Conduits used in electrical installations shall possess adequate mechanical strength. One of the tests used for ascertaining the mechanical strength of conduits is the bending test.
The Bending Device For Rigid Non-Metallic Conduits consists of a base plate fitted with a pin on which interchangeable formers of specified sizes can be kept. A screw-operated clamp holds the test specimen in position against the former.
Two manually operated levers having their pivot points at the centre of the former holding pin are provided for bending the conduit. The bending rollers are in form of metallic cylinders of the required shape and size and mounted on ball bearings to give a smooth movement. The central axis of the bending rollers is adjusted for conduits of different diameters by holding them at different locations on the levers.
IS 9537 (Part 3) - 1983 : Specification for Conduits for Electrical Installations
Part 3 : Rigid Plain Conduits of Insulating Materials