check valves (Backflow Prevention) a) Swing-type check offer the least pressure drop and offer simple automatic closure; when fluid flow stops, gravity and flow reversal closes valve. Many bronze valves offer a Y-pattern body with an angle seat for improved performance. Resilient seating preferred for tighter shutoff. b) Lift checks come in in-line or globe-style…
a) ball valves Positive Features – Recommendations 1) Bubble-tight shut-off from resilient (TFE) seats 2) Quick 90° open/close, not torque-dependent for seating 3) Straight-through unobstructed flow, bidirectional 4) Minimal pressure drop if full-port selected 5) Can be throttled (Application dependent) 6) Easier to automate than multi-turn valves 7) More compact than multi-turn valves 8) Offers…
a) gate valves Positive Features – Recommendations 1) Good choice for on-off service 2) Full flow-low pressure drop 3) Bidirectional Disadvantages 1) Not for throttling; use fully opened or fully closed 2) Metal-to-metal seating means not best choice for frequent operation. Bubble-tight seating should not be expected with metal-to-metal design. 3) Difficult to automate. Wedge…