Abstract: A relief valve assembly includes an actuating assembly, a relief valve, and a check valve. The actuating assembly includes a housing forming a cylinder, and a pilot piston within the cylinder. The relief valve includes a housing forming opposed first and second blind bores, a relief valve piston within the first bore and carrying a relief valve member, and a first spring acting between the pilot piston and the relief valve piston to bias the relief valve member toward a valve seat to close the valve seat. A pilot pressure is selectively applied to move the pilot piston toward the first spring to selectively increase the relief pressure of the relief valve from a first relief pressure to a second relief pressure. The check valve includes a check valve member within the second blind bore, a second spring biasing the check valve member away the second blind bore.

Abstract: A relief valve assembly includes an actuating assembly, a relief valve, and a check valve. The actuating assembly includes a housing forming a cylinder, and a pilot piston within the cylinder. The relief valve includes a housing forming opposed first and second blind bores, a relief valve piston within the first bore and carrying a relief valve member, and a first spring acting between the pilot piston and the relief valve piston to bias the relief valve member toward a valve seat to close the valve seat. A pilot pressure is selectively applied to move the pilot piston toward the first spring to selectively increase the relief pressure of the relief valve from a first relief pressure to a second relief pressure. The check valve includes a check valve member within the second blind bore, a second spring biasing the check valve member away the second blind bore.