The pressure die (slide piece) serves the purpose of receiving the radial stress, which is generated during the forming process, and supports the straight tube end from outside.

The rotation of both tools around the bending axis bends the tube to the radius of the bend die. When rotary draw bending is applied, the tube is fastened between the bend die and the clamp die. The more common procedures are rotary draw bending, 3-roll bending, compression bending and ram bending (press bending) (Figure 1). Various methods are used for bending tubes depending on the material in use and the required precision. This process works on metal, alloy, aluminum, titanium, and steel. for Cr-Mo and C-Mo-V steels, a subsequent stress relieving heat treatment in accordance with Tab 1 is required.ī) After hot bending performed outside the temperature range specified in, a subsequent new heat treatment in accordance with Tab 22 is required for all grades.Tube bending is a process used to reshape tubing or piping into a certain shape or design.for C, C-Mn and C-Mo steels, no subsequent heat treatment is required,.3 times the external diameter for cold bent steel pipesĪ) The pipes are to be bent in such a way that, in each transverse section, the difference between the maximum and minimum diameters after bending does not exceed 10% of the mean diameter higher values, but not exceeding 15%, may be allowed in the case of pipes which are not subjected in service to appreciable bending stresses due to thermal expansion or contraction.ī) The bending is to be such that the depth of the corrugations is as small as possible and does not exceed 5% of their length.Ī) In the case of hot bending, all arrangements are to be made to permit careful checking of the metal temperature and to prevent rapid cooling, especially for alloy steels.ī) Hot bending is to be generally carried out in the temperature range 850☌ – 1000☌ for all steel grades however, a decreased temperature down to 750☌ may be accepted during the forming process.Ĭopper and copper alloy pipes are to be suitably annealed after cold bending if their external diameter exceeds 50 mm.Ī) After hot bending carried out within the temperature range specified in, the following applies:.

twice the external diameter for copper and copper alloy pipes,.Unless otherwise justified, the bending radius measured on the centerline of the pipe is not to be less than: The bending process is to be such as not to have a detrimental influence on the characteristics of the materials or

Copper tube bending radius chart