First, the properties and uses of the product: the maintenance of the valve inlet pressure is nearly constant, excess fluid in the system through the pressure control valve reflux valve. 1, there are three pressure regulator Type: the hex adjustment bolts with protective cover, adjustable handle, lockable adjustment handle. Second, product technical parameters: DB-type relief valve by the pilot valve and the main valve for pressure control system, pilot control two concentric relief valve, pilot valve and main are cone structure. There are two general structure: relief valve, direct-acting relief valve. 2, pilot-operated relief valve relief valve: pressure range regulator deviation pressure runout small, quick action, overload, low noise.