Menu
| Sr.No. | Description of trouble | Probable cause | Possible Solution |
| 1 | Less than rated or no valve travel even though proper air pressure is applied to actuator diaphragm. | 1. No air signal or incorrect air signal to actuator | 1.Check the controller and correct. |
| 2. Air leakage through the tube wall or connections | 2.Check the piping system and repair. | ||
| 3.Rupture on the actuator diaphragm. | 3.Replace diaphragm. | ||
| 4. Dirt or foreign matters restricting rotor movement | 4.Disassemble valve, clean and polish trim parts. | ||
| 2 | Leakage at Body Joint. | 1.Improper Tightening of the Body-Bonnet Joint. | 1.Tighten the bolts in a consistent manner. |
| 2. Damage to the body and bonnet flange’s sealing surface. | 2.Repair the sealing surface of the body or bonnet where damage is observed. | ||
| 3. Gasket failure or metal sealing ring damage. | 3.Replace or replace the gasket or metal sealing ring. | ||
| 3 | Leakage around valve stem. | 1. Wear or damage on the packing. | 1.Replace packing. |
| 2. Extreme wear or damage on the valve stem. | 2.Replace valve stem. | ||
| 4 | Inadequate flow | 1.Improper plug adjustment | 1.Refer ‘ASSEMBLY OF VALVE’ section of the manual shared |
| 2.Malfunctioning valve positioner | 2.Bypass valve positioner and check valve operation with direct signal | ||
| 3.Service conditions exceeds trim design capacity | 3.Reconfirm service conditions and contact factory | ||
| 5 | Control valve hunting | 1.Input signal fluctuations | 1.Provide steady signal through controller |
| 2.Backlash error in moving parts | 2.Remove backlash | ||
| 3.Moisture in air line | 3.Provide dry air supply | ||
| 4.Improper tuning of controller | 4.Adjust the controller settings | ||
| 6 | Excessive noise | 1.Flashing or Cavitations | 1.To ensure that adequate care has been taken at design stage |
| 2.Loose supports | 2.Tighten the supports sufficiently | ||
| 3.Damaged trim assembly | 3.Replace the trim parts | ||
| 7 | Handwheel cannot be turned flexibly. | 1.Damage to the stem nut due to Dirt /Foreign Particle | 1.Replace the stem nut with a new one. |
| 2. Wear or perforation of the stem nut’s screw thread. | 2.Clean the debris from the screw thread of the stem nut. | ||
| 8 | Gland Leakage | 1. Packaging is not sufficiently tightened (Gland Nut Loose). | 1.Equally tighten the Gland nut. |
| 2. Worn out Gland Packing. | 2.Change the packing with a fresh one. | ||
| 9 | Seat Leakage | 1. Sealing Edge of Seat Damaged | 1.Replace Soft Seat. |
| 2. Valve Pressurized to High Pressure. | 2.Reduce Line pressure to rated Pressure. | ||
| 3. Fluid is abrasive & Eroding away Seal. | 3.Replace worn-out parts suitable with abrasive Media |
Subscribe to our Newsletter & Event right now to be updated
Uniflow Controls Pvt. Ltd.
B Wing, 303, Mahavir Icon ,
Sector-15, CBD Belapur, Navi Mumbai
Maharashtra 400614, India