Product family 02 / Round steel bars
Hot rolled, forged, bright and precision-ground round bars for machining, forging and equipment manufacturing. The grade, diameter, surface condition and heat-treatment requirement are confirmed as one route.
Technical data, process & buyer resources ↓
Product range
A bar is not defined by diameter alone. Surface condition, straightness expectation, heat treatment and cut length all affect what should be quoted.
The table keeps size and condition open until the inquiry defines them. It lists the original grade references without implying that every grade is held in every finish.
| Product form | Original grade references | Size basis | Condition / coordination |
|---|---|---|---|
| Carbon steel round bars | 20#, 35#, 45#, 50#, Q235, Q355 | Diameter and length stated in the inquiry | Surface state, cutting and packing agreed per order |
| Alloy steel round bars | 20Cr, 40Cr, 20CrMnTi, 35CrMo, 42CrMo, 38CrMoAl | Diameter and length stated in the inquiry | Heat-treatment and inspection requirements confirmed |
| Hot rolled round bars | Supplied grade to be confirmed | Diameter and length defined by the order | Scale condition, straightness expectation and cutting |
| Forged round bars | Supplied grade to be confirmed | Diameter and length defined by the order | Forging route, allowance and downstream machining |
| Bright round bars | Supplied grade to be confirmed | Diameter and length defined by the order | Bright surface, straightness and packing |
| Precision ground round bars | Supplied grade to be confirmed | Dimensions and tolerance agreed from inquiry | Ground condition, straightness and surface protection |
| Quenched & tempered round bars | 40Cr, 42CrMo, 35CrMo, 4140, 4340 references | Diameter and length stated in the inquiry | Q&T condition, hardness requirement and inspection |
| Cut-to-length round bars | Supplied grade to be confirmed | Cut length defined by the order | Cutting, end condition, bundling and packing |
No stock size range is implied by this page. Availability, tolerances and documentation are confirmed against the actual inquiry and agreed order.
The source also names AISI 1045, 4140, 4340 and 8620; EN8, EN19, EN24 and 16MnCr5. These are useful reference points, not a substitute for the purchase specification. Grade, heat-treatment condition and mechanical requirements must be confirmed before an alternative is accepted.
TECHNICAL / BUYER REFERENCE
Use these public technical references to define an order. They do not state RUNSU stock, batch test results or committed machining capacity. Grade and delivery-condition limits accompany the data.
| Grade reference | Material family | Specify |
|---|---|---|
| C45 | Medium-carbon engineering steel | Delivery state, subsequent heat treatment and section size |
| 42CrMo4 | Alloy steel for quenching and tempering | Section, strength, toughness and condition |
| 16MnCr5 | Alloy case-hardening steel | Case requirements and final performance specification |
Ovako · C45 material data ↗ · Ovako · 16MnCr5 material data ↗
| Datasheet dimension band (mm) | Yield min (MPa) | Tensile (MPa) | A₅ min | HB |
|---|---|---|---|---|
| 25 < 40 | 750 | 1000–1200 | 11% | 300–350 |
| 40 < 100 | 650 | 900–1100 | 12% | 270–320 |
| 100 < 160 | 550 | 800–950 | 13% | 240–280 |
Band notation follows the source. Values apply to this Ovako variant and +QT state, not every 42CrMo4/4140 product or RUNSU shipment. Confirm boundary sizes, sampling and requirements against the agreed specification.
| Delivery form | Specify | Inspection focus |
|---|---|---|
| Hot rolled / forged | Diameter, length, surface and machining stock | Size, straightness, surface condition and heat identity |
| Peeled / bright | Diameter limits and surface condition | A bright finish alone does not define a tolerance |
| Ground | Diameter tolerance, roundness, straightness, Ra (µm) | Drawing-defined measurement points and methods |
| Quenched and tempered | Condition, mechanical properties/hardness and sampling | Dimensions and material documents together |
Start from the final component drawing to define blank diameter, cut length and machining stock.
Agree hot-rolled, forged, annealed or Q&T condition before surface processing.
Coordinate the specified cutting, peeling or grinding route.
Verify size, state, heat identity and documents. Retain identification for downstream work.
Estimate material and shipping mass using 7,850 kg/m³. Actual dimensions, grade and packaging affect shipment mass; weighing and order terms govern.
kg/m = π / 4 × D² × 0.00785
Total kg = kg/m × length × quantity; D and t in mm, length in m. Packaging and machining losses excluded.
References checked 19 October 2026. The agreed standard edition, drawing, technical agreement and material certificate govern supply and acceptance.
Processing coordination
Bar processing is coordinated according to the drawing, the intended machining operation and the condition required on arrival.
Cutting to the required bar length for the agreed order.
Surface preparation discussed according to the finish requirement.
Machining preparation coordinated against the downstream drawing.
Treatment requirements confirmed for the grade and application.
Q&T coordination where the order specifies the condition.
Straightness, dimensional and packing checks within the agreed scope.
Applications
Round bar requirements often begin with the part to be machined and the condition the machine shop needs.
Procurement FAQ
Clarify these points before quoting so the technical and commercial reviews start from the same information.
Provide the grade or standard, diameter, length, quantity, surface condition and heat-treatment requirement. Add the application and the machining operation if known.
They should not be treated as the same condition. Surface preparation, tolerance and straightness requirements need to be stated and confirmed against the proposed supply.
State the required condition, hardness or mechanical property requirement and the applicable standard. The final treatment route is confirmed against the grade and drawing before production.
Yes, cut-to-length requirements can be evaluated. Give the finished length, quantity, allowable tolerance and packing method so the cutting and logistics route is clear.
Send the grade, diameter, length, quantity, surface condition, heat-treatment requirement and destination. A drawing is welcome.
