Is the valve actually leaking? In most cases, the leaking is caused by an outside source affecting the valve.
A few troubleshooting questions that may help address this issue are:
Is this a new installation or repair?
Is the valve installed vertically?
Is the installation piping (inlet and outlet) correct?
Has the system been recently changed or modified (including the valve manufacture and model)?
Is a proper operating gap being maintained?
Have pressure-measuring devices been calibrated recently?
Where is the pressure measurement being sampled in relationship with the valve and is there a correction required for pressure differences between the two areas?
Does the valve exhaust into a single exhaust or a common header?
Is the system seeing any vibration?
Was the valve opened in an over-pressure condition? If so, how many times?
My plant I faced that problems.
Main dil.line header taken 5bar pressure. That same line 4inch tapping arranged and mounted that auto valve,every 30min one time dil.line valve open and close.
A leaking valve can have various causes, and troubleshooting the issue requires a systematic approach.
Valve Leaking
Here are some common reasons why a valve may be leaking:
Improper Valve Seating: The valve may not be fully closed or seated properly, leading to leakage. This can happen due to valve wear, misalignment, or damage to the sealing surfaces. Inspect the valve for any visible damage or misalignment and consider reseating or replacing the valve if necessary.
Seal or Gasket Failure: Valves often have seals or gaskets to prevent leakage. Over time, these seals can degrade, harden, or become damaged, leading to leaks. Check the seals or gaskets for wear or damage and replace them if needed.
Dirt or Foreign Objects: Debris or foreign objects in the valve body or seat can prevent proper closure, causing leakage. Clean the valve thoroughly and remove any obstructions or particles that may be affecting the valve’s ability to seal.
Overpressure: Excessive pressure beyond the valve’s rated capacity can cause leakage. Check if the pressure upstream or downstream of the valve is within the recommended range. If the pressure exceeds the valve’s rating, consider installing a pressure relief device or upgrading the valve to handle the required pressure.
Corrosion or Erosion: Corrosion or erosion of valve components, such as the valve body, stem, or seating surfaces, can lead to leakage. Inspect the valve for signs of corrosion or erosion, and if found, consider replacing or repairing the affected components.
Improper Installation or Assembly: Incorrect installation or improper assembly of the valve can result in leaks. Check if the valve is installed according to the manufacturer’s instructions, including proper alignment, torque specifications, and use of appropriate sealants or thread tape.
Temperature Effects: Extreme temperatures can cause expansion or contraction of valve components, leading to leaks. Ensure that the valve is suitable for the temperature conditions in which it is operating, and consider using insulation or heat-resistant materials if necessary.
Wear and Tear: Valves undergo regular wear and tear over time, especially in high-usage applications. Seals, packing, or other components may deteriorate, resulting in leakage. Regular maintenance, inspection, and replacement of worn parts are necessary to prevent leaks.
Improper Valve Sizing: If the valve is undersized for the application, it may not be able to handle the required flow or pressure, leading to leaks. Consider consulting with a valve specialist or engineer to ensure that the valve is correctly sized for the specific application.
It’s important to note that the specific cause of valve leakage may vary depending on the valve type, application, and operating conditions. If troubleshooting the issue yourself proves challenging, consider seeking assistance from a qualified valve technician or engineer who can provide a more accurate diagnosis and recommend appropriate solutions.