HVACR116 – Trade Skills

Cutting and Threading Steel Pipe

Work area safety

• Keep your work area clean and well lit - Cluttered areas invite accidents.

• Do not operate tools in explosive atmospheres such as in the presence of flammable liquids, dust or gasses. Tools can create sparks which may ignite the dust or the fumes.

Work Area Safety

• Keep by standers, children and visitors away while operating tools. Distractions can cause accidents and cause you too loose control.

• Do not let visitors operate or touch any tool. People not trained on equipment invite accidents.

Electrical Safety

• Grounded tools must be plugged into an outlet, properly installed and grounded in accordance with all codes and ordinances. Check with a qualified electrician if you are in doubt.

• Never remove the grounding plug or modify the plug in any way. Do not use adapter plugs.

Electrical Safety

• Avoid body contact with grounded surfaces such as pipes, radiators, ranges and refrigerators.

• Do not expose electrical tools to rain or wet conditions.• Do not abuse the cord. Never use cord to carry the tools

or pull the plug from the outlet.

Electrical Safety

• Keep the cord away from heat, oil, sharp edges or moving parts.

• Replace any damaged cords immediately.• When operating a tool outside, use an outdoor extension

cord marked “w-a” or “w”

Electrical Safety

• Connect the tool to an AC power supply that matches the name plate specification.

• Incorrect voltage supply can cause electrical shock or burns.

• Use only three way extension cords which have three prong grounding plugs and three pole receptacles which accept the tools plug.

Electrical Safety

• Use proper extension cords. Insufficient conductor size will cause excessive voltage drop, loss of power and overheating.

• Keep all extension cord connections dry, off the ground and out of puddles.

Personal Safety

• Stay Alert, watch what you are doing and use common sense when operating a tool.

• Do not use tools when under influence of alcohol or medications.

• Dress properly, no loose clothing.

Personal Safety

• Avoid accidental starting. Be sure switch is off before plugging in.

• Do not over-reach. Keep proper footing and balance at all times.

• Use safety equipment. ALWAYS wear eye protection.

• Operate machines from side with the switch.

Specific Safety

• Always consult the tool manufacturers operating manual for specific safety information.

• Injuries from threading machines can be:o Loss of fingers.o Electric Shocko Broken boneso Eye injuries

Threading machine safety

• Machines are made to cut and thread pipe.• Secure machine to bench or stand• Support long heavy pipe with pipe supports• Do not wear loose clothing or loose gloves.

Threading machine safety

• Do not reach across the machine• Do not use machine if foot switch is broken.• Tighten chuck hand wheel and engage rear centering

device on the pipe before turning on the machine.

Threading machine safety

• Lock foot switch when not in use.• The foot switch is for your safety. It lets you shut off the

motor by removing your foot. If clothing should get caught in machine it will continue to pull you in. Because the machine has a high torque the clothing itself can bind around your arm with enough force to break it.

Tools required

• A holding deviceo Chain Viseo Yoke Viseo Motorized pipe vise

• The chain and yoke vise are for hand cutting and threading only.

Tools Required

• The motorized vise is used with mechanical threading. There is a switch with three positions on this vise, Reverse (counter clockwise), OFF, Forward (clockwise).

Tools Required

• Pipe Cutter:o Makes a square cut but there must be room to swing the cutter

aroundo Hacksaw: one with 18 to 24 teeth per inch may be used if proper

pipe cutter is not available or unusable.

Tools Required

Tools Required

• Pipe reamer:o Removes burrs from the inside of the pipe after it has been cut.o The burrs must be removed because they restrict the flow of

fluids or gas.

Tools Required

Tools required

• Pipe Threadero Also known as a die.o Most threaders used in the field are fixed die threaderso Can be used to clean up existing threads.

Tools required

• Oilero Used to supply cutting oil to the pipe as threads are being

cut.o The oil cools the die which extends the tools life.o The oil cools the pipe which prevents jagged and

malformed threads.o Usually comes with an attached tub to catch shavings and

recycle the oil

Tools Required

• Pipe Stando Used to support long pipe lengths extending out from the vise

Tools Required

• Pipe Wrencheso Can be used to attach the fittings to the pipe while in the vise.o Used to assemble piping systems after threading.

Procedures for cutting

• Measure and mark length of pipe being worked.• Insert pipe into vise

o Insert short pipe through front of machineo Insert long pipe through rear of machineo Use support stand if vise can not support pipe safely

Procedures for cutting

• Make certain that pipe is centered in centering device at the read of the machine and tighten.

• Tighten front chuck jaws with a repetitive counter clockwise snap spin of the handwheel. This hammering action tightens the jaws on the pipe. A clockwise rotation snap spin releases the jaws.

Procedures for cutting

• Cuttingo Engage pipe cutter with pipe and align cutter wheel with

mark on pipe.o Rest pipe cutter frame on the support bar located on the

switch side of the machine.o Tighten cutter feed screw handle until snug. Do not over

tighten.o With power cord plugged in turn rev/off/on switch to

FOR(forward) position.

Procedures for cutting

• Place foot on foot switch to operate the machine.• Continuously tighten the feed screw handle with both hands until

the pipe cutoff is complete.• Release foot switch and turn REV/OFF/ON switch to OFF position.

Procedures for Reaming

• Turn REV/OFF/ON switch to FOR position• Insert reamer into the end of the pipe and hold firmly onto

handle and handgrip.• Step on foot switch and push on reamer handgrip with

right hand to ream pipe.

Procedures for Reaming

• Release foot switch, remove reamer and turn REV/OFF/ON switch to OFF position.

Procedures for Threading

• Place threader on end of pipe with handle resting on support bar on switch side.

• Place oiler under threader and apply thread cutting oil to pipe end.

• Turn Rev/OFF/ON switch to FOR (Forward position)

Procedures for Threading

Procedures for Threading

• Step on foot switch and push threader with right hand to engage dies.o Note: Threader is AUTOMATIC once dies are engaged. Apply

plenty of oil until threads are completed.• Release foot switch once threads are completed.• Push back support bar on switch side.

Procedures for Threading

• Reverse threader ratchet knob.• Lower threader handle and pull support bar out. Threader

handle is now against lower side of the support bar.• Turn REV/OFF/ON switch to Rev (Reverse) position and

back off threader by stepping on foot switch.

Procedures for Threading

• Release foot switch and turn REV/OFF/ON switch to OFF position.

• Inspect threads, look for broken or chipped threads. Use a pipe fitting of same size to check threads.

Procedures for Threading

Procedures for Threading