Mechanical shaft introducing foreign advanced production equipment andfabrication technology, adopts refined sliding rings with assembly axis, shafthead for the high quality steel products with black, easy to operate, slittingmachine precision. When used, with my company profession configuration of theair gun mouth filling gas, made innerring sliding and roll ball embossing,thereby sliding lock nitrogen-treated barrel, when unloading, holding thedeflated mouth then it can unloaded.