Patent ID: 9644797
Date: 2017-05-09
CPC Classifications: A62C,F16L,F17D,Y10T

Claim:
1. A vacuum pumping arrangement comprising: a vacuum pump having an inlet; and an apparatus connected to the inlet of the vacuum pump for inhibiting the propagation of a flame front ignited by a pumping mechanism drawing a waste stream from a process chamber, the apparatus comprising: a foreline for conveying the waste stream drawn from the process chamber to the pumping mechanism, the foreline comprising an isolation valve for selectively isolating the pumping mechanism from the process chamber and a bypass around the isolation valve; and a controller for actuating the isolation valve, wherein the controller is configured to: cause the isolation valve to be closed when the waste stream is initially drawn from the process chamber so that the waste stream is conveyed to the pumping mechanism via the bypass, the bypass comprising means for inhibiting propagation of a flame front therethrough; and cause the isolation valve to be opened when a pressure within a region upstream of the isolation valve has been reduced below a value at which propagation of a flame front within the waste stream can be sustained.