Electronic monitoring of pipe welds - is performed by applying HV along subterranean pipe and measuring fluctuations in voltage either side of weld

摘要

The integrity of welded joints in a buried pipe (2) is monitored by an electrical apparatus. Points on the pipe remote from the welded joint on either side thereof have integral terminals (7) and (8) to which electrical supply lines (5) (6) are connected. a power source (4) applies a charge to the lines (5)(6) causing a high potential difference across the length of pipe (D) spanning the monitored weld (3). Interrogation lines (12)(13) are connected to remote monitor (9) and measure the potential across the smaller length of pipe (d) also spanning the weld (3). Fluctuations in the measured p.d. across the indicate fault conditions therein.