The pipe bending factory tells you: the degree of deformation of the pipe depends on the relative bending radius R/D and relative thickness t/D. The smaller the R/D and t/D values, the greater the degree of deformation.

In order to ensure the forming quality of the pipe fittings, the degree of deformation must be controlled within the allowable range. The pipe bending forming limit not only depends on the mechanical properties and bending methods of the machining material, but also considers the use requirements of the pipe fittings. The forming limit of pipe fittings should include the following contents:

• 1. The maximum elongation deformation in the tensile deformation zone outside the neutral layer does not exceed the allowable value of the material plasticity and breaks;
• 2. In the pressure-measuring deformation zone in the neutral layer, the thin-walled structure part subjected to tangential compressive stress will not wrinkle beyond the instability;
• 3. If the pipe fitting has the requirement of ellipticity, control its section to produce distortion;
• 4. If the pipe has the strength required to withstand the internal pressure, control the forming limit of its wall thickness reduction