Abstract: Method of producing tube bends of a given diameter and substantially uniform wall thickness from a straight tube having a diameter smaller than the given diameter, which includes re-shaping at least one end of the straight tube with a work-tool to form tangentially directed cylindrical leg extensions of equal tube bend cross section.

Abstract: A machine for the trimming of a pipe bend held in a die in a machine frame has two hydraulic rams mounted at 45.degree., the piston rod of each ram carrying one of a pair of rotary cutting devices for trimming respective ends of the pipe bend. Under the two hydraulic rams there are arranged, each on a respective inclined guide way and likewise at an angle of 45.degree. in the machine frame, movable swarf or burr removing chamfering devices moving to bring their rotary cutter head coaxially into engagement with a respective trimmed end of the pipe bend.

Abstract: The invention provides an improved method and apparatus for pipe bending. In the method a leading portion of a length of pipe is heated and bent around a mandrel into a pipe bend, whereafter it is hot calibrated or sized to finished dimensions and at the same time cut off and trimmed to size at both ends. In a machine for carrying out the method, there are a heating chamber and an interchangeable bending mandrel. At the end of the bending mandrel there is a horizontally functioning calibrating or sizing device. A severing device is both in front of and behind the calibrating device for cutting off and trimming the pipe bend, and the pipe bend is movable both longitudinally and/or transversely in the horizontal plane.

Abstract: A process for finishing a 15.degree. to 180.degree. pipe bend which has been preformed on a pipe bending press comprises submitting a preformed pipe bend at a temperature of 700.degree. to 900.degree. C. at which it leaves a pipe bending press to a hot sizing operation which includes trimming both ends of the pipe bend to precise dimensions to eliminate further finishing.