Hot Rolled / FLT
Flat Steel Bar
Hot rolled flat steel bars per EN 10058 and EN 10092 standards, from 10x3mm to 150x60mm.
Technical Specifications
Key Features
- Width and thickness combinations
- Wide grade range including spring steels
- Edge straightness and surface quality
- Suitable for welding and bending
- Available in Q&T and structural steels
- Economical cross-section options
Applications
- Spring manufacturing (leaf springs)
- Steel construction
- Blade and tool making
- Agricultural equipment
- Transportation sector
- General manufacturing
Dimension Table
| Form | Size Range | Standard | Steel Grades |
|---|---|---|---|
| Flat | 10x3 - 30x5 mm | EN 10058 | S235JR, S355J2, C45, 51CrV4 |
| Flat | 30x5 - 60x10 mm | EN 10058 | S355J2, C45, 51CrV4, 60SiMn5 |
| Flat | 60x10 - 100x20 mm | EN 10058 | 42CrMo4, C45, 51CrV4, S355J2 |
| Flat | 100x20 - 130x40 mm | EN 10058 | 42CrMo4, C45, S355J2, 60SiMn5 |
| Flat | 130x40 - 150x60 mm | EN 10092 | 51CrV4, 60SiMn5, C45, 42CrMo4 |
Technical Notes
- 01Width and thickness tolerances controlled separately per EN 10058.
- 02Surface decarburization controlled for spring steels (51CrV4, 60SiMn5).
- 03EN 10092 applies special tolerance and surface conditions for spring steels.
- 04Edge condition: as-rolled edge or sheared edge available.
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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