| 摘要 |
<p>A breakaway pipe coupling comprising first and second telescoping pipe sections that are joined together by a load control mechanism designed to release in a controlled manner at a predetermined axial load. The load control mechanism, which may assume the form of a cutter ring carried by one pipe section and which bears against the exterior of the other section, or may be a plurality of external cylinders housing cutter rings attached to one pipe section which bear against rods passing through the cylinders and attached to the other pipe section. Such a load control mechanism holds the pipe sections together up to a certain predetermined tension load. A valve is disposed within the first pipe section and is joined by a crank and a rod to a second pipe section so that when the pipe sections are joined together, the valve is retained in an open position and fluid can freely flow through the coupling. When the pipe sections separate, the valve is closed to prevent fluid flow. When the coupling is subjected to a tensile force exceeding the predetermined tension load, the load control mechanism yields in a controlled manner by the action of the cutting ring(s) shearing material from the surface on which it bears. The sections separate at a rate proportional to the rate at which tension is applied. As the sections separate, the valve closes so that the contents of the pipeline are not discharged into the environment.</p> |
