Not easy to bend steel pipe or commercially available global file processing methods and not the earth

摘要

A polyethylene or a zinc layer(7,8) is coated on the surface of a PC steel cable(6). Both edges of the coated portion are peeled with some length(l). A cylindrical alloy steel(9) is inserted to the peeled portion and the edge of the coated portion. It is fixed on the cable and the coated portion by rolling or forging. A waterproof cock(12) is inserted to the extended portion of (9). And a waterproof cover is fixed on the connecting portion by pressing. A spiral(10) is made on the alloy steel surface by using a bite.