Gate Valves are the most commonly used valve type in the industry. It is intended for on-off flow control. Any attempt to use in a partially opened position for throttling could result in chattering, excessive wear and rapid erosion of the disc and seat, and impair its ability to close tightly. Globe Valves are used for throttling flow control. Shut-off is accomplished by moving the disc against the flow stream rather than across it. This reduces chatter, wear & erosion to a minimum. The flow pattern through a globe valve involves changes in direction, resulting in greater resistance than a gate valve. The Swing Check Valve is used to prevent back flow in the process line. Flow is in a straight line through the valve resulting in minimal pressure drop.