stainless steel
capillary tube
Stainless steel pipe & tube is all we do. ASTM A632 / A269 capillary tube in 304 and 316L with OD tolerance from ±0.05 mm, orders from 100 pieces per size, standard samples dispatched within 48 hours (freight collect) and S3 clean bore on request.
OD 0.1–5.0 mm · Wall thickness 0.03–1.0 mm · Straight lengths up to 6 m · Continuous coils exceeding 15,000 m
ASTM A632 Stainless Capillary Tubing with Low 100-Piece Trial Minimums
ASTM A632 capillary tubes in grades 304, 304L, 316, and 316L with OD tolerance from ±0.05 mm and S3 clean bore on request.
Specifications
Standard Capillary Size & Precision Matrix
| Outer Diameter (OD) | Wall Thickness (WT) | Standard OD Tol. | Ultra-Precision Tol. | WT Allowance | Length Options |
|---|---|---|---|---|---|
| 0.10 – 0.50 mm | 0.03 – 0.15 mm | ±0.03 mm | ±0.010 mm | ±10% | Coil / Cut (10–1000mm) |
| 0.51 – 1.00 mm | 0.05 – 0.25 mm | ±0.03 mm | ±0.015 mm | ±10% | Coil (50–15,000m) / Cut |
| 1.01 – 2.50 mm | 0.10 – 0.40 mm | ±0.04 mm | ±0.020 mm | ±10% | Coil (100–15,000m) / 1–6m |
| 2.51 – 5.00 mm | 0.20 – 1.00 mm | ±0.05 mm | ±0.025 mm | ±10% | Coil / 1–6m Straight |
Regional Standard Tolerance Matrices
Scope & Engineering Application: N. America & Global — Small-diameter seamless & welded austenitic stainless steel tubing for general & instrumentation service
| Nominal Size (OD) | WT (mm / in) | ASTM A632 Standard Tol. | Precision Cold-Drawn Tol. | WT Tol. |
|---|---|---|---|---|
| 0.50 mm (0.020") | 0.15 mm (0.006") | +0.05mm / -0.00mm | ±0.015 mm (±0.0006") | ±10.0% |
| 1.00 mm (0.039") | 0.20 mm (0.008") | +0.05mm / -0.00mm | ±0.015 mm (±0.0006") | ±10.0% |
| 1.59 mm (1/16") | 0.25 mm (0.010") | +0.05mm / -0.00mm | ±0.020 mm (±0.0008") | ±10.0% |
| 2.38 mm (3/32") | 0.35 mm (0.014") | +0.08mm / -0.00mm | ±0.020 mm (±0.0008") | ±10.0% |
| 3.18 mm (1/8") | 0.50 mm (0.020") | +0.08mm / -0.00mm | ±0.025 mm (±0.0010") | ±10.0% |
| 4.76 mm (3/16") | 0.71 mm (0.028") | +0.10mm / -0.00mm | ±0.030 mm (±0.0012") | ±10.0% |
| 6.35 mm (1/4") | 0.89 mm (0.035") | +0.10mm / -0.00mm | ±0.030 mm (±0.0012") | ±10.0% |
Per ASTM A632 Table 3: standard OD tolerance is one-directional (+plus only, tube may be oversize but not undersize). Wall thickness allowance is ±10% (Section 9.1). For analytical instrumentation, chromatography, and sensor sheaths, TeCarve multi-pass precision cold drawing achieves symmetrical tight precision limits down to ±0.015mm.
Scope & Engineering Application: Europe & International — Stainless steel precision capillary & instrumentation tubing (EN 10216-5, Classes D4/T4 & Precision D4+)
| Nominal OD (mm) | WT (mm) | Class D4 Standard Tol. | Precision Class D4+ | WT Allowance (T4/T3) |
|---|---|---|---|---|
| 0.50 | 0.12 | ±0.05 mm | ±0.015 mm | ±7.5% (T4 min ±0.05mm) |
| 1.00 | 0.20 | ±0.05 mm | ±0.020 mm | ±7.5% (T4 min ±0.05mm) |
| 1.60 | 0.25 | ±0.05 mm | ±0.020 mm | ±7.5% (T4 min ±0.05mm) |
| 2.00 | 0.30 | ±0.05 mm | ±0.020 mm | ±10.0% (T3 min ±0.10mm) |
| 3.00 | 0.50 | ±0.05 mm | ±0.025 mm | ±10.0% (T3) |
| 4.00 | 0.50 | ±0.05 mm | ±0.025 mm | ±10.0% (T3) |
| 5.00 | 0.80 | ±0.05 mm | ±0.030 mm | ±10.0% (T3) |
| 6.00 | 1.00 | ±0.05 mm | ±0.030 mm | ±10.0% (T3) |
Conforms to EN ISO 1127 Class D4 (OD ±0.5%, min ±0.05mm) and Class T4 (±7.5%, min ±0.05mm) / T3 (±10%). Precision Class D4+ is manufactured via multi-cycle precision cold sink drawing with intermediate bright annealing.
Scope & Engineering Application: Germany & Central Europe — Seamless circular precision cold-drawn stainless steel capillary tubes (DIN 17458 / DIN 2391)
| Size Range OD (mm) | WT Range (mm) | Standard Tolerance | High-Precision Class | Wall Allowance |
|---|---|---|---|---|
| 0.30 – 1.00 | 0.08 – 0.20 | ±0.03 mm | ±0.015 mm | ±10% |
| 1.01 – 2.00 | 0.15 – 0.35 | ±0.04 mm | ±0.020 mm | ±10% |
| 2.01 – 3.50 | 0.20 – 0.50 | ±0.05 mm | ±0.025 mm | ±10% |
| 3.51 – 5.00 | 0.30 – 0.80 | ±0.06 mm | ±0.025 mm | ±10% |
| 5.01 – 8.00 | 0.50 – 1.00 | ±0.08 mm | ±0.030 mm | ±10% |
Technical delivery conditions per DIN 17458 for high-temperature and instrumentation seamless tubes. High-precision grade complies with tightest DIN 2391 cold-drawn precision limits.
Scope & Engineering Application: Asia-Pacific — Stainless steel small-diameter seamless steel tubes
| Nominal OD (mm) | WT Range (mm) | Normal Grade | High-Precision Grade | Wall Tol. (WT) |
|---|---|---|---|---|
| 0.50 – 1.00 | 0.10 – 0.20 | ±0.030 mm | ±0.015 mm (±0.010mm opt.) | ±10% (min ±0.02mm) |
| 1.01 – 2.00 | 0.15 – 0.30 | ±0.030 mm | ±0.020 mm | ±10% (min ±0.02mm) |
| 2.01 – 3.00 | 0.20 – 0.50 | ±0.040 mm | ±0.020 mm | ±10% (min ±0.02mm) |
| 3.01 – 5.00 | 0.25 – 0.80 | ±0.040 mm | ±0.025 mm | ±10% |
| 5.01 – 8.00 | 0.40 – 1.00 | ±0.050 mm | ±0.030 mm | ±10% |
| 8.01 – 10.00 | 0.50 – 1.50 | ±0.060 mm | ±0.040 mm | ±10% |
Tolerances conform strictly to GB/T 3090-2020 Table 1 and Table 2. High-precision grade delivers ±0.015mm OD accuracy on micro-bore capillary sizes, with 100% eddy current testing.
Surface Finish & Thermal Delivery States
Solution heat-treated followed by acid pickling to remove oxide scale and restore full corrosion resistance. Silvery-matte finish (Ra ~ 1.5–2.5 μm). Recommended for general chemical processing, fluid sampling lines, and structural micro-tubing.
Precision outer-diameter mechanical centerless grinding and belt polishing (180 to 400 grit) to enhance OD concentricity and ease of cleaning (OD Ra ≤ 0.4–0.8 μm). Suited for accessible analytical housings and sensor protective sheaths.
Heat-treated in a closed continuous furnace under pure hydrogen (dew point < -50°C) protective atmosphere. Zero oxidation leaves a mirror-bright, scale-free finish on both ID and OD (Ra ≤ 0.2–0.4 μm) with superior micro-cleanliness for GC, HPLC, and pressure sensors.
Precision Burr-Free Cutting & End-Finish Processes
Small-diameter capillary tubing requires specialized cutting to prevent internal lumen collapse, wall necking, and metal burrs. TeCarve employs precision cut-off technologies tailored to project specifications:
Contactless electrochemical dissolution cut. Leaves 100% burr-free ends on both ID and OD, zero mechanical deformation or pinching, and zero heat-affected zone (HAZ). Ideal for chromatography sample probes and microfluidics.
Thin diamond/resin slicing disc followed by automated rotary mechanical edge deburring and high-frequency multi-stage ultrasonic wash. Keeps the internal diameter clear for sensor and refrigeration lines.
Focused fiber laser with kerf width < 0.02 mm, providing perpendicular square cuts (≤ 0.5°) with minimal thermal transfer. Suited for short precision cut sleeves (10 mm to 500 mm).
Coiled & Straight Tube Packaging Standards
- Continuous Lengths: Unbroken continuous coils in any length up to 15,000 m and beyond, eliminating field weld joints and leak hazards.
- Spooling Formats: Free-coiled level-wound coils (OD 300–600 mm) or wound on heavy-duty plastic/wooden spools to prevent kinking or ovality distortion during automated uncoiling.
- Bore Protection: Ends plugged with airtight polyethylene push-in caps; internal bore dried and sealed under positive-pressure dry nitrogen.
- Moisture Barrier: Vacuum PVC shrink wrap + Vapor Corrosion Inhibitor (VCI) anti-rust paper + desiccant packs in seaworthy wooden crates.
- Cut Lengths: Standard 1 m to 6 m; custom precision micro-cut lengths from 10 mm to 3,000 mm (length tolerance ±0.2 mm to ±1.0 mm).
- Protective Sleeving: Bundled in polyethylene sleeve tubing, inserted into rigid protective PVC conduits or heavy-wall export plywood cases.
- Handling Integrity: Internal foam cushioning and reinforced strapping prevent tube bending, scuffing, or vibration damage during multi-modal transit.
- Marking & Traceability: Color-coded end tagging, heat-number barcoding, and EN 10204 3.1 MTC included in weatherproof packing slips.
TeCarve operates under certified ISO 9001:2015, ISO 14001:2015, and ISO 45001:2018 management systems. Every capillary tubing order is supplied with an authentic EN 10204 3.1 Mill Test Certificate (MTC) verifying heat chemistry, mechanical tensile/yield data, dimensional inspection, and 100% eddy current / pressure testing results. (Note: TeCarve supplies high-purity raw tubing conforming to ASTM A632, EN ISO 1127, DIN 17458, and GB/T 3090; final device-level clearances such as ISO 13485 or FDA 510(k) establishment registrations remain the responsibility of the medical device manufacturer).
Get Your Precision Capillary Tube Quote
Sourcing precision capillary tubing for analytical instruments, chromatography columns, temperature sensors, or micro-fluidic circuits? Contact our precision engineering desk for custom tight-precision OD (down to 0.10 mm), ID calibration, and prototype evaluation orders.
Tight dimensional accuracy on OD and ID (down to ±0.01 mm) with smooth, burr-free rotary electrolytic cutting.
Precision capillary sample coils or straight cuts available for fluid-flow calibration, sensor fit, and crimp testing.
Standard capillary tube trial orders start from 100 pieces per size/spec. Custom precision requirements are reviewed before production MOQ is confirmed.
recording material composition (316L, 304), temper conditions (soft annealed or hard drawn), and pressure/leak test documentation.
Standards
→ Scroll right for full chemistry & mechanical data
| Grade | US (UNS) | EN (W.Nr.) | Japan (JIS) | China (GB/T) | C % (Max) | Si % (Max) | Mn % (Max) | P % (Max) | S % (Max) | Cr % | Ni % | Mo % | Tensile σb (Min.) | Yield σ0.2 (Min.) | Elongation (Min.) | Hardness (Max) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 304 | S30400 | 1.4301 | SUS304 | 06Cr19Ni10 | 0.08 | 0.75 | 2.00 | 0.045 | 0.030 | 18.0-20.0 | 8.0-11.0 | — | 515 MPa (75 ksi) | 205 MPa (30 ksi) | 35% | ≤92 HRB / ≤215 HV |
| 304L | S30403 | 1.4307 | SUS304L | 022Cr19Ni10 | 0.030 | 0.75 | 2.00 | 0.045 | 0.030 | 18.0-20.0 | 8.0-12.0 | — | 485 MPa (70 ksi) | 170 MPa (25 ksi) | 35% | ≤92 HRB / ≤215 HV |
| 316 | S31600 | 1.4401 | SUS316 | 06Cr17Ni12Mo2 | 0.08 | 0.75 | 2.00 | 0.045 | 0.030 | 16.0-18.0 | 10.0-14.0 | 2.0-3.0 | 515 MPa (75 ksi) | 205 MPa (30 ksi) | 35% | ≤95 HRB / ≤215 HV |
| 316L | S31603 | 1.4404 | SUS316L | 022Cr17Ni12Mo2 | 0.030 | 0.75 | 2.00 | 0.045 | 0.030 | 16.0-18.0 | 10.0-14.0 | 2.0-3.0 | 485 MPa (70 ksi) | 170 MPa (25 ksi) | 35% | ≤95 HRB / ≤215 HV |
| 321 | S32100 | 1.4541 | SUS321 | 06Cr18Ni11Ti | 0.08 | 0.75 | 2.00 | 0.045 | 0.030 | 17.0-19.0 | 9.0-12.0 | — | 515 MPa (75 ksi) | 205 MPa (30 ksi) | 35% | ≤95 HRB / ≤215 HV |
| 310S | S31008 | 1.4845 | SUS310S | 06Cr25Ni20 | 0.08 | 1.50 | 2.00 | 0.045 | 0.030 | 24.0-26.0 | 19.0-22.0 | — | 515 MPa (75 ksi) | 205 MPa (30 ksi) | 35% | ≤95 HRB / ≤215 HV |
| 317L | S31703 | 1.4438 | SUS317L | 022Cr19Ni13Mo3 | 0.030 | 0.75 | 2.00 | 0.045 | 0.030 | 18.0-20.0 | 11.0-15.0 | 3.0-4.0 | 515 MPa (75 ksi) | 205 MPa (30 ksi) | 35% | ≤95 HRB / ≤215 HV |
| 430 | S43000 | 1.4016 | SUS430 | 10Cr17 | 0.12 | 1.00 | 1.00 | 0.040 | 0.030 | 16.0-18.0 | — | — | 450 MPa (65 ksi) | 205 MPa (30 ksi) | 22% | ≤89 HRB / ≤200 HV |
| 904L* | N08904 | 1.4539 | N/A | 015Cr20Ni18Mo6CuN* | 0.020 | 1.00 | 2.00 | 0.045 | 0.035 | 19.0-23.0 | 23.0-28.0 | 4.0-5.0 | 490 MPa (71 ksi) | 215 MPa (31 ksi) | 35% | ≤90 HRB / ≤200 HV |
| 2205 Duplex* | S32205 | 1.4462 | SUS329J3L* | 022Cr23Ni5Mo3N* | 0.030 | 1.00 | 2.00 | 0.030 | 0.020 | 22.0-23.0 | 4.5-6.5 | 3.0-3.5 | 655 MPa (95 ksi) | 450 MPa (65 ksi) | 25% | ≤31 HRC / ≤293 HB |
- Standards Conformance: ASTM A632 · EN 10216-5 · JIS G4305/G3459 · GB/T 18457
- Delivery Condition: Solution Annealed & Pickled (AP) / Bright Annealed (BA) / Polished, or as requested.
- Mill Test Certificate: 100% full material traceability with EN 10204 3.1 MTC provided with every shipment.
- Cross-Reference Note: 2205 duplex and 904L JIS/GB cross-reference figures are compiled from secondary industry sources — please confirm exact specification and heat-specific mill test certificate with TeCarve for critical applications.
Features
• Micro-diameter precision
• Clean, smooth inner and outer surfaces
• Excellent corrosion resistance
• High-pressure resistance and flexibility
• Medical catheters and instruments
• Laboratory and analytical equipment
• Temperature and pressure sensors
• Microfluidic and aerospace systems
Applications
Precision needle tubing, catheter components & surgical instruments, biopsy guide cannulas, blood collection needles, and endoscopic fluid transfer channels with burr-free cut ends.
Protective sheaths for RTD (Pt100/Pt1000) temperature sensors, mineral insulated thermocouple wells, pressure transducer capillary lines, and thermistor probes requiring rapid thermal response and hermetic seal integrity.
Miniature pneumatic and hydraulic signal impulse lines, automated chemical sampling loops, pilot valve pressure leads, and automated flow-metering capillary connections in chemical and processing plants.
Refrigerant expansion throttling capillary tubes, thermostatic expansion valve (TXV) sensing bulbs, cryocooler capillary loops, and temperature controller sensor lines with uniform ID cross-sections.
Common-rail diesel pressure sensor lines, brake hydraulic micro-tubing, oxygen sensor lead guides, and engine exhaust temperature sensor protective sheaths built for high vibration and thermal cycling.
High-performance liquid chromatography (HPLC) and gas chromatography (GC) capillary columns, mass spectrometer sample introduction probes, and high-purity carrier gas micro-manifolds.
For a more rigid, application-specific precision option, compare this capillary range with our Stainless Steel Needle Tube.
Unsure whether your application requires standard capillary or cannula-gauge tubing? Read our engineering comparison in the Capillary Tube vs Needle Tube Selection Guide. Preparing an RFQ? Use our capillary tube specification checklist to define OD/ID, tolerance, temper, finish and cutting.
For precision capillary-tube sourcing, use our factory-audit and quality-control checklist to review equipment, dimensional inspection, material traceability, and supporting documents before production.
Quality Control
• 100% dimensional and geometry verification
• Surface cleanliness and micro-deburring inspections
• Non-destructive eddy current testing
• ISO and third-party certifications available
packaging
PVC Wrapping
& End Caps
Custom Barcoding
& Labeling
Anti-Corrosion
& Moisture Protection
Seaworthy Wooden Cases & Pallets
Capillary Tube Production & Quality Photos
Real product, inspection, packaging and loading photos.
Tailored Solutions, Timely Fulfillment
CUSTOMIZATION
& DELIVERY
Flexible Custom Manufacturing
We tailor stainless steel capillary tube by micro-diameter, wall thickness, coil or cut length, grade, polished or bright-annealed finish, tube type, and the dimensional specifications required by the application.
Low MOQ & Rapid Prototyping
Standard capillary tube trial orders start from 100 pieces per size/spec. For micro-bore, ultra-thin-wall, tight-tolerance, custom-cut, or special-finish tubing, prototype quantities and production MOQ are confirmed after technical review.
Optimized Lead Time
In-stock standard sizes ship within 7–10 days. Custom specifications typically ship within 10–25 days after deposit, depending on order volume, dimensions, and surface finish. The full cycle—from inquiry and drawing confirmation through sampling, production, inspection, and dispatch—typically takes 33–55 days for custom items.
Global Logistics & On-Time Delivery
For capillary tube shipments worldwide, anti-corrosion and moisture protection is emphasized alongside custom barcoding and labeling for precise package identification.
How your order is made, checked and shipped
Tube forming at the partner factory
Heat treatment (annealing)
Dimensional inspection
Alloy verification with a handheld analyzer
Export packing
Container loading
What Global Buyers Say About TeCarve Tubing
“I've received the goods and everything is fine.”
“The goods already send to customers. I am waiting for the next order from them.”
“…there is no need of inspection this time… I trust in your product.”
Frequently Asked Questions
What is stainless steel capillary tube used for?
Stainless steel capillary tube is used in medical devices (catheters, endoscopes, surgical tools), scientific instruments, HVAC refrigeration systems, automotive sensors, and analytical laboratory equipment where precise small-diameter tubing with tight precision limits is required.
What is the OD range for stainless steel capillary tube?
TeCarve supplies stainless steel capillary tubes with outer diameter from 0.1 mm to 5.0 mm and wall thickness from 0.03 mm to 1.0 mm. OD tolerances of ±0.01 mm are achievable for medical and scientific precision applications.
What grades of stainless steel are used for capillary tubes?
Common grades are 304, 316L, 316, and 321. Grade 316L is preferred for medical and pharmaceutical use due to its biocompatibility and resistance to sterilization agents. Electropolished inner and outer surfaces are available for cleanroom and medical applications.
What is the maximum continuous length for capillary tube?
Straight capillary tubes are available up to 6 m. Coiled capillary tube can be supplied in continuous coils exceeding 15,000 m, eliminating joints for applications requiring long, leak-free runs such as refrigeration and instrumentation.
What documentation is available for medical capillary tube projects?
Documentation requirements depend on the intended application and order specification. Contact TeCarve to confirm which material certificates, inspection records, and traceability documents can be supplied for your project.
What is the minimum order quantity (MOQ) for stainless steel capillary tube?
Standard capillary tube trial orders start from 100 pieces per size/spec. For micro-bore, ultra-thin-wall, tight-tolerance, custom-cut, or special-finish tubing, prototype quantities and production MOQ are confirmed after technical review. In-stock standard sizes ship within 7–10 days.
Can TeCarve provide clean bore capillary tubing?
Yes. We supply capillary tubing with ASTM A632 S3 clean bore on request, suitable for instrumentation and chromatography fluid delivery.
What dimensional tolerances can TeCarve achieve on capillary tubes?
We supply capillary tubes with outer diameter tolerance from ±0.05 mm according to customer drawing and order requirements.
Can capillary tubing be supplied in precision straight cuts or continuous coils?
Yes. We supply capillary tubing in precision straight cut lengths as well as continuous coils, packaged with protective end caps in seaworthy wooden cases.
Contact TeCarve