Essential Guide to Operating and Maintaining Fixed Ball Valves

 
Fixed ball valves are commonly used in various industrial sectors, including oil, natural gas, chemicals, and water treatment. They control the flow of media within pipelines by rotating a spherical element. These ball valves are known for their quick operation, excellent sealing, and ease of use. To ensure the safety and effectiveness of the ball valves, strict adherence to operational procedures and maintenance requirements is essential. Below is a detailed guide on the operation and maintenance of fixed ball valves.

Preparation Before Maintenance

 
Fixed ball valves are designed with a stationary ball that rotates to open or close the valve. The ball is supported by two valve seats that move towards the ball under pressure, ensuring a good seal. These valves can be operated manually, electrically, or pneumatically, allowing for rapid opening and closing as well as automated control, making them suitable for high-pressure and large-diameter pipeline systems. Before performing maintenance on a fixed ball valve, thorough preparation is necessary to ensure safety.
 
Relieving Pipeline Pressure: Even when the fixed ball valve is closed, pressurized fluid may remain inside the valve body. To prevent accidents, it is crucial to relieve the pipeline pressure and ensure the valve is in the open position.
 
Disconnecting Power and Gas Supply: Before maintenance, disconnect the power or gas supply and detach the actuator from the bracket to avoid accidental activation.
 
Clearing Environmental Obstacles: Ensure the operation area is clean and free of debris and that necessary safety measures are in place.

Maintenance and Cleaning Requirements

Regular maintenance and cleaning are key to ensuring the long-term reliable operation of fixed ball valves. Routine maintenance helps extend the valve's service life and reduces the likelihood of malfunctions.
 
Disassembly and Cleaning: Before disassembling the fixed ball valve, ensure that the pressure in the upstream and downstream pipelines has been fully released. During disassembly and reassembly, care must be taken to avoid damaging the sealing surfaces of the components. Non-metallic parts should be removed immediately after cleaning and should not be left soaking in cleaning agents for extended periods. After cleaning, allow the cleaned parts to dry completely before reassembly to prevent rust or contamination from dust.
 
Choosing the Right Cleaning Agent: The cleaning agent must be compatible with all materials of the fixed ball valve, including rubber, plastic, and metal components, as well as the working medium, such as gas. For example, metal parts can be cleaned with gasoline, while non-metallic parts should be cleaned with purified water or alcohol.
 
Lubrication and Assembly: During assembly, apply a thin layer of appropriate lubricant on the surfaces of the sealing groove, rubber seals, and the stem's sealing and friction surfaces. The lubricant should be compatible with the valve's materials and working medium; for example, Molykote 221 grease is suitable for gas applications. When assembling, the flange bolts must be tightened symmetrically, progressively, and evenly to ensure good sealing performance.

Operating Procedures and Precautions

Operators must strictly follow the procedures to ensure the safe and proper functioning of fixed ball valves.
 
Avoid Overload Operation: Do not operate the ball valve beyond its designed pressure and temperature range to prevent equipment damage or accidents.
 
Safety Measures: Operators should wear appropriate protective gear, such as gloves and goggles, to protect against high temperatures or harmful media.
 
Regular Inspection and Maintenance: Perform regular inspections and maintenance on fixed ball valves, including checking sealing performance, operational performance, and whether the connecting bolts are loose. Any issues found should be addressed promptly to ensure the valve's proper operation.
 
Lubrication Maintenance: For fixed ball valves requiring lubrication, select the appropriate lubricant according to the usage instructions and perform lubrication maintenance to ensure valve flexibility and sealing performance.

Common Issues and Troubleshooting

During use, fixed ball valves may encounter common issues such as seal failure or inflexible operation. When these situations arise, appropriate corrective measures should be taken promptly:
 
Seal Failure: If the valve's sealing performance deteriorates, first check for wear or dirt on the sealing surface. Cleaning or replacing the seals can restore sealing performance.
 
Inflexible Operation: If the ball valve is difficult to operate, it may be due to poor lubrication or internal component blockage. A thorough inspection should be conducted, and if necessary, parts should be cleaned or replaced, and the valve should be relubricated.
 
Abnormal Noise or Vibration: If abnormal noises or vibrations are observed during operation, it may indicate loose or damaged internal components. Operation should be stopped immediately for a detailed inspection.
 
Fault Handling: When abnormal conditions are detected in the fixed ball valve, prompt fault handling is required. Conduct a comprehensive inspection based on the abnormal symptoms to identify the cause and perform repairs. If the issue cannot be resolved independently, contact professional personnel for maintenance.
 
Proper operation and maintenance of fixed ball valves are crucial for ensuring their long-term, stable operation. Regular inspections, correct cleaning, and appropriate lubrication can effectively extend the service life of ball valves and ensure they operate reliably and safely under various conditions. Strict adherence to operational procedures and maintenance requirements not only enhances production efficiency but also effectively prevents safety accidents caused by equipment failures.