| 摘要 |
PURPOSE:To improve the reliability of a relief action by providing a holding means holding a valve body at the closed position against the exciting force of an exciting means with the fluid pressure of the preset value or above in a valve box as a driving force. CONSTITUTION:When the fluid pressure in a valve box 13A connected to a fluid transporting pipe is the preset value or above, a valve body 13B is held at the closed position by a pressure receiving face 20 serving as a holding means with the fluid pressure as a driving force, and the release of the fluid in the valve box 13A is prevented. On the other hand, when the fluid pressure in the valve box 13A is decreased to the preset value or below, the holding force by the holding means 20 becomes smaller than the exciting force by a spring 18 serving as an exciting means, the valve body 13B is opened and moved, a fluid discharge port 13b is opened, and the fluid is discharged from the valve box 13A. The valve is constituted of only mechanical elements, when a leakage occurs on the fluid transporting pipe, the fluid in the transporting pipe can be reliably released to the outside. |
