导压比3:1 , 节流, LoadAdaptive™ 平衡 阀

Counterbalance valves with pilot assist are meant to control an overrunning load. The check valve allows free flow from the directional valve (port 2) to the load (port 1) while a direct-acting, pilot-assisted relief valve controls flow from port 1 to port 2. Pilot assist at port 3 lowers the effective setting of the relief valve at a rate determined by the pilot ratio. The LoadAdaptive™ counterbalance valve has a higher pilot ratio when the load-induced pressure is less than the setting of the valve (is not moving yet) and when the moving load is a positive load (not overrunning). See P1-P3 diagrams under "Performance Curves." The P1 (Y axis) vs P3 (X axis) curves show the effective setting P1 of the valve for different flows depending on pilot pressure P3. Click Here for LoadAdaptive Technical Tip

Other names for this valve include motion control valve and over-center valve.

• 平衡阀的设定值应该至少为负载压力值的1.3倍。
• 顺时针旋转调节将会减少设定，降低压力。
• Full clockwise setting is less than 500 psi (35 bar).
• Backpressure at port 2 adds to the effective relief setting at a ratio of 1 plus the pilot ratio times the backpressure. NOTE: The ratio depends on the pilot pressure. With no pilot pressure, the backpressure is additive with a factor of 10.
• This valve does not have positive seals on the pilot section and will pass up to 4 in³/min.@1000 psi (65 ml/min.@70 bar ) between port 2 and port 3. This is a consideration in master-slave circuits and in the leak testing of valve-cylinder assemblies.
• Sun的平衡阀可以被安装进执行器内部的安装孔，成为执行器的一部分，进而更加安全地保护回路。
• 有两种单向阀开启压力可选。在防止执行器气穴现象的时候，推荐使用4psi（0.3bar）的单向开启压力。
• 所有的3口平衡阀，负载控制阀，以及先导开启单向阀都结构上可以相互替换。（对同样的规格情况下，他们是相同流量路径相同孔型）
• 标准设定下，阀的复位压力值高于阀开启值的85%。当设定值小于标准设定值，复位压力值的百分比将相应变小。
• Sun浮动式的结构可以最大限度地减少由于过大的安装扭矩以及孔型加工的误差所造成的干涉现象。