电动调节阀的外漏处理五个小窍门
Five tips to deal with leakage of electric control valve
方法一，增加密封油脂法;这种方法是针对还未使用密封油脂的阀体，可以考虑增加密封油脂来提高阀杆的密封性能的。平时日常维护电动调节阀的时候，增加补充密封油脂也是必要的维护程序之一。
The first method is to increase the sealing grease method; this method is for the valve body which has not used the sealing grease, so it can be considered to increase the sealing grease to improve the sealing performance of the valve stem. When daily maintenance of electric control valve, adding sealing grease is also one of the necessary maintenance procedures.
方法二，改变流向，置P2在阀杆端法;当△P较大,P1又较大时,密封P1显然比密封P2困难.因此,电动调节阀可采取改变流向的方法,将P1在阀杆端改为P2在阀杆端,这对压力高、压差大的阀是较有效的.如波纹管阀就通常应考虑密封P2。
The second method is to change the flow direction and place P2 on the stem end. When the △ P is larger and P1 is larger, it is obviously more difficult to seal P1 than P2. Therefore, the electric control valve can adopt the method of changing the flow direction, changing P1 to P2 at the stem end, which is more effective for valves with high pressure and large pressure difference. For example, the bellows valve should usually consider sealing P2.
方法三，采用透镜垫密封法;对于上、下盖的密封,阀座与上、下阀体的密封.若为平面密封,在高温高压下,密封性差,引起外泄,可以改用电动调节阀透镜垫密封,能得到满意的效果。
The third method is to use lens gasket sealing method; for the sealing of upper and lower covers, the sealing between valve seat and upper and lower valve bodies. If it is plane sealing, the sealing performance is poor under high temperature and high pressure, resulting in leakage, so the lens gasket seal of electric control valve can be used, and satisfactory results can be obtained.
方法四，增加填料法;通常是采用双层或者多层混合填料的形式单纯地增加密封垫片的数量，如将3片增加到5片，来提高阀杆的密封性能，不过电动调节阀防漏效果不是很明显。
The fourth method is to increase the packing method, which is usually in the form of double-layer or multi-layer mixed packing, simply increasing the number of sealing gaskets, such as increasing 3 pieces to 5 pieces, to improve the sealing performance of the valve stem, but the leakage proof effect of the electric control valve is not very obvious.
方法五，是更换石墨填料法;大量被使用的四**填料，其适用工作温度在-20～200℃范围内，当工作温度在上限、下限变化较大时，电动调节阀密封性能便明显下降了，且老化快，寿命短。这里推荐使用柔性石墨填料可以克服四**填料所不能承受的困难，且使用寿命长，从而提高密封的可靠性。有很多工厂已经全部将四**填料改为石墨填料了，甚至新购买的调节阀也将其中的四**填料换成石墨填料后使用。但是石墨填料也有个缺点，就是回差大，初时有的还产生爬行现象，对此，生产商和使用商在设计安装电动调节阀设备时也要有所考虑。
The fifth method is to replace graphite packing method; a large number of used four * * fillers can be used in the range of - 20 ~ 200 ℃. When the working temperature changes greatly in the upper and lower limits, the sealing performance of the electric control valve decreases obviously, and the aging is fast and the service life is short. The flexible graphite packing is recommended here, which can overcome the difficulties that the four * * packing can not bear, and has a long service life, so as to improve the reliability of the seal. Many factories have changed the packing of four * * into graphite packing, and even the newly purchased regulating valve has replaced the four * * packing with graphite packing. However, graphite packing also has a disadvantage, that is, the return difference is large, and some of them still have crawling phenomenon at the beginning. Therefore, manufacturers and users should also consider the design and installation of electric control valve equipment.
