Stainless Steel 304 Instrumentation Tubes Specifications
This table shows the main details of Stainless Steel 304 instrumentation tubes, such as standards, sizes, wall thickness, finishes, forms, and end types for industrial use.
| Parameter | Details |
|---|---|
| Standards | ASTM A269, ASTM A213 / ASME SA-213, ASTM A249 / ASME SA-249 |
| OD Range | 1/8" (3.18 mm) to 1-1/2" (38.10 mm) |
| Wall Thickness | 0.028" to 0.083" |
| Length | 20 feet (6 metres) standard; coils and cut-to-length on request |
| Forms | Seamless (cold drawn), Welded |
| Finish | Annealed & Pickled (AP), Bright Annealed (BA), Mill Finish (MF), Polished (320-grit OD) |
| End Type | Plain end, deburred |
Dimensional Tolerances
For ASTM A269 TP304 tubes, the tolerances for outside diameter (OD) and wall thickness need to align with the tables outlined in ASTM A269. These tolerances will shift depending on the tube's OD and how it was made. Maintaining these precise tolerances is key to achieving a leak-proof seal when using compression fittings.
| OD Range | OD Tolerance | Wall Tolerance |
|---|---|---|
| ≤ 0.500" | ± 0.005" | ± 10% |
| 0.500"-1.500" | ± 0.005" | ± 10% |
| 1.500"-3.500" | ± 0.010" | ± 10% |
Stainless Steel 304 Instrumentation Tube Sizes
SS 304 instrumentation tubes come in outside diameters from 1/8” (3.18 mm) to 1-1/2” (38.10 mm) and wall thicknesses from 0.028” to 0.083”. The charts below show available imperial and metric sizes. Standard length is 20 feet (6 metres), with coils and cut-to-length pieces available on request.
Sizes and Weight Chart
The chart below covers OD and wall thickness pairings stocked by Sachiya Steel International.
| OD (inch) | OD (mm) | Common Wall Thicknesses (inch) |
|---|---|---|
| 1/8" | 3.18 | 0.028, 0.035 |
| 3/16" | 4.76 | 0.035 |
| 1/4" | 6.35 | 0.028, 0.035, 0.049 |
| 5/16" | 7.94 | 0.035 |
| 3/8" | 9.53 | 0.035, 0.049, 0.065 |
| 1/2" | 12.70 | 0.035, 0.049, 0.065 |
| 5/8" | 15.88 | 0.035, 0.049, 0.065 |
| 3/4" | 19.05 | 0.049, 0.065, 0.083 |
| 1" | 25.40 | 0.049, 0.065 |
| 1-1/4" | 31.75 | 0.065 |
| 1-1/2" | 38.10 | 0.065 |
Metric Instrumentation Tube Sizes
Metric SS 304 instrumentation tubes are available in 6, 8, 10, 12, and 25 mm OD as per client requirements. Common wall thicknesses are 0.89 mm, 1.24 mm, and 1.65 mm.
Stainless Steel 304 Instrumentation Tubes Price
SS 304 instrumentation tubes usually cost about ₹210 to ₹560 per foot (2.50 to 6.70 dollars in global markets), depending on outer diameter, wall thickness and order quantity. Seamless tubes are about 15% to 30% more expensive than welded tubes.
Sachiya Steel International provides competitive FOB Mumbai and CIF export prices based on project needs.
Chemical Composition of Stainless Steel 304 Instrumentation Tubes
The table below shows the full chemical composition of TP304 tubing.
SS 304 instrumentation tubes made to ASTM A213 / ASME SA-213 contain about 18-20% chromium and 8-11% nickel, with carbon limited to a maximum of 0.08%.
Mechanical Properties of 304 Stainless Steel Instrumentation Tubes
The following properties are suitable for demanding instrument tubing installations.
According to ASTM A213, 304 instrumentation tubes are required to have a minimum tensile strength of 75 ksi (515 MPa) and a yield strength of 30 ksi (205 MPa).
| Property | Value | Unit |
|---|---|---|
| Tensile Strength (min) | 75 / 515 | ksi / MPa |
| Yield Strength, 0.2% Offset (min) | 30 / 205 | ksi / MPa |
| Elongation (min, in 2") | 35 | % |
| Hardness (max) | 90 | HRB |
Stainless Steel 304 Instrumentation Tubes Equivalent Grades
This table shows equivalent grades for this alloy in major international standards.
Stainless Steel 304 instrumentation tubes are widely used in hydraulic and pneumatic systems because they are easy to form and resist atmospheric corrosion.
| Standard / Region | Designation |
|---|---|
| USA | UNS S30400 |
| Japan (JIS) | SUS 304 |
| China (GB) | 06Cr19Ni10 (formerly 0Cr18Ni9) |
| UK (BS) | 304S31 |
| Sweden (Trade Name) | R304 / Sandvik 18.8.LR |
Stainless Steel 304 Instrumentation Tubes Industrial Applications
SS 304 instrumentation tubes are used for process instrumentation, hydraulic lines, chemical injection, and sampling in four major industries.
Oil & Gas
Refineries and offshore platforms use SS tubes for instrumentation runs; these tubes are applied to pressure transmitter impulse lines, analyser sample transport, and pneumatic signal connections.
Chemical Processing
AISI 304 instrument tubes carry process samples to connect gauge panels, withstanding dilute organic acids, alkalis and steam condensate.
Power Generation
Thermal power stations rely on SS 304 instrumentation tubing for boiler drum level sensing, steam pressure monitoring and flue gas sampling.
Food & Beverage
Dairy, brewing and bottling lines use bright annealed 304 instrumentation tubes for CIP system connections and sanitary gauge hookups per ASTM A270.
Stainless Steel 304 vs Stainless Steel 316 Instrumentation Tubes
SS 304 instrumentation tubes are a more economical option when exposure to chlorides is low. SS 316 has 2-3% molybdenum, which gives it better resistance to pitting in marine and salty (brine) environments.
| Parameter | SS 304 Instrumentation Tubes | SS 316 Instrumentation Tubes |
|---|---|---|
| Key Alloying Elements | 18-20% Cr, 8-10.5% Ni | 16-18% Cr, 10-14% Ni, 2-3% Mo |
| Corrosion Resistance | Good in general environments | Superior, especially in chloride environments |
| Pitting Resistance | Moderate | High (due to Mo addition) |
| Chloride Stress Corrosion Cracking | Susceptible in chloride conditions | Improved resistance, but not fully immune |
| Marine / Coastal Use | Not recommended | Highly recommended |
| Chemical Processing | Suitable for mild chemicals | Better for aggressive chemicals and chlorides |
| Temperature Resistance | Good up to ~870°C (intermittent) | Similar, slightly better in corrosive high-temp environments |
| Weldability | Excellent | Excellent |
| Cost | Lower | Higher (typically 20-40% more than 304) |
Shipping & Packaging
Heavy-duty wooden boxes Packing
We strictly follow seaworthy export handling standards to protect SS 304 instrumentation tubes from transit damage, moisture ingress, and surface contamination during long-distance dispatch.
- Heavy-duty wooden boxes with moisture barrier lining
- HDPE stretch film wrapping on all bundles
- Plastic end caps on threaded and plain-end pipes
- Silica gel desiccants to minimize moisture exposure
- ISPM-15 fumigated wooden packaging for export
Pipe Bundle Yard Staging
Container End-Cap Protection
Wrapped Export-Ready Bundles
We Export Worldwide
Sachiya Steel International supplies stainless steel products to major industrial markets across North America, Europe, the Middle East, Asia and Africa with export-ready documentation and logistics support.
USA
Canada
Germany
UK
Italy
France
Australia
South Korea
Indonesia
Vietnam
Singapore
Malaysia
Taiwan
UAE
Saudi Arabia
Qatar
Oman
South Africa
Nigeria
Egypt