Precision Stainless
Instrumentation Tubing
SEAMLESS & WELDED • TP304/L & TP316/L
Bright Annealed (BA) tubing engineered for leak-free connections with compression fittings. Strict tolerance control for hydraulic and instrumentation lines.
Seamless or Welded?
ASTM A269 covers both manufacturing methods. Choosing the right one depends on your pressure requirements and budget.
Seamless (SMLS)
Extruded from a solid billet. No longitudinal weld seam means consistent strength around the entire circumference. The preferred choice for high-pressure and critical safety applications.
Welded (WLD)
Formed from strip and longitudinally welded. Our A269 welded tubing is bead-worked or cold-drawn, making the seam almost invisible. Offers superior wall thickness consistency (concentricity).
Surface Finishes
Engineered for Purity
The internal surface condition of tubing is critical for instrumentation lines to prevent contaminant entrapment and ensure smooth flow. We offer two finish options.
Annealed & Pickled (AP)
Bright Annealed (BA)
Tested for Reliability
Instrumentation lines cannot fail. Every lot of our A269 tubing undergoes rigorous destructive and non-destructive testing.
Hardness Control
Soft tubing is essential for leak-free compression fittings (ferrule bite). We restrict hardness to ensure it is softer than the fitting material.
Flaring Test
A section of tube is expanded on a tapered mandrel. This verifies the steel's ductility and ensures no cracking occurs during flare fitting installation.
Non-Destructive Test (NDT)
100% Eddy Current testing or Hydrostatic testing is performed to detect any invisible sub-surface defects or pinholes along the entire length.
Flattening Test
Validates the strength of the weld seam (for welded tubing) and overall structural integrity. The tube is flattened between parallel plates without splitting.
A269 vs. A213 vs. A249
Confusion is common. Here is the definitive guide to choosing the right specification for your project.
| Feature | ASTM A269 (Our Focus) | ASTM A213 | ASTM A249 |
|---|---|---|---|
| Primary Application | General Service & Instrumentation Hydraulics, Gas Lines |
Boilers & Heat Exchangers High Temp Service |
Boilers & Heat Exchangers Heat Recovery |
| Manufacturing | Seamless or Welded | Seamless Only | Welded Only |
| Wall Tolerance | Typically Average Wall | Strictly Minimum Wall | Average Wall |
| Tensile Testing | Not mandatory (Historically) *Though typically performed |
Mandatory | Mandatory |
| Hardness Limit | Max 90 HRB (Crucial for fittings) | Max 90 HRB | Max 90 HRB |
Pro Tip: Dual Certification
Most of our seamless tubing inventory is Dual Stenciled as ASTM A269 / A213. This means you get the best of both worlds: the strict testing of A213 and the instrumentation compatibility of A269.
Dimensional Availability
We stock a comprehensive range of seamless and welded tubing in both Imperial and Metric sizes.
Imperial (Inch)
- Common ODs 1/8", 1/4", 3/8", 1/2", 3/4", 1"
- Large ODs 1-1/2", 2", 3", 4"
- Wall Thickness 0.020" to 0.120"
- Gauge (BWG) 16 BWG - 22 BWG
Metric (mm)
- Small ODs 3mm, 6mm, 8mm, 10mm, 12mm
- Large ODs 16mm, 20mm, 25mm ... 80mm
- Wall Thickness 0.5mm to 3.0mm
- Standard EN 10216-5 / ISO 1127
Technical FAQ
Answers to common engineering questions regarding specification, hardness, and compatibility.
Is your A269 tubing compatible with Swagelok® or Parker® fittings?
Yes, absolutely. The key requirement for compression fittings is that the tubing must be softer than the fitting ferrules to allow for a proper "bite" and seal. We strictly control our annealing process to ensure a maximum hardness of 90 HRB (typically 80 HRB), making it perfectly suitable for standard instrumentation fittings.
What is the working pressure rating of A269 tubing?
ASTM A269 itself does not specify pressure ratings; it specifies dimensions and testing. The working pressure depends on the OD, Wall Thickness, and Material Grade. Seamless tubing generally offers higher pressure ratings than welded equivalents. Please contact us for a detailed pressure chart based on your specific size.
Can I use A269 tubing if my spec calls for A213?
Often, yes. ASTM A213 is primarily for boilers and heat exchangers and has stricter "Minimum Wall" requirements. However, much of our seamless inventory is Dual Certified (A269 / A213). Check the Material Test Reports (MTRs) provided with your quote to confirm compliance with both specs.
Does A269 require tensile testing?
Historically, ASTM A269 did not strictly mandate tensile testing for all sizes, focusing instead on flaring and hardness. However, to ensure premium quality, we perform tensile tests on our lots to verify they meet the mechanical properties typical of 304/316 grades (min Yield 30ksi, min Tensile 75ksi).