The Lee Company Presents

LEE TRI FLOW NOMOGRAM
FOR SKYDROL 500 OR MIL-H-5606 AT 100蚌

Datasheets

187 and 281 PRI

The 187 and 281 Pressure Relief Valves are specifically designed to be the smallest valves available for safety relief applications. Both are constructed entirely of stainless steel and are available screened and unscreened for design flexibility. Built-in damping assures quiet operation.

�.187" PRI - Unscreened

�.187" PRI - Screened

� .281" PRI - Unscreened

� .281" PRI - Screened

375 and 500 Momentum PRI

The 375 and 500 Pressure Relief Valves use the patented 'momentum free' design concept. The unique design compensates for momentum forces that upset the normal force balance of a direct acting valve. These forces are produced by local pressure gradients caused by changes in liquid velocity. (See 'Momentum Forces'). The result is a valve that is both linear and stable throughout the operating range and has low hysteresis, yet is still miniature. The 375 PRI has full open flow capacity of 100 Lohms and the 500 PRI has a 50 Lohm capacity. Both are available in standard cracking pressures from 50 to 500 psid.

� .375" Momentum PRI

� .500" Momentum PRI

281 and 375 High Pressure PRI

The 281 and 375 High Pressure Relief Valves are designed for pressure relief service where operating pressures and pressure spikes are too severe for conventional safety relief valves. These conditions, when encountered by conventional valves can lead to instability, erosion and other damaging phenomenon.

� .281" High Pressure PRI

� .375" High Pressure PRI

Thermal Relief Valve

The Lee TRI has been designed to relieve fluid pressure caused by thermal expansion. When a sealed container is completely filled with fluid, thermal expansion can cause container rupture or seal failure. The Lee TRI eliminates this hazard.

� .187" TRI

� .250" High Pressure TRI

VALVE TYPE	TYPICAL APPLICATIONS	PRES. BAND* %	LOHMS AT MIN. VALVE LIFT**	SUITABLE FOR METERING PARTLY OPEN	SUITABLE FOR THERMAL PRESSURE RELIEF
187 PRI	1) General L.P. relief 2) Pressurizing valve 3) As a check valve	40	1500	Yes	No
281 PRI	1) Safety "pop-off" relief 2) Cross port load alleviation	40	1500	No	No
375 Momentum PRI	1) Filter by-pass relief 2) Lubrication systems 3) Fuel systems	35	500	Yes	No
500 Momentum PRI	1) Filter by-pass relief 2) Lubrication systems 3) Fuel systems	35	350	Yes	No
281 High Pressure PRI	1) Combination thermal pressure relief and low flow relief 2) General low-flow relief	25	Not Limited	No	Yes
187 TRI	1) Thermal pressure relief only	25	Not Limited	Yes	Yes
375 High Pressure PRI	1) General High Pressure relief 2) Cross port load alleviation	28	1500	Yes	No
250 High Pressure TRI	1) High Pressure thermal relief only	25	Not Limited	Yes	Yes