Valve material depending on the operating conditions in accordance with GOST 15150-69 (U, HL, UHL1). These information is given in the product data sheet.
3. The device is shown in the drawings. Valve closing-opening is made by the force resulting from the supply or return of the fluid under pressure into the clapper chamber. Valve closes when the pressure drops due to the weight of the clapper and the back pressure of the working fluid.
Valves are manufactured on individual sizes, parts of one valve are not interchangeable with parts of other valve.