Standard and specialty tubing is available in a variety of alloys to meet your specific applications. Stainless steel alloy, high temperature alloys, corrosion resistant alloys and nickel alloys. Most alloys are available as seamless or welded and drawn tubing.

Size Limits and Tolerances
Tube Methods’ sizes range from 0.030” to 1.250” outside diameter (OD) and 0.003” to 0.280” wall. The table (see reverse) provides standard sizes and tolerances. Please consult the Sales Department if closer or different tolerances are required.

Tolerances

• OD tolerances are measured using micrometers. Laser micrometers are used for thin walls or extra close tolerances. Ovality will be within the OD tolerance for tubes where the wall thickness is at least 3% of the nominal OD.
• ID tolerances require special definition because of different interpretations. Three methods of inspection are described here.
  

Eccentricity: The difference between the center of the circle formed by the tube OD and the center of the circle formed by the tube ID. Commercial tolerance for eccentricity is +/-10% of average wall thickness (20% TIR).
- Closer tolerances can be supplied if required.

Straightness: Commercial straightness is 0.010" per foot of length; that is, a tube 10 feet long will be straight within 0.100."
- Closer tolerances can be supplied if required.

Length Tolerance:
- Random Lengths: +/-3.5 feet.
- Cut Lenghts: Up to and including 1 foot: +/- 0.010"; over 1 foot tolerances: +0.125" -0.
- Closer tolerances can be supplied if required.

Shape Tube Tolerances: Major axis +/-0.005"; minor axis +/-0.003."
- Closer tolerances can be supplied if required.

Surface Roughness: Special OD and ID surfaces are available.
- Contact our Sales Department with specific requirements.

Tempers:
- Annealed is standard but 1/8, 1/2 and full hard are also available.
- Customer specified hardnesses and tempers are also available.

Definitions

Go/No-Go Plug Gauge: The Go Plug will go into the ID of the tube. The No-Go Plug will not start. For example..0.250” +0/-0.004” ID tube, a 0.246” plug will go into the ID of each tube. A 0.250” plug will not start. Note that a 0.250” plug will not fit into a 0.250” hole. This is the standard method for inspecting tubing and will be used unless otherwise specified at time of inquiry.

Go Thru/No-Go Through Plug Gauge: The Go Plug will pass freely through the entire length of the tube. The No-Go Plug may start but will not go freely into the ID for the length of the plug.

ID Micrometer : When size permits, tubes may be measured with an ID micrometer. Results may be different than those measured with plug gauges. Also ID micrometers may be “three-point” micrometers that will measure average ID or “two-point” which will measure the high and low values.


Alloys