Free-Cutting Steel Bright Bar
Introduction:
Free-cutting steel bright bar is a high-precision finished material specially optimized for high-efficiency automatic CNC turning and mass precision machining. By rationally compounding sulfur, manganese and other free-machining elements, the steel achieves excellent chip-breaking performance, extremely low cutting resistance and minimal tool wear, greatly improving machining efficiency and workpiece surface finish.
Product Overview
Free-cutting steel bright bar is a high-precision finished material specially optimized for high-efficiency automatic CNC turning and mass precision machining. By rationally compounding sulfur, manganese and other free-machining elements, the steel achieves excellent chip-breaking performance, extremely low cutting resistance and minimal tool wear, greatly improving machining efficiency and workpiece surface finish. According to customer precision and surface requirements, products can be selectively finished by cold drawing, centerless turning (peeling) and centerless grinding. The product complies with GB/T 8731, ASTM A29/A29M, EN 10087 and other international standards, covering diameter range of ø12–90 mm. It covers full-series mainstream grades including 1215, GT1215S, 11SMn30, 11SMn37, SAE1144, SAE1141, 45S10, 45S20, Y08-45 and S45CL. Finished bright bars feature mirror smooth surface, no oxide scale, high dimensional accuracy and stable batch hardness. It is the preferred material for batch production of small and medium-sized precision mechanical parts, widely used in instrumentation, auto parts, hydraulic accessories, hardware fittings and export mechanical components.
Representative Grades
|
Grade |
Core Characteristics |
Typical Application |
|
1215 / GT1215S |
Lead-free low carbon free-cutting steel, excellent machinability, good plasticity, environmental friendly, easy electroplating |
Instrument shafts, pin shafts, small fasteners, camera hardware, electroplated precision parts |
|
11SMn30 / 11SMn37 |
European standard sulfur-manganese free-cutting steel; 11SMn37 higher sulfur content, better cutting performance |
EU export machinery parts, automation equipment small shaft, valve accessories, sensor components |
|
SAE1141 / SAE1144 |
Medium carbon free-cutting steel, can be quenched & tempered, higher strength than low carbon grades |
Medium-load shaft parts, pump shafts, transmission pin, automobile connecting components |
|
45S10 / 45S20 |
Medium carbon domestic free-cutting steel, balanced strength and cutting property |
General machinery shaft sleeves, threaded fittings, engineering standard parts |
|
Y08-45 |
Domestic serial free-cutting structural steel, wide carbon range, multiple strength grades |
Domestic hardware, textile machinery parts, hydraulic valve bodies, customized machined parts |
|
S45CL |
Improved free-cutting medium carbon steel, optimized for continuous automatic lathe processing |
High-volume auto accessories, bearing spacer sleeves, precision gear blanks |
Grade Description
-
01
1215 and GT1215S: American standard lead-free low-carbon free-cutting steel, environmentally friendly material, suitable for electroplating processes; GT1215S is an improved and upgraded version with higher purity.
-
02
11SMn30 and 11SMn37: European standard sulfur-manganese free-cutting steels. 11SMn37 has a higher sulfur content and better cutting performance, and is intended for export orders to Europe.
-
03
SAE1141 and SAE1144: American standard medium carbon free-cutting steel, supports quenching and tempering heat treatment, used for load-bearing parts with strength requirements.
-
04
45S10, 45S20, Y08-45: Domestic series of free-cutting structural steels, covering the low-carbon to medium-carbon range, to meet the needs of large-scale machining in China.
-
05
S45CL: Improved medium carbon free-cutting steel, optimized for continuous machining on fully automatic lathes.
Product Specifications
|
Item |
Parameter |
|
Product Form |
Hot rolled bar / Cold drawn bright bar / Peeling & grinding bright bar |
|
Diameter Range |
ø12 mm – ø90 mm |
|
Standard Length |
3m / 6m / 9m, fixed-length cutting available |
|
Delivery Condition |
Hot rolled, cold drawn, annealed, stress-relieved |
|
Dimensional Tolerance |
Hot rolled: h11~h13; Cold drawn bright bar: h8~h10; Peeled bar: h7~h9 |
| Surface Quality |
Mirror bright, oxide-free, crack-free, scratch-free, uniform surface texture |
|
Straightness |
Standard ≤1.2mm/m; High precision ≤0.4mm/m |
|
Inspection Standard |
Chemical composition analysis, hardness test, surface inspection, ultrasonic test optional |
Core Advantages
1. Excellent Ultra-Fine Machinability: Optimized sulfur-manganese inclusion distribution forms short broken chips during turning, reducing cutting resistance and tool loss significantly, improving continuous CNC mass production efficiency.
2. Complete Global Grade System: Integrates Chinese, American and European standard free-cutting steel grades, realizing one-stop procurement for domestic processing and export orders.
3. Diversified Precision Finishing Options: Support cold drawing, centerless peeling and centerless grinding processes to meet different tolerance, straightness and surface roughness requirements of high-precision parts.
4. Stable & Reliable Quality: Strict chemical composition and hardness control, uniform microstructure, extremely small batch fluctuation, ensuring consistent machining performance in long-term continuous production.
5. High Processing Efficiency & Low Cost: Bright bar finished surface eliminates rough turning process, saves processing time and reduces production cost for precision parts.
6. Wide Specification Coverage: Full size range from ø12–90mm, covering miniature precision pins, small shafts and medium-sized mechanical shaft blanks for diverse industrial needs.
Main Application Fields
-
Instrument & Electronic Components
1215, GT1215S for miniature shafts, positioning pins, camera and sensor hardware parts.
-
Automotive Spare Parts
SAE1141, SAE1144, S45CL for auto small shafts, connecting pins, bushings, throttle accessories.
-
Export European & American Mechanical Parts
11SMn30,11SMn37,1215 for automation equipment, valve parts, hydraulic fittings for overseas customers.
-
General Hardware & Textile Machinery
45S10,45S20,Y08-45 for thread fittings, shaft sleeves, textile machine moving components.
-
Hydraulic & Pneumatic Components
Precision valve cores, guide pins, sealing shaft parts produced by continuous CNC turning.
Packaging & Services
- 1. Executive Standards: GB/T 8731, ASTM A29/A29M, EN 10087, fully compliant with domestic and international precision free-cutting steel standards.
- 2. Complete Inspection & Certification: Provide official MTC 3.1 mill test certificate per batch; support SGS, BV third-party inspection and factory witness testing for export customs clearance.
- 3. Professional Exclusive Packaging for Bright Bars: Adopts special scratch-proof and rust-proof precision packaging for bright bars, wrapped with thickened waterproof film on the outer layer and firmly bundled and fixed. High-precision and long-size products can be customized with solid wooden box packaging, completely avoiding collision, scratches, deformation and rust during transportation, suitable for long-distance sea and land transportation.
- 4. Flexible Order Shipment: 1 ton MOQ per grade, support mixed grades and mixed sizes container loading.
- 5. Custom Deep Processing: Optional cold drawing, centerless turning (peeling), centerless grinding, fixed-length cutting, stress relief annealing and surface precision finishing customization.
- 6. Professional Technical Support: Provide machining process guidance, parameter optimization and steel grade selection matching services for automatic lathe mass production.
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Contact Us
- WhatsApp: +86-185 9567 2991
- Email: martinliu@rongtianmetal.com
- Tel: +86-185 9567 2991
- Address: 8F, Bldg 2, Jinke Zhihui Valley No. 65 Hongyuan Rd., Jinshui Dist. Zhengzhou, China.
