
Shale instability is one of the most common problems in drilling operations.
This instability may be caused by either one or both of the following two
mechanisms:
the pressure differential between the bottom hole pressure in the borehole and
the pore pressures in the shales and/or,
hydration of the clay within the shale by mud filtrate containing water.
The instability caused by the pressure differential between the borehole and the
pore pressure can be overcome by increasing the mudweight.
The hydration of the clays can only be overcome by using non water-based muds,
or partially addressed by treating the mud with chemicals which will reduce the
ability of the water in the mud to hydrate the clays in the formation. These muds
are known as inhibited muds.
12. Cool and Lubricate the Bit:
The rock cutting process will, in particular with PDC bits, generate a great
deal of heat at the bit. Unless the bit is cooled, it will overheat and quickly
wear out.
The circulation of the drilling fluid will cool the bit down and help lubricate
the cutting process.
13. Transmit Hydraulic Horsepower to Bit:
As fluid is circulated through the drillstring, across the bit and up the
annulus of the wellbore the power of the mud pumps will be expended in
frictional pressure losses.
The efficiency of the drilling process can be significantly enhanced if
approximately 65% of this power is expended at the bit.
The pressure losses in the system are a function of the geometry of the
system and the mud properties such as viscosity, yield point and mud
weight.
The distribution of these pressure losses can be controlled by altering the
size of the nozzles in the bit and the flowrate through the system.
14. Drilling Fluid Additives
• There are many drilling fluid additives which are used to develop the key
properties of the mud.
• The variety of fluid additives reflect the complexity of mud systems currently in
use. The complexity is also increasing daily as more difficult and challenging
drilling conditions are encountered.
The most common types of additives used in water-based and oil-based muds are:
Weighting Materials
Viscosifiers
Filtration Control Materials
Rheology Control Materials
Alkalinity and pH Control Materials
Lost Circulation Control Materials
Lubricating Materials
Shale Stabilizing Materials
15. WEIGHTING MATERIALS:
• Weighting materials or densifiers are solids material which when suspended
or dissolved in water will increase the mud weight.
• Most weighting materials are insoluble and require viscosifers to enable
them to be suspended in a fluid.
• Clay is the most common viscosifier.
• Mud weights higher than water (8.3 ppg) are required to control formation
pressures and to help combat the effects of sloughing or heaving shales that
may be encountered in stressed areas.
• The specific gravity of the material controls how much solids material
(fractional volume) is required to produce a certain mud weight.
16.
17. MOST COMMONLY USED WEIGHTING MATERIALS
• Barite
• Iron Minerals: Iron Oxides, Iron Carbonate, Illmenite
• Calcium Carbonates:Dolomite
• Lead Sulphides
• Soluble Salts: Potassium Chloride (KCl), Sodium Chloride (NaCl), Sodium
Formate (NaHCO2), Calcium Chloride (CaCl2), Potassium Formate (KHCO2),
Calcium Bromide (CaBr2), Caesium Formate, Zinc Bromide (ZnBr2)
18. VISCOSIFIERS:
• The ability of drilling mud to suspend drill cuttings and weighting materials
depends entirely on its viscosity.
• Without viscosity, all the weighting material and drill cuttings would settle
to the bottom of the hole as soon as circulation is stopped.
• One can think of viscosity as a structure built within the water or oil phase
which suspends solid material.
• In practice, there are many solids which can be used to increase the
viscosity of water or oil.
• The effects of increased viscosity can be felt by the increased resistance to
fluid flow; in drilling this would manifest itself by increased pressure losses in
the circulating system.
21. FILTRATION CONTROL MATERIALS:
Filtration control materials are compounds which reduce the amount of fluid
that will be lost from the drilling fluid into a subsurface formation caused by
the differential pressure between the hydrostatic pressure of the fluid and the
formation pressure.
• Bentonite, polymers, starches and thinners or deflocculants all function as
filtration control agents.
• Bentonite imparts viscosity and suspension as well as filtration control. The
flat, "plate like“ structure of bentonite packs tightly together under pressure
and forms a firm compressible filter cake, preventing fluid from entering the
formation
22. • Polymers such as Polyanionic cellulose (PAC) and Sodium
Carboxymethylcellulose (CMC) reduce filtrate mainly when the hydrated
polymer chains absorb onto the clay solids and plug the pore spaces of the
filter cake preventing fluid seeping through the filter cake and formation.
• Filtration is also reduced as the polymer viscosifies the mud thereby creating
a viscosified structure to the filtrate making it difficult for the filtrate to seep
through.
• Starches function in a similar way to polymers. The free water is absorbed by
the sponge like material which aids in the reduction of fluid loss.
• Starches form very compressible particles that plug the small openings in the
filter cake.
• Thinners and deflocculants function as filtrate reducers by separating the
clay flock’s or groups enabling them to pack tightly to form a thin, flat filter
cake
23. RHEOLOGY CONTROL MATERIALS:
• When efficient control of viscosity and gel development cannot be achieved by
control of viscosifier concentration, materials called "thinners", "dispersants",
and/or "deflocculants“ are added.
• These materials cause a change in the physical and chemical interactions between
solids and/or dissolved salts such that the viscous and structure forming properties
of the drilling fluid are reduced.
• Thinners are also used
to reduce filtration and cake thickness,
to counteract the effects of salts,
to minimize the effect of water on the formations drilled,
to emulsify oil in water,
and to stabilize mud properties at elevated temperatures.
Materials commonly used as thinners in clay- based drilling fluids are classified as:
(1) plant tannins, (2) lignitic materials, (3) lignosulfonates, and (4) low molecular
weight, synthetic, water soluble polymers.
24. ALKALINITY AND PH CONTROL MATERIALS:
The pH affects several mud properties including:
• detection and treatment of contaminants such as cement and soluble
carbonates
• solubility of many thinners and divalent metal ions such as calcium and
magnesium
Alkalinity and pH control additives include: NaOH, KOH, Ca(OH)2, NaHCO3 and
Mg(OH)2.
These are compounds used to attain a specific pH and to maintain optimum
pH and alkalinity in water base fluids.
25. LOST CIRCULATION CONTROL MATERIALS:
CAUSES OF LOST CIRCULATION:
• Lost circulation is the loss of mud or cement to the formation during drilling
operations. Lost circulation causes:
increased well costs, due to lost rig time and loss of expensive drilling fluid
loss of accurate hole monitoring
well control problems.
LOST CIRCULATION MATERIAL:
• There are numerous types of lost circulation material (LCM) available which
can be used according to the type of losses experienced. Typical LCM
materials used are:
26. a. Conventional LCM
These include:
1. Flakes: includes mica and cellophane
2. Granular: includes nutshells, calcium carbonate and salt
3. Fibrous: includes glass fibre, wood fibre and animal fibre
b. Reinforcing Plugs and Cement
• These are specialised plugs and are only used as a last resort if every thing
else fails.
Two types of reinforcing plugs are in common use:
• Oil bentonite plug (water based muds)
• Water organophilic clay plug (oil based muds)
27. Oil/Bentonite Plug
• The use of this plug is based on the fact that bentonite does not hydrate in
oil but when spotted downhole it will contact water, hydrate and with oil
forms a strong plug.
• The pill is pumped to the loss zone with spacers ahead and behind to
prevent it from contacting the water based mud en route to the loss zone.
• When the pill is finally spotted, it will contact water and will hydrate and seal
the loss zone.
Water/Organophilic Clay Plug
• For oil based mud, the reverse of the above is used. An organophilic clay,
which yields (disperse) in oil based mud but not in water, is mixed with water
and is pumped as a pill to the loss zone.
• On contact with the oil mud downhole it will form a strong solid material.
The pill
must be pumped with a spacer ahead and behind to prevent it from
contacting the oil based mud en route to the loss zone
28. LUBRICATING MATERIALS:
• Lubricating materials are used mainly to reduce friction between the
wellbore and the drillstring.
• This will in turn reduce torque and drag which is essential in highly deviated
and horizontal wells.
• Lubricating materials include: oil (diesel, mineral, animal, or vegetable
• oils), surfactants, graphite, asphalt, gilsonite, polymer and glass beads
29. SHALE STABILIZING MATERIALS:
• There are many shale problems which may be encountered while drilling
sensitive highly hydratable shale sections.
• Essentially, shale stabilization is achieved by the prevention of water
contacting the open shale section.
• This can occur when the additive encapsulates the shale or when a specific
ion such as potassium actually enters the exposed shale section and
neutralises the charge on it.
• Shale stablisers include: high molecular weight polymers, hydrocarbons,
potassium and calcium salts (e.g. KCl) and glycols.
• Field experience indicates that complete shale stabilisation can not be
obtained from polymers only and that soluble salts must also be present in
the aqueous phase to stabilize hydratable shales.
30. Drilling Fluid Types
• A drilling fluid can be classified by the nature of its continuous fluid phase.
There are three types of drilling fluids:
1. Water Based Muds
2. Oil Based Muds
3. Gas Based Muds
31.
32. WATER BASED MUD:
• These are fluids where water is the continuous phase. The water may be
fresh, brackish or seawater, whichever is most convenient and suitable to the
system or is available.
• Water-based muds consist of a mixture of solids, liquids and chemicals.
• Some solids (clays) react with the water and chemicals in the mud and are
called active solids.
• The activity of these solids must be controlled in order to allow the mud to
function properly.
• The solids which do not react within the mud are called inactive or inert
solids (e.g. Barite).
• The other inactive solids are generated by the drilling process.
• Fresh water is used as the base for most of these muds, but in offshore
drilling operations salt water is more readily available.
33. The following designations are normally used to define the classifications of
water based drilling fluids:
1. Non-dispersed-Non - inhibited
2. Non-dispersed - Inhibited
3. Dispersed - Non-inhibited
4. Dispersed - Inhibited
34. • The main disadvantage of using water based muds is that the water in these
muds causes instability in shales.
• Shale is composed primarily of clays and instability is largely caused by
hydration of the clays by mud containing water.
• Shales are the most common rock types encountered while drilling for oil
and gas and give rise to more problems per meter drilled than any other
type of formation.
• In addition, the inferior wellbore quality often encountered in shales may
make logging and completion operations difficult or impossible.
• In the 1970s, the industry turned increasingly towards oil-based mud, OBM
as a means of controlling reactive shales. Oil-based muds are similar in
composition to water-based except that the continuous phase is oil.
• In an invert oil emulsion mud (IOEM) water may make up a large percentage
of the volume, but oil is still the continuous phase. (The water is dispersed
throughout the system as droplets).
35.
36. • Non-Inhibited means that the fluid contains no additives to inhibit hole
problems.
• Inhibited means that the fluid contains inhibiting ions such as chloride,
potassium or calcium or a polymer which suppresses the breakdown of the
clays by charge association and or encapsulation.
• Dispersed means that thinners have been added to scatter chemically the
bentonite (clay) and reactive drilled solids to prevent them from building
viscosity.
• Non-Dispersed means that the clay particles are free to find their own
dispersed equilibrium in the water phase.
• Non-dispersed-non-inhibited fluids do not contain inhibiting ions such as
chloride (Cl-), calcium (Ca2+) or potassium (K+) in the continuous phase and
do not utilize chemical thinners or dispersants to affect control of rheological
properties.
37. • Non-dispersed- inhibited fluids contain inhibiting ions in the continuous
phase, however they do not utilize chemical thinners or dispersants.
• Dispersed-non-inhibited fluids do not contain inhibiting ions in the
continuous phase, but they do rely on thinners or dispersants such as
phosphates, lignosulfonate or lignite to achieve control of the fluids'
rheological properties.
• Inhibited dispersed contain inhibiting ions such as calcium (Ca2+) or
potassium (K+) in the continuous phase and rely on chemical thinners or
dispersants to control the fluids rheological properties
38. COMPLETION AND WORKOVER FLUIDS
• These are fluids are designed to be non-damaging to the reservoir during the
completion of and workover a well.
• They are usually brines (salty water) which can be made up with up to three
different salts depending on the required density. Commonly seawater or
sodium chloride is used. Below is a list of salt types and their density ranges
39. OIL BASED MUDS:
• An oil based mud system is one in which the continuous phase of a drilling
fluid is oil. When water is added as the discontinuous phase then it is called
an invert emulsion.
• These fluids are particularly useful in drilling production zones, shales and
other water sensitive formations, as clays do not hydrate or swell in oil.
• They are also useful in drilling high angle/horizontal wells because of their
superior lubricating properties and low friction values between the steel and
formation which result in reduced torque and drag.
• Invert emulsion fluids (IEFs) are more cost-effective than water muds in the
following situations:
• Shale stability • Temperature stability • Lubricity • Corrosion resistance
• Stuck pipe prevention • Contamination • Production protection
40. Oil based muds are subject to strict Government Legislations and so serious
thought should be given to alternative systems.
There are two types of oil based muds:
• Invert Emulsion Oil Muds
• Pseudo Oil Based Mud
INVERT EMULSION OIL MUD
• The basic components of a typical low toxicity invert emulsion fluid are:
• Base Oil: Only low toxic base oil should be used as approved by the
authorities (such as the DTI in the UK). This is the external emulsion phase.
• Water: Internal emulsion phase. This gives the Oil/Water Ratio (OWR), the%
of each part as a total of the liquid phase. Generally, a higher OWR is used
for drilling troublesome formations. The salinity of the water phase can be
controlled by the use of dissolved salts, usually calcium chloride. Control of
salinity in invert oil muds is necessary to "tie-up" free water molecules and
prevent any water migration between the mud and the open formation such
as shales.
41. • Emulsifier: Often divided into primary and secondary emulsifiers. These act
at the interface between the oil and the water droplets. Emulsifier levels are
held in excess to act against possible water and solid contamination
• Wetting Agent: This is a high concentration emulsifier used especially in high
density fluids to oil wet all the solids. If solids become water wet they will
not be suspended in the fluid, and would settle out of the system.
• Organophillic Clay: These are clays treated to react and hydrate in the
presence of oil. They react with oil to give both suspension and viscosity
characteristics
• Lime: Lime is the primary ingredient necessary for reaction with the
emulsifiers to develop the oil water interface. It is also useful in combating
acidic gases such as CO2 and H2S. The concentration of lime is usually held
in excess of 2 to 6 ppb, depending on conditions.
42. PSEUDO OIL BASED MUD:
• To help in the battle against the environmental problem of low toxicity oil
based muds and their low biodegradability, developments have been made
in producing a biodegradable synthetic base oil.
• A system which uses synthetic base oil is called a Pseudo Oil Based Mud
(SOB) and is designed to behave as close as possible to low toxic oil based
mud (LTOBM).
• It is built in a fashion akin to normal oil based fluids, utilising modified
emulsifiers.
43. GAS BASED FLUIDS:
There are four main types of gas based fluids:
1. Air 2. Mist 3. Foam 4. Aerated Drilling Fluid
These are not common systems as they have limited applications such as
the drilling of depleted reservoirs or aquifers where normal mud weights
would cause severe loss circulation.
In the case of air the maximum depth drillable is currently about 6-8,000 ft
because of the capabilities of the available compressors.
Water if present in the formation is very detrimental to the use of gas-based
muds as their properties tends to break down in the presence of water.
The advantages of drilling with air in the circulating system are: higher
penetration rates; better hole cleaning; and less formation damage.
However, there are also two important disadvantages: air cannot support
the sides of the borehole and air cannot exert enough pressure to prevent
formation fluids entering the borehole.
44. Drilling Fluid Properties
• The properties of a drilling fluid can be analysed by its physical and chemical
attributes.
• The major properties of the fluid should be measured and reported daily in
the drilling morning report.
• Each mud property contributes to the character of the fluid and must be
monitored regularly to show trends, which can be used to ascertain what is
happening to the mud whilst drilling.
• There are many tests a fluid can have; the major ones are explained below.
45. MUD WEIGHT OR MUD DENSITY:
• Unit: pounds per gallon (ppg or lb/gal).
• Alternatives:Specific Gravity SG (g/cm3),Kpa/m, psi/ft
• ppg = sg x8.33
= KPa/m x 1.176
= psi/ft x 0.052
Apparatus: Mud balance,
or where gases may be entrapped in the mud due to high weights or thick
mud, then a Pressure Balance should be used.
Each should be calibrated at the start of the job to weigh 8.33 ppg with fresh
water.
A cup is filled with a sample of mud and is then balanced on the mud balance
which is calibrated to read mud weight directly.
46. • Mud Balance
• Additives: Increasing mud density should only be done with additions of a
weight material, e.g. barytes, haematite or acid soluble, calcium carbonate,
and not through build up of drilled solids.
• Decreasing mud density should only be done by dilution and acceptable
solids control practices.
• Weight increase using barytes
49. Volume increase using Barytes
• where
• X = No of 100 lbs sacks per 100 bbls of mud
• V = No of bbls increase per 100 bbls of mud
• W1 = Initial mud weight (ppg)
• W2 = Desired mud weight (ppg)
50. VISCOSITY
Viscosity is a measure of the internal
resistance of a fluid to flow)).
Two common methods are used on the rig to
measure viscosity:
1. Marsh funnel
2. Rotational viscometer
1- Funnel Viscosity
Apparent Viscosity (vis) is the measured times it
takes for one quart of mud to gravity feed through
a hole of a specific diameter.
51. FUNNEL VISCOSITY:
Unit: Seconds per quart (sec/qt).
Alternatives: Seconds per litre (sec/lt).
Apparatus: Marsh Funnel. This is usually calibrated to read 26 ± 0.5 seconds
when testing with fresh water.
• The March Funnel is a simple device used for the routine monitoring of the
viscosity, and should be performed alongside the mud weight check.
• Marsh funnel readings are affected by mud weight, solids content and
temperature.
• The value from the Marsh funnel should only be used for comparison
purposes and for monitoring trends.
54. viscosity
2- Multi Speed rheometr
Relates viscosity to shear rate and
shear stress.
i. Newtonian fluids
ii. Non Newtonian fluids
55.
56. PLASTIC VISCOSITY (PV):
• Apparatus: Viscometer or rheometer is a device used to measure the
viscosity and yield point of mud . A sample of mud is placed in a slurry cup
and rotation of a sleeve in the mud gives readings which can be
mathematically converted into plastic viscosity (PV) and yield point (YP).
• Multi-speed rheometer are recommended whenever possible since readings
can be obtained at 600,300,200,100,6 and 3 rpm. PV (in cP) is measured by
taking the difference between the dial readings taken at the two highest
speeds of 600 rpm and 300 rpm
• PV = θ600 - θ300
57. Plastic viscosity (PV)
is that part of flow resistance in a mud caused primarily by the friction
between the suspended particles and by the viscosity of the continuous
liquid phase. i.e. it is a representation of the concentration, size and
shape of the solid particles.
Yield point (YP)
is a measurement under flowing conditions of the forces in the
mud which cause gel structure to develop when the mud is at rest.
58. Bingham Plastic Fluids
((Reology in Bingham model concerned with PV & YP))
• PV = 600 - 300
• YP = 300 – PV
• It is more accurate in Oil Base Mud than in Water base mud.
• True Yield Point
• yt = ¾ yB
• Apparent Viscosity
• AF = ½ 600
59.
60. Power Law Fluids
• It allows for more plastic or pseudo – fluid behavior.
• Power law slip velocity is generally less than Bingham one.
• Calculating slip velocity by Bingham provide adequate hole cleaning
• More accurate in water base mud.
61. Power Law Model Fluids
n = 3.32 log (600 / 300)
k = 300 / 511n
62.
63.
64.
65.
66. YIELD POINT:
• Unit: lbf/100sq ft
• Alternatives:Pascals (Pa) = lbs/100sq.ft x 0.48
Apparatus: Same equipment as used for measurement of plastic viscosity.
Yield Point (YP) is calculated from the following:
• YP = θ300 – PV (7.4)
• Both PV and YP are mathematical values which can be used for calculating
the pressure loss in the circulating system
• When plastic viscosity rises, this is usually an indication that the solids
control equipment are running inefficiently.
• Ideally, the yield point should be just high enough to suspend the cuttings as
they are circulated up the annulus.
67. Gel strength
Gel strength (Gel): is a measurement under static conditions of the forces in the mud
which cause gel structure to develop when the mud is at rest.
The gel strength of the mud will provide an indication of the pressure required to
initiate flow after the mud has been static for some time.
The gel strength of the mud also provides an indication of the suspension properties
of the mud and hence its ability to suspend cuttings when the mud is stationary.
68. GEL STRENGTHS:
• Unit:Same as Yield Point.
• Alternatives: Same as Yield Point.
Apparatus: Six speed viscometer. There are two readings for gel strengths, 10
second and 10 minute with the speed of the viscometer set at 3 rpm.
The fluid must have remained static prior to each test, and the highest peak
reading will be reported.
• Applications: The gel strength quantifies the thixotropic behaviour of a fluid;
its ability to have strength when static, in order to suspend cuttings, and
flow when put under enough force. Ideally the two values of gel strength
should be close rather than progressively far apart.
69. The gel strength can be measured using the multi-rate viscometer.
After the mud has remained static for some time (10 secs) the rotor is set at
a low speed (3 rpm) and the deflection noted. This is reported as the initial
or 10 second gel.
The same procedure is repeated after the mud remains static for 10
minutes, to determine the 10 minute gel.
Both gels are measured in the same units as Yield Point (lbs/ 100ft2).
Gel strength usually appears on the mud report as two figures (e.g. 17/25).
The first being the initial gel and the second the 10 minute gel.
70. FLUID LOSS AND FILTER CAKE:
The filter cake building properties of mud can be measured by means of a filter press.
• Fluid loss: Unit: ml / 30 minutes at 100 psi (for API test) or 500 psi and BHT ( F) for high
temperature/high pressure (HTHP).
• Filter cake thickness is measured in 1 /32".
Apparatus: Both tests work on filling a cell with drilling fluid, and sealing it shut.
Inside the cell is a filter paper that has been placed between the mud and the aperture in
the cell.
Pressure is applied to the cell which forces the mud and solids through the filter paper.
The solids accumulating on he filter paper form a filter cake and the the filtrate passing
through the paper is collected in a graduated cylinder.
The mud in the cell is pressurised for 30 min and the fluid or filtrate is collected and
measured.
The filter paper is also collected, washed, then examined and the deposited filter cake is
measured.
HPHT tests with the cell put under heat are usually carried out on wells where the
temperature is greater than 200o F.
75. Applications:
The fluid loss gives a representation of the fluids interaction with the well
bore under simulated pressure and temperature conditions.
Ideally the fluid should form a thin, flexible, impermeable layer (filter cake)
against the wall and prevent fluid (filtrate) from entering the rock and
reacting with the formations.
A mud system with a low value of filtrate loss cause minimum swelling of
clays and minimum formation damage.
The filter cake should be in the region of 1 to 2 /32" and should never be
greater than 3/32", even in an HPHT test with WBM.
Filtration control additives include:
Starch
Carboxymethylcellulose (CMC)
Polyanionic Cellulose (PAC)
76. Sand Content:
• A high proportion of sand in the mud can damage the mud pumps and is
therefore undesirable.
• The percentage of sand in the mud is therefore measured regularly using a
200 mesh sieve and a graduated tube .
• The glass measuring tube is filled with mud up to the scribe line. Water is
then added up to the next scribe line. The fluids are mixed by shaking and
then poured through the sieve.
• The sand retained on the sieve should be washed thoroughly to remove and
remaining mud.
• A funnel is fitted to the top of the sieve and the sand is washed into the glass
tube by a fine spray of water.
• After allowing the sand to settle the sand content can be read off directly as
a percentage.