The Pipe Diameter Tape Measure That’s the Black Sheep of the Family

The pipe diameter tape measure that is frequently overlooked, has more to offer than all the others.

This forgotten child gives you the outside diameter of a pipeline in both inches

The Black Sheep of Pipe Diameter Tape Measures
The Black Sheep of Pipe Diameter Tape Measures

and centimeters. It is valuable to both Americans (using the inch system) and those who use the Metric system of measurements. It goes up to 38″ diameter (955 millimeters diameter). The only thing it doesn’t offer is the ability to measure straight objects. You would have to have a regular tape for that.

Who would use this tape? Inspectors who travel and deal with both systems. Any drilling companies that use both metric and imperial systems of measurement.

Pi-Cobra Diameter Tape, Metric & Inch Pi-Cobra Diameter Tape, Metric & Inch

Who Makes Diameter Tape Measures?

Lufkin Pipe Diameter Measuring Tape
Lufkin Pipe Diameter Measuring Tape

There are 4 main manufacturers of diameter tape measures.

  1. Lufkin® has a world-wide reputation for making high quality tape measures. They used to make them in the USA, but they have shifted the production facilities to Mexico. Some of the tapes are made out of a cast case, which is highly polished and chrome plated, like the w906pd. Others, like the w606pd have a stamped case, which is shiny and chrome plated.  A third type of case is black plastic, like the asw616pd. However, the tape blade inside is the same in all 3 types of cases. It is capable of measuring diameters up to 23 inches.
  2. Pi-Cobra is a brand name for diameter tapes made with

    Pi-Cobra Diameter Tape, Metric Pi-Cobra Diameter Tape, Metric

    a cast case which is chrome plated. It can hold a longer tape blade, capable of measuring diameters up to 38 inches. The case is very durable. These are manufactured in China.

  3. 24inch-od-tape

    Various other Chinese manufacturers make versatile OD tapes like the 416-04-024-P. The back side of the tape measures diameter up to 24″ in 100ths of an inch or 610 mm. The case is plastic, and has a key ring attached to it.

  4. The UT-56675 is made in the USA. It is capable of
    diameter-tapes-com UT-56675

    measuring pipes up to 45 inches in diameter. This is a belt tape, not a pocket tape. The calibrations are in tenths of an inch diameter.


5 Pipe Diameter Tape Measure Tips

When you use your Lufkin or Pi-Cobra pipe diameter tape measure, here are 5 tips to keep you out of trouble.

How to Measure the Diameter of a Pipe
How to Measure the Diameter of a Pipe
  1. Make sure the pipe is free of dirt and mud. You don’t want to measure those things, just the pipe.
  2. Use the right tape. Do you want your answer in 100ths of an inch, 64ths of an inch, or millimeters? There is a tape for each purpose.
  3. Use the right side of the tape. The other side is probably a regular linear tape. It will give you the circumference, not the diameter.
  4. Wrap the tape around the pipe straight, not at an angle. If it is not straight, you will get an elevated result. You can test this by wiggling the tape so that it gives you the lowest reading.
  5. Be familiar with the scale. It can be tricky on a 64ths of an inch diameter tape. 48 on the scale means 3/4 ” diameter. The easy one is 32, which is of course 1/2″ diameter.

How To Choose The Correct Pipe Diameter Tape Measure

Diameter Tapes
Diameter Tapes

Answer these questions for yourself, and you will get the right pipe diameter tape measure!

  1. Metric or Imperial (Inch). Which do you need in your job? There are also 2 tapes that have BOTH metric and inch diameter scales. If the SKU number has a “m” in it, that means it is a metric scale.

    Pi-Cobra Diameter Tape, Metric & Inch Pi-Cobra Diameter Tape, Metric & Inch

    24inch-od-tape3.jpg 24″ OD Tape Measure, Metric & Inch

  2. 64ths or 100ths? This question applies only if you need the Inch version of a pipe diameter tape. If you are in the oil and gas industry, you probably prefer the 100ths calibration. If you are in the boat or automotive industries in the USA, you would probably prefer the 64ths of an inch calibration. If the SKU number has a “d” in it, this means it is calibrated in 100ths of an inch.
  3. Size. The Lufkin models of the pocket diameter tapes will measure pipe diameters up to 23 inches. The Pi-Cobra models will measure pipe diameters up to 38 inches.

    Lufkin Y906PD pipe diameter tape measure, not Barlow W906PD Lufkin Diameter Tape

    Pi-Cobra Diameter Tape, Inches Pi-Cobra Diameter Tape, Inches