Independent engineering handbook
ASTM A513 mechanical tubing, explained
A practical, source-conscious reference for selecting, comparing, calculating, and ordering electric-resistance-welded carbon and alloy steel mechanical tubing.
Types 1–6
Match manufacturing route to part requirements.
Dimensions
Control the characteristics that drive fit and function.
Weight tools
Estimate theoretical material mass transparently.
Order clarity
Translate design intent into reviewable purchasing text.
Comparisons
Separate mechanical, structural, welded, and seamless scopes.
Official source
Use ASTM A513/A513M-25 for normative requirements.
Seven quick reference lanes
| Lane | Selection cue |
|---|---|
| Type 1 · Hot-rolled ERW | As-welded route; verify surface, weld treatment, and dimensions. |
| Type 2 · Cold-rolled ERW | As-welded route; verify surface, weld treatment, and dimensions. |
| Type 3 · Cold-worked | Confirm process, availability, and producer capability. |
| Type 4 · Cold-worked | Confirm process, availability, and producer capability. |
| Type 5 · DOM | Welded tube subsequently drawn over a mandrel; not seamless. |
| Type 6 · Sink drawn | Cold drawn without an internal mandrel during the draw. |
| Shapes · Round and formed | Confirm process, availability, and producer capability. |
Manufacturing system
From the purchase specification to the finished tube
Follow requirements, material identity, process evidence, inspection, and release records through the product lifecycle.
- 01Purchase specification
- 02Coil & identity
- 03Forming
- 04ERW seam
- 05Cooling & sizing
- 06Cut & inspect
- 07Documentation
The short answer
ASTM A513/A513M is the ordering specification for electric-resistance-welded (ERW) carbon and alloy steel mechanical tubing. If your tube will be machined, formed, press-fit, or assembled into a mechanical component — rather than designed as a load-rated structural member — A513 is usually the specification conversation to have.
The single most consequential choice inside A513 is the manufacturing type (Types 1 through 6), because the type communicates the production route, and the production route drives dimensional behavior, surface condition, weld-zone character, and cost.
What A513 covers
ASTM A513/A513M covers electric-resistance-welded carbon and alloy steel mechanical tubing. It is an ordering specification: the correct type, grade, condition, dimensions, tolerances, and supplementary requirements must be communicated to the producer.
This guide interprets the decision process without reproducing controlled tables. The purchased standard, drawing, and supplier agreement govern acceptance.
Mechanical tubing differs from structural tubing (such as ASTM A500), pressure tubing, and line pipe in intent, qualification, and typical acceptance criteria. Selecting by nominal size alone — without confirming the governing specification — is one of the most common purchasing errors this publication exists to prevent.
- Mechanical applications rather than structural design qualification
- Round, square, rectangular, and special shapes may be available
- Manufacturing type materially affects finish, dimensional behavior, and cost
Start with process, not a nickname
Terms such as ERW, DOM, HREW, and CREW are useful shop shorthand, but they do not replace the ASTM type designation. Select the type by the manufacturing route and the performance your part actually needs.
A nickname on a purchase order invites the producer to interpret. A type designation, with condition and explicit dimensional requirements, makes the order self-describing and auditable.
- Use Type 1 or Type 2 pages to understand as-welded routes
- Use Type 5 for drawn-over-mandrel dimensional control
- Use Type 6 for sink-drawn tubing where the specified route fits
A complete order prevents assumptions
Identify the standard edition, type, grade or chemistry designation, condition, shape, dimensions, length, quantity, required tolerances, testing, certification, and end-use constraints. Resolve conflicts between the PO and drawing before release.
The specification builder on this site produces a structured ordering description you can reconcile against the official standard and your supplier's quotation before committing an order.
How to use this handbook
Start at the types overview if you are selecting a route. Use the comparison pages when weighing A513 against A500 or A519, or when translating shop terms like DOM and HREW into specification language. Use the calculator for theoretical weight and the manufacturing section to understand how ERW tube mills produce, inspect, and troubleshoot this product.