After the valve has been running in the pipeline network for a period of time, various failures will occur. The number of reasons for the failure of the valve is related to the number of parts that make up the valve. If there are more parts, there will be more common failures; Installation, working condition operation, and maintenance are related to each other. Generally, the common failures of non-power driven valves can be roughly divided into the following four categories.
1. The valve body is damaged and ruptured
Reasons for valve body damage and rupture: Decreased corrosion resistance of valve material; pipeline foundation settlement; large changes in pipe network pressure or temperature difference; water hammer; improper operation of closing valves, etc.
The external cause should be eliminated in time and the same type of valve or valve should be replaced.
2. Transmission failure
Transmission failures often manifest as stuck stems, stiff operation, or inoperable valves.
The reasons are: the valve is rusted after being closed for a long time; the valve stem thread or stem nut is damaged by improper installation and operation; the gate is stuck in the valve body by foreign matter; The valve stem screw and the valve stem nut wire are misaligned, loosened, and seized; the packing is pressed too tightly and the valve stem is locked; the valve stem is pushed to death or stuck by the closing member.
During maintenance, the transmission part should be lubricated. With the help of a wrench, and lightly tapping, the phenomenon of jamming and jacking can be eliminated; stop the water for maintenance or replace the valve.
3. Poor valve opening and closing
The poor opening and closing of the valve is manifested by the fact that the valve cannot be opened or closed, and the valve cannot operate normally.
The reasons are: the valve stem is corroded; the gate is stuck or rusted when the gate is closed for a long time; the gate falls off; foreign matter is stuck in the sealing surface or sealing groove; the transmission part is worn and blocked.
When encountering the above situations, you can repair and lubricate the transmission parts; open and close the valve repeatedly and shock foreign objects with water; or replace the valve.
4. The valve is leaking
The leakage of the valve is manifested as: leakage of the valve stem core; leakage of the gland; leakage of the flange rubber pad.
The common reasons are: the valve stem (valve shaft) is worn, corroded and peeled off, pits and shedding appear on the sealing surface; the seal is aging and leaking; the gland bolts and flange connection bolts are loose.
During maintenance, the sealing medium can be added and replaced; new nuts can be replaced to readjust the position of the fastening bolts.
No matter what kind of failure, if it is not repaired and maintained in time, it may cause waste of water resources, and what is more, cause the entire system to be paralyzed. Therefore, valve maintenance personnel must be aware of the causes of valve failures, be able to adjust and operate valves proficiently and accurately, deal with various emergency failures in a timely and decisive manner, and ensure the normal operation of the water treatment pipe network.
Tianjin Tanggu Water-Seal Valve Co.,Ltd
Post time: Feb-24-2023