Relief Valve (RV): automatic system that relief by static pressure on a liquid. It specifically opens proportionally with pressure increasing.h thng t ng gim p lc tnh trn mt cht lng. N c bit m ra tng ng vi p lc ngy cng tngSafety Valve (SV): automatic system that relief by static pressure on a gas. It specifically opens almost straight to full lift after a pop sound.h thng t ng gim p lc tnh trn mt kh. N c bit m ra gn nh thng y thang my sau khi mt m thanh pop.Relief valve always position in the suction line in order to relief the extra pressure, while safety valve is always placed at discharge line to release excess pressure. Van x lun v tr cc ng ng ht gim p lc thm, trong khi van an ton lun c t dng x gii phng p lc d tha.

I would take that one step further by stating that a RELIEF VALVE" is one that is "meant" to be lifted off its seat, as opposed to a "SAFETY RELIEF VALVE" which is not!

Ti s c thm mt bc na bng cch ni rng mt "RELIEF VALVE" l mt trong l "c ngha l" c nng ln khi ch ngi ca mnh, nh tri ngc vi mt "AN TON MIN VAN" m khng phi l!Safety valves are always mounted on vessels to protect them against pressure build up (even if discharge valves are closed accidently) whereas relief valves are installed on pipe lines to relieve excess pressure and are normally installed across pumps. A good example can be seen in pressure cookers, the center valve is a relief valve whereas it has a safety valve in case relief valve fails.Van an ton lun c t trn tu bo v h khi p lc xy dng (ngay c khi van x ng li v tnh) trong khi van gim c ci t trn cc ng ng gim bt p lc qu mc v thng c ci t trn my bm. Mt v d c th c nhn thy trong ni p sut, van trung tm l mt van x trong khi n c mt van an ton trong trng hp van x hng.What is the difference between a safety valve and a relief valve?

A safety relief valve, or pop-off valve, is set to pre-determined pressure using a spring force to counteract the air pressure force. When the force created from the air pressure becomes greater than the spring force, the valve 'pops' fully open and vents air to the atmosphere. Safety relief valves are sized in such a manner that the valve will always have a greater flow capacity than the source creating the air pressure (i.e. an air compressor). The valve will remain open until a reseat pressure is reached. This reseat pressure varies with valve type and is usually in the range of 35% to 75% of the set pressure. Mt van an ton, van hay pop-off, c thit lp xc nh trc p lc bng cch s dng mt lc l xo chng li cc lc p sut khng kh. Khi lc to ra t cc p lc khng kh tr nn ln hn lc l xo, van 'bt' hon ton m v l thng hi khng kh vo kh quyn. Van gim an ton c kch c mt cch nh vy m van s lun lun c mt sut lu lng ln hn cc ngun to ra nhng p lc khng kh (tc l mt my nn kh). Van s vn m cho n khi mt p lc reseat l t. p lc reseat ny thay i theo loi van v thng l trong khong t 35% n 75% ca p sut t A relief valve is set to a pre-determined pressure with a spring force counteracting the force created by the pressure from the air. When the force created from the pressure of the air becomes greater than the force of the spring, the valve will start to open and flow to atmosphere. As the pressure continues to increase, the valve will open further, allowing more flow. As the pressure decreases, the valve will close near the pressure at which it opened. Mt van x c t thnh mt p lc c xc nh trc vi mt lc l xo chng li cc lc to ra bi p lc t khng kh. Khi lc to ra t p lc ca khng kh tr nn ln hn lc ca l xo, van s bt u m v chy ra khng kh. Khi p sut tip tc tng, van s m tip, cho php lu nhiu hn. Khi p sut gim, van s ng ca gn cc p lc m n m ra.The ASME / ANSI PTC25.3 standards applicable to the USA define the following generic terms:

Pressure relief valve - A spring-loaded pressure relief valve which is designed to open to relieve excess pressure and to reclose and prevent the further flow of fluid after normal conditions have been restored. It is characterized by a rapid-opening 'pop' action or by opening in a manner generally proportional to the increase in pressure over the opening pressure. It may be used for either compressible or incompressible fluids, depending on design, adjustment, or application.

This is a general term, which includes safety valves, relief valves and safety relief valves.

Safety valve - A pressure relief valve actuated by inlet static pressure and characterized by rapid opening or pop action.

Safety valves are primarily used with compressible gases and in particular for steam and air services. However, they can also be used for process type applications where they may be needed to protect the plant or to prevent spoilage of the product being processed.

Relief valve - A pressure relief device actuated by inlet static pressure having a gradual lift generally proportional to the increase in pressure over opening pressure.

Relief valves are commonly used in liquid systems, especially for lower capacities and thermal expansion duty. They can also be used on pumped systems as pressure overspill devices.

Safety relief valve - A pressure relief valve characterized by rapid opening or pop action, or by opening in proportion to the increase in pressure over the opening pressure, depending on the application, and which may be used either for liquid or compressible fluid.

van x p sut - Mt van gim p lc l xo c thit k m gim p lc qu mc v reclose v ngn chn dng chy ca cht lng hn na sau khi iu kin bnh thng c khi phc. N c c trng bi mt nhanh chng m 'pop' hnh ng hoc bng cch m mt cch thng t l thun vi s gia tng p lc ln p lc m ca. N c th c s dng cho cc cht lng hoc nn hoc khng nn c, ty thuc vo thit k, iu chnh, hoc ng dng.

y l mt thut ng chung, trong bao gm cc van an ton, van v van cu tr an ton. Van an ton - Van gim p kch thch bi nhng p lc ht tnh v c trng bi vic m nhanh chng hnh ng hoc pop.Van an ton c s dng ch yu vi cc loi kh nn v c bit cho cc dch v xng hi v khng kh. Tuy nhin, h cng c th c s dng cho loi qu trnh ng dng m h c th cn thit bo v cy trng hoc ngn chn s h hng ca sn phm c x l.

Van Relief - Mt thit b gim p lc kch thch bi nhng u vo p sut tnh c mt thang my dn dn thng t l thun vi s gia tng p lc hn p lc m ca.

Van gim thng c s dng trong cc h thng cht lng, c bit l i vi kh nng thp hn v nhim v m rng nhit. H cng c th c s dng trn cc h thng bm nh cc thit b overspill p.

Van an ton - Van gim p c trng bng cch m nhanh chng hnh ng hoc pop, hoc bng cch m tng ng vi s gia tng p lc ln p lc m ca, ty thuc vo ng dng, v c th c s dng hoc cho dch lng hoc nn.