In the process of using the valve, there are often some troublesome problems, such as the valve can not be closed tightly and tightly. What should we do? In general, if it is not tightly closed, first confirm whether the valve is closed in place. If there is still leakage and cannot be sealed after it is closed in place, then check the sealing surface. If the sealing pair of some valves is removable, take it out for grinding and retest. Of course, if it is still not tightly closed, Then it is necessary to return to the factory for maintenance or replace the valve, so as not to affect the normal use of the valve and cause working condition accidents. If the valve fails to close tightly, first find out where the problem is, and then solve it according to the corresponding methods. There are several reasons why the valve cannot be closed tightly:

（1）有杂质卡在密封面，杂物沉积在阀门腐蚀处或垫在阀瓣与阀座之间；

(1) Impurities are stuck on the sealing surface, and sundries are deposited at the corrosion place of the valve or padded between the valve disc and the valve seat;

（2）阀杆螺纹生锈，阀门无法转动；

(2) The stem thread is rusty and the valve cannot rotate;

（3）阀门密封面被破坏，导致介质出现泄漏；

(3) The sealing surface of the valve is damaged, resulting in medium leakage;

（4）阀杆与阀瓣连接不好，使阀瓣与阀座偏斜不能严密接触。

(4) The connection between the valve stem and the valve disc is not good, so that the valve disc and the valve seat can not be in close contact.

阀门关不严的处理方法：

Treatment method for loose valve closing:

一、有杂质卡住阀门密封面

1、 Impurities stuck on the sealing surface of the valve

阀门有时突然关不严，可能是阀门密封面间有杂质卡住，此时不应用力强行关闭，应把阀门稍开大一些，然后再试图关闭，反复试试，一般即可排除，否则应进行检查，应保持介质的质量洁净。

Sometimes the valve suddenly fails to close tightly, which may be due to impurities stuck between the sealing surfaces of the valve. At this time, do not force it to close. Open the valve slightly larger, and then try to close it again and again. Generally, it can be eliminated by trying again and again. Otherwise, it should be checked and the quality of the medium should be kept clean.

二、阀杆螺纹生锈

2、 Stem thread rusted

对于通常在开启状态的阀门，偶然关闭时，由于阀杆螺纹已经生锈，也会发生关不严的情况。对于这种情况，可反复开关几次阀门，同时用小锤敲击阀体底部，即能将阀门关严，无需对阀门进行研磨修理。

For the valve that is usually in the open state, when it is closed accidentally, the valve stem thread will be rusted and the valve will not be closed tightly. In this case, the valve can be opened and closed several times and the bottom of the valve body can be knocked with a small hammer at the same time, so that the valve can be closed tightly without grinding and repairing the valve.

三、阀门密封面被破坏

3、 The sealing surface of the valve is damaged

对于试着多次开关仍然关不紧的情况，那就是密封面已损坏了，应报修；又或者腐蚀、介质中的颗粒划伤等破坏了密封面，也应报修。

If the switch cannot be closed tightly after trying for many times, that is, the sealing surface has been damaged and should be reported for repair; If the sealing surface is damaged by corrosion or particle scratch in the medium, it shall also be reported for repair.

四、阀杆与阀彩连接不好

4、 Poor connection between valve stem and valve color

经常给阀杆和阀杆螺母加润滑油，以保证阀门的开关灵活，要有一套维护方案。

Often add lubricating oil to the valve rod and valve rod nut to ensure the flexible opening and closing of the valve, and there should be a set of maintenance scheme.