Shanghai Lianggong valve teaches you to solve the impact of scale on the valve. Whether it is solenoid valve or electric valve, scale is one of their hazard factors, which will not only cause valve leakage, but even affect the normal operation of the valve in serious cases. Therefore, how to eliminate the impact of scale is a common concern of technicians in valve repair factory.

控制阀的工艺涉及的范围实在太广,不过由于设计执行机构和使用填充材料不同造成控制阀性能差还是可以总结出其规律的:

The process of the control valve involves too wide a range. However, due to the poor performance of the control valve caused by the different design of the actuator and the use of filling materials, its law can be summarized:

1、工艺过程里死区的存在会使过程变量偏离原设定点。所以控制器的输出加大到足于克服死区,只有这一纠正性的动作才会发生。

1. The existence of dead zone in the process will make the process variable deviate from the original set point. Therefore, the output of the controller is increased enough to overcome the dead zone, and only this corrective action will occur.

2、①影响死区的主要因素。摩擦力、游移、阀轴扭转、放大器的死区。各种控制阀对摩擦里敏感是不一样的,比如旋转阀对于由高的阀座负载引起的摩擦力就非常敏感,故使用时注意到这一点。但是对于有些密封型式,高的阀座负载是为了获得关闭等级所必须的。哈哈,这样,这种阀设计出来就非常差,容易引起很大的死区,这对过程偏差度的影响是显而易见的,简直是决定性的。

2. ① main factors affecting dead zone. Friction, travel, valve shaft torsion, dead band of amplifier. The sensitivity of various control valves to friction is different. For example, the rotary valve is very sensitive to the friction caused by high seat load, so pay attention to this when using. However, for some seal types, a high seat load is necessary to obtain a closing grade. Haha, in this way, the design of this valve is very poor, which is easy to cause a large dead zone, which has an obvious and decisive impact on the process deviation.

②磨损。阀门在正常使用时出现磨损是在所难免的,但是润滑层的磨损是厉害的的,根据我们实验证实,润滑旋转阀只经过几百次循环动作,润滑层差不多可以刚刷子使用(夸张点,不然写文章很郁闷)。另外压力引起的负载也会导致密封层的磨损,这些都是导致摩擦力增加主要因素。结果呢?就是给控制阀的性能于毁灭性!

② Wear and tear. Wear of the valve during normal use is inevitable, but the wear of the lubricating layer is severe. According to our experiments, the lubricating rotary valve only goes through hundreds of cycles, and the lubricating layer can almost be used with a brush (exaggeration, otherwise the article is very depressed). In addition, the load caused by pressure will also lead to the wear of the sealing layer, which are the main factors leading to the increase of friction. What happened? Is to give the performance of the control valve to destruction!

③、填料摩擦力是控制阀摩擦力的主要来源,使用的填料不同,造成的摩擦力有很大的差别。

③ Packing friction is the main source of friction of control valve. The friction caused by different packing is very different.

④、执行机构的类型不同也对摩擦力有根本性的影响,一般来说弹簧薄膜执行机构比活塞执行机构好。

④ Different types of actuators also have a fundamental impact on friction. Generally speaking, spring membrane actuators are better than piston actuators.