ST37 Transmission Shaft Steel | S235JR / St37-2 / 1.0037 Cold-Drawn Round and Hexagonal Bars
PRODUCT DESCRIPTION
ST37 / S235JR / 1.0037 transmission shaft steel consists of cold-drawn round and hexagonal solid bars that provide tighter dimensional control, a smoother surface and good machinability.MATERIAL INFORMATION
ST37 Transmission Shaft Steel | S235JR / St37-2 / 1.0037 Cold-Drawn Steel Bars
ST37 transmission shaft steel is a cold-drawn solid-steel product group used in general manufacturing, mechanical engineering and automation applications. At Saf Çelik, this product group is evaluated in round and hexagonal sections.
Transmission shaft steel is different from steel tube. This page covers cold-drawn solid steel bars requiring tighter dimensional tolerance, smoother surfaces and improved dimensional accuracy; it does not cover seamless or welded ST37 tubes.
ST37, S235JR and 1.0037 References
| Common Designation | Modern / European Reference | Material Number | Description |
|---|---|---|---|
| ST37 / St37-2 | S235JR | 1.0037 | Common structural-steel reference for the former German ST37 designation |
| Cold-drawn transmission shaft steel | S235JR +C Also seen as S235JRC in commercial lists |
1.0037 | Commercial expression used for cold-drawn solid steel |
Important note: ST37 is a broad and older commercial designation. Rather than specifying only “ST37,” an order should state S235JR / 1.0037, product shape, tolerance class, delivery condition and certificate requirement.
Why Choose Cold-Drawn Transmission Shaft Steel?
Cold drawing is the process of drawing steel through a die to achieve the required final dimension. Compared with hot-rolled solid bar, it can provide more controlled diameter or across-flats dimensions, smoother surface quality and better dimensional accuracy.
- Closer dimensional control in round and hexagonal sections
- Smoother and cleaner surface quality
- Reduced preparation before machining
- Suitable for turning, milling and general manufacturing
- Efficient use in parts requiring accuracy, straightness and specified tolerance
Cold drawing can change yield and tensile behavior. Exact mechanical values depend on the cold-reduction ratio, section size, delivery condition and product certificate.
Chemical Composition
Chemical limits for ST37 / S235JR / 1.0037 can vary by applicable standard. The following values are general references for the S235JR grade family.
| Element | General Reference Value |
|---|---|
| Carbon (C) | max. 0.17% May vary by applicable standard in thicker sections |
| Manganese (Mn) | max. 1.40% |
| Phosphorus (P) | max. 0.035% |
| Sulfur (S) | max. 0.035% |
| Nitrogen (N) | max. 0.012% |
Older standards and references may show phosphorus and sulfur limits of 0.045% for ST37. The specified current S235JR standard and product certificate should govern the order.
Mechanical Properties: Base Grade and Cold-Drawn Condition
The following basic values apply to the S235JR hot-rolled reference under EN 10025-2. They are not direct certificate values for cold-drawn transmission shaft steel, because cold-drawn properties can vary according to section size and degree of cold reduction.
| Nominal Section | Yield Strength | Tensile Strength | Elongation |
|---|---|---|---|
| ≤16 mm | min. 235 MPa | 360 – 510 MPa | min. 24% |
| 16 – 40 mm | min. 225 MPa | 360 – 510 MPa | min. 24% |
| 40 – 100 mm | min. 215 MPa | 360 – 510 MPa | min. 23% |
For the S235JR grade family, 27 J Charpy V impact energy at +20°C is one of the basic requirements within the relevant standard scope. Final mechanical values and tolerances for transmission shaft steel must be confirmed by the certificate of the quoted cold-drawn product.
Product Forms and Tolerances
Saf Çelik can evaluate the ST37 transmission product group in the following solid sections:
- Cold-drawn round steel bars
- Cold-drawn hexagonal steel bars
Required diameter or across-flats dimension, length, straightness, surface condition and tolerance class should be stated during quotation. For precision-machining applications, EN 10278 or the tolerance requirement in the customer drawing should be considered.
Machinability and Weldability
ST37 / S235JR offers good weldability and formability because of its low carbon content. With a suitable welding method, section thickness and service conditions, MIG/MAG, TIG or arc welding can be considered.
Where cold-drawn transmission shaft steel is welded, the effect of welding heat input on dimensional accuracy and surface quality should be assessed. Precision-tolerance parts may require straightening or further machining after welding.
The controlled surface and dimensions of transmission shaft steel can reduce preparation time before machining. However, free-machining steel and transmission shaft steel are not the same product group: free-machining steels should be assessed separately where exceptionally efficient chip breaking is required in automatic machining.
Applications
- General machinery shafts and connection elements
- Auxiliary components in conveyor, gearbox and transmission systems
- Machined components for hydraulic, pneumatic and automation equipment
- Bolts, nuts, pins and connection elements
- Turned and milled parts requiring controlled dimensions and surface quality
- Connection, bush and special-manufacturing components requiring hexagonal sections
Frequently Asked Questions
Is ST37 transmission shaft steel the same product as ST37 tube?
No. ST37 transmission shaft steel is a cold-drawn round or hexagonal solid-bar product. ST37 tube is a different product with different production standards, dimensions and applications.
Do ST37, S235JR and 1.0037 mean the same thing?
ST37 is an older German commercial designation, while S235JR and 1.0037 are modern European references. Full identification must still be used when ordering because product standard, delivery condition and certification details can differ.
Why choose cold-drawn transmission shaft steel?
Cold drawing can provide closer dimensions, a smoother surface and better dimensional accuracy. These characteristics are valuable for machined components and machine parts requiring specified tolerances.
Request a Quote from Saf Çelik
For ST37 / S235JR / 1.0037 transmission shaft steel, please share the required section shape, diameter or across-flats dimension, length, tolerance, surface condition, quantity and certificate requirement. Saf Çelik can help identify the appropriate cold-drawn round or hexagonal steel option for your project.