| 摘要 |
<p>A shear valve has a body 1 which has an inlet 3 and an outlet 2, at opposite ends, a readily frangible or separable region 4, perhaps with reduced wall thickness, and an emergency shut-off valve 5 biassed toward the closed position enclosed in the inlet region, but held open by a displaceable abutment of at least one ball or roller. The ball may be held in position by a pointed member 8, and perhaps within a guide 10, and breakage or distortion of the valve body 1 causes relative displacement of the ball and the closure of the shut-off valve 5. The guide 10 may have a bore for the ball, and passageways 17 for the fluid, and may also be shaped to stop the ball. Pointed member 8 may be an insert provided with fluid passages. The second portion of the valve body 1 may have a non-return valve 14, perhaps with a thermal relief valve 16. The ball may also be released by a temperature actuated mechanism, 11 and 12. The valve is for use in fuel supply systems.</p> |
