Patent ID: 8540137
Filing Date: 2013-09-24
Classification: B23K,Y10T

Abstract:
1. A water-degradable welding purge dam for purging a weld zone of a pipe assembly comprising first and second pipes having respective first and second ends to be welded together at a root gap, said purge dam comprising: a blocking plate comprising two or more plate members; said two or more plate members including a friction plate member having a plurality of flexible members on its periphery adapted to flexibly engage an inside wall of one of said first or second pipe ends, such that said purge dam is self-retaining in said pipe assembly; said two or more plate members, including said friction plate member and its flexible members, being substantially planar; said two or more plate members including one or more substantially planar support plate members on one or both sides of said friction plate member to laterally support said friction plate member; said one or more support plate members have an outer periphery that is aligned with a base of said flexible members; and said purge dam comprising one or more water degradable materials so that it can be flushed from said pipe assembly following welding.