Abstract: A borehole closure includes a supply line made of plastic and having formed therein a longitudinal passage between a feed end for inlet of an impregnating fluid and a discharge end. The supply line is formed with transverse passages, each covered by a sealing ring. A non-return valve is provided to block a flow of impregnating fluid in the direction toward the feed end. The supply line is sealingly surrounded by an inflating tube to define an elongate annular chamber therebetween which is in communication with the transverse passages. A rupture assembly having a rupture disk is secured at an end surface of the discharge end of the supply line and constructed to burst when a pressure applied by the impregnating fluid exceeds a predetermined value.

Abstract: The borehole closure (1) includes a supply line (2), which is made of plastic and includes a longitudinal passage, and an inflating tube (28). The supply line (2) has a feed end (3) with an external thread (4) and a discharge end (5) with an external thread (6) as well as an integrated non-return valve (18). The inflating tube (28) surrounds the supply line (2) in a sealing manner with its end portions (29, 30) at formation of an elongate annular chamber (33). Transverse passages (37) are provided in the wall (36) of the supply line (2) at the end of the annular chamber (33). The ports of the transverse channels (37) into the annular chamber (33) are covered by elastic sealing rings (39), which are guided through fixing rings (40), arranged on both sides of the sealing rings (39). A rupture disk (25) is fixed to the end surface of the discharge end (5) of the supply line (2) by means of a thrust ring (24) with an internal shearing edge as well as a threaded sleeve (7) with an internal radial shoulder (9).