Services
Standard and specialty tubing is available in a variety of alloys to meet your specific applications. We offer stainless steel, high temperature, corrosion resistant, and nickel alloys. Most alloys are available as seamless or welded and drawn tubing.
Size Limits
OD: 0.030” to 1.50”
ID: Down to 0.008″
Wall: 0.002” to 0.280”
Tech Tube’s sizes range from 0.030″ to 1.50″ outside diameter (OD) and 0.002” to 0.280” wall. Inner diameters can be sized down to 0.008″. Metric sizes are available. Please consult our Sales department if different sizes 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 below.
Commonly Requested Tolerances
| Tube OD (inches) | Outside Diameter | Inside Diameter | Wall Thickness |
|---|---|---|---|
| Up to and including 0.2505" | ±0.002" | ±0.002" | ±10% |
| 0.251" through 0.5005" | ±0.003" | ±0.003" | ±10% |
| 0.501" through 0.7505" | ±0.004" | ±0.004" | ±10% |
| 0.751" through 1.250" | ±0.005" | ±0.005" | ±10% |
Custom tolerances are available upon request.
Additional Standards
Eccentricity
Commercial Tolerance: ±10% of average wall thickness (20% TIR)
The difference between the center of the circle formed by the tube OD and the center of the circle formed by the tube ID.
Closer tolerances can be supplied if required.
Straightness
Commercial Straightness: 0.010″ per foot of length
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 Lengths: Up to and including 2 feet: ±0.010″; over 2 feet: ±0.125″
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
Standard: Annealed
Additional Tempers: 1/8 hard, 1/2 hard, full hard, heat treated
Customer specified hardnesses and tempers available as requested.
Shapes
- Round
- Flat Oval
- Elliptical
- Rectangular
- Square
- Custom
Inspection Methods
Unless otherwise requested, Pin Class Z is used throughout all processes.
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, for a 0.250” ±0.004” ID tube, a 0.246” plug will go into the ID of each tube. A 0.254” plug will not start. This is the standard method for inspecting tubing and will be used unless otherwise specified at time of inquiry.
Go Thru/No-Go Thru Plug Gauge
The Go Thru Plug will pass freely through the entire length of the tube. The No-Go Thru 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. Note: ID micrometers may be “three-point” micrometers, which will measure average ID, or “two-point” micrometers, which will measure the high and low values.
ID Air Gauge
Air gauges are used in applications where highly precise measurements are required. A hardened steel probe is inserted into the ID of a tube, where air is pushed through the body of the probe and out small outlet holes. The tube creates a backpressure into the probe, where measurements are recorded. Since the probe does not need to touch the tube to record a measurement, all possible contaminents can be blown away, resulting in a highly precise recording.