Question: How is a valve operability inspection check made on a distribution system valve?
Answer: First and foremost, the company’s operating and maintenance procedures must be followed! Company procedures may include the following tasks: Verification that all valve information is accurate; a leak test performed using a CGI; valve accessibility check (i.e., key placed on valve to verify that the valve actuator (stem) can be accessed through valve B-box); valve tag number identification; and the operability check (if applicable).
If a distribution valve operability check is required, the valve is usually partially closed (e.g., no more than a 1/8th of a turn) and immediately returned to the full open position. If the valve cannot be returned to full open position or is found inoperable, the employee should report an abnormal operating condition. Follow-up repair or replacement will be required to correct the situation.
Tip: Prior to any valve operability check, precautions should be taken to prevent service outages or overpressuring the system. This may include documenting the valve type, direction, number of turns for operation, verifying orientation of the valve to the valve stops, and downstream pressure monitoring.