Hello mouldmakingandcasting,
The bending of PE pipe is permissible and the properties of fusion jointed systems enable changes of direction without recourse to the provision of special bends or anchor blocks. However, for PE materials the pipe should not normally be cold bent to a radius less than 25 times the outside diameter of the pipe. In special circumstances and only in the smaller service diameters this requirement may be relaxed to 15 x OD for SDR 11 pipe, provided no joints or tappings occur on the bend and great care is taken not to kink the pipe.
I can confirm our 25mm MDPE pipe is SDR 11 however for safety reasons would recommend a minimum bending radii of 625mm.
Thank you for using Q&A
Answered by: SWake
Date published: 2021-12-11