Structural and body members
The tube is usually welded into an assembly, so the governing requirement is the structural standard plus the weldability basis — not a mechanical tubing specification.
Automotive Application
Steel Tubes for Automotive
Automotive part supply is released against the approved component drawing, its revision and the programme's qualification plan. The vehicle system is a context for the order, not an approval of it — naming the application does not select the tube type, the grade or the condition.
No chemistry values, mechanical properties, tolerance figures, pressure ratings or test results are published on this page. Every figure used in a live enquiry comes from the ordered edition of the governing standard and your own programme specification.
Automotive duties
Six tube duties and what each one actually asks for
These paths address different purchasing decisions. The component and its duty decide which family of specifications applies — reading the tube standard first is how a conforming part ends up on the wrong line.
Chassis and suspension tube
Fatigue and impact duty drive the material and fabrication basis. The tube specification follows the programme's own structural requirement.
Exhaust and emissions components
Temperature and corrosion duty set the material family, and the fabrication route is agreed with the tier supplier rather than chosen from a catalogue.
Fluid and fuel lines
A fluid-carrying duty brings its own pressure and cleanliness requirements. Review whether the application is served by a tube standard written for fluid service.
Seat frames and interior structures
Section geometry and weldability usually control. Confirm whether a hollow section or a mechanical tube is the correct family before specifying.
Machined powertrain components
Where the tube becomes a bushing, spacer or sleeve after machining, the machining allowance and final geometry are the controlling decisions.
These are purchasing categories, not material approvals. A structural member, a fluid line and a machined bushing are served by different standards, and the same tube is not correct for all three.
Selection logic
What actually selects the tube on an automotive part
The drawing and the programme specification govern. These five points are the ones most often left implicit, and each one can invalidate an approved part when it is discovered late.
The programme drawing governs
Automotive part supply is released against the approved component drawing and its revision. A supplier recommendation does not replace a released drawing.
An application label is not an approval
Naming the vehicle system does not approve a material or a tube type. The programme specification and the material selection do.
The qualification plan is part of the scope
Where the part is qualified before production, the tests and evidence the plan requires belong on the enquiry, not on a later amendment.
Incoming inspection is agreed in advance
What is measured on receipt, at what frequency and against which drawing dimension is agreed before the first delivery.
Substitution needs release
A change of type, grade or condition on an existing part is a design change. It is released by the programme before it is quoted.
A change of type, grade or condition on a released part is a design change. The programme releases it first — this page supports the enquiry, it does not approve the substitution.
Repeat supply
What production supply has to control
A single order is judged on the material. A production programme is judged on whether the fifth delivery matches the first, and whether the paperwork still identifies it.
| Control | Why it matters | Before you enquire |
|---|---|---|
| Identity per bundle | Repeat supply fails at the point where two similar items are mixed, not at the mill. | Agree how type, grade and condition are recorded on packing and bundle schedules. |
| Consistency between lots | Production assumes lot-to-lot consistency in dimensions and condition. | State which characteristics are controlled between deliveries and how they are evidenced. |
| Documentation per delivery | The certificate has to follow the shipment, not a sample from an earlier lot. | Request certificates linked to the heat and the items actually supplied. |
| Change notification | A mill, origin or route change can invalidate an approved part. | Agree in writing who notifies whom when any of those change. |
| Protection in transit | Surface and end condition on arrival affect whether the part is fit to machine or assemble. | Define packing, end protection and handling requirements for the delivery route. |
Next decisions
Where the automotive route connects
Industrial and machinery tube supply carry the decisions this page depends on. The A513 standard page carries the type, grade and condition fields the drawing has to state.
- Name the component and its revision. Everything else is read against the drawing revision that released the part.
- State the governing specification. The structural, fluid or mechanical document the programme invokes sets the scope.
- Fix the type, grade and condition. Where a mechanical tube applies, each of the three is a separate field on the order.
- Agree the inspection scope. What is measured on receipt, how often, and against which drawing dimension.
- Settle the change rule. Agree who notifies whom when mill, origin, route or condition change between lots.
Related routes
The mechanical tube standard page carries the type, grade, condition and shape fields. Machinery and manufacturing supply carry the adjacent production decisions.
ASTM A513 Steel TubeSteel Tubes for MachinerySteel Tubes for Manufacturing
Enquiry
Turn a component requirement into a reviewable enquiry
Send the drawing revision, the governing specification, the tube type, grade and condition, the inspection scope and the delivery point. Availability and terms are confirmed in writing.
Price on request. Every figure, availability and delivery date requires written confirmation against a specific order.