| 摘要 |
The present invention relates to a gas supply system situated between a gas take-off point, such as a gas meter (27), provided in a building (2), and a gas pipe (1) accommodated underground (3), comprising a branch pipe piece (9) connected to the gas pipe, a connection pipe piece (10) fed into the building, and a pressure-relief valve (20) which is in an open position in the at-rest state and which can be brought to the closed position when a predetermined nominal flow intensity and/or a predetermined nominal pressure difference across the pressure-relief valve is exceeded. The invention also provides an emergency device (26) which has suction means (29-32) for generating an underpressure in the gas pipe section between the gas take-off point (27) and the pressure-relief valve (20), and sensor means (36) for activating the suction means. Said suction means (29-32) are able to generate an underpressure of a magnitude such that the resultant flow intensity and/or the resultant pressure difference across the pressure-relief valve (20) is greater than the predetermined nominal flow intensity and/or the predetermined nominal pressure difference across the pressure-relief valve and such that the pressure-relief valve closes under the influence of said flow intensity and/or said pressure difference. |
