Common Faults and Troubleshooting Methods for PE Ball Valves

　　PE ball valves may experience internal leakage during operation or installation due to factors such as frequent opening and closing during use, or improper installation that does not comply with the specified requirements. PE ball valve It is not functioning properly. Here, we will explain the causes of internal leakage in PE ball valves and the corresponding troubleshooting methods.

　　I. Causes of Internal Leakage in PE Ball Valves

　　1. Causes of Internal Valve Leakage During PE Ball Valve Installation

　　(1) Improper transportation and lifting result in overall damage to the valve, leading to internal leakage;

　　(2) Upon shipment, the valve was not dried and protected against corrosion after hydrostatic pressure testing, resulting in corrosion of the sealing surfaces and internal leakage.

　　(3) Inadequate site protection: blind flanges were not installed at both ends of the valve, allowing rainwater, sand, gravel, and other contaminants to enter the valve seat and cause leakage.

　　(4) During installation, grease was not injected into the valve seat, resulting in contaminants entering the rear portion of the seat or damage during welding, which in turn caused internal leakage.

　　(5) The valve was not fully open during installation, resulting in damage to the ball. During welding, if the valve is not in the fully open position, weld spatter can strike the ball, causing internal leakage.

　　2. PE ball valve Causes of Internal Valve Leakage During Operation

　　(1) A common cause is that operations managers, considering maintenance costs to be relatively high, fail to perform valve maintenance, or lack systematic valve management and maintenance practices as well as preventive maintenance procedures, resulting in premature equipment failure.

　　(2) Prolonged lack of maintenance or movement of the valve can cause the valve seat and ball to become locked, resulting in seal damage and internal leakage during valve opening and closing;

　　(3) Incomplete valve actuation can lead to internal leakage. For any PE ball valve, regardless of whether it is in the open or closed position, there is typically a tilt of 2 to 3 degrees, which may result in leakage.

　　(4) Many large-diameter PE ball valves are equipped with a valve stem stop. With prolonged use, rust and other contaminants such as dust and paint can accumulate between the valve stem and the stop, preventing the valve from fully rotating into its closed position and resulting in leakage.

　　(5) In electric actuator-equipped valves, improper valve positioning at the start can result in internal leakage; moreover, inadequate regular maintenance and servicing can cause the sealing grease to dry out and harden, with the dried grease accumulating behind the elastomeric seat and obstructing its movement, thereby leading to seal failure.

　　II. PE ball valve Leak Handling Procedure

　　1. First, check the limit settings of the PE ball valve to determine whether adjusting these limits can resolve internal leakage. Inject a measured amount of grease to see if it can stop the leak. During this process, the injection rate must be slow. At the same time, monitor the pressure gauge at the grease injection gun outlet to assess the extent of the valve’s internal leakage.

　　2. If the leak cannot be stopped, it may be due to hardening of the seal grease injected during the initial filling or damage to the sealing surfaces, resulting in internal leakage. In this case, it is recommended to inject a valve cleaning fluid to clean the valve’s sealing surfaces and seat. Once the hardened deposits have completely dissolved, proceed with the next step of treatment.

　　3. Re-inject lubricant, intermittently open and close the valve to purge impurities from the back cavity of the valve seat and the sealing surfaces.

　　4. Verify that the valve is fully closed. If leakage persists, inject enhanced sealing grease and then open the valve bonnet to vent the cavity, which will create a significant pressure differential to aid sealing. Under normal conditions, this procedure should eliminate internal leakage caused by the enhanced sealing grease.

　　5. If internal leakage persists, repair or replace the PE ball valve.