Technical Support
Rotary Airlock Valve Maintenance and Overhaul
Regular maintenance helps rotary airlock valves and rotary feeders maintain stable discharge, sealing performance and long service life. Operators should pay attention to blockage, rotor jamming, lubrication and abnormal feeding conditions.
Daily Operation Checks
Check whether the discharge pipe is blocked and whether the impeller is jammed by material.
Remove foreign objects such as rope, wire, cement blocks, stones or other obstacles in time.
If material backs up or discharge becomes difficult, check the clearance between the impeller and the casing.
For valves with adjustable plates, adjust the clearance between the plate and the casing to reduce excessive axial or radial gaps.
Long-Term Shutdown
Before restarting after a long shutdown, rotate the impeller manually first to prevent failure caused by rust or sticking. Also check whether lubricating oil or grease needs to be added before operation.
Lubrication Reference
Worm gear reducers should be filled with W320 worm gear oil or suitable gear oil.
Directly coupled miniature cycloid reducers are filled with lithium grease before delivery. After three to six months of use, empty dirty grease and refill No. 00 lithium grease.
Bearing grease replacement interval is about 5,000 hours, depending on working conditions.
Add a small amount of grease to the chain when required.
If you experience repeated blockage, abnormal noise, material leakage or unstable discharge, contact FUWEI with your material information and operating conditions for troubleshooting support.
Repair, Rebuild and Troubleshooting Checklist
Check rotor tips, rotor-to-casing and end-cover clearances, shaft seals, bearings, reducer and motor when leakage, jamming, abnormal noise or unstable capacity occurs. For abrasive powder, worn clearance is a common reason for lower airlock performance.
| Problem | Possible Cause | Recommended Check |
|---|---|---|
| Air or material leakage | Worn rotor tips, enlarged clearance, damaged shaft seal or pressure imbalance. | Measure rotor-to-casing clearance, inspect seals, end covers and conveying pressure. |
| Rotor jamming | Foreign objects, hard lumps, caking, thermal expansion or insufficient clearance. | Clean the chamber, check contact marks, casing deformation, bearings and reducer, and confirm material moisture and particle size. |
| Low discharge capacity | Incorrect speed, bridging at inlet, outlet blockage or material buildup. | Check inlet flow, outlet pipe, rotor speed, reducer, material flowability, bulk density, rotor volume, filling rate, wear and material back pressure. Recalculate capacity and compare the current valve dimensions. |
| Noise or vibration | Bearing wear, shaft misalignment, reducer issue or rotor friction. | Inspect bearing temperature, coupling, reducer, motor load and rotor rub marks. |
| Fast wear | Abrasive powder, high speed, unsuitable material or coating damage. | Consider hardened rotor, tungsten carbide/PTFE coating or a lower operating speed. |
Repair, Rebuild or Replace?
Repair is suitable for seal, bearing, reducer or minor rotor issues when the casing is usable. Rebuild is suitable when rotor clearance and wear parts can be restored. Replacement is recommended if the casing is seriously worn, leakage cannot be controlled, rotor clearance cannot be restored, or the valve no longer matches process capacity and pressure conditions.
FAQ
What causes rotary airlock valve leakage?
Common causes include worn rotor tips, enlarged rotor-to-casing clearance, damaged shaft seals, pressure imbalance, end cover wear and material buildup inside the chamber.
When should a rotary airlock valve be rebuilt instead of replaced?
A rebuild is suitable when the casing is still usable and the issue is mainly rotor clearance, seals, bearings or reducer wear. Replacement is better when the body is seriously worn or the valve no longer matches the process capacity.
What should be checked when a rotary valve rotor jams?
Check for foreign objects, hard lumps, caking material, moisture, rotor contact marks, bearing condition and whether thermal expansion or incorrect clearance is causing friction.
Can FUWEI rebuild rotary airlock valves?
FUWEI can provide inspection suggestions, replacement guidance and customized rotary valve solutions based on photos, drawings and working conditions.
Information Needed for Repair Support
Send the valve size, flange size, rotor diameter, material name, capacity, working pressure and temperature, failure symptoms, photos of worn parts, drawings, and motor/reducer information. FUWEI can help check whether the valve should be repaired, rebuilt or replaced and help choose repair parts or a replacement rotary airlock valve.
Related Technical Guides and FUWEI Products
Rotary Airlock Valve Maintenance and Overhaul
Regular maintenance helps rotary airlock valves and rotary feeders maintain stable discharge, sealing performance and long service life. Operators should pay attention to blockage, rotor jamming, lubrication and abnormal feeding conditions.
Daily Operation Checks
Check whether the discharge pipe is blocked and whether the impeller is jammed by material.
Remove foreign objects such as rope, wire, cement blocks, stones or other obstacles in time.
If material backs up or discharge becomes difficult, check the clearance between the impeller and the casing.
For valves with adjustable plates, adjust the clearance between the plate and the casing to reduce excessive axial or radial gaps.
Long-Term Shutdown
Before restarting after a long shutdown, rotate the impeller manually first to prevent failure caused by rust or sticking. Also check whether lubricating oil or grease needs to be added before operation.
Lubrication Reference
Worm gear reducers should be filled with W320 worm gear oil or suitable gear oil.
Directly coupled miniature cycloid reducers are filled with lithium grease before delivery. After three to six months of use, empty dirty grease and refill No. 00 lithium grease.
Bearing grease replacement interval is about 5,000 hours, depending on working conditions.
Add a small amount of grease to the chain when required.
If you experience repeated blockage, abnormal noise, material leakage or unstable discharge, contact FUWEI with your material information and operating conditions for troubleshooting support.
Repair, Rebuild and Troubleshooting Checklist
Check rotor tips, rotor-to-casing and end-cover clearances, shaft seals, bearings, reducer and motor when leakage, jamming, abnormal noise or unstable capacity occurs. For abrasive powder, worn clearance is a common reason for lower airlock performance.
| Problem | Possible Cause | Recommended Check |
|---|---|---|
| Air or material leakage | Worn rotor tips, enlarged clearance, damaged shaft seal or pressure imbalance. | Measure rotor-to-casing clearance, inspect seals, end covers and conveying pressure. |
| Rotor jamming | Foreign objects, hard lumps, caking, thermal expansion or insufficient clearance. | Clean the chamber, check contact marks, casing deformation, bearings and reducer, and confirm material moisture and particle size. |
| Low discharge capacity | Incorrect speed, bridging at inlet, outlet blockage or material buildup. | Check inlet flow, outlet pipe, rotor speed, reducer, material flowability, bulk density, rotor volume, filling rate, wear and material back pressure. Recalculate capacity and compare the current valve dimensions. |
| Noise or vibration | Bearing wear, shaft misalignment, reducer issue or rotor friction. | Inspect bearing temperature, coupling, reducer, motor load and rotor rub marks. |
| Fast wear | Abrasive powder, high speed, unsuitable material or coating damage. | Consider hardened rotor, tungsten carbide/PTFE coating or a lower operating speed. |
Repair, Rebuild or Replace?
Repair is suitable for seal, bearing, reducer or minor rotor issues when the casing is usable. Rebuild is suitable when rotor clearance and wear parts can be restored. Replacement is recommended if the casing is seriously worn, leakage cannot be controlled, rotor clearance cannot be restored, or the valve no longer matches process capacity and pressure conditions.
FAQ
What causes rotary airlock valve leakage?
Common causes include worn rotor tips, enlarged rotor-to-casing clearance, damaged shaft seals, pressure imbalance, end cover wear and material buildup inside the chamber.
When should a rotary airlock valve be rebuilt instead of replaced?
A rebuild is suitable when the casing is still usable and the issue is mainly rotor clearance, seals, bearings or reducer wear. Replacement is better when the body is seriously worn or the valve no longer matches the process capacity.
What should be checked when a rotary valve rotor jams?
Check for foreign objects, hard lumps, caking material, moisture, rotor contact marks, bearing condition and whether thermal expansion or incorrect clearance is causing friction.
Can FUWEI rebuild rotary airlock valves?
FUWEI can provide inspection suggestions, replacement guidance and customized rotary valve solutions based on photos, drawings and working conditions.
Information Needed for Repair Support
Send the valve size, flange size, rotor diameter, material name, capacity, working pressure and temperature, failure symptoms, photos of worn parts, drawings, and motor/reducer information. FUWEI can help check whether the valve should be repaired, rebuilt or replaced and help choose repair parts or a replacement rotary airlock valve.
