Introduction
Stainless steel round bars are widely used in machining, fabrication, construction, automotive, chemical processing and industrial equipment manufacturing. Selecting the correct round bar size requires understanding diameter specifications, weight per meter, tolerance grades and available standards.
This stainless steel round bar size and weight chart provides common metric and imperial dimensions, calculated weight values, the standard weight formula and guidance on tolerance selection including h9, h11 and k12 grades.
Whether you are purchasing stainless steel round bar for CNC machining, precision components or structural applications, accurate size and weight calculation helps optimize material cost and production planning.
Quick Answer: How much does stainless steel round bar weigh?
The approximate weight of stainless steel round bar can be calculated using:
Weight (kg/m) = Diameter × Diameter × 0.00623
- Diameter unit: millimeter (mm)
- Density assumption: approximately 7.93 g/cm³ for common stainless steel grades
- Example: Ø20 mm stainless steel round bar:20 × 20 × 0.00623 ≈ 2.49 kg/m
Stainless Steel Round Bar Size Chart (Metric)
Metric stainless steel round bars are commonly supplied according to diameter measurements in millimeters. The following table lists popular sizes and approximate weight per meter.
| Diameter (mm) | Weight (kg/m) | Common Applications |
|---|---|---|
| 6 | 0.22 | Small machining parts |
| 10 | 0.62 | Fasteners, shafts |
| 12 | 0.90 | General machining |
| 16 | 1.60 | Mechanical components |
| 20 | 2.49 | Shafts and precision parts |
| 25 | 3.89 | Industrial fabrication |
| 30 | 5.61 | Heavy machining |
| 40 | 9.97 | Industrial shafts |
| 50 | 15.58 | Heavy components |
Stainless Steel Round Bar Size Chart (Imperial)
Imperial stainless steel round bars are commonly specified in inches for North American markets.
| Diameter (inch) | Approx. Diameter (mm) | Weight (kg/m) |
|---|---|---|
| 1/4″ | 6.35 | 0.25 |
| 1/2″ | 12.7 | 1.01 |
| 3/4″ | 19.05 | 2.26 |
| 1″ | 25.4 | 4.02 |
Stainless Steel Round Bar Weight Calculation Formula
The weight of stainless steel round bar depends on diameter, length and material density.
For common stainless steel grades such as 304, 304L, 316 and 316L, the practical calculation formula is:
Weight (kg/m) = D² × 0.00623
Where:
- D = Round bar diameter in millimeters
- 0.00623 = Stainless steel density conversion factor
Example:
A 316 stainless steel round bar with diameter 30 mm:
30 × 30 × 0.00623 = 5.61 kg/m
Stainless Steel Round Bar Tolerance Grades (h9, h11, k12)
For precision machining applications, stainless steel round bars are often supplied according to dimensional tolerance grades. The tolerance determines how much the actual diameter can deviate from the nominal size.
Common tolerance grades for stainless steel precision round bars include h9, h11 and k12.
| Tolerance Grade | Description | Typical Applications |
|---|---|---|
| h9 | Precision tolerance with tighter dimensional control | CNC machining, precision shafts, automatic machinery parts |
| h11 | General precision tolerance for machined components | Mechanical parts, general machining |
| k12 | Positive tolerance suitable for fitting requirements | Special assembly applications |
How to Select Stainless Steel Round Bar Tolerance
- Choose h9 tolerance when machining accuracy and dimensional consistency are critical.
- Choose h11 tolerance for general engineering and standard machining applications.
- Choose k12 tolerance when a specific fitting condition requires controlled positive deviation.
- For bearing, shaft and automatic machinery applications, precision tolerance should be confirmed before ordering.
Common Stainless Steel Round Bar Grades
| Grade | Characteristics | Applications |
|---|---|---|
| 304 Stainless Steel Round Bar | Excellent corrosion resistance and fabrication performance | Food equipment, general machinery, construction |
| 316 Stainless Steel Round Bar | Improved corrosion resistance due to molybdenum addition | Marine, chemical and pharmaceutical equipment |
| 17-4PH Stainless Steel Round Bar | High strength precipitation hardening stainless steel | Aerospace, shafts and high strength components |
| 420 / 440C Stainless Steel Round Bar | High hardness martensitic stainless steel | Cutting tools, bearings and wear parts |
Stainless Steel Round Bar Standards
Stainless steel round bars are commonly manufactured according to international standards depending on grade, product form and customer requirements.
| Standard | Application |
|---|---|
| ASTM Standards | Common specification system for stainless steel bars and industrial products |
| EN Standards | European dimensional and material designation requirements |
| JIS Standards | Japanese industrial material specifications |
Applications of Stainless Steel Round Bars
Stainless steel round bars are used in a wide range of industries because of their corrosion resistance, strength and machining performance.
- CNC machining components and precision shafts.
- Automotive parts and mechanical transmission components.
- Food processing equipment and sanitary machinery.
- Chemical processing equipment.
- Marine components exposed to corrosive environments.
- Construction and architectural structures.
- Industrial fasteners and fabricated parts.
How to Choose the Right Stainless Steel Round Bar Size
Selecting the correct stainless steel round bar size depends on application requirements, machining allowance, load conditions and final dimensions.
| Application | Recommended Consideration |
|---|---|
| CNC Machining | Select suitable diameter with machining allowance and tolerance grade |
| Shaft Manufacturing | Consider strength, hardness and dimensional accuracy |
| Structural Use | Consider diameter, load and corrosion environment |
Frequently Asked Questions About Stainless Steel Round Bars
How do you calculate stainless steel round bar weight?
The approximate weight can be calculated using diameter squared multiplied by 0.00623 for stainless steel round bars.
What is the weight of a 20mm stainless steel round bar?
A 20mm stainless steel round bar weighs approximately 2.49 kg per meter.
What tolerance should I choose for precision machining?
For precision machining, h9 tolerance is commonly selected. General machining applications may use h11 tolerance depending on requirements.
What stainless steel round bar grades are commonly available?
Common grades include 304, 304L, 316, 316L, 17-4PH, 420 and 440C stainless steel round bars.
Stainless Steel Round Bar Solutions from SAKY STEEL
SAKY STEEL supplies stainless steel round bars in various grades, diameters, surface finishes and tolerance requirements for global industrial customers.
Our stainless steel bars are available in standard and customized sizes, including precision ground round bars for machining applications.
We provide material traceability documents, inspection support and customized production solutions according to customer requirements.
For stainless steel round bar inquiries, please provide grade, diameter, length, quantity and tolerance requirements.
Conclusion
Understanding stainless steel round bar sizes, weight calculation methods and tolerance grades helps engineers and buyers select the correct material for their applications.
From standard diameters to precision ground bars, SAKY STEEL provides stainless steel round bar solutions for machining, manufacturing and industrial projects worldwide.
Post time: Jul-23-2026