Safety device for installation in a gas-supply system, in particular, an acetylene-supply system

摘要

Relevant specifications in the field of gas supply provide for different safety devices for installation in a gas-supply system, in particular, an acetylene-supply system. To provide such a safety device, which is characterized by a compact structure and a high level of operational reliability, this invention proposes that a valve body (1) incorporates an over-pressure valve (4; 104) of a quick-action shut-off device, a control valve (3; 103) of a pressure-limiting device, and a safety valve (2; 102), whereby the safety valve (2; 102) can be fluidically connected to the over-pressure valve (4; 104) and the control valve (3; 103), and closes either when the over-pressure valve (4; 104) opens due to an inlet pressure that is above the inlet-pressure limit value or when the control valve (3; 103) opens due to an outlet pressure that is above an outlet-pressure limit value.

主权项

1. A safety device for installation in a gas-supply system, where a main pressure regulator relieves regulates an inlet pressure of a gas fed thereto to an outlet pressure, said safety device comprising:
a valve body to which the gas is fed at the inlet pressure and from which the gas is fed at the outlet pressure; an over-pressure valve of a quick-action shut-off device, said over-pressure valve being configured to open responsive to the inlet pressure being above a predetermined inlet-pressure limit value; a control valve of a pressure-limiting device, said control valve being configured to open responsive to the outlet pressure being above a predetermined outlet-pressure limit value, and a safety valve fluidically connected to the over-pressure valve and the control valve; and wherein the safety valve closes either when the over-pressure valve opens due to the inlet pressure being at an inlet pressure level that is above the inlet-pressure limit value, or when the control valve opens due to the outlet pressure being at an outlet pressure level that is above an outlet-pressure limit value; wherein the safety valve has an inlet-pressure gas inlet, an inlet-pressure gas outlet, and a safety-valve chamber therebetween; said chamber being configured to be closed via a safety-valve closing element that is supported so as to be movable inside the chamber in an axial direction and such that the safety-valve closing element moves such that the safety valve opens with the inlet pressure; said chamber being divided into a front pressure chamber and a rear pressure chamber: wherein the safety-valve closing element protrudes into the front pressure chamber facing the inlet-pressure gas inlet with a first effective cross-section; wherein the safety-valve closing element protrudes into the rear pressure chamber facing the inlet-pressure gas outlet with a second effective cross-section that is larger than the first effective cross section, and the rear pressure chamber and the front pressure chamber are both configured to be fluidically connected to the over-pressure valve and the control valve via pressure-compensation lines; wherein the safety-valve closing element is a safety-valve piston; wherein the safety-valve piston has a piston wall sealed off from the safety-valve chamber; and wherein the safety-valve piston has a cavity with at least one cross hole that extends through the piston wall and into an area that is connected to the front pressure chamber when the safety valve is open and that is sealed off from the front pressure chamber when the safety valve is closed.