Hot Rolled / SQR
Square Steel Bar
Hot rolled square steel bars per EN 10059 standard, from 10x10mm to 250x250mm.
Technical Specifications
Key Features
- Wide edge dimension range
- High flatness and straightness
- Surface suitable for welding and machining
- Available in structural and engineering steels
- Corner radii per standard
- Custom length cutting available
Applications
- Steel construction
- Machine frame manufacturing
- Mold and jig making
- Axle and shaft production
- Agricultural machinery
- General manufacturing sector
Dimension Table
| Form | Size Range | Standard | Steel Grades |
|---|---|---|---|
| Square | 10x10 - 25x25 mm | EN 10059 | S235JR, S355J2, C45, SAE1018 |
| Square | 25x25 - 50x50 mm | EN 10059 | S355J2, C45, 42CrMo4, C35 |
| Square | 50x50 - 100x100 mm | EN 10059 | 42CrMo4, C45, S355J2, 34CrNiMo6 |
| Square | 100x100 - 180x180 mm | EN 10059 | 42CrMo4, C45, S355J2G3, 34CrMo4 |
| Square | 180x180 - 250x250 mm | EN 10059 | 42CrMo4, C45, S355J2, 34CrNiMo6 |
Technical Notes
- 01Edge dimension tolerances per EN 10059 Table 1.
- 02Corner rounding radius depends on edge dimension.
- 03Flatness and twist tolerances guaranteed per standard.
- 04Ultrasonic testing recommended for large sections (>150mm).
What is a hot rolled steel bar?
A hot rolled bar is produced by shaping steel between rolls above its recrystallization temperature (~1100–1250°C), in round, square, hexagonal or flat sections. It is the most economical bar form; the surface carries a thin mill scale and tolerances are wide (EN 10060). It is the primary starting stock for machining, forging and cold drawing.
Production, tolerances and applications
A billet (~150×150 mm) is reheated and passed through successive rolling stands to reduce the section; hot deformation refines the grain and breaks up the cast structure. The mill scale and wide diameter tolerance mean precision applications need further processing (cold drawing, peeling, grinding → bright steel). Common grades: S235JR–S355J2 structurals, C45, 42CrMo4, 16MnCr5. Construction, machine building and forging stock are the biggest uses.
Frequently Asked Questions
What is the difference between hot rolled and cold drawn?+
Hot rolling is done at high temperature: economical but with scale and wide tolerances. Cold drawing is done at room temperature: tight tolerance (h9/h11), bright surface and higher yield strength from strain hardening.
What are hot rolled bar tolerances?+
Per EN 10060, roughly ±0.4 to ±2.0 mm depending on diameter; for precision work choose bright steel.
Which sections are produced?+
Round, square and hexagonal bars plus flats; round bar is the most common commercial form.
Where are hot rolled bars used?+
Machine parts, bolt/fastener blanks, forging stock, construction and general fabrication.
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