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Common Butterfly Valve Failures, Causes and Practical Solutions
2026-07-03
Under the long-term effects of pressure fluctuations, high temperatures, corrosive media, and particulate wastewater, butterfly valve may experience various malfunctions, including internal leakage, external leakage, jamming, abnormal noise, and actuator failure.
This article sorts out typical failures of concentric soft seal butterfly valves, triple eccentric metal seated butterfly valve, pneumatic butterfly valve and electric butterfly valve, analyzing root causes and offering targeted solving methods for on-site maintenance staff.
1. Internal leakage is the most frequent fault for soft seat butterfly valves. The main triggers include aging, scratch or deformation of rubber sealing liner, sediment and solid particles stuck between disc and valve seat, and incomplete valve closing stroke.
Solutions: Clean impurities on the sealing surface thoroughly; replace damaged EPDM rubber liner; adjust the worm gear or actuator stroke to ensure full closure. For metal seated triple eccentric butterfly valves, internal leakage usually results from worn hardfacing layers, which needs on-site re-surfacing or replacement of the valve disc assembly.
2. External leakage appears at valve stem, flange connection and bonnet joint. Stem leakage is caused by aging packing and insufficient compression; flange leakage comes from loose bolts or damaged gaskets.
Maintenance solutions: Tighten stem packing gland evenly and replace aging PTFE packing; re-tighten flange bolts symmetrically and replace cracked anti-corrosion gaskets.
3. Stuck or difficult operation happens when the butterfly valve cannot open or close smoothly. Root causes: Rust between valve stem and sleeve, excessive sediment locking the disc, improper torque setting of worm gear. Staff can disassemble the valve for internal cleaning, polish rusted stem parts and adjust the worm gear torque to restore flexible switching.
4. Vibration and abnormal noise during operation mainly exist in large-diameter pipeline butterfly valves. Fast medium flow, mismatched opening angle and loose connecting parts lead to loud vibration noise. Solutions: Adjust valve opening to reduce flow velocity; reinforce pipeline supports; fasten all loose connecting bolts of valve body and actuator.
5. Pneumatic and electric butterfly valve actuator failures, such as no response to control signals, incomplete switching and air leakage of air cylinder.
For pneumatic models, inspect air source pressure, solenoid valve and air cylinder seals; for electric actuators, check power supply, limit switches and motor circuits, replace damaged control components if necessary.
| Common Failures | Root Causes | Solutions |
|---|---|---|
| Internal Leakage in Valve Body | Aging, scratching or deformation of rubber lining; sediment/solid particles stuck between the disc and valve seat; insufficient valve closing stroke | Clean impurities on the sealing surface thoroughly; replace the damaged EPDM rubber lining; adjust the stroke of the worm gear or actuator to ensure full valve closure |
| Stem External Leakage | Aging of valve stem packing; loose compression of the packing gland | Tighten the packing gland evenly; replace the aged PTFE valve stem packing |
| Flange Water Seepage | Damaged sealing gasket; uneven tightening of flange bolts | Replace the cracked or damaged anti-corrosion sealing gasket; tighten the flange bolts symmetrically and evenly |
| Stuck or Unsmooth Operation | Rust on the valve stem and sleeve; excessive sediment locking the butterfly disc; improper torque setting of the worm gear | Disassemble the valve for internal cleaning; polish and derust the rusted valve stem; adjust the worm gear torque to restore flexible switching |
| Vibration and Abnormal Noise During Operation | Excessive medium flow velocity; mismatched valve opening angle; loose pipeline supports and connecting parts | Adjust the valve opening to reduce flow velocity; reinforce the pipeline support structure; fasten all loose connecting bolts of the valve body and actuator |
| Pneumatic/Electric Butterfly Valve Fails to Operate | Insufficient air source pressure; circuit failure; damaged limit switch or control component | Inspect and repair the air source, solenoid valve and cylinder seals for pneumatic models; check the power supply, motor and limit switches for electric models; replace damaged control components if necessary |
In conclusion, regular inspection and routine maintenance can greatly reduce butterfly valve failure rate. Matching correct valve type according to medium temperature, pressure and cleanliness can avoid premature sealing damage, extend the service life of wafer butterfly valve, flange butterfly valve and metal seated butterfly valve, and guarantee stable pipeline operation.
KR VALVE (TIANJIN) Co., LTD
Email: info@tjkrvalve.com
Telephone: 0086 18920615838