Pipe branch fitting

Claim 1

In combination, a pipe, an embracement member having a cylindrical inner surface in embracement around the pipe at a point where the pipe has a pre-cut hole, an upstanding, hollow, internally threaded boss on one side of the member, a resilient sealing gasket at the inner side of the boss, a fitting part threaded in the opening having a planar annular surface bearing rotatably on the gasket and being formed at its inner end with a reduced width spigot portion positioned in the pre-cut hole and at its outer end with a nut extending above the boss so that the fitting part can be turned by a wrench to displace the fitting part inwardly to compress the gasket against the pipe, the spacing between the nut and the upper end of the boss serving to indicate visually the extent of inward movement of the fitting part, and an inward-facing shoulder on the spigot end portion for abutment on the outer surface of the pipe within said gasket whereby the compression applied to the gasket is restricted to a predetermined limit, the spigot end portion extending a short distance beyond said inward-facing shoulder, the gasket having at least one annular upper surface portion lying in a single transverse plane and a saddle-shaped lower surface conforming to the surface of the pipe around the pre-cut hole and being confined between and in substantially complete conformity with the adjacent surfaces of the fitting part, the embracement member and the pipe.