■ Pilot Operated Relief Valves These valves protect the hydraulic system from excessive pressure, and can be used to maintain constant pressure in a hydraulic system. Remote control and unloading are permitted by using vent circuits. Pilot Operated Relief Valves ■ Specifications Model Numbers Note: Refer to the Minimum adjustment Pressure characteristics on page 214. ■ Model Number Designation ★ Use high venting pressure type to reduce the response time from unload to onload. Pilot Operated Relief Valves

• Mounting Bolts • Sub-plates are available. Specify the sub-plate model number from the table above. When sub-plates are not used, the mounting surface should have a good machined finish. ■ Instructions • If a remote control relief valve is used in the vent circuit, see page 203. In addition, if the internal volume of the vent line is too large, chattering is likely to occur. Thus, as far as possible reduce the inside diametre and the length of the pipe. • To adjust the pressure, loosen the lock nut and turn the handle slowly clockwise for higher pressures or anti-clockwise for lower pressures....

DIMENSIONS IN MILLIMETRES (INCHES) Pilot Operated Relief Valves ★ There are two threaded connection pressure ports. They can be connected each other in-line; one as inlet and the other as an outlet or the valve can be used by plugging one of the pressure ports. Pilot Operated Relief Valves

DIMENSIONS IN MILLIMETRES (INCHES) Pilot Operated Relief Valves

DIMENSIONS IN MILLIMETRES (INCHES) Pilot Operated Relief Valves Pilot Operated Relief Valves

■ Nominal Override Characteristics BT-03, BG-03 Hydraulic fluid: Viscosity : 35 mm^/s (164 SSU) Specific Gravity: 0.850 BT-06, BG-06 Flow Rate ■ Min. Adj. Pressure & Vent Pressure vs. FlowBT-03, BG-03 BT-10, BG-10 214 Pilot Operated Relief Valves

I Spare Parts List Note: When ordering the seals, please specify the seal kit number from the table below. • List of Seal Kits Pilot Operated Relief Valves Valve Model Numbers Note: No bonded seals are included in the seal kits. Note: When ordering the seals, please specify the seal kit number from the table below. • List of Seal Kits Valve Model Numbers Pilot Operated Relief Valves 215