Drawn Over Mandrel Steering Shaft Tubing for Automotive Application with ASTM

Steering shaft tubing is a precision mechanical steel tube designed for automotive steering column and intermediate steering shaft assemblies. Drawn Over Mandrel (DOM) tubing is manufactured from electric-resistance-welded tube followed by cold drawing through a die and over a mandrel. This process improves dimensional accuracy, wall-thickness uniformity, concentricity, inside-surface quality, and mechanical performance.

For steering shaft production, these characteristics are particularly important because the tube may subsequently undergo spline forming, swaging, machining, welding, press fitting, or telescopic assembly. ASTM A513 Type 5 is one of the principal specifications used for DOM mechanical tubing, while EN 10305-2 provides comparable requirements for cold-drawn welded precision steel tubes.

Unlike ordinary as-welded mechanical tubing, DOM tubing is cold drawn through tooling that controls both the outside and inside surfaces. This allows tighter control of OD, ID, wall thickness, and concentricity, which is important where steering shaft tubes are assembled with bearings, sleeves, bushings, universal joints, or telescopic components.

The mandrel drawing process reduces wall eccentricity and produces a more uniform tube section. Uniform wall distribution helps maintain consistent torsional behavior and reduces dimensional variation during spline forming, swaging, machining, and press-fit operations.

Cold working increases the strength of DOM tubing. For example, stress-relieved ASTM A513 Type 5 SAE 1026 tubing can provide minimum yield strength around 448 MPa and minimum tensile strength around 517 MPa, depending on size and delivery condition.

The mandrel controls the internal surface during drawing, producing a smoother and more dimensionally consistent bore than conventional ERW tubing. This is valuable for telescopic steering shafts and components that require controlled internal sliding or machining.

Low-carbon and medium-carbon DOM grades can be selected for machining, welding, forming, spline manufacturing, end reduction, drilling, boring, and other automotive fabrication processes.

A common purchasing concern for steering shaft tubing is excessive eccentricity between the outside diameter and inside diameter. Poor concentricity can affect machining allowance, spline geometry, bearing engagement, and rotational balance.

The DOM process sizes the tube over an internal mandrel, allowing the OD, ID, and wall distribution to be controlled simultaneously. Tubes can also be supplied according to specified OD/ID combinations rather than OD/wall thickness alone when the final steering-shaft design requires precise internal dimensions.

Steering shaft manufacturers often perform spline forming, swaging, end forming, machining, or welding after tube delivery. Excessive cold work can make subsequent deformation difficult or cause dimensional instability.

Different delivery conditions can therefore be selected according to the manufacturing route. Stress-relieved tubing provides a balance between strength and residual-stress control, while annealed or normalized tubing can provide improved ductility when substantial forming is required.

Automotive steering components require repeatability between production batches. Differences in tube hardness, wall thickness, chemical composition, or dimensional tolerance can directly affect machining parameters and assembly consistency.

Material can be supplied with heat-number traceability, dimensional inspection records, chemical analysis, tensile-test results, and additional inspection documentation according to the purchase specification. Critical OD, ID, wall thickness, straightness, and surface requirements should be clearly defined on the customer's drawing or purchase order.

DOM steel tubing is used to manufacture the tubular body of an automotive intermediate steering shaft connecting the steering column to the steering gear. The tube may be machined, splined, swaged, welded to yoke components, or incorporated into a telescopic section depending on the steering system design.

Its controlled OD, ID, concentricity, and mechanical properties help maintain accurate fit with mating components while supporting the torsional loads transmitted through the steering system.

A: Manufacturer, also can do trading.

A: Generally speaking, it is 10-15 days if the goods are in stock, or it is 30-40 days if the goods are not in stock, it is according to quantity.

A: Yes, we could offer the sample for free charge but need pay the cost of freight.

A: Payment ≤ 2000 USD, 100% in advance. Payment ≥ 2000 USD, 30% T/T in advance, balance before shipment. If you have another question, please feel free to contact with me.