Red-Valve - Pinch Valve Sleeves -Brochure

Red Valve Company, Inc. • 700 North Bell Avenue, Carnegie, PA 15106 • 412-279-0044 • Fax 412-279-7878 • www.redvalve.comFFoouunnddeedd iinn 11995533 InstallationPinch Valve Technical InformationPinch Valve Technical InformationThis bulletin has been prepared for use during designand purchasing. This bulletin is not intended to replacethe Installation, Operation, and Maintenance Manual,but should be used in conjunction with the IOMManual.During installation you may need to retorque the flangebolts several times for a proper seal. This will overcomeany leaks due to the cold flow of the rubber sleeveflange.Initially, torque the bolts to the recommended values.Stroke the valve open and closed several times, with noline pressure. Then, recheck the bolt torque. Retorquethe bolts to the proper torque. Pressurize the line. Oncepressure is introduced, you may again need to retorquethe bolts. If air or process fluid leaks, increase the rec-ommended torque in increments of 50 ft. lbs.A. Standard pinch valve sleeves are built to schedule40 pipe I.D. and to ANSI Class 125/150# flange andbolt circle specifications. It is recommended thatthe mating flanges are flat and full faced.B. It is recommended that the mating flange be serrat-ed to “grip” the rubber sleeve. The serrations shouldbe cut 1/16” deep, with a 90° angle tool point. Thepitch should be 8 (eight) cuts per inch.C. Mating flange ID must match sleeve ID.D. When installing a pinch valve to a rubber, PVC, orany “slick” mating flange, we recommend that youinstall a metal serrated gasket between the twoflanges to assist in the seal.E. When bolting a pinch valve to a PVC or Syntheticmating flange, use a split back-up retaining ring,since the mating flange will yield prior to generatingenough force on the flange faces for a proper seal.F. Always use a “star” pattern when bolting a pinchvalve.Note: If long, unsupported lengths of steel, plastic, or synthetic pipeare being used, the pipe may yield or sag due to the valve weight.This may cause an inadequate seal between the valve and flanges. Becertain sufficient pipe hangers are used and properly located to sup-port the total weight of the valve and the process fluid.1/16"90D1 = D21234567 8ValveBodyRubber SleevePipeline FlangeWeldneck ispreferredA.B.C.D.E.F.