RELIEF VALVE RELIEF VALVE 3) 3) 2 1 Body 2 Plug 3 O-ring 4 Plunger 5 Piston 6 Spring 7 Spring seat 8 Seat 9 O-ring 10 Nut 3 10 5 9 7 1 6 4 8 (1) (1) Construction of relief valve Construction of relief valve The valve casing contains two cartridge type relief valves that stop the regular and reverse rotations of the hydraulic motor. The relief valves relieve high pressure at start or at stop of swing motion and can control the relief pressure in two steps, high and low, in order to insure smooth operation. (2) (2) Function of relief valve Function of relief valve Figure illustrates how the pressure acting on the relief valve is related to its rising process.
Here is given the function, referring to the figure following page. P P=pressure, T=time P S 4 P 1 3 2 1 T 2-17