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.
Complete Casing Design with types of casing, casing properties, casing functions, design criteria and properties used for designing and one numerical problem
Introduction of Directional Drilling
By Syamsu Setiabudi
• Reference and Coordinates SYSTEM
• Types AND Calculation of DIRECTIONAL Well Trajectories
• Directional SURVEY & TOOLS
• DIRECTIONAL DRILLING OPERATION
• BHA BASIC DESIGN & APPLICATION
Complete Casing Design with types of casing, casing properties, casing functions, design criteria and properties used for designing and one numerical problem
Introduction of Directional Drilling
By Syamsu Setiabudi
• Reference and Coordinates SYSTEM
• Types AND Calculation of DIRECTIONAL Well Trajectories
• Directional SURVEY & TOOLS
• DIRECTIONAL DRILLING OPERATION
• BHA BASIC DESIGN & APPLICATION
This slide would teach the well control method during drilling operations, and the shut-in procedure in case of a kick. Please note that shut-in procedure may vary from site to site depending on the equipment available and the site regulations but whatever the situation, this is the general procedure for well control during drilling. Enjoy!
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.
The presentation highlights the root causes of major drilling issues such as formation pressure uncertainty, subsurface feature like mud volcanoes, major fault, poor well planning & etc. Then it elaborates on consequences of all above on examples of wellbore instability, sticking, gumbo & so on.
my presentation about kick tolerance and contain 3 videos
the reference (well drilling & construction) Hussain Rabia
and weatherford essay & videos from youtube
Presentation defines well completion as a sub-discipline of drilling operations. It introduces the various components of the well completion process. It then describes and explains basic areas of the completion process including the bottom-hole completion process, the perforation process, the upper completion with packers, tubing component equipment and devices, tubing configurations, the horizontal completions and the Christmas tree(production head)
This slide would teach the well control method during drilling operations, and the shut-in procedure in case of a kick. Please note that shut-in procedure may vary from site to site depending on the equipment available and the site regulations but whatever the situation, this is the general procedure for well control during drilling. Enjoy!
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.
The presentation highlights the root causes of major drilling issues such as formation pressure uncertainty, subsurface feature like mud volcanoes, major fault, poor well planning & etc. Then it elaborates on consequences of all above on examples of wellbore instability, sticking, gumbo & so on.
my presentation about kick tolerance and contain 3 videos
the reference (well drilling & construction) Hussain Rabia
and weatherford essay & videos from youtube
Presentation defines well completion as a sub-discipline of drilling operations. It introduces the various components of the well completion process. It then describes and explains basic areas of the completion process including the bottom-hole completion process, the perforation process, the upper completion with packers, tubing component equipment and devices, tubing configurations, the horizontal completions and the Christmas tree(production head)
PNGE 310
Class 2
1
Overbalanced Drilling
• Most common type of Oil & Gas drilling
• Drilling with Fluid filled hole
• Hydrostatic pressure > formation pressure
• 𝑃ℎ = 0.052 ∗ 𝑀𝑊 ∗ 𝑇𝑉𝐷 ,
• 𝑤ℎ𝑒𝑟𝑒 𝑃ℎ 𝑖𝑠 𝑡ℎ𝑒 ℎ𝑦𝑑𝑟𝑜𝑠𝑡𝑎𝑡𝑖𝑐 𝑝𝑟𝑒𝑠𝑠𝑢𝑟𝑒 𝑖𝑛 𝑝𝑠𝑖,
• 𝑀𝑊 𝑖𝑠 𝑡ℎ𝑒 𝑓𝑙𝑢𝑖𝑑 𝑑𝑒𝑛𝑠𝑖𝑡𝑦 𝑖𝑛 𝑝𝑝𝑔 (
𝑙𝑏
𝑔𝑎𝑙
),𝑎𝑛𝑑
• 𝑇𝑉𝐷 𝑖𝑠 𝑡ℎ𝑒 𝑡𝑟𝑢𝑒 𝑣𝑒𝑟𝑡𝑖𝑐𝑎𝑙 𝑑𝑒𝑝𝑡ℎ 𝑖𝑛 𝑓𝑡
• Freshwater: 8.33 ppg
• Brine: ~8.5- 9.0 ppg
• Muds: ~8.5- 20 ppg
• Water Based Mud
• Diesel Based Mud
• Synthetic Oil Based Mud
2
Overbalanced Drilling:
Rig Components
3
1. Crown Block
2. Cat Line (Hoist)
3. Drill Line
4. Monkey Board
5. Traveling Block (Hook)
6. Top Drive
7. Derrick (Mast)
8. Drill Pipe, Elevators, Bails
9. Doghouse, Drillers Cabin (DS, ODS)
10. BOP (Stack)
11. Rig Water
12. Cable Tray (Festoon)
13. Generators (Gens)
14. Rig Fuel
15. Electric House (VFD)
16. Mud Pumps
17. Bulk Mud Storage
18. Mud Pits
19. Earth Pit (Solids Control)
20. Separator (Gas Buster)
21. Shakers
22. Choke Manifold
23. V-Door
24. Pipe Racks
25. Accumulator
Crown Block
• An assembly of sheaves or pulleys mounted on beams at the
top of the derrick. The drilling line is run over the sheaves
down to the hoisting drum.
4
Traveling Block
• An arrangement of pulleys or sheaves through which drilling
cable is reeved, which moves up or down in the derrick or
mast.
5
Top Drive
• The top drive rotates the drill string without the use of a kelly
and rotary table. The top drive is operated from a control
console on the rig floor or from joysticks in the drillers house.
6
Bails
• Large steel tubular used to connect the elevators to the top
drive. Used when picking up pipe, tripping drill pipe, or
running casing.
7
Elevators
• A set of clamps that grips a stand, or column, of casing, tubing,
drill pipe, or sucker rods, so the stand can be raised or lowered
into the hole.
8
Drawworks
• The hoisting mechanism on a drilling rig. It is essentially a
large winch that spools off or takes in the drilling line which
raises or lowers the traveling blocks
9
Catwalk
• Equipment where pipe is laid to be lifted to the rig floor by the
catline or by an air hoist. Can be automated by hydraulics.
• https://www.youtube.com/watch?v=Nzn2m_wqzlM
10
https://www.youtube.com/watch?v=Nzn2m_wqzlM
Drill String Design
• Drill String Components:
• Bit
• Drill Collars
• Tapered/ Non-Tapered
• Drill Pipe
• Tapered/ Non-Tapered
11
Buoyancy
• Buoyancy Factor is the factor that is used to compensate loss
of weight due to immersion in drilling fluid, 0-1.0
• 65.44ppg is the weight of steel
12
𝐵𝐹 = 1 −
𝜌𝑓𝑙𝑢𝑖𝑑
𝜌𝑝𝑖𝑝𝑒
𝑜𝑟
65.44 − 𝑀𝑊[𝑝𝑝𝑔]
65.44
Drill String Design Checklist
1. Air Weight Calculations
2. Tapered/Non-Tapered DC Calculations
3. Stiffness Ratio
4. Bending Strength Ratio
5. DC Make-Up Torque
6. Drill Pipe Information & Design
7. Margin of Pull (MOP) also called Ov
Design analysis of Cotter joint used in piston rod and crosshead a.pptx138HemangiAhire
Design analysis of Cotter joint
used in piston rod and crosshead
1.Abstract
2.Introduction
3.Literature survey
4.Design of cotter joint
5.Cotter joint to connect piston rod and crosshead
6.Example problem statement
7.3d modelling of cotter joint
8.Analysis of cotter joint
9.Result and discussion
10.Conclusion
11.Suggestion for future
12.References
Diseno en ingenieria mecanica de Shigley - 8th ---HDes
descarga el contenido completo de aqui http://paralafakyoumecanismos.blogspot.com.ar/2014/08/libro-para-mecanismos-y-elementos-de.html
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Democratizing Fuzzing at Scale by Abhishek Aryaabh.arya
Presented at NUS: Fuzzing and Software Security Summer School 2024
This keynote talks about the democratization of fuzzing at scale, highlighting the collaboration between open source communities, academia, and industry to advance the field of fuzzing. It delves into the history of fuzzing, the development of scalable fuzzing platforms, and the empowerment of community-driven research. The talk will further discuss recent advancements leveraging AI/ML and offer insights into the future evolution of the fuzzing landscape.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Event Management System Vb Net Project Report.pdfKamal Acharya
In present era, the scopes of information technology growing with a very fast .We do not see any are untouched from this industry. The scope of information technology has become wider includes: Business and industry. Household Business, Communication, Education, Entertainment, Science, Medicine, Engineering, Distance Learning, Weather Forecasting. Carrier Searching and so on.
My project named “Event Management System” is software that store and maintained all events coordinated in college. It also helpful to print related reports. My project will help to record the events coordinated by faculties with their Name, Event subject, date & details in an efficient & effective ways.
In my system we have to make a system by which a user can record all events coordinated by a particular faculty. In our proposed system some more featured are added which differs it from the existing system such as security.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
4. Introduction
• The drillstring design is the mechanical
linkage connecting the drillbit at the bottom of
the hole to the rotary drive system on the
surface.
• The drillstring has several functions:
- transmit rotation to the drillbit.
- exerts weight on bits (WOB)
- guides & controls trajectory of the bit
- allows fluid circulation
4
6. Drill Pipe Selection
Grade Minimum Yield
Strength, psi
Letter Designation Alternate
Designation
D D-55 55,000
E E-75 75,000
X X-95 95,000
G G-105 105,000
S S-135 135,000
• Only grade E, G and S are actually used in oilwell drilling.
• API RP7G established guidelines for Drill Pipe as follows:
- New = no wear, never been used
- Premium = uniform wear, 80% wall thickness of new pipe
- Class 2 = 65% wall thickness of new pipe
- Class 3 = 55% wall thickness of new pipe
6
Table 1: DP grade and yield strength
7. Tool Joints
• Tool joints are screw-type connectors that
join the individual joints of drillpipe.
• All API tool joints have minimum a yield
strength of 120,000 psi.
7
8. Washout in Drillstrings
• Tool joint failure is one of the main causes of
fishing jobs in drilling industry. This failure is
due entirely to the joint threads not holding
or not being made properly.
8
Figure 2: Make Up Torque
9. Washout in Drillstrings
• Washout can also develop due to cracks develop
within drill pipe due to severe drilling vibrations.
• Washout are usually detected by a decrease in the
standpipe pressure, between 100 – 300 psi over 5 –
15 minutes.
• The life of tool joints can be tripled if the joints if
hardfaced with composites of steel and tungsteen
carbide.
9
10. Approximate Weight of DP
and Tool Joint
• Nominal weight of DP is always less than the actual
weight of DP and tool joint because of the extra
weight added by tool joint and due to extra metal
added at the pipe ends to increase the pipe
thickness.
10
Figure 3: Tool joint dimension
11. Approximate Weight of DP
and Tool Joint
• Calculations of approximate weight of tool joint and DP:
a)
b)
Approximate adjusted weight of DP = Plain end weight + upset weight
29.4
( 2 2
)
Approximate adjusted weight of tool jo int = 0.222
x L D -
d
x ( D 3 D 3 ) TE x d 2
x ( D DTE
) + - - -
0.167 0.501
Where :
L = combined length of pin and box (in)
D = outside diameter of pin (in)
d = inside diameter of pin (in)
DTE = diameter of box at elevator upset (in) 11
12. Approximate Weight of DP
and Tool Joint
c)
Approximate adjusted weight of DP assembly
approx adjusted wt DP x approx wt tool jo
= +
. . 29.4 . . int
where,
12
tool jo adjusted length
+
29.4 int
( tool jo int adjusted length = L + 2.253 x D -
DTE ) ft
12
14. Approximate Weight of DP
and Tool Joint
• Example
calculate the approximate weight of tool joint and DP assembly for 5 in
OD, 19.5 lb/ft Grade E DP having a 6.375 in OD, 3.5 in ID. With NC50
tool joint. Assume the pipe to be internally-externally upset (IEU) and the
weight increased due to upsetting to be 8.6 lb.
• Solution
Referring to Table 2, NC50, 6.375 in OD, 3.5 in ID tool joint for 19.5 lb/ft
nominal weight DP is available in grade X95
Thus L = 17 in ; DTE = 5.125 in
D = 6.375 in ; and d = 3.5 in
14
15. Approximate Weight of DP
and Tool Joint
a) Approximate adjusted weight of Tool Joint
= 0.222 x 17 6.3752 - 3.52 + 0.167 x 6.3753 - 5.1253 - 0.501 x 3.52 x
6.375 -
5.125
=
b). Approximate adjusted weight of Drill Pipe
15
= 0.222 x L (D2 - d 2 )+ 0.167 x (D3 - D3TE )- 0.501 x d 2 x (D- DTE )
( ) ( ) ( )
lb
120.27
= plain - end weight + upset weight
29.4
( ) 29.4
= p 2 - 2 x x +
=17.93+0.293=18.22 lb / ft
489.5 8.6
5 4.276 1
4
144
16. Approximate Weight of DP
and Tool Joint
Adjusted length of tool joint:
= L + 2.253 x D - DTE = 17 + 2.253 x 6.375 - 5.125
=
c) Hence, approximate weight of tool joint and DP assembly :
16
( ) ( ) 1.651
12
12
x 21.2 lb / ft
18.22 120.27 =
+
1.651 29.4
=
17. Drill Collar (DC) Selection
• There are two types of DC :
- Slick DC
- Spiral DC
• In areas where differential
sticking is a possibility
spiral DC should be used in
order to minimize contact
area with formation.
Figure 4:Type of Drill Collars 17
19. Procedure for Selecting DC
1) Determine the Buoyancy Factor (BF) of the mud weight:
MW = mud weight, ppg
65.5 = weight of a gallon of steel, ppg
BF =1- MW
2) Calculate the required collar length to achieve desired WOB:
WOB = weight on bit, lbf (x1000)
Wdc = DC weight in air, lb/ft
0.85 = safety factor
BF = buoyancy factor, dimensionless
Length x BF xW
3) For directional well:
I = well inclination
19
65.5
dc
DC WOB
0.85
=
DC DC Length vertical Length =
cos
I
20. Bending Strength Ratio (BSR)
• Bending strength ratio defined as the ratio of
relative stiffness of the box to the pin for a
given connection.
• Large OD drill collars provide greater
stiffness and reduce hole deviation problem.
20
21. Stiffness Ratio (SR)
• Stiffness ratio define as follows:
SR = Section modulus of lower section tube/section
modulus of upper section tube
SR = OD OD -
ID
• From field experience, a balance BHA should have:
- SR = 5.5 for routine drilling
- SR = 3.5 for severe drilling or significant failure
rate experience
21
( )
( 2
2 )
2
1 2
2
1
2
2 1
OD OD -
ID
22. Heavy Weight Drill Pipe (HWDP)
• HWDP has the same OD
of a standard DP but with
much reduce inside
diameter (usually 3”)
22
Figure 5:Type of HWDP
23. Stabilizer
• Stabilizer tools are
places above the drill
bit and along the BHA
to control hole
deviation, dogleg
severity and prevent
differential sticking.
• There are two types of
stabilizer:
– rotating stabilizer
– non rotating
stabilizer
23
Figure 6:Type of Stabilizer
24. Standard BHA Configuration
• There are five types of BHA configuration:
1. Pendulum assembly
2. Packed bottom hole assembly
3. Rotary build assembly
4. Steerable assembly
5. Mud motor and bent sub assembly
24
25. Drillstring Design Criteria
• The criteria used in drillstring design are :
- Collapse
- Tension
- Dogleg Severity Analysis
25
26. Collapse Design
• The criteria to be used as worst case for the
collapse design of DP is typically a DST. The
maximum collapse pressure should be determined
for an evacuated string, with mud hydrostatic
pressure acting on the outside of the DP.
• A design factor is used in constructing the collapse
design line. The design factor to be used for this full
evacuation scenario is 1.0.
26
27. Collapse Calculation
1. DST (Drill Stem Test)
P L xr1 L Y xr2 c
= - -
• Where:
- Pc = collapse pressure (psia)
- Y = depth to fluid inside DP (f)
- L = total depth of well (ft)
- r1 = fluid density outside DP (ppg)
- r1 = fluid density inside DP (ppg)
27
( )
19.251 19.251
28. Collapse Calculation
2. Design Factor in Collapse
DF = collapse resis ce of Drillpipe
a DF of 1.125 is normally used
28
( )
tan
collapse pressure Pc
29. Tension Design
• The tension load is evaluated using the
maximum load concept. Buoyancy is included
in the design to represent realistic drilling
condition.
• The tension design is established by
consideration of the following :
- tensile force
- design factor
- slip crushing design 29
30. Tension Design
(Tensile Force)
Weight Carried
• The greatest tension (P) on drillstring
occurs at top joint at the maximum
drilled depth.
P = [(Ldp xWdp + Ldc xWdc )]x BF
Where :
Ldp = length of DP per foot
Wdp = weight of DP per unit length
Ldc = length of DC per foot
Wdc = weight of DC per unit length
BF = Buoyancy Factor 30
31. Tension Design
(Tensile Force)
• The drillstring should not be designed to its
maximum yield strength to prevent the DP
from yielding and deforming. At yield, the DP
will have:
– Deformation made up of elastic and plastic (permanent)
deformation.
– Permanent elongation.
– Permanent bend & it may be difficult to keep it straight.
31
32. Tension Design
(Tensile Force)
• To prevent this, API recommends that the use of maximum
allowable design load (Pa), given by :
Where :
- Pa = max. allowable design load in tension, lb
- Pt = theoretical yield strength from API tables, lb
- 0.9 = a constant relating proportional limit to yield strength
32
Pa = 0.9 x Pt
33. Tension Design
(Tensile Force)
• From above (tensile force) equation, we
obtain:
MOP = Pa – P
DF = Pa / P
where :
MOP = margin of overpull, lbs
DF = design factor, dimensionless
33
34. Dogleg Severity Analysis
• The most common DP failure is
fatigue wear. Fatigue is
tendency of material to fracture
under repeated cyclic stress
and chemical attack.
• A DP fatigue wear generally
occurs because the outer wall
of the pipe in a dogleg is
stretched resulting in additional
tension loads.
34
35. Dogleg Severity Analysis
• The maximum possible dogleg severity for
fatigue damage considerations can be
calculated using the following formula:
35
x KL
KL
MaxD x b
ED
s
432,000 s tanh
p
=