GPT Tools & Equipment Operation 2 — Questions and Answers
Question 1: Which tool is used to cut steel gas pipe to a precise length in the field?
- Reciprocating saw
- Pipe cutter (wheel-type) (Correct answer)
- Angle grinder with abrasive disc
- Hacksaw with coarse blade
Correct answer: Pipe cutter (wheel-type)
A wheel-type pipe cutter produces a clean, square cut on steel pipe and leaves no metal filings inside the pipe.
Question 2: When threading steel gas pipe, what is the correct order of operations?
- Cut, ream, thread, apply dope (Correct answer)
- Thread, cut, ream, apply dope
- Ream, cut, thread, apply dope
- Cut, thread, ream, apply dope
Correct answer: Cut, ream, thread, apply dope
Cutting first establishes pipe length, reaming removes the internal burr, threading creates the fitting connection, and pipe dope seals the joint.
Question 3: What is the primary purpose of a pipe reamer in gas piping work?
- Enlarging pipe diameter to the next nominal size
- Removing the internal burr left by pipe cutting (Correct answer)
- Cleaning rust from the interior of old pipe
- Checking roundness of the pipe end
Correct answer: Removing the internal burr left by pipe cutting
The internal burr left after cutting reduces flow area and can trap debris, so reaming restores the full bore before threading.
Question 4: A pipe die set is labeled '3/4 NPT.' What does NPT stand for?
- National Pipe Thread (Correct answer)
- Normal Pressure Taper
- National Pressure Tubing
- Nominal Pipe Taper
Correct answer: National Pipe Thread
NPT (National Pipe Thread) is the US standard for tapered pipe threads used on gas piping joints to create a pressure-tight seal.
Question 5: Which type of wrench is BEST suited for tightening a large-diameter steel gas pipe fitting in a tight space?
- Chain pipe wrench
- Strap wrench
- Offset pipe wrench (Correct answer)
- Crescent adjustable wrench
Correct answer: Offset pipe wrench
An offset pipe wrench has its jaws angled from the handle, allowing the technician to grip and turn pipe in confined areas where a straight wrench won't fit.
Question 6: What hazard is associated with using an electric drill near a gas leak during repair work?
- Magnetic field interference with gas detectors
- Risk of ignition from motor brushes sparking (Correct answer)
- Excessive vibration causing pipe joint failure
- Ground fault causing regulator malfunction
Correct answer: Risk of ignition from motor brushes sparking
Electric drill motor brushes generate sparks that can ignite an explosive gas-air mixture, so only intrinsically safe or air-powered tools should be used in leak areas.
Question 7: When using a pipe vise to hold gas pipe for threading, where should the vise be positioned relative to the die head?
- At least 6 feet away for safety clearance
- As close as practical to the cut end being threaded (Correct answer)
- At the exact midpoint of the pipe length
- Directly behind the operator for counter-torque
Correct answer: As close as practical to the cut end being threaded
The vise should grip the pipe close to the threading point to minimize flex and vibration, producing cleaner, better-formed threads.
GPT Tools & Equipment Operation 2
Which tool is used to cut steel gas pipe to a precise length in the field?