Page 154 - CITS - Fitter Trade Practical - Volume -2

FITTER - CITS

EXERCISE 86 - 88 : Threading G.I pipes using die
stocks

Objectives

At the end of this exercise you shall be able to
• cut threads on G.I.pipe using die stock.

Select a set of dies, and ratchet-type die stock. (Fig 1& 2).

Open the adjustment lever. (A)

Coincide the zero setting mark ‘0’ die stock and then insert the four dies according to the number on the dies and
die stock respectively.
Ensure that the dies sit in the correct position.

Be sure that the number on the top edge of the die corresponds with the number of the slot into
which it is to be placed.
Fix the pipe in a pipe vice and tighten to prevent it from rotating. (Fig 3)

Ensure that the projection of the pipe is within 150-250 mm from the vice.

Open the self-centering pipe guide and slide the stock over the end of the pipe.
Adjust the pipe guide for correct sliding, fit and lock into position (Fig 4)
Apply a cutting lubricant to the part which is to be threaded.

Use lard oil, or mineral-lard oil when threading G.I.pipes.
Apply a little pressure to the stock and keep the handle at right angle to the pipe axis.

139