How to Thread Black Pipe

Black pipe is threaded using a threading die

Black steel pipe is usually used in the home for gas supply. The pipe comes in pre-cut sizes and is threaded at both ends. However, when a section of pipe has to be cut with a rotary pipe cutter, the pipe cut has to be threaded. This requires a device called a threading die, which can be bought or rented. Check the diameter of the pipe to get the right size die.

Things You'll Need

• Vise
• Cutting oil and brush
• Threading die
• Old rag

Instructions

1. Place the black pipe securely in a vise to hold it. Smear cutting oil around the end of the pipe with a brush.

2. Fit the threading die over the end of the pipe. Slowly turn the die clockwise for half a turn.

3. Turn the die counter-clockwise a quarter turn to allow metal chips to fall out. Then rotate the die clockwise another half turn, before turning the die counter-clockwise again a quarter turn. Repeat this process until the thread is cut--stop threading the pipe just short of the die's thickness. Remove the die from the pipe--rotate it counter-clockwise.

4. Remove the black pipe from the vise and wipe oil from the thread with an old rag.

Tips & Warnings

• Be careful wiping the oil with the rag, as the threads may be sharp.

References

• Extreme How-To: Working With Steel Pipe