The document discusses safety valve settings and requirements according to ASME code. It describes the parts and operation of safety valves including the lifting, blowback, adjusting rings, and testing procedures. It states that safety valves must be set so that pressure does not rise more than 6% above the maximum allowable working pressure and the total relieving capacity of all valves cannot be more than 10% of the highest pressure setting. It also outlines code requirements for minimum number of safety valves depending on boiler size.
The document discusses various boiler mountings, which are crucial components that allow boilers to operate safely. It describes key mountings like safety valves, water level indicators, pressure gauges, and their functions. Safety valves in particular are discussed in depth, including their construction, types, setting pressures, testing procedures, and regulations. Maintaining proper boiler mountings is important for safety and optimal boiler performance.
This document provides information on various types of safety valves, their purpose, construction, operation, maintenance and testing procedures. It discusses safety valves, relief valves, safety relief valves, vacuum relief valves and their characteristics. The document also outlines requirements for safety valves according to regulations, general sizing guidelines, and procedures for dismantling, overhauling, assembling, testing, maintenance and erection of safety valves.
This document summarizes the key components of an anesthesia workstation's high pressure system. It describes the hanger yoke assembly, which orients and supports gas cylinders and provides a gas-tight seal. It also discusses the pin index safety system, cylinder pressure indicators, check valve assemblies, and pressure regulators. The pressure regulators receive gases from cylinders at high pressures and reduce the pressure to a lower, more constant pressure suitable for use in the anesthesia machine. Safety features like relief valves are also included to prevent overpressurization.
This document provides information about the basic components and functioning of an anaesthesia machine. It discusses the key components of the machine's pneumatic and electrical systems. The pneumatic system includes the high pressure, intermediate pressure and low pressure systems which are responsible for delivering precisely controlled gas mixtures from pressurized cylinders or central pipelines. The electrical components power and monitor the machine. The document also provides details on cylinders, pressure regulators and other individual parts that make up the overall anaesthesia machine.
- The document discusses sizing pressure safety valves (PSVs) for oil and gas facilities.
- It covers PSV types, causes of chattering, and outlines the step-by-step process for sizing calculations including developing relief scenarios, determining required relief areas, and selecting valve sizes.
- Relief scenarios considered include blocked outlets, thermal expansion, tube rupture, gas blow-by, inlet valve failure, and exterior fires. Relief calculations involve assessing single-phase, two-phase, and transient relief situations.
The document discusses sizing calculations for pressure safety valves (PSVs). It begins with introductions to relief systems, definitions of key terms like set pressure and accumulation. It then describes different types of PSVs and issues like chattering. The document outlines the steps for sizing calculations, which include developing a process safety diagram and relief scenarios. It provides examples of relief scenarios like blocked outlet, thermal expansion, and tube rupture. The goal of the document is to provide guidance on properly performing PSV sizing calculations.
The document discusses sizing calculations for pressure safety valves (PSVs). It begins with introductions to relief systems, how overpressure develops, and definitions of key terms. It then covers different types of PSVs and the problem of chatter. The document outlines the steps for sizing calculations, which include developing process safety diagrams and relief scenarios. It provides examples of relief scenarios for different equipment.
The document discusses various boiler mountings, which are crucial components that allow boilers to operate safely. It describes key mountings like safety valves, water level indicators, pressure gauges, and their functions. Safety valves in particular are discussed in depth, including their construction, types, setting pressures, testing procedures, and regulations. Maintaining proper boiler mountings is important for safety and optimal boiler performance.
This document provides information on various types of safety valves, their purpose, construction, operation, maintenance and testing procedures. It discusses safety valves, relief valves, safety relief valves, vacuum relief valves and their characteristics. The document also outlines requirements for safety valves according to regulations, general sizing guidelines, and procedures for dismantling, overhauling, assembling, testing, maintenance and erection of safety valves.
This document summarizes the key components of an anesthesia workstation's high pressure system. It describes the hanger yoke assembly, which orients and supports gas cylinders and provides a gas-tight seal. It also discusses the pin index safety system, cylinder pressure indicators, check valve assemblies, and pressure regulators. The pressure regulators receive gases from cylinders at high pressures and reduce the pressure to a lower, more constant pressure suitable for use in the anesthesia machine. Safety features like relief valves are also included to prevent overpressurization.
This document provides information about the basic components and functioning of an anaesthesia machine. It discusses the key components of the machine's pneumatic and electrical systems. The pneumatic system includes the high pressure, intermediate pressure and low pressure systems which are responsible for delivering precisely controlled gas mixtures from pressurized cylinders or central pipelines. The electrical components power and monitor the machine. The document also provides details on cylinders, pressure regulators and other individual parts that make up the overall anaesthesia machine.
- The document discusses sizing pressure safety valves (PSVs) for oil and gas facilities.
- It covers PSV types, causes of chattering, and outlines the step-by-step process for sizing calculations including developing relief scenarios, determining required relief areas, and selecting valve sizes.
- Relief scenarios considered include blocked outlets, thermal expansion, tube rupture, gas blow-by, inlet valve failure, and exterior fires. Relief calculations involve assessing single-phase, two-phase, and transient relief situations.
The document discusses sizing calculations for pressure safety valves (PSVs). It begins with introductions to relief systems, definitions of key terms like set pressure and accumulation. It then describes different types of PSVs and issues like chattering. The document outlines the steps for sizing calculations, which include developing a process safety diagram and relief scenarios. It provides examples of relief scenarios like blocked outlet, thermal expansion, and tube rupture. The goal of the document is to provide guidance on properly performing PSV sizing calculations.
The document discusses sizing calculations for pressure safety valves (PSVs). It begins with introductions to relief systems, how overpressure develops, and definitions of key terms. It then covers different types of PSVs and the problem of chatter. The document outlines the steps for sizing calculations, which include developing process safety diagrams and relief scenarios. It provides examples of relief scenarios for different equipment.
The document discusses breather valves, which are relief valves used to protect storage tanks from excessive pressure or vacuum. It covers how breather valves work by allowing gas to enter or exit the tank as needed to equalize pressure. The proper installation of breather valves at the top of tanks is also discussed. Key specifications for selecting an appropriate breather valve include temperature and pressure ratings, body size, and material compatibility. Breather valves provide advantages like protecting tank contents, reducing corrosion and emissions, and ensuring safety during pumping operations.
Pressure control valves are used in hydraulic systems to control actuator force by regulating system pressure levels. They perform functions like limiting maximum pressure, regulating pressure in circuits, unloading pressure, and assisting sequential operation of actuators. Common types include pressure relief valves, pressure reducing valves, unloading valves, counterbalance valves, and pressure sequence valves. Pressure relief valves protect systems from excess pressure by providing an alternate flow path. Pressure reducing valves maintain reduced pressures in parts of circuits.
The document discusses how to test the low-pressure circuit of an anesthesia machine. It describes how leaks can occur and methods to test for leaks, including positive and negative pressure leak tests. It emphasizes that machines with check valves must use a negative pressure test. Several components are tested, including the vaporizers, flow tubes, and check valves. Proper testing of the low-pressure circuit is important to ensure no leaks that could cause hypoxia or patient awareness.
The document provides instructions for operating a steam turbine. It discusses startup procedures like charging the steam line, operating cooling water and lube oil systems, building vacuum in the condenser, and rolling the turbine to full speed. It also describes shutdown procedures and checklists. Potential emergency situations for the turbine like overspeed, lube oil failure, high vibration, and fires are reviewed. The document is an operating manual for a Siemens SST300 C-160 steam turbine with technical specifications provided.
The document summarizes different types of pressure control valves used in hydraulic systems. It describes pressure relief valves, pressure reducing valves, unloading valves, counterbalance valves, and pressure sequence valves. Each type of valve is explained in terms of its working, symbol, and purpose of controlling pressure in hydraulic circuits. Compound versions of some valves are also discussed.
The document discusses the components and functioning of an anaesthesia work station's high pressure system. It describes the key components including gas cylinders, hanger yokes, cylinder pressure indicators, and pressure regulators. Gas cylinders contain medical gases at high pressure and have valves, handles, pressure relief devices, and markings. Hanger yokes orient and secure cylinders, providing a gas-tight seal. Cylinder pressure indicators display the pressure level in cylinders. Pressure regulators reduce the high cylinder pressure to a lower, constant pressure suitable for use in the anaesthesia machine.
1. Hydraulic systems typically operate at higher pressures than pneumatic systems and are suitable for very high loads, while pneumatic systems are generally used for lower pressures and forces.
2. Hydraulic components like cylinders and valves tend to be more expensive than similar pneumatic components.
3. Pneumatic systems use compressed air and flexible tubing, while hydraulic systems use pressurized liquids and metal tubing to withstand higher pressures.
Oxygen MANUFACTRE STORAGE PREPERATION AND CLINICAL ASPECTDr.RMLIMS lucknow
Oxygen is produced primarily through two main methods - fractional distillation of air and pressure swing absorption. It is stored in large bulk systems or compressed gas cylinders. Cylinders come in various standardized sizes and have safety features like pressure relief valves and color coding. Oxygen is delivered to patients through devices like nasal cannulas, masks, or venturi masks which mix oxygen with air to precisely control the fraction of inspired oxygen. While oxygen therapy is useful for treating hypoxemia, high concentrations over long periods can cause toxicity issues like pulmonary fibrosis or retinopathy of prematurity in newborns.
Valves classification and description (1).pdfssuser2dd2111
This document provides an overview of different types of valves, including their functions and key components. It discusses valves that start and stop flow, such as gate, ball, and plug valves. It also covers valves that regulate flow, like globe and butterfly valves. The document describes other valve types like check valves, relief valves, and actuated valves. It provides details on valve materials, installation, handling, and markings.
Control valves are important elements in process control systems that regulate fluid flow. They function by opening, closing, or partially obstructing passageways to start and stop flow, vary the amount of flow, control flow direction, and regulate downstream pressure. Control valves manipulate flowing fluids like gas, steam, water, or chemicals to compensate for disturbances and keep process variables at the set point. Process plants use thousands of control loops networked together, with each loop using a final control element like a control valve to keep important variables like pressure, flow, or temperature within required ranges.
Starting air system explosions can occur if oil accumulates in air receivers or lines and is ignited by high pressure air during engine starting. The ignition source is typically hot gases from a leaking starting air valve or fuel leaking into cylinders when stopped. Research concludes explosions are mainly due to autoignition of oil deposits in manifolds from compressed air heating to over 400°C. Risks can be minimized by maintaining clean air systems, fittings, valves, and following maintenance procedures.
The document discusses pressure relief devices. It covers objectives which include understanding relief events, pressure relief devices, codes and standards, terminology, types of pressure relief valves, sizing, rupture disks, and inspection/testing. It describes relief events as processes to prevent overpressure. Pressure relief devices include pressure relief valves, rupture disks, and pressure/vacuum relief valves, which safeguard against over/under pressure hazards. Codes and standards for selection and sizing are also discussed.
Gas Lift Optimization and Troubleshooting Bailey LeRoux
This document provides an overview of gas-lift optimization and troubleshooting. It discusses identifying underperforming wells using metrics like the well performance factor and target injection differential. It then covers optimizing wells by adjusting injection gas rates, removing surface restrictions, redesigning the system, and adding secondary lift. Common inlet, outlet, and downhole problems are outlined along with tests and adjustments to address issues. Tuning the well for continuous flow is also described. Finally, tools for surface and subsurface data collection to aid in troubleshooting are listed.
Valves control the flow of fluids through piping systems and come in many types for different applications. Valves are either on-off valves that completely stop or start flow, or control valves that can partially restrict flow to regulate it. Common on-off valves include gate, ball, plug, and knife valves. Control valves include globe, butterfly, and diaphragm valves. Valve selection depends on factors like pressure, temperature, fluid chemistry and the valve's intended function in the system. Proper installation, handling, and maintenance of valves is important for safety and performance.
This document provides installation and maintenance instructions for a proportional thermostatic mixing valve. It includes:
1) An overview of the valve specifications and recommended tools.
2) Step-by-step instructions for roughing-in the valve connections and installing it in the water supply lines.
3) Details on setting the temperature via the handwheel, optional methods for locking in a temperature range, and calibrating or cleaning the valve.
4) Contact information for questions.
Refrigeration and air conditioning (gtu)virajpatel204
The thermostatic expansion valve (TEV) is designed to maintain a constant evaporator pressure or superheat by controlling the flow of refrigerant into the evaporator. It operates using a needle and seat that opens and closes based on three pressures - evaporator pressure and spring pressure work to close the valve, while bulb pressure works to open the valve. The main components of a TEV are the valve body, diaphragm, needle and seat, and spring. The diaphragm and needle control refrigerant flow in response to these pressures.
This document provides an overview of early sizing considerations for pressure safety valves (PSVs). It defines important terminology related to PSVs and describes the types and operating principles of conventional, balanced bellow, and pilot-operated PSVs. The document outlines the procedure for early PSV sizing, including identifying capacity requirements, applicable standards, and inter-discipline interfaces. It also notes lessons learned regarding material selection and potential failure modes of bellow-type PSVs.
This document provides an overview of early sizing considerations for pressure safety valves (PSVs). It discusses important terminologies, types of PSVs, sizing basis, applicable standards, and the early sizing procedure. The procedure involves selecting possible orifice areas to meet capacity requirements. The objectives of early sizing are to remove holds in piping and instrumentation diagrams and allow early release of piping designs. The document also discusses inter-discipline interfaces, lessons learned, and quality management system documents related to PSV sizing.
The document discusses breather valves, which are relief valves used to protect storage tanks from excessive pressure or vacuum. It covers how breather valves work by allowing gas to enter or exit the tank as needed to equalize pressure. The proper installation of breather valves at the top of tanks is also discussed. Key specifications for selecting an appropriate breather valve include temperature and pressure ratings, body size, and material compatibility. Breather valves provide advantages like protecting tank contents, reducing corrosion and emissions, and ensuring safety during pumping operations.
Pressure control valves are used in hydraulic systems to control actuator force by regulating system pressure levels. They perform functions like limiting maximum pressure, regulating pressure in circuits, unloading pressure, and assisting sequential operation of actuators. Common types include pressure relief valves, pressure reducing valves, unloading valves, counterbalance valves, and pressure sequence valves. Pressure relief valves protect systems from excess pressure by providing an alternate flow path. Pressure reducing valves maintain reduced pressures in parts of circuits.
The document discusses how to test the low-pressure circuit of an anesthesia machine. It describes how leaks can occur and methods to test for leaks, including positive and negative pressure leak tests. It emphasizes that machines with check valves must use a negative pressure test. Several components are tested, including the vaporizers, flow tubes, and check valves. Proper testing of the low-pressure circuit is important to ensure no leaks that could cause hypoxia or patient awareness.
The document provides instructions for operating a steam turbine. It discusses startup procedures like charging the steam line, operating cooling water and lube oil systems, building vacuum in the condenser, and rolling the turbine to full speed. It also describes shutdown procedures and checklists. Potential emergency situations for the turbine like overspeed, lube oil failure, high vibration, and fires are reviewed. The document is an operating manual for a Siemens SST300 C-160 steam turbine with technical specifications provided.
The document summarizes different types of pressure control valves used in hydraulic systems. It describes pressure relief valves, pressure reducing valves, unloading valves, counterbalance valves, and pressure sequence valves. Each type of valve is explained in terms of its working, symbol, and purpose of controlling pressure in hydraulic circuits. Compound versions of some valves are also discussed.
The document discusses the components and functioning of an anaesthesia work station's high pressure system. It describes the key components including gas cylinders, hanger yokes, cylinder pressure indicators, and pressure regulators. Gas cylinders contain medical gases at high pressure and have valves, handles, pressure relief devices, and markings. Hanger yokes orient and secure cylinders, providing a gas-tight seal. Cylinder pressure indicators display the pressure level in cylinders. Pressure regulators reduce the high cylinder pressure to a lower, constant pressure suitable for use in the anaesthesia machine.
1. Hydraulic systems typically operate at higher pressures than pneumatic systems and are suitable for very high loads, while pneumatic systems are generally used for lower pressures and forces.
2. Hydraulic components like cylinders and valves tend to be more expensive than similar pneumatic components.
3. Pneumatic systems use compressed air and flexible tubing, while hydraulic systems use pressurized liquids and metal tubing to withstand higher pressures.
Oxygen MANUFACTRE STORAGE PREPERATION AND CLINICAL ASPECTDr.RMLIMS lucknow
Oxygen is produced primarily through two main methods - fractional distillation of air and pressure swing absorption. It is stored in large bulk systems or compressed gas cylinders. Cylinders come in various standardized sizes and have safety features like pressure relief valves and color coding. Oxygen is delivered to patients through devices like nasal cannulas, masks, or venturi masks which mix oxygen with air to precisely control the fraction of inspired oxygen. While oxygen therapy is useful for treating hypoxemia, high concentrations over long periods can cause toxicity issues like pulmonary fibrosis or retinopathy of prematurity in newborns.
Valves classification and description (1).pdfssuser2dd2111
This document provides an overview of different types of valves, including their functions and key components. It discusses valves that start and stop flow, such as gate, ball, and plug valves. It also covers valves that regulate flow, like globe and butterfly valves. The document describes other valve types like check valves, relief valves, and actuated valves. It provides details on valve materials, installation, handling, and markings.
Control valves are important elements in process control systems that regulate fluid flow. They function by opening, closing, or partially obstructing passageways to start and stop flow, vary the amount of flow, control flow direction, and regulate downstream pressure. Control valves manipulate flowing fluids like gas, steam, water, or chemicals to compensate for disturbances and keep process variables at the set point. Process plants use thousands of control loops networked together, with each loop using a final control element like a control valve to keep important variables like pressure, flow, or temperature within required ranges.
Starting air system explosions can occur if oil accumulates in air receivers or lines and is ignited by high pressure air during engine starting. The ignition source is typically hot gases from a leaking starting air valve or fuel leaking into cylinders when stopped. Research concludes explosions are mainly due to autoignition of oil deposits in manifolds from compressed air heating to over 400°C. Risks can be minimized by maintaining clean air systems, fittings, valves, and following maintenance procedures.
The document discusses pressure relief devices. It covers objectives which include understanding relief events, pressure relief devices, codes and standards, terminology, types of pressure relief valves, sizing, rupture disks, and inspection/testing. It describes relief events as processes to prevent overpressure. Pressure relief devices include pressure relief valves, rupture disks, and pressure/vacuum relief valves, which safeguard against over/under pressure hazards. Codes and standards for selection and sizing are also discussed.
Gas Lift Optimization and Troubleshooting Bailey LeRoux
This document provides an overview of gas-lift optimization and troubleshooting. It discusses identifying underperforming wells using metrics like the well performance factor and target injection differential. It then covers optimizing wells by adjusting injection gas rates, removing surface restrictions, redesigning the system, and adding secondary lift. Common inlet, outlet, and downhole problems are outlined along with tests and adjustments to address issues. Tuning the well for continuous flow is also described. Finally, tools for surface and subsurface data collection to aid in troubleshooting are listed.
Valves control the flow of fluids through piping systems and come in many types for different applications. Valves are either on-off valves that completely stop or start flow, or control valves that can partially restrict flow to regulate it. Common on-off valves include gate, ball, plug, and knife valves. Control valves include globe, butterfly, and diaphragm valves. Valve selection depends on factors like pressure, temperature, fluid chemistry and the valve's intended function in the system. Proper installation, handling, and maintenance of valves is important for safety and performance.
This document provides installation and maintenance instructions for a proportional thermostatic mixing valve. It includes:
1) An overview of the valve specifications and recommended tools.
2) Step-by-step instructions for roughing-in the valve connections and installing it in the water supply lines.
3) Details on setting the temperature via the handwheel, optional methods for locking in a temperature range, and calibrating or cleaning the valve.
4) Contact information for questions.
Refrigeration and air conditioning (gtu)virajpatel204
The thermostatic expansion valve (TEV) is designed to maintain a constant evaporator pressure or superheat by controlling the flow of refrigerant into the evaporator. It operates using a needle and seat that opens and closes based on three pressures - evaporator pressure and spring pressure work to close the valve, while bulb pressure works to open the valve. The main components of a TEV are the valve body, diaphragm, needle and seat, and spring. The diaphragm and needle control refrigerant flow in response to these pressures.
This document provides an overview of early sizing considerations for pressure safety valves (PSVs). It defines important terminology related to PSVs and describes the types and operating principles of conventional, balanced bellow, and pilot-operated PSVs. The document outlines the procedure for early PSV sizing, including identifying capacity requirements, applicable standards, and inter-discipline interfaces. It also notes lessons learned regarding material selection and potential failure modes of bellow-type PSVs.
This document provides an overview of early sizing considerations for pressure safety valves (PSVs). It discusses important terminologies, types of PSVs, sizing basis, applicable standards, and the early sizing procedure. The procedure involves selecting possible orifice areas to meet capacity requirements. The objectives of early sizing are to remove holds in piping and instrumentation diagrams and allow early release of piping designs. The document also discusses inter-discipline interfaces, lessons learned, and quality management system documents related to PSV sizing.
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.
Optimizing Gradle Builds - Gradle DPE Tour Berlin 2024Sinan KOZAK
Sinan from the Delivery Hero mobile infrastructure engineering team shares a deep dive into performance acceleration with Gradle build cache optimizations. Sinan shares their journey into solving complex build-cache problems that affect Gradle builds. By understanding the challenges and solutions found in our journey, we aim to demonstrate the possibilities for faster builds. The case study reveals how overlapping outputs and cache misconfigurations led to significant increases in build times, especially as the project scaled up with numerous modules using Paparazzi tests. The journey from diagnosing to defeating cache issues offers invaluable lessons on maintaining cache integrity without sacrificing functionality.
Electric vehicle and photovoltaic advanced roles in enhancing the financial p...IJECEIAES
Climate change's impact on the planet forced the United Nations and governments to promote green energies and electric transportation. The deployments of photovoltaic (PV) and electric vehicle (EV) systems gained stronger momentum due to their numerous advantages over fossil fuel types. The advantages go beyond sustainability to reach financial support and stability. The work in this paper introduces the hybrid system between PV and EV to support industrial and commercial plants. This paper covers the theoretical framework of the proposed hybrid system including the required equation to complete the cost analysis when PV and EV are present. In addition, the proposed design diagram which sets the priorities and requirements of the system is presented. The proposed approach allows setup to advance their power stability, especially during power outages. The presented information supports researchers and plant owners to complete the necessary analysis while promoting the deployment of clean energy. The result of a case study that represents a dairy milk farmer supports the theoretical works and highlights its advanced benefits to existing plants. The short return on investment of the proposed approach supports the paper's novelty approach for the sustainable electrical system. In addition, the proposed system allows for an isolated power setup without the need for a transmission line which enhances the safety of the electrical network
An improved modulation technique suitable for a three level flying capacitor ...IJECEIAES
This research paper introduces an innovative modulation technique for controlling a 3-level flying capacitor multilevel inverter (FCMLI), aiming to streamline the modulation process in contrast to conventional methods. The proposed
simplified modulation technique paves the way for more straightforward and
efficient control of multilevel inverters, enabling their widespread adoption and
integration into modern power electronic systems. Through the amalgamation of
sinusoidal pulse width modulation (SPWM) with a high-frequency square wave
pulse, this controlling technique attains energy equilibrium across the coupling
capacitor. The modulation scheme incorporates a simplified switching pattern
and a decreased count of voltage references, thereby simplifying the control
algorithm.
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.
2. • Describe the different types of Safety valves.
• Describe the parts and operation of a typical
huddling safety valve.
• Describe the method for making safety valve
adjustments.
• Describe ASME code requirements as they
relate to Safety Valves.
• Describe testing procedures for safety valves.
Objectives
3. Safety Valve Setting
• Safety valve or Relief valve capacity shall be
such that they will discharge all the steam
generated by the boiler without allowing the
pressure to rise more than 6% above the
highest pressure at which any valve is set
and in no case more than 6% above the
maximum allowable working pressure.
4. Safety Valve Setting
• One or more safety valves on the boiler proper
shall be set at or below the maximum
allowable working pressure.
• If additional valves are used the highest setting
shall not exceed the maximum allowable
working pressure by more than 3%.
5. Safety Valve Setting
• The complete range of pressure settings of all
the saturated steam safety valves shall not
exceed 10% of the highest pressure to which
any valve is set.
• Pressure setting of Safety Relief Valves on high
temperature water boilers may exceed this
range.
6. • Code
– Each boiler shall have at least 1 safety valve.
– Above 500 square feet, 2 or more safety valves are
required.
7. • Twin Valves:
– Valves will be the same size when attached on a
common (Y Base).
– When separately installed, they may be different
sizes. The smaller valve will have a capacity of 50%
of the larger one.
• Spring Limit:
– Up to 250 PSI 10%
– Above 250 PSI 5%
8. • Safety Valve:
– An automatic pressure-relieving device actuated by
the static pressure upstream of the valve and
characterized by full opening pop action.
– It is used for gas or vapor service.
9. • Relief Valve:
– An automatic pressure-relieving device actuated by
the static pressure upstream of the valve, which
opens further with the increase in pressure over the
opening pressure.
– It is used primarily for liquid service.
– Has no huddling chamber.
– A safety valve may be used as a relief valve.
10. • Safety Relief Valve:
– An automatic pressure actuated relieving device
suitable for use either as a safety valve or relief valve,
depending on application.
– Frequently used on the auxiliary systems such as
heaters, condensate returns boiler feed pump
turbines, evaporators, economizers, compressors,
pumps, etc.
– Safety relief and Relief valve testing frequency can be
as short as 6 months or as long as 2 years.
11.
12. • Lifting:
– The kinetic energy produced in the huddling chamber
causes the safety valve to open.
– The name plate capacity lift (in inches) is a
measurement of the spindle travel or "lift". The spindle
should travel a distance equal to or greater than the
nameplate identified "lift" value.
13. • Lifting
– The initial lift is produced when the steam pressure
under the disc exceeds the spring pressure. To assist
in starting the popping, the small jet of steam that
escapes at low lift is deflected by a small angle on the
nozzle ring. The escaping steam begins to react
against the upper guide (adjusting ring) and push the
disc up to a high lift.
14. • Lifting
– The reaction of the deflected steam pushes against
the under side of the disc and lifts it still higher on an
accumulation of pressure. In this way the valve
reaches a lift equal to or greater than "full bore" lift
within an accumulation of 3 percent above the set
pressure.
– Lifting arm can swivel through a 225 degree arc on
the valve body.
16. • Blowback (Blowdown):
– Determined by escape area between adjusting ring
and nozzle ring.
– Adjustments of over 10 notches on rings requires re-
testing of safety valve.
– The difference between opening and closing
pressures.
17. • Blowback (Blowdown):
– 4% but not less than 2 PSI, except on:
1.Boilers of Once Through or Forced Circulation with no fixed
water level; Blowback will be 10%.
2.Safety valves open and remain open below set pressure
18. • Adjusting Ring:
– Moving towards safety valve seat (Left) increases
blowback.
– Used for major adjustments, controls the amount of
blowdown/blowback.
– DO NOT move more than 10 notches without
retesting. Always record number of notches valve
was adjusted.
19. • Nozzle Ring:
– Moving towards safety valve seat (( Right) increases
blowback.
– Used for minor adjustments, such as when warn (also
called simmer) must be eliminated.
–
– DO NOT move more than 1 notch without
retesting. Always record number of notches valve
was adjusted.
– On high-pressure valves the nozzle ring can be very
effective in reducing the blow down
20. • Discharge Line:
– At least 1 pipe size larger than valve outlet.
– Direct as possible to atmosphere.
– Adequately supported for expansion.
– Open blow drain at base.
21. • Valve Drain:
– Adequate drain below seat level.
• Full Bore Opening:
– Maximum effective lift will be equal to diameter of disk
divided by 4. ( D / 4).
– Full Bore" is that point where the area of the nozzle,
rather than the lift, limits the discharge capacity of the
valve.
23. • Blowback Adjustment
– Major Adjustments, Adjusting Ring.
– Fine Tuning, Nozzle Ring.
– If you are adjusting the ring and you move it 10
notches to get proper adjustment, then the safety
valve requires an overhaul.
– Both rings have right-handed threads.
24. • Blowback Adjustment
– Moving rings to the right (or anti-clockwise)
RAISES rings.
– Moving rings to the left (or clockwise) LOWERS
rings.
– To increase blowback move rings CLOSER
together.
– To decrease blowback move rings APART from
each other.
– Gag safety valve while adjusting.
25. • Opening Pressure or Popping Pressure
– When the popping pressure is changed, a slight
adjustment of the blow down may be required.
– Raising the popping pressure lengthens the blow
down, lowering the popping pressure shortens it.
– A change of less than 5 pounds usually does not
call for any adjustment
26. • Over-pressure Situation
– When the safety valve fails to open, reduce
pressure, try lifting by hand, then raise
pressure to popping point.
– If the safety valve will not open, DO NOT try
to lift the valve manually while at popping
pressure. Take the boiler down and overhaul
the valve.
27. • Over-pressure Situation
– If the valve does not operate at its set
pressure and does not respond to
readjustment, do not attempt to free it by
striking the body or other parts of the valve.
That valve should be repaired while the boiler
is out of service.
– Do not attempt to stop valve leakage by
compressing the spring or using excessive
gagging force.
28. • Safety Valve Failures:
– The most common cause of safety valve
failing to open at the set pressure is the
accumulation of corrosion deposits between
the valve disk and seat.
– This usually happens when the safety valve
"weeps" or leaks slightly
29. • Manual Operation:
– At 75% of boiler pressure a safety valve can
be manually lifted.
• Material:
– The disc and seat are made of a non-
corrosive material.
– Carbon steel will not be used because carbon
makes the steel corrode.
30. • Discs:
– Seat and discs may be either flat or 45o.
– Seat can be inclined at any angle between
45o and 90o inclusive, to the centerline of the
spindle.
31. • Saturated Valves:
– Highest set valves 3% above maximum
allowable pressure.
– Range 10% from lowest to highest set valve.
– If one valve is set at or below maximum
allowable pressure then under no condition
will pressure exceed maximum allowable
pressure by more than 6%.
32. • Superheater Valves:
– Integral superheater safety valve is set
approximately 5% below lowest saturated
valve.
– Capacity of superheater safety valves equals
25% of total capacity of boiler.
• Reheater Safety Valves:
– They are NOT INCLUDED in the relieving
capacity of the boiler
33. • Enclosed Spring Safety Valves:
– The maximum temperature limit is 450oF.
– A cooling spool is used to dissipate heat from
the spring.
34. • Relieving Capacity:
– Can be determined by three different
methods.
– Accumulation Test.
– By calculation using the evaporative capacity
of a boiler.
– And by the fuel burning capacity of a boiler.
35. • The minimum required relieving capacity
of the safety valves or safety relief valves
shall not be less than the maximum
designed steaming capacity as determined
by the manufacture.
• An economizer, which may be shut off
from the boiler to become a fired pressure
vessel, shall have one or more safety
valves.
36. • Accumulation Test:
– Can not be done with an attached
superheater or reheater.
– If superheater is separately fired and a stop
valve is located between the boiler drum and
superheater then the accumulation test can
be done.
37. • Accumulation Test:
– An accumulation test is done with all steam
outlets closed and fires at maximum. When all
safety valves have lifted, the pressure will not
exceed maximum allowable by more the 6%.
– Use a test gage when doing accumulation
test.
– Over 6% you need more safety valves or
increased relieving capacity of existing safety
valves.
38. • Water Level:
– When testing safety valves with steam, the
drum level should be normal.
– Feed only sufficient water to maintain the
level.
– The temperature in the drum can also effect
the valve operation.
39. • Police Pop Valve:
– It is used in heating systems.
– It is a pressure-relieving valve.
40. • Foaming, Priming, Carry over, Oil:
– When condition has been rectified, lift the
safety valve by hand.
• Hydrostatic Test:
– Remove safety valves and blank off flanged
connections rather than installing gags.
41. • Gags:
– Finger Tight only.
– Adjusted at 80% of hydrostatic test pressure.
42. ASME Code Excerpts regarding Safety Valves
Code 67-1: Each boiler shall have at least one safety valve or safety relief valve. If it has more
than 500 square feet of bare tube water heating surface, it shall have at least two valves.
For a boiler with a combined bare tube and extended water heating surface exceeding 500
square feet, two or more valve are required only if the designed steam generated capacity
of the boiler exceeds 4,000 lbs./hr.
Safety Valve: An automatic pressure-relieving device actuated by static pressure up stream of
the valve and characterized by full bore pop action. It is used for compressive fluid service
(gases).
Safety Relief Valve: An automatic pressure actuated relieving device suitable for use either as a
safety valve or a relief valve depending on application.
Relief Valve: An automatic pressure-relieving device actuated by static pressure upstream of
the valve and keeps opening further as pressure increases (no pop action). It is used
primarily for non-compressible fluid service (liquids).
Code 67-2: The safety valve capacity for each boiler shall be such that the safety valve or
valves will discharge all the steam that can be generated by the boiler without allowing the
pressure to rise more than 6% above the highest pressure at which any valve is set and in
no case more than 6% above the maximum allowable pressure.
Code 67-2.1 : The minimum required relieving capacity of the safety valves on any boiler shall
not be less than the maximum steaming capacity determined by the manufacturer.
43. Code 67-3: One or more safety valves on the boiler proper will be set at or below the maximum
allowable pressure. If additional valves are used, the highest set pressure shall not exceed
maximum allowable pressure by more than 3%. The range of all safety valves on the boiler shall
not exceed 10% of the highest pressure to which any valve is set.
Code 67-4: On a universal boiler with no fixed water level equipped with automatic controls and
protective interlocks responsive to steam pressure, safety valves may be provided as above, or
the following overpressure protection shall be provided.
One or more power actuated pressure relief shall be provided in direct communication with the boiler
when the boiler is under pressure and shall receive a control signal to open when the maximum
allowable pressure at the superheater outlet is exceeded.
The combined relieving capacity of all such valves shall not be less than 10% of the maximum
designed steaming capacity under any load condition.
Code 67-:4.1 An O.S.&Y isolating valve may be installed between the relief valve and the pressure
source to allow maintenance.
Power actuated pressure relief valves discharging to intermediate pressure stages or incorporated into
bypass and/or startup circuits need not be capacity certified.
Code 67-4.1: Power actuated pressure relief valves that discharge directly to the atmosphere will be
capacity certified.
Spring loaded safety valves shall be provided having a combined total relieving capacity, including that
of the power actuated pressure relieving capacity of not less than 100% of the designed steaming
capacity of the boiler. In this total, no credit in excess of 30% of the total required relieving
capacity shall be allowed for the power actuated pressure-relieving valves.
Code 67-4.2: The set pressure of the safety valves shall be such, that when they (together with the
power actuated relief valves) are in operation the pressure will not rise more than 20% above the
maximum allowable pressure of any part of the boiler.
All safety valves shall be so constructed that the failure of any part cannot obstruct the free and full
discharge of steam from the valve. Safety valves shall be direct spring loaded with seats inclined
at any angle between 45 degree and 90 degree inclusive to the centerline of the spindle.
44. Code 67-5: Deadweight or weighted lever type safety valves shall not be used.
Code 67-7: Safety valve may have bronze parts provided temperature and pressure limitations are not
exceeded. They shall not be used on superheaters delivering steam at a temperature above
450°F and 306°F respectively.
Every attached superheater shall have one or more safety valves located between the superheat
outlet and the first stop valve. The exact location of each valve shall be such that uniform steam
flow through the superheater is maintained regardless.
Code 68-1: The pressure upstream of each valve shall be considered in the determination of set
pressure and relieving capacity.
Code 68-2: When there are no intervening valves between the boiler and the superheater, the
discharge capacity of the superheat safety valves will be included in the total relieving capacity of
the boiler provided the discharge capacity of the boiler safety valves is at least 75% of the total
required.
Code 67-4: Every reheater will be protected from overpressure by one or more safety valves but they
are not included in the required relieving capacity for the boiler and superheater.
Code 68-5: A soot blower connection may be attached to the same outlet from the superheater or
reheater that is used for the safety valve connection.
Every safety valve discharging superheated steam above 450 degrees F shall have a casing, including
the body, base, spindle, and bonnet of steel, steel alloy or equivalent heat resisting material. The
seat and disk shall be of heat erosive and corrosive material.
Code 68-6: The spring fully exposed will be protected from direct contact with escaping steam by a
cooling spool and deflector.
Capacity certificate tests shall be conducted at a pressure, which does not exceed the set pressure by
3% or 2 psi, whichever is greatest.
Safety valves will be adjusted so that the blowdown does not exceed 4% of the set pressure for valves
set below 100 psi, the blowdown shall not exceed 4 psi.
45. Code 69-1.4: On universal boilers with no fixed water level, safety valve blowdown will not exceed
10% of the set pressure.
Code P 67-1: When two safety valves are independently installed on a boiler, the smaller valve will
have a relieving capacity not less than 50% of the larger valve. Multiple valves installed on a
common "Y" base or common body will be of equal size and capacity.
Safety valves shall be installed independent of any other connection and as close as possible to the
boiler or pressure source, without any unnecessary intervening pipe or fitting. Any such
intervening fitting cannot be longer than the face-to-face dimension of the original fitting.
Every safety valve will be installed so that the spindle is vertical.
The opening or connection between the boiler and the safety valve shall be equal to at least the area
of the valve inlet.
No valve of any description shall be placed between the boiler and the safety valve or, the safety valve
and the atmosphere. The cross sectional area of the waste pipe shall be not less than the area of
the valve outlet or of the total of the areas of the valves discharging thereto.
It shall be as straight and direct as possible to the atmosphere and properly supported to avoid undue
stress on the valve or valves.
Provision for gravity drain shall be made in the waste pipe at or near each valve.
If a muffler is used on a safety valve, it shall have sufficient outlet area to prevent backpressure
interfering with the proper operation of the valve. The muffler plate will be arranged so as to
prevent restriction of steam flow due to deposits.
46. Code 71-4: Safety valves exposed to outdoor elements that could affect operation may be shielded by
a cover properly installed to permit servicing and normal operation.
Safety valves are designed and constructed to operate without chattering and attain full bore opening
at a pressure no greater than 3% above their set pressure. After blowing down all valves will close
at a pressure not less than 96% of the set pressure of the lowest set drum value.
The minimum blowdown shall be 2% of the set pressure except when the maximum allowable
pressure is less than 100 psi, in which case blowdown will be between 2 and 4 psi.
Code 72-1: Safety valves for universal boilers with no fixed water level shall be adjusted for a
blowdown not more than 10% of the set pressure and marked accordingly.
Code 72-3: The spring in a safety valve shall not be reset for any pressure more than 5% above or
below that for which the valve is marked.
Popping point tolerance plus or minus shall not exceed:
Pressure Tolerance Range
Up to 70 psi 2 psi
70 to 300 psi 3%
300 to 1,000 psi 100 psi
Above 1,000 psi 1%
To verify that a safety valve is free to lift, a substantial lifting device shall be installed which allows
manual lifting of the valve when boiler pressure reaches 75% of the set pressure
47. Code 73-1.3: The lifting device shall be such that it cannot hold the disk in the lifted position when the
external force is removed.
Means shall be provided so that all external adjustments can be properly sealed by the manufacturer
or his authorized agent or assembler.
Code 73-1.4: The seat of a safety valve shall be attached to the body of the valve so that there is no
possibility of the seat rising.
A body drain below seat level shall be minimum 3/8" n.p.s. when the valve exceeds 2 1/2" n.p.s. below
2 1/2" n.p.s. The drain shall be minimum 1/4" diameter.
Code 73-2.1: Cast iron seats and disks are not allowed.
Code 73-2.2: Adjacent sliding surfaces such as guides and disks or guide holders shall be corrosion
resistant material.
Safety valves must be gagged or have hydrostatic test plugs installed prior to hydrostatically testing
the boiler.
Test plugs are recommended especially for pressures above 2,000 psi where misapplication of gags
could result in safety valve seat or spindle damage.
Code 2.272: Gags will not be fully tightened until hydrostatic pressure is 80% of operating pressure.
Code 4.110: Inspection and testing of safety valves should be performed on an annual cycle.
48. GENERAL INFORMATION
• Kinetic energy produced in the huddling chamber causes the valve to pop open.
• Popping pressure is determined by the tension of the spring.
• A safety valve pops to full bore opening which is equal to one quarter of the disk diameter.
(Diameter / 4)
Blowback is determined by altering the distance between the adjusting and nozzle rings.
1. Moving them closer increases blowback moving them apart decreases blow back.
2. The rings are attached by a right hand thread.
3. Move them to the right or anti/clock raises them.
4. Move them to the left or clock lowers them.
5. Major adjustments are made with the adjusting ring; fine tuning with the nozzle ring.
6. If adjustment requires ten notches, valve needs to be overhauled.
• Manual operation of safety to relieve pressure in case of low water is not allowed.
• Waste pipe supports should be examined semiannually.
• Independent economizers (steaming) superheaters and reheaters will be protected by safety
valves but will not be included in the relieving capacity of the boiler.
Safety valve capacity can be formulated by one of three ways:
1. Accumulation test.
2. Measuring the max fuel burn, and computing the evaporating capacity on basis of calorific
value
3. Determining the evaporative capacity on the basis of feedwater flow.
49. • The sum of the relieving capacities of all valves shall be equal or greater than the maximum
evaporative capacity of the boiler.
• Safety valves tests are mandatory at time of boiler inspection. This may be done prior to removing
from service by pinching down on non-return valve until lowest set valve lifts, then open non-return
valve, gag the lowest set valve, then do same for each valve.
• When live testing safety valves, the drum level should be lower than normal, but in safe level.
Safety Valve - Stamping: Each safety valve shall be plainly marked as follows:
1. Manufacturer's identifying mark
2. Manufacturer's design or type number
3. Size..... Seat Diameter....
4. PSI...... (Lifting)
5. Blowdown........
6. Capacity....... lbs/hr
7. Capacity lift.....(Distance valve lifts when blowing at accumulation)
8. Year built
9. ASME symbol
50. • When safety valve fails to open, reduce pressure; try lifting by hand, then raise pressure to
popping point. If it still does not operate, replace it.
• Leaking safety valves should not be gagged. Lift by hand, if it still leaks, replace it.
• Hand lifting safety valves to relieve pressure in a low water situation is not allowed.
• Blow safety valves good after a foaming priming carryover or oil in water situation has been
rectified.
• Bellows type safety valve used in industrial systems where vapor may be corrosive - bellows
protects valve spring and other components.
• Safety relief valves used on heating systems opens slowly at set point. If pressure still increase,
then it will pop.
• Pressure and temperature relief valve used on hot water systems, spring loaded valve and fusible
element.
Testing Intervals:
For Detroit Edison the fossil-fired utility boiler safety valves are to be tested at a regular frequency
determined by their maintenance history. All safety valves shall be tested within the span of two
periodic outages or a maximum of four years.
Power Plant Order #8 – Boiler Safety Valve Testing
http://fossilgen.deco.com/dtepowgen/ppo/ppo.htm