Abstract: The system increases the diameter to which pipe flanges can be flared. The tendency of the radial wall of the flange to crumple inwards is obviated by coining the transition corner of the wall. First, the pipe end is belled out to provide access for the coining punch. The belled-out end is then swaged back in, after the punch is removed. With the corner transition thus preconditioned, further axial pressure on the pipe with a suitable female punch causes the flange to expand diametrally in a controllable manner.

Abstract: For use in push-in-and-snap pipe connectors, the region of the pipe behind the integral end-flange is raised in diameter. If the pipe is properly inserted, the raised region is concealed inside the body of the fitting; but if the pipe is not pushed fully home into the body, the raised region is visible, and serves to alert the production-line inspector that the joint is not sealed. A snap-in sping clip holds the pipe in the body, and the clip rests against the raised protion to minimise the chance of vibration noise. The flange and raised region are formed in the pipe by axial-press punches and dies.