indicator/stopper

：This article brief disscuss the primary structure and working principle of the valve position indicator in the immersion type hydraulic driving butterfly valve，and introduced the correct adjustive method of the valve position indicator.

简要叙述了浸液式液压驱动蝶阀阀位指示器的主要结构及工作原理，并介绍了阀位指示器正确调节方法。