APPARATUS FOR TESTING FLUID PRESSURE EQUIPMENT

摘要

1294683 Testing pressure vessels and pipes WESTINGHOUSE BRAKE & SIGNAL CORP 8 April 1970 [30 April 1969] 22049/69 Heading G1S A vessel or brake pipe 1 of an air brake system is connected as shown to a reservoir 9 via a check valve 4 and to a valve 5 having a seat 6 controlled by a piston 51. A gauge 10 is provided and also an exhaust choke 8. In operation air from pipe 1 acts on one side of the piston 51 and also passes through valve 4 to charge the reservoir 9 to the pressure in the pipe 1 less the check valve loading. This reduced pressure acts on the other side of piston 51. Any leak in 1 will cause the pressure to fall so that the pressure on the one side of the piston 51 will fall whilst the pressure in the reservoir 9 and on the other side of the piston will not fall because of the valve 4. The valve 6 is thus caused to open and allows 9 to vent through pipe 61 and choke 8, the pressure difference across the choke being shown on gauge 10. Eventually the pressure in 9 falls so much that the piston may be caused to close the valve 6 again and a state of equilibrium will be obtained in which the venting of 9 reduces the force on the other side of 51 at the same rate as the leakage from 1 reduces the force on the one side of 51 while the valve 6 is not fully closed. The air continuously vented from 9 will produce a steady pressure differential across 8 and thus will be registered on 10 as lb/sq.in/min and related to the leakage from pipe 1. The apparatus may be used for continuous monitoring by re-charging 9 at intervals; or modifications may be made to enable the apparatus to be used on vacuum systems.