Ontario Operator-in-Training (OIT) Practice Exam

Which type of valve would you typically use to allow flow in one direction only?

1. Gate valve

2. Check valve

3. Butterfly valve

4. Globe valve

The correct answer is: Check valve

The type of valve specifically designed to allow flow in one direction only is the check valve. This valve operates with a mechanism that prevents backflow, ensuring that liquid or gas can only move in the intended forward direction. Check valves are particularly advantageous in systems where reverse flow could cause issues, such as in water supply or drainage systems, protecting the integrity of the piping and equipment. In contrast, gate valves are mainly used for stopping or starting flow rather than controlling the direction of flow. Butterfly valves, while effective for regulating flow, do not inherently prevent backflow. Globe valves are primarily designed for throttling flow and provide excellent control over flow rates but do not serve the purpose of allowing flow in only one direction. Understanding the distinct functions of various valves is crucial in engineering applications, especially in ensuring the right installation for operational efficiency and system protection.