针阀副密封性试验台我厂采用“气动膜片逻辑元件”,实现自动装卡工件,并使气缸活塞往复运动自动化。这种元件寿命可达二千万次,结构简单,成本低,对气液净化要求不高。该试验台工作稳定可靠,操作简便,密封时间准确,可保证针阀间隙在0.002～0.004毫米之间,为提高针阀副密封质量创造了条件。(北京长辛店二七机车车辆工厂) Needle valve Vice sealing test bench I plant the “pneumatic diaphragm logic components” to achieve automatic loading of the workpiece, and reciprocating cylinder piston automation. The life of such components up to 20 million times, the structure is simple, low cost, less demanding on the gas-liquid purification. The test bench work stable and reliable, easy to operate, the sealing time is accurate, can ensure that the needle valve clearance between 0.002 ~ 0.004 mm, to improve the quality of vice seal valve to create the conditions. (Changxin Beijing February 27 locomotive vehicle factory)