Page 168 - CITS - Fitter Trade Practical - Volume -2

FITTER - CITS

Job Sequence

Bending G.I. pipes using sand and pegs

Objectives : At the end of this exercise you shall be able to
• bend G.I. pipe by hot method.

File the pipe ends square. (Fig 1)

Remove burrs.
Calculate the length of pipe.(Fig 2)

If D = diameter of bend
Ø = angle of bend
l = length of curved portion
If OA = inner radius of bend (R)

AB = radius of pipe (r)
OB = radius of bend (R+r)
then, l = (R+r) x Q x 0.01745.
Total length of pipe = L + L + l.
1
2
Measure and mark off the:
- centre of the bend (Fig 3)
- beginning and end of the bend from the centre line.
Measure the inside diameter of the pipe and select two suitable wooden pegs for the pipe. (Fig 4)
Plug one end of the pipe with a wooden peg.(Fig 5)

Fill the pipe with clean, dry and fine sand [Compress the sand by tapping the pipe up and down with a soft ham-
mer.] (Fig 6) and plug the end.

153

CITS : C G & M - Fitter - Exercise 86 - 88