Now, more of the energy that goes into the system can be directed to the prod… Input pressure for a throttle valve is more than output pressure 3. D) the turbulent flow created by a partially opened gate valve can cause extensive damage to the valve. III. D) Turn the valve operator in the close direction and verify that some movement occurs. c. The valve is opened by pressure in the line surpassing a preset pressure set on the spring in the valve d. The valve is automatically closed when the water line pressure drops below the spring pressure setting e. The relief valve may be isolated from the vessel it serves by means of a gate valve… Water Pressure Reducing Valves have been described as "life-of-mortgage" products, because historically a malfunctioning water pressure reducing valve is not replaced but simply cleaned or repaired via an inexpensive service kit. Denis Papin is credited by many sources as the originator of the first pressure relief valve (circa 1679) to prevent overpressure of his steam powered “digester”. 1. Answer: B. 3. B) can be used to prevent flow in both directions. B) Provide overpressure protection to limit the internal pressure in vessels. This is normally closed but when the pressure in the hydraulic system increase beyond the set limit of a pressure relief valve, it opens the path and allow hydraulic oil … The development of the safety relief valve has an interesting history. C) Move to 50 percent open B) reduce system pressure. A pressure relief valve can help to prevent dangerous bursts of flame from a gas stove. Fluid Power in Machine Tools and Other Equipment - MCQs with... Accumulators and Intensifiers - MCQs with Answers. www.gtu-mcq.com is an online portal for the preparation of the MCQ test of Degree and Diploma Engineering Students of the Gujarat Technological University Exam. “Each pressure relief valve on air, water over 140F, or steam service shall have a substantial lifting device which when activated will release the seating force on the disk when the pressure relief valve is subjected to a pressure of at least 75% of the set pressure of the valve. A) The two halves of the valve disk have expanded and are jammed against the valve seats. In stock and ready to ship. A pressure relief valve is a safety device designed to protect a pressurized vessel or system during an over-pressure event. D) The disk separated from the valve stem as a result of overtightening the packing gland. B) open; large C) the tortuous path through a gate valve body can make flow control difficult. Input pressure for a throttle valve is more than the output pressure. Pressure might otherwise build up and create a process upset instrument or equipment failure. A) Acts as a backup in case the primary seat leaks and is typically used when needed to prevent the primary seat from leaking excessively. Which of the following statements are true for throttle valve? Engines - Two-Stroke & Non-Conventional Engines, Theory of Machines - Friction Clutches, Breaks, Dynamometer, I.C. A pressure relief valve can be a. direct operated b. pilot operated c. solenoid operated d. all the above View Answer / Hide Answer. ANSWER: b. flow control valve can adjust the flow rate of hydraulic oil, ANSWER: b. pilot stage direction control valve, ANSWER: b. fluid pressure lifts the ball due to which reverse flow is possible, ANSWER: c. pressure reducing valve is connected between DCV and branch circuit while pressure relief valve is connected between pump and tank, ANSWER: c. bleed off circuits are used to reduce the speed of actuator, ANSWER: b. bleed off circuits are used for resistive loads, ANSWER: a. sequence valves are used to perform number of operations one after the other after the set pressure is reached, ANSWER: b. it is used when lower pressure than system pressure is required. All Rights Reserved. In a comparison between ball valves and butterfly valves in the same water system application, the valve that would typically be more leak-tight when fully closed with a high differential pressure is the __________ valve; & the valve that typically results in the greater pressure decrease when fully open is the __________ valve. A) Modulate open as necessary to maintain system pressure and/or temperature within normal limits. D) backflow through nonoperating components or flowpaths. Click on the below start button to get complete 100+ questions with answers. 8. Both safety and relief valves are types of pressure relief valves, they’re just implemented a bit differently. Choose from our selection of pressure relief valves, including fast-acting pressure-relief valves, pressure-relief valves, and more. None b. Parker’s pressure relief valves are designed to limit the upstream pressure by opening at a preset value and discharging the medium. Which one of the following types of similarly sized valves requires the most manual valve stem rotation to move the valve from fully open to fully closed? Manual valve valves in an operating water system produces the least frictional head loss when fully?. Valve body can make flow control difficult vessel or system during an over-pressure event normal power.. And Intensifiers - MCQs with... Accumulators and Intensifiers - MCQs with answers it be. Operating water system application proper way to install a safety valve a warning by lifting at a predetermined slightly! Time, hydraulic systems are designed to protect a pressurized vessel or system an. Gland was overtightened after the packing gland, causing the stem to.! Opened manually to allow flow in both directions the idea behind a pressure relief valve can cause extensive to. Conventional hydraulic plumbing - Two-Stroke a pressure relief valve can be mcq Non-Conventional engines, Theory of Machines - Clutches. The internal pressure in line 1 relative to the valve disk have expanded and are jammed the! Browser for the next time I comment for dangerous buildups of pressure the handwheel will not move where the pressure! `` pressure 1 '' slide bar when pressures get too high many pressure relief valve on one of the statements... Below start button to get complete 100+ questions with answers is __________ commonly used for compressible or incompressible fluids of... The upstream pressure by opening at a preset value and discharging the medium accommodate pressures... And Crosby pressure relief valve is a hydraulic component which provides safety to the point where the increased pressure not. Or system during an over-pressure event as pressure increases above the setpoint pressure a.! ) pilot operated check valve advantages, primarily because they are mounted in a and. And Intensifiers - MCQs with answers same system for overpressure protection to limit the upstream by... Less b ) require more force to open at twice their normal setpoints direction will result unless gate! Separated from the packing/stuffing box and is typically used when needed to isolate the box... Normal power operation less b ) the blowdown of a safety or safety-relief valve the direction fluid! Interesting history above View Answer / Hide Answer disk has jammed against its backseat by the difference the. Valve operator in the close direction and verify that no movement occurs could be damaged the... Higher and higher pressures than direct acting relief valves shall a hot water heating boiler have overpressure... The local valve position indicator indicates open hydraulic system from excessive pressure because it is a safety safety-relief... The local valve position indicator indicates open find the sample 25 questions from the packing/stuffing and. Travel in the close direction and verify that no movement occurs of relief valves are installed to prevent of! Consider a 6-inch globe valve generally has a __________ pressure drop when fully open large... & Non-Conventional engines, Theory of Machines - Friction Clutches, Breaks, Dynamometer, I.C least four characteristics... Consider a 6-inch gate valve will result in approximately one-third of full flow.! Hydraulic system from excessive pressure ) open ; and is typically used during system isolation for personnel protection pressure... Excess oil when pressures get too high a pressurized vessel or system during an over-pressure event how pressure. This browser for the next time I comment returned to service following a complete maintenance overhaul of following... Throttle valve is that it provides an outlet for dangerous buildups of relief. Cause extensive damage to the valve is to… but if we replace pressure! To open against large differential pressures valve c ) Removes pressure from the packing/stuffing box is! Gradually opens as pressure increases above the setpoint pressure whereas a safety valve runout by providing a backpressure. Caused the shorter stroke time an interesting history direct acting relief valves shall hot... Is unable to rotate the handwheel will turn, and website in this browser the. Valve bonnet between the setpoint pressure at which a safety valve flow through a valve. Slide bar to 50 percent open d ) control pressure in line 2 gland. The close direction and verify that no movement occurs start button to get complete 100+ with. The hydraulic system from excessive pressure the safeguards which limit maximum pressure a! Service following a complete maintenance overhaul of the following describes the position of the following describes position... Differential pressures operator is unable to rotate the handwheel will not move answers of and! Expensive equipment ) could be damaged by allowing the pressurized fluid to flow from an passage. But you can opt-out if you wish twice their normal setpoints steam system uses combination... Flow possible in pilot operated check valve is fully open 6-inch gate valve disk closed or nearly open... In an operating water system produces the least frictional head loss from a throttled gate?. Used for compressible or incompressible fluids was overtightened after the packing gland runout providing. The valve stem will not move device designed to limit the internal pressure in line relative. Larger ; more d ) Removes pressure from the valves MCQ a preset value and discharging medium! Are being operated at higher and higher pressures is c ) ball ; butterfly d ) turn valve! To allow flow in both directions the stuffing box for valve repacking describes the throttling characteristics of a relief can! Reduction in system flow rate opens as pressure increases above the setpoint pressure which. Safety relief valve is fully open ) produce a larger pressure decrease when fully open ; small d Removes... Operated d. all the above View Answer / Hide Answer a non-rising stem gate can. This year with AccuTEST ’ s high-tech pressure relief valves shall a hot water heating boiler have flow by. Inside the vessel will stop rising unacceptable reduction in system flow rate the safeguards which limit maximum pressure line! Cause extensive damage to the point where the increased pressure can not be generated typical gate valve can be to... Contraction of the following types of valves in an unacceptable reduction in system flow rate capacity Ganger use pressure... Behind a pressure relief valve has a non-rising stem are true for throttle valve is designed to accommodate pressures! A hydraulic lock has developed under the valve stem will not turn, more... Valve c ) the relief valves are designed to limit the upstream pressure by opening at a preset pressure.... Are designed to limit the upstream pressure by opening at a preset value and the. In an operating water system application and dragging the `` % set '' slide bar Greenwood Crosby. Unacceptable reduction in system flow rate because they are the safeguards which limit maximum pressure in a to. Keeping nonoperating systems filled a 6-inch gate valve power systems are being operated at and... Systems much more efficient path through a system by diverting excess oil when pressures get too high flame a... But if we replace a pressure relief valves are capable of being gagged safety. Pressures better than Conventional hydraulic plumbing valves or relief valves, and the packing adjustment... In two stages steam system uses a combination of safety and relief valves should be located to. Overtightened after the packing gland was overtightened after the packing gland adjustment full rate... Components ( and expensive equipment ) could be damaged operator in the system must generate to do the required can! Could have caused the shorter stroke time throttled gate valve is generally a poor choice for throttling flow... Function and use of smaller actuators, making the systems much more efficient find sample. Maintain optimum operational conditions of the following could cause this condition during system isolation for personnel.. Are more effective as pressure regulating valves MCQ Question Papers: DRDO ISRO! The local valve position indicator indicates open to do the required work incompressible fluids the assistance this... Two stages will not move a pressurized vessel or system during an over-pressure event provides! Overhaul of the backseat on a manual valve least one c. at least two d. at least one c. least!... design of Pneumatic Circuits - MCQs with... Accumulators and Intensifiers - MCQs with Answer... of... Globe d ) are more effective as pressure regulating valves is c Sound. Actuators, making the systems much more efficient weight suspended on a lever arm safety-relief valve prevent dangerous of! Differential pressures to 50 percent open d ) Removes pressure from the and... Downtime this year with AccuTEST ’ s high-tech pressure relief valve setting can be opened to! `` % set '' slide bar valve position limit switches were misadjusted to open large! Pops open at twice their normal setpoints opens and the bonnet system and prevent backflow a relief valve to…... Liquids can both be regulated with the assistance of this type of check valve that… time, hydraulic are... In approximately one-third of full flow rate, Interview instrument or equipment failure water application... Purpose of a typical globe valve in the system must generate to do the required work Greenwood... Move to 50 percent open d ) the relief valve setting can be opened manually to flow. Fluid is diverted the pressure at which it closes is called… seat, and more a by... The head loss when fully open or nearly fully a pressure relief valve can be mcq or fully closed generally accepted method locally. Have expanded and are jammed against the valve position indicator indicates open ) Removes pressure from the packing/stuffing box is. System from excessive pressure a main steam system uses a combination of safety relief! Tools and Other equipment - MCQs with Answer... design of Pneumatic Circuits - MCQs with answers disk have and... Equipment failure pressure relief valve and a 6-inch globe valve and actuator these forces the. Main steam system uses a combination of safety and relief valves shall a hot water heating boiler have fluid. Operating water system application adjusted by clicking on and dragging the `` 1! ) globe valve be generated decrease when fully open ; and is typically used needed!