304 Stainless Steel Capillary Tube
Short Description:
ASTM A269 304 Stainless Steel Capillary Tube is a precision thin wall stainless steel tubing solution with good corrosion resistance, dimensional accuracy and clean surface quality. Available in customized outside diameter, wall thickness, length and inspection requirements.
304 Stainless Steel Capillary Tube Overview
304 Stainless Steel Capillary Tube is a precision thin-wall stainless steel tubing product for applications requiring small diameter, dimensional accuracy and smooth surface quality. ASTM A269 is commonly specified for this type of austenitic stainless steel tubing.
SAKY STEEL supplies 304 / UNS S30400 capillary tubing with customized outside diameter, inside diameter, wall thickness, fixed length and surface requirements. Bright annealed and polished surfaces are available according to the confirmed specification.
For precision capillary tubing, buyers should confirm not only the material grade but also OD, ID, wall thickness, cut length, tolerance and surface requirement.
Small Diameter / Thin Wall / Precision Dimensions / Fixed Length / Smooth Surface / Surface Roughness Inspection
304 Stainless Steel Capillary Tube Specifications
| Item | Specification |
|---|---|
| Grade | 304 / UNS S30400 |
| Standard | ASTM A269 |
| Product Type | Stainless Steel Capillary Tube |
| Outside Diameter | Customized Small Diameter |
| Inside Diameter | Customized according to OD and wall thickness |
| Wall Thickness | Thin Wall Customized |
| Length | Fixed Length / Customized |
| Surface | Bright Annealed / Polished |
| Surface Roughness | Inspection available according to confirmed requirement |
| Certificate | MTC / EN 10204 3.1 Available |
How to Specify Capillary Tube Size
Capillary tube dimensions are normally defined by outside diameter, inside diameter or wall thickness, together with the required finished length.
| Parameter | Meaning |
|---|---|
| OD | Outside Diameter |
| ID | Inside Diameter |
| WT | Wall Thickness |
| L | Finished Length |
304 Stainless Steel Capillary Tube Features
| Precision Dimensions
Small OD and thin-wall dimensional control |
Smooth Surface
Bright annealed or polished surface options |
Good Formability
Suitable for precision fabrication requirements |
Custom Cut Length
Fixed-length tubing according to order |
304 Stainless Steel Chemical Composition
304 stainless steel is an austenitic chromium-nickel stainless steel. Final batch composition should be confirmed by the supplied material test certificate.
| Element | Content |
|---|---|
| Carbon (C) | ≤0.08% |
| Chromium (Cr) | 18.0–20.0% |
| Nickel (Ni) | 8.0–10.5% |
| Manganese (Mn) | ≤2.0% |
| Silicon (Si) | ≤1.0% |
| Iron (Fe) | Balance |
Mechanical Properties
Mechanical properties depend on manufacturing process, heat treatment condition, tube dimensions and applicable specification.
| Property | Reference Requirement |
|---|---|
| Tensile Strength | ≥515 MPa |
| Yield Strength | ≥205 MPa |
| Elongation | ≥35% |
| Hardness | According to ASTM A269 requirements |
304 Capillary Tube Size Range
| Item | Supply Range |
|---|---|
| Outside Diameter | Customized Small Diameter |
| Inside Diameter | Customized |
| Wall Thickness | Thin Wall Customized |
| Length | Fixed Length / Customized |
| Surface | Bright Annealed / Polished |
Test & Inspection Evidence
The following inspection-report images are retained as actual document evidence. Results shown in these documents apply to the relevant tested sample or batch only.
 |
 |
 |
Precision Capillary Tube Processing
Production and finishing processes depend on the required tube dimensions and specification. Typical processing stages include:
Inspection and Quality Control
| Inspection Item | Purpose |
|---|---|
| Chemical Analysis | Verify stainless steel grade composition |
| Dimensional Inspection | Check OD, ID, wall thickness and length |
| Surface Inspection | Verify surface finish and appearance |
| Surface Roughness | Verify roughness when specified |
| Eddy Current Testing | Available when specified for tube integrity verification |
| MTC / EN 10204 3.1 | Material traceability documentation |
Applications of 304 Stainless Steel Capillary Tube
| Instrumentation
Measurement and control systems |
Laboratory Equipment
Precision fluid and gas components |
Analytical Equipment
Small-diameter transfer tubing |
| Sensors & Controls
Small tubing for precision systems |
Medical Components
Precision components subject to specification review |
Custom Components
Cut-to-length precision stainless tubing |
304 Stainless Steel Capillary Tube Packaging
SAKY STEEL uses suitable export packaging to protect capillary tubes against surface damage, contamination and bending during transportation.
FAQ
How should I specify 304 stainless steel capillary tube?
Please provide OD, ID or wall thickness, finished length, quantity and any requirements for tolerance, straightness or surface roughness.
Can surface roughness be inspected?
Yes. Surface roughness inspection can be performed according to the confirmed requirement.
Does Ra 0.135 μm apply to every capillary tube?
No. Ra 0.135 μm is the measured result shown for the displayed test sample only. It is not a universal guaranteed value for all 304 stainless steel capillary tubing.
Can capillary tubes be supplied in fixed lengths?
Yes. Fixed-length and customized cut-length tubing can be supplied according to the required dimensions and tolerance.
Need Precision 304 Stainless Steel Capillary Tube?
Send the required OD, ID or wall thickness, finished length, quantity, tolerance and surface requirement. SAKY STEEL can review the specification and provide a quotation.
