Method for shortening replacement time of tool of half-steel-wire off-road radial tyre building machine

The invention relates to a method for shortening replacement time of a tool of a half-steel-wire off-road radial tyre building machine, belonging to the technical field of tyre production. The method is characterized in that a locking piece capsule is mounted on a locking piece; an annular groove matched with the locking piece capsule is formed in the surface of the locking piece; another annular groove is formed in the contact part of the locking piece capsule and a tyre ring of a tyre blank; the width a of the cross section of one of the annular grooves is invariable, and the width b of the cross section of the other annular groove can be designed into several matching widths according to the width of the tyre ring; when tyres with same diameters of the tyre ring mouths and different widths of the tyre rings are built, the matching locking piece capsule only needs to be replaced according to the width of the tyre ring. According to the method, the whole set of locking piece does not need to be replaced or the tyre is replaced into an assembly drum, so that the tool replacement time of the half-steel-wire off-road radial tyre building machine can be shortened, and the production efficiency is improved.