ASTM A269 TP304 Stainless Steel Instrumentation Tubing

‌ASTM A269 TP304 stainless steel instrumentation tube‌ is an austenitic stainless steel tube made from TP304 (UNS S30400) material, specifically designed for fluid transmission in instrumentation and control systems. It is widely used in ‌chemical processing, power generation, pharmaceuticals, food processing, and heat exchangers‌ where high cleanliness and reliability are required for instrumentation piping systems.

 

According to the ASTM A269/A269M-25 standard, ‌ASTM A269 TP304 tubes‌ must be supplied in the ‌solution annealed condition‌, with an annealing temperature not lower than ‌1040°C‌, followed by water quenching or rapid cooling to ensure a uniform microstructure and excellent intergranular corrosion resistance. The required mechanical properties include tensile strength ≥ ‌515 MPa‌, yield strength ≥ ‌205 MPa‌, and elongation ≥ ‌35%‌, meeting the demands of high-pressure and high cyclic stress service conditions.

 

GNEE supplies stainless steel instrument tubing conforming to ASTM A269 TP304 standards, with common outer diameters ranging from 6-48 mm and wall thicknesses from 0.5-3.0 mm. Lengths are available in 3-meter, 6-meter, or custom lengths upon request. Surface treatments are typically bright annealing (BA) or pickling, resulting in smooth inner and outer walls with low roughness, facilitating cleaning and sterilization, and making them suitable for conveying high-purity fluids.

ASTM A269 TP304 stainless steel tubes specification

Item	BA Stainless Steel Seamless Tube/Pipe
Standard	ASTM A269
Material	300 Series:304,304L,304H,316,316L,316Ti
Surface	Polishing,annealing,pickling,bright
Shape	Round Pipe/Tube
Type	cold rolled
Application	Hydraulic Tubes & Instrumentation Tubes
size	Length	5.8m/6m/ 11.8m/ 12m or Customized
	Outer diameter	6mm-114mm
Delivery time	Within 5-30 days after receiving the prepaid
Package	Standard export seaworthy package,or as required

 

ASTM A269 TP304 Chemical Composition

Grade		C	Mn	Si	P	S	Cr	Mo	Ni	N
304	min.	-	-	-	-	-	18.0	-	8.0	-
	max.	0.08	2.0	0.75	0.045	0.030	20.0		10.5	0.10

 

ASTM A269 TP304 Mechanical Properties (Annealed Condition)

Property	ASTM A269 Requirement	Typical Value
Tensile Strength	≥ 515 MPa (75 ksi)	550 MPa
Yield Strength (0.2% Offset)	≥ 205 MPa (30 ksi)	240 MPa
Elongation (% in 50mm)	≥ 35%	55%
Hardness (Rockwell B)	≤ 90 HRB	80 HRB

 

 Standard Tolerances for ASTM A269 TP304 Tubing

Dimension	Seamless Tube Tolerance	Welded Tube Tolerance
OD (mm)	±0.10 mm (≤25.4mm OD) ±0.38 mm (>25.4mm OD)	±0.13 mm (≤25.4mm OD) ±0.25 mm (>25.4mm OD)
Wall Thickness	±10%	±10%
Straightness	3.2 mm/m max	3.2 mm/m max
Cut Length	+3.2 mm / -0 mm	+3.2 mm / -0 mm

 

 TP304 Material pipe Applications

Industry	Critical Applications
Medical Devices	Hypodermic needles, surgical instruments, implantable device components
Pharmaceutical	Bioreactor transfer lines, CIP/SIP systems, sterile fluid handling
Food & Beverage	Dairy processing pipes, brewery transfer lines, FDA-compliant fittings
Chemical Processing	Heat exchanger tubes, corrosive fluid transfer, sampling systems
Instrumentation	Pressure gauge tubing, chromatography columns, sensor housings

 

How to Choose Between TP304 and TP316L Instrument Tubing?

TP304 is more cost-effective and suitable for general corrosive environments and indoor, non-salt spray environments. TP316L contains 2-3% molybdenum (Mo), providing stronger resistance to chloride pitting corrosion. If the operating conditions are in chemical plants, near-shore docks, or involve contact with acidic media, TP316L must be selected.

 

GNEE instrument tubing typically undergoes the following rigorous tests before leaving the factory:
Hydrostatic Test: Ensures no leakage under high pressure.
Eddy Current Test: 100% non-destructive testing for internal pipe wall defects.
Hardness Test: Ensures ease of bending and processing.
Air Tightness Test: Especially for BA-grade laboratory tubing.

 

Packaging:

GNEE supplies TP304 instrument tubing with a hardness controlled to ≤80HRB and an outer diameter tolerance accurate to ±0.05mm. Each tubing is sealed after being purged with high-purity nitrogen and individually packaged in a 150μm PE bag with reinforced end plugs for protection. The outer packaging uses a pressure-resistant, fumigation-free wooden crate reinforced with U-groove channels to ensure that the BA-grade surface with Ra≤0.4μm remains scratch-free and contaminated during long-distance transportation, achieving an overall delivery qualification rate of 99.9%.