In industrial and domestic environments, the operational status of valves, a key component in controlling the flow of fluids, is critical. However, valves can encounter a variety of problems. This article will introduce you to some common valve failures and their easy-to-understand solutions to help you quickly respond to ensure smooth operation of the system.
First, the valve leakage: the art of dripping
- Internal leakage: valve off the water leakage?
Phenomenon: the valve is clearly closed, but the medium is still quietly flowing inside.
Possible causes: wear and tear of the sealing surface, corrosion or impurities; valve stem bent, resulting in the valve and valve seat can not close; the valve is selected wrong, the pressure level or sealing form does not meet the requirements.
Solutions: grinding or new sealing surface; straighten the valve stem or new; re-pick a suitable valve for replacement. - external leakage: valve dripping outside?
Phenomenon: packing box, flange connection or valve body with media leakage.
Possible causes: packing aging, wear and tear or not installed; flange gasket is bad; the valve body has sand holes, cracks; installation bolts are not tightened or connection is not standardized.
Solution: change the new packing and correct installation; change the new flange gasket; repair or replace the valve body; reinstall the valve to ensure that the bolts are tightened and connected to the standard.
Second, the valve switch is not smooth: easy to switch the small tips - opening difficult: the valve can not open?
Phenomenon: the valve is difficult to open, and sometimes even motionless.
Possible causes: valve stem rust or stuck; valve valve and valve seat between foreign objects; valve too long useless, the sealing surface is sticky; transmission mechanism has a problem, such as gear wear.
Solution: remove rust, lubricate the valve stem; remove foreign objects; gently tap the valve to make it loose; check the transmission mechanism, repair or replace worn parts. - closed poorly: the valve is not tight?
Phenomenon: After the valve is closed, the medium is still leaking.
Possible causes: the sealing surface is bad; stem bent or shifted; closing speed is too fast, hurt the sealing surface; impurities in the medium blocked the valve.
Solution: grind or replace the sealing surface; correct the valve stem; slowly close the valve; clean up the impurities in the valve.
Third, the valve vibration and noise: the secret of quiet running
Phenomenon: abnormal vibration and noise emitted when the valve is running.
Possible causes: the valve selected wrong, such as flow, pressure mismatch; pipe support instability; medium flow rate is too fast; valve internal parts loose or bad.
Solutions: change a suitable valve; strengthen the pipe support; adjust the media flow rate, such as increasing the diameter of the pipeline or installation of throttling devices; check the internal parts of the valve, fastening or replacement of damaged parts.
Fourth, the valve corrosion: the main points of rust and corrosion resistance
Phenomenon: valve body, valve stem, valve valve rust, corrosion or pitting.
Possible causes: corrosive medium; valve material is not suitable; the environment is humid or corrosive gases; anti-corrosion coating is bad.
Solution: according to the medium corrosive selection of suitable corrosion-resistant valves; anti-corrosion treatment of the valve, such as anti-corrosion paint; improve the environment, such as strengthening ventilation; repair or replacement of damaged anti-corrosion coating.
Fifth, stuffing box leakage: drip maintenance
Phenomenon: packing box at the media leakage, and the leakage is getting bigger and bigger.
Possible reasons: packing is not pressed or filling method is not correct; packing aging; valve stem surface roughness; packing box design is not reasonable.
Solutions: re-pressure packing or correct filling; new packing; grinding valve stem; improve the design of the packing box, such as increasing the sealing ring.
Sixth, electric and pneumatic valve failure: electric and pneumatic wisdom - electric valve failure: electric not move?
Phenomenon: electric valve can not be electrically opened or closed, or inaccurate position.
Possible causes: power supply problems, such as power outages, unstable voltage; bad motor; control circuit failure; electric actuators have problems.
Solutions: check the power supply and restore; repair or replace the motor; check and repair the control circuit; check and repair the electric actuator. - pneumatic valve failure: pneumatic does not work?
Phenomenon: Pneumatic valve can not be pneumatically opened or closed, or abnormal speed.
Possible causes: insufficient or unstable pressure of the air source; pneumatic actuator problems, such as cylinder leakage; pneumatic control element failure; problems with the internal components of the valve.
Solutions: Check the air source and make sure the pressure is stable; repair or replace the pneumatic actuator; check and repair the pneumatic control element; check and repair the internal parts of the valve.
With the above guide, we hope to help you better understand and solve the various problems encountered in the operation of the valve to ensure the smooth and safe operation of your industrial and domestic systems.