描述

304 Stainless Steel Capillary Tube – 33.00mm OD x 30.00mm ID x 1.50mm Wall

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I. Detailed Product Specifications

Parameter	Value	Tolerance / Standard
Material Grade	304 Stainless Steel (UNS S30400)	ASTM A269 / A213
Outer Diameter (OD)	33.00 mm	±0.01 mm (ISO 2768-f)
Inner Diameter (ID)	30.00 mm	±0.01 mm
Wall Thickness (WT)	1.50 mm	±0.01 mm
Wall-to-OD Ratio	4.5%	Thin wall design
Inner Cross-Section Area	706.8578 mm²	Flow capacity: Excellent
Available Length	Custom cut (up to 2500 mm)	±0.01 mm (laser precision)
Surface Finish	Bright Annealed / Electropolished	Ra ≤ 0.4 μm (optional Ra ≤ 0.2 μm)
Straightness	≤ 0.5 mm / 1000 mm	ASTM A269
End Finish	Burr-free, square cut	≤ 0.05 mm end burr
Packaging	Plastic capped / Vacuum sealed	Anti-contamination

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II. Chemical Composition (Weight %)

Element	Percentage (%)	Description
Carbon (C)	≤ 0.08	Standard carbon content
Chromium (Cr)	18.0 – 20.0	Primary corrosion resistance
Nickel (Ni)	8.0 – 10.5	Austenitic structure stabilizer
Manganese (Mn)	≤ 2.00	Deoxidizer and strength enhancer
Silicon (Si)	≤ 1.00	Improves scaling resistance
Phosphorus (P)	≤ 0.045	Controlled for ductility
Sulfur (S)	≤ 0.030	Controlled for machinability
Nitrogen (N)	≤ 0.10	Strengthens austenitic structure
Iron (Fe)	Balance	Base material

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III. Mechanical Properties

Property	Value	Unit	Test Standard	Notes
Tensile Strength	515 – 690	MPa	ASTM E8	Measured at room temperature
Yield Strength (0.2% Offset)	≥ 205	MPa	ASTM E8	Cold drawn condition
Elongation at Break	≥ 35 – 45	%	ASTM E8	50 mm gauge length
Hardness	≤ 92	HRB	ASTM E18	Rockwell B scale
Modulus of Elasticity	193 – 200	GPa	ASTM E111	Typical for austenitic SS
Poisson’s Ratio	0.27 – 0.30	–	ASTM E132	–
Density	7.90 – 8.00	g/cm³	ASTM A269	At 20°C
Thermal Expansion	17.3	μm/m·°C	ASTM E831	20°C – 100°C

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IV. Dimensional Tolerance & Quality Assurance

OD Range	Inspection Frequency	Inspection Method
0.25 mm – 0.50 mm	100%	Laser micrometer
0.50 mm – 1.00 mm	100%	Laser micrometer
1.00 mm – 3.00 mm	100%	Digital caliper + micrometer
3.00 mm – 6.00 mm	Batch ±10%	Digital caliper

All tubes undergo 100% dimensional verification with traceable calibration. Each batch includes chemical and mechanical certification upon request.

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V. Surface Finish Options

Finish Type	Ra Value	Application	Process
Bright Annealed	Ra ≤ 0.4 μm	General purpose, medical	Annealing in controlled atmosphere
Electropolished	Ra ≤ 0.2 μm	Pharmaceutical, semiconductor	Electrochemical polishing
Mechanical Polish	Ra ≤ 0.3 μm	Industrial, automotive	Mechanical buffing
Passivated	As-drawn	Corrosion critical	Nitric acid passivation per ASTM A967

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VI. Key Features & Advantages

Feature	Specification	Benefit to Customer
Ultra-Fine OD	33.00 mm outer diameter	Fits into compact assemblies and micro-devices
Thin Wall Design	1.50 mm wall thickness	Reduces weight while maintaining structural integrity
High Precision ID	30.00 mm ±0.01 mm inner bore	Consistent fluid flow with minimal pressure variation
Corrosion Resistance	Excellent in oxidizing environments	Longer service life in harsh media
Biocompatibility	ISO 10993 compliant	Suitable for implant-grade and surgical instruments
Burr-Free Cutting	Laser / precision cut ≤ 0.05 mm burr	No secondary deburring required
Lot Traceability	Full material traceability	Complete QA documentation available
Custom Lengths	Cut to exact specification	Reduces waste and assembly time

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VII. Typical Applications & Industry Use Cases

Industry	Application	Why This Product Excels
Medical Devices	Hypodermic tubing, stent delivery, catheter shafts	Precision ID ensures accurate fluid delivery; biocompatible surface minimizes tissue reaction
Analytical Instruments	HPLC columns, gas chromatography, microfluidics	Smooth ID reduces sample carryover; tight ID tolerance ensures reproducible results
Pharmaceutical Manufacturing	Dispensing tips, sampling needles, transfer lines	Non-reactive 316L surface maintains sample purity; electropolished option available for CIP/SIP
Semiconductor	Gas delivery lines, sensor probes, etching nozzles	Ultra-clean surface; electropolished finish minimizes particle entrapment
Aerospace & Defense	Hydraulic sensing lines, fuel injection, coolant paths	High strength-to-weight ratio; excellent fatigue resistance under vibration
Automotive	Fuel injector nozzles, EGR systems, brake sensing lines	Consistent ID ensures predictable flow rates; corrosion resistant to fuels and coolants
Chemical Processing	Catalyst injection, sampling ports, heat exchanger tubes	304 SS resists a wide range of chemicals at elevated temperatures
Research & Development	Lab-on-a-chip, micro-reactors, experimental setups	Custom dimensions available; small batch quantities supported

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VIII. CNC Machining & Fabrication Capabilities

Fabrication Service	Capability	Tolerance
Precision Cutting	Laser cutting, abrasive cutting	±0.01 mm
End Forming	Swaging, flaring, reducing, expanding	±0.02 mm
Bending	CNC mandrel bending up to 180°	±0.5°
Drilling / Perforation	Laser micro-drilling (0.05 mm min.)	±0.005 mm
Welding	Orbital TIG, laser welding	Full penetration, no internal flash
Marking	Laser engraving, chemical etching	Permanent, legible
Cleaning	Ultrasonic cleaning, passivation	Per ASTM A967 / ISO 13485

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IX. Available Packaging & Shipping Options

Packaging Type	Description	Best For
Bulk Pack	Polybag + carton box	Large quantity orders
Individual Sleeve	Heat-sealed PE sleeve per tube	Medical / cleanroom applications
Vacuum Sealed	Vacuum pack with desiccant	Long-term storage, sensitive components
Custom Kitting	Pre-sorted by length per kit	Assembly line ready

Shipping: Worldwide via DHL, FedEx, UPS, or sea freight. Typical lead time: 7–15 working days for standard orders.

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X. Comparison: 304 vs Other Common Grades

Property	304 SS (This Product)	304L SS	316 SS	321 SS
Corrosion Resistance	★★★★★	★★★★	★★★★★	★★★★
Weldability	★★★★★	★★★★★	★★★★	★★★★
Machinability	★★★★	★★★★	★★★	★★★
Cost Efficiency	★★★★★	★★★★★	★★★	★★★
High Temp Performance	★★★	★★★	★★★★	★★★★★
ID Surface Finish	Ra ≤ 0.4 μm	Ra ≤ 0.6 μm	Ra ≤ 0.4 μm	Ra ≤ 0.6 μm

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XI. Quality Control & Certifications

Inspection Stage	Parameter	Method	Frequency	Standard
Incoming	Material certification	Mill test report review	100% per lot	EN 10204 3.1
In-Process	OD / ID / WT	Laser micrometer	Continuous	ISO 2768
Final	Full dimensional check	Vision + contact measurement	100%	ISO 13485
Surface	Defects, burrs, contamination	10× optical inspection	100%	ASTM A269
Mechanical	Tensile, hardness	Universal tester	Per lot	ASTM E8 / E18
Chemical	Composition verification	OES / ICP	Per lot	ASTM A751
Pressure	Leak test	Air / hydrostatic	Per request	ASME B31.3

We provide Certificates of Compliance (CoC) with every order and Material Test Reports (MTR) upon request.

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XII. Why Choose Capillary Tubing Network?

Advantage	What It Means For You
15+ Years Experience	Deep expertise in micro-tubing manufacturing and precision cutting
ISO-Compliant Facility	Certified processes ensure consistent quality from batch to batch
Short Lead Times	Standard orders ship within 7–15 working days
Custom Manufacturing	OEM/ODM: we produce to your exact drawing and specification
Technical Support	Engineers available to help select the optimal grade and dimension
Global Shipping	Reliable logistics partners serving North America, Europe, and Asia

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Product SKU: CT-304-OD3300-ID3000-WT150 — Last Updated: 2026-05-25

Tags: seamless stainless steel capillary tube, precision stainless steel tube, 304 capillary tube, 33.00mm OD tube, precision micro tubing, thin wall stainless steel tube, 304 seamless precision tube