Diameter of mandrel for reinforcement to bend it in L shaped and c shaped hooks

Diameter of mandrel for providing L shape - bend and c shape - hook

d is the dia of bar

As per IS 2502 1963

For upto 25 mm dia bars - 8d
Above than 25 mm dia bars - 12d

As per BS 8666 2005

For upto 16 mm dia bars - 4d
Above than 16 mm dia bars - 7d

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