Premium 303 Stainless Steel Bar With Tolerance Within 0.05mm for High-Speed Machining Projects

Products Specification

Premium 303 Stainless Steel Bar With Tolerance Within 0.05mm for High-Speed Machining Projects

The 303 stainless steel grinding bar is a precision-engineered, free-machining alloy specifically developed for demanding, high-speed machining environments. Known for its tight tolerance control, exceptional machining behavior, and reliable corrosion resistance, it is one of the most preferred materials for producing precision components in aerospace, automotive, medical device, and electronic hardware industries.

Manufactured through centerless grinding, cold finishing, and strict dimensional inspection, this grade delivers a uniform diameter with a tolerance controlled within ±0.05mm. This precision allows machinists and engineers to drastically reduce secondary finishing operations while improving production efficiency and surface quality.

With a bright, polished appearance and consistent mechanical properties, the Premium 303 Stainless Steel Grinding Bar supports high-speed CNC machining, screw machining, and automated turning operations without excessive tool wear.

1. Product Overview

The 303 stainless steel grinding bar belongs to the 18-8 stainless family but distinguishes itself with superior machinability due to its elevated sulfur content. Its optimized composition ensures smooth chip breaking, shorter machining cycles, and enhanced dimensional stability.

Designed for precision manufacturing, this product is frequently used for components requiring tight tolerances, smooth surfaces, and fast machining turnover. Its bright ground finish also makes it suitable for both performance-critical and visually exposed parts.

Key Product Highlights

• Tolerance within ±0.05mm achieved through precision grinding

• Excellent machinability, ideal for fast CNC cutting and turning

• Bright ground surface with minimal surface defects

• Consistent diameter across the full bar length

• Corrosion resistance suitable for general industrial environments

• Reduced tool wear and shorter machining times

• Available diameters: 3mm – 80mm (custom up to 150mm)

2. Chemical Composition

303 stainless steel is formulated to ensure optimal performance in machining applications while retaining the desirable corrosion resistance of the austenitic family.

Table 1: Chemical Composition (%)

The sulfur addition dramatically improves chip formation, making 303 the preferred choice for high-speed cutting, especially on automatic lathes and CNC turning centers.

3. Mechanical Properties

The Premium 303 Stainless Steel Grinding Bar combines machinability with mechanical reliability. The following values represent typical properties for annealed material.

Table 2: Mechanical Properties

These characteristics allow the bar to be used for medium-strength precision parts subjected to rotational force, light impact, or structural loads.

4. Physical Properties

303 stainless steel retains stability under temperature variation, making it favorable for components that experience intermittent or moderate heat during machining.

Table 3: Physical Properties

These properties contribute to the material’s consistent performance in machining and moderate-temperature industrial environments.

5. Precision Grinding & Tolerance Control

Unlike standard bright bars, the Premium 303 Stainless Steel Grinding Bar undergoes specialized centerless grinding and calibration processes to achieve the requested ±0.05mm tolerance.

Benefits of Precision Ground Bars

• Extremely smooth surface without scale

• Improved diameter consistency

• Low friction during machining

• Reduced chatter and vibration

• Minimal straightness deviation

• Ready-to-machine condition with fewer secondary operations

Table 4: Precision Attributes

Such precision ensures superior results in aerospace fittings, instrument parts, and medical tooling.

6. Available Sizes & Length Options

The grinding bars are available in a wide size range and can be customized for OEM production.

Table 5: Standard Dimensions

7. Surface Finish Options

The grinding process ensures a premium finish suitable for high-end precision components.

Table 6: Surface Finishes

8. Application Fields

303 stainless steel grinding bars are widely used in industries where machining efficiency is critical.

Industries Using 303 Grinding Bars

• Aerospace engineering

• Automotive manufacturing

• Medical equipment production

• Electronic device manufacturing

• Industrial automation

• Precision instrument fabrication

• Food processing machinery

• Marine equipment (mild conditions)

Common Machined Parts

• Precision shafts and axles

• Valve stems & pump components

• Instrument pins & probe rods

• Fasteners such as bolts and studs

• Bushings and collars

• Aerospace fittings

• Medical tool handles and fixtures

• Custom CNC-machined parts

The combination of high machinability and tight tolerances makes the 303 grinding bar ideal for complex geometries and high-volume production.

9. Comparison With Similar Stainless Steel Grades

Table 7: Grade Comparison (303 vs. 304 vs. 316)

For high-efficiency machining projects, 303 is the superior choice.

10. Manufacturing Process Flow

1. Hot Rolling – Initial forming of raw stainless steel

2. Cold Drawing – Improved dimensional accuracy and hardness

3. Centerless Grinding – Achieves ±0.05mm tolerance

4. Straightening – Reduces bending deviation

5. Surface Treatment – Bright, ground, or polished finish

6. Cutting to Custom Lengths

7. Final Inspection – Dimensional and visual inspection

The multi-step precision process ensures the bars meet the strictest performance expectations.

11. Quality Assurance & Certifications

All grinding bars undergo rigorous testing:

• Dimensional accuracy test

• Surface roughness test

• Chemical composition analysis

• Mechanical performance test

• Straightness and roundness inspection

• Ultrasonic flaw detection (optional)

Certifications Available

• ASTM / AISI compliance

• EN & JIS material standards

• RoHS and REACH compliance

• Mill Test Report (MTR)

12. Packaging & Delivery

To preserve surface quality during transport:

Packaging Options

• Anti-rust paper wrapping

• Plastic protective sleeves

• Wooden cases or crates

• Steel-strapped bundles

Shipping Options

• Sea freight for bulk shipments

• Air freight for urgent orders

• Courier express for sample quantities

13. Why Choose Our Premium 303 Stainless Steel Grinding Bar?

• Guaranteed ±0.05mm tolerance

• Consistent, defect-free bright surface

• High availability of stock diameters

• Custom machining and length services

• Competitive pricing for industrial quantities

• Professional engineering support

Whether you are producing thousands of CNC parts or developing a high-precision prototype, our 303 Stainless Steel Grinding Bars deliver the performance and consistency required for high-speed machining projects.