The valve's closure membermechanism of the valve,involves plugs arethat connectedconnect to thea stem, which is slidadjusted either by sliding or screwedscrewing it up or down to throttle theregulate flow. Plugs arecome typicallyin of the balancebalanced or unbalanced typetypes. Unbalanced plugs, aretypically solid and, are usedsuitable withfor smaller valves or those with low pressure drops. acrossThey theoffer valve.advantages Thesuch advantages areas simpler design, with onepotential possibleleakage leak pathonly at the seat, and usually lower cost. TheHowever, disadvantagesthey are the limited in size;, withas a largelarger unbalanced plugplugs themay require impractical forces needed to seatseal and hold thecontrol flow. oftenOn becomesthe impractical.other Balancedhand, balanced plugs havefeature holes through the plug itself. AdvantagesThey includeoffer easieradvantages shut offsuch as theeasier plug does notshut-off havedue to overcomereduced static forces required. However, they introduce a second potential leak path is created between the plug and the cage, and costthey istend to be generallymore higherexpensive.
