Automatic Line Break Control
 |
For Main Line Valve Protection
The unique Shafer Automatic Line Break Control operates on a diaphragm principle to automatically close main pipeline valves in the event of excessive sustained drop in line pressure. It reacts seconds after a break occurs and only to a sustained rate of pressure drop. A "lost motion" feature causes any short, sudden drop to be absorbed without tripping the control. As a safety factor, the control is usually furnished so that the valve must be manually reopened.
For River Crossing Protection
River crossings are usually the weak points of high pressure gas transmission systems. It is desirable to resort to dual lines when crossing a river; when one of the lines fails the remaining line will carry the flow after the defective line is shut off for repairs. Rapid manipulation of the valves controlling the crossing is required. Valves equipped with Shafer Automatic Line Break Controls will perform this function with the most speed and reliability available.
In the event of a rupture, all valves will immediately close, isolating and starving the ruptured line. The Shafer Automatic Line Break for River Crossing protection, however, will react to a predetermined static pressure, and reopen the unbroken line to ensure uninterrrupted flow of gas.