4130 Precision Tubing
Precision tubing is tube made to closer limits than the general standard requires. For 4130 it means cold drawn seamless tube with tighter control of diameter, bore or wall for parts that must fit, slide or run true.
What 'Precision' Means in Specification
There is no single universal definition of 'precision tubing'. When a buyer specifies 'precision 4130 tubing', they should provide the specific dimensional tolerances required, not just the label. Precision tubing procurement typically specifies:
- OD tolerance (e.g., ±0.001" rather than standard percentage tolerance)
- Wall tolerance (e.g., ±5% rather than standard ±10%)
- Eccentricity (maximum allowed wall-thickness variation around the circumference)
Without explicit tolerance requirements, the supplier cannot determine whether standard CDS tolerances suffice or whether an additional drawing pass is required.
Applications for Precision 4130 Tube
Precision 4130 is used in applications including: instrumentation tube where the bore must accept a defined fitting consistently; hydraulic lines where OD-to-fitting fit is critical; and precision machined components where the tube is used as machining stock and the starting OD tolerance directly affects machining allowance and finished-dimension accuracy.
| Precision Parameter | What to Specify |
|---|---|
| OD tolerance | e.g., ±0.001" or ±0.003" per foot |
| Wall tolerance | e.g., ±5% or tighter — state explicitly |
| Eccentricity | Maximum wall variation — state if required |
| Surface finish | Ra value if critical for sealing or fitting |
| Standard | ASTM A519 CDS or specific precision specification |
Specifying a Precision Requirement
Be specific about what needs to be precise. State the dimension, its tolerance and the reason, for example an outside diameter to suit a bearing, or a bore to accept a sliding tube. A supplier can then tell you whether standard cold drawn tube already meets it or whether special drawing is needed.
Other characteristics can also be controlled: straightness per unit length, ovality, surface roughness of the bore, and wall uniformity. Each tighter limit adds cost, so ask only for what the part needs. For sliding and telescoping fits, remember that both tubes have tolerances, and the clearance you want must survive the worst combination. If the requirement is a custom size as well as a close tolerance, see custom dimension tubing. Geometric terms are explained under 4130 round tubing.
Frequently Asked Questions
Is standard ASTM A519 CDS considered precision tubing?
Standard CDS 4130 per ASTM A519 has defined tolerance classes that are tighter than HFS but not as tight as the most demanding precision applications. For many structural applications, standard CDS tolerances are sufficient. For instrumentation and tight-fit assemblies, verify the specific tolerance required.
What tolerances can be tightened on 4130 tube?
Outside diameter, inside diameter or wall, along with straightness and ovality, within what cold drawing can achieve.
Does precision tubing cost more?
Yes. Closer limits require more controlled production and more inspection.
Is precision tubing always cold drawn?
Yes. Close tolerances and a smooth surface come from cold finishing.
Enquire for Precision 4130 Tubing
State your required OD, wall, and specific tolerance requirements to receive a precision tubing quotation.
- OD & Wall
- OD tolerance required
- Wall tolerance required
- Eccentricity limit (if applicable)
- Standard
- Footage
- MTC
- Delivery