摘要 |
A strip for the formation of helical pipes by winding said strip into a helical shape. The strip (1) has a narrow, long, flat body, and on one edge of said body, there is a joining rib (3) that is provided continuously in the longitudinal direction of the strip and that is perpendicular with respect to the strip; on the other edge of the body, there is provided a socket (4) into which said joining rib can be inserted. There is a slanting rib (5) that extends to the outside from the lower portion of said socket. When the joining rib is inserted into the socket, the connecting part (51) that connects the socket with the slanting rib and the part connecting with said joining rib of the body of the said strip form a space therebetween in which a soft and elastic packing (7, 8) is provided. |