Purpose of block valves?

• A. Start or stop flow
• B. Increase pressure
• C. Filter debris
• D. Measure flow

Answer: (A)

Block valves are used to provide a positive shut-off in a pipeline, allowing you to start or stop the flow by fully opening or fully closing the line. This lets you isolate a section for maintenance, perform safe work, or respond quickly in an emergency. They create a clear barrier so fluid doesn’t pass when the valve is closed. This is different from devices that raise pressure, filter debris, or measure flow, which are handled by pumps/regulators, filters, and flow meters. In practice, you close the valve to stop flow and open it to allow flow again, ensuring safe isolation of equipment when needed.