PIPE END TREATMENT METHOD

PROBLEM TO BE SOLVED: To obtain the surely sealing effect by providing a temporary seal process to pour the resin inside a piping, a permanent seal process to fit a closing plug inside the piping, an airtightness inspection process of a piping end part, and a piping cutting process to cut an excessive pipe on a road surface. SOLUTION: In a closing plug 10, an elastic seal member 13 is externally inserted in an outer circumferential part of a plug body 12 having a flange part 11 at a distal end part in the insertion direction X adjacent to a flange part 11. A male screw part 14 is formed on an outer circumferential part of the plug body 12. A female screw part 15a of a cylindrical holding nut 15 is screwed thereto. The holding nut 15 is a member to deform the elastic seal member 13. By relatively turning the holding nut 15 to the plug body 12, an end part of the holding nut 15 gives a pressing force to the elastic seal member 13, the elastic seal member 13 is expanded to the diameter Y of a gas pipe 4A and closely attached to an inner circumferential surface of the gas pipe 4A.