Stainless Steel Pipe

Stainless steel pipe is one of the more standardized materials in the building and engineering industries.

Stainless steel pipes

Stainless Steel Seamless Pipes is a hollow steel bar, a large number of pipes used for conveying fluids, such as oil, gas, water, gas, steam,heat exchanger,mechanical machine.

In addition, engaging in bending, torsional strength of the same, lighter, and they are also widely used in the manufacture of mechanical parts and engineering structures.

Steel pipes are long, hollow tubes that are used for a variety of purposes. They are produced by two distinct methods which result in either a welded or seamless pipe. Industrial Metal Supply carries a wide variety of stainless steel pipe products.

Stainless Steel Pipe Applications 

Stainless steel pipe has a wide variety of applications, some of the most prevalent include: 

Also used in producing all kinds of conventional weapons, the barrel, artillery shells and so on...

Material stainless steel grades

Also known as "marine grade" stainless steel due to its increased ability to resist saltwater corrosion compared to type 304. SS316 is often used for building nuclear reprocessing plants.

304/304L Stainless Steel

304 Stainless is a low carbon (0.08% max) version of basic 18-8 also known as 302.

316/316L Stainless Steel

Type 316 is more resistant to atmospheric and other mild environments than Type 304.

310S Stainless Steel

310S Stainless Steel has excellent resistance to oxidation under constant temperatures to 2000°F.

317L Stainless Steel

317L is a molybdenum bearing austenitic chromium nickel steel similar to type 316, except the alloy content in 317L is somewhat higher.

321/321H Stainless Steel

Type 321 is basic type 304 modified by adding titanium in an amount at least 5 times the carbon plus nitrogen contents.

410 Stainless Steel

Type 410 is a martensitic stainless steel which is magnetic, resists corrosion in mild environents and has fairly good ductility.

Duplex 2205 (UNS S31803)

Duplex 2205 (UNS S31803), or Avesta Sheffield 2205 is a ferritic-austenitic stainless steel.

Duplex 2507 (UNS S32750)

Duplex 2507 (UNS S32750) is a super duplex stainless steel with 25% chromium, 4% molybdenum..

DUPLEX UNS S32760

UNS S32760 is described as a super duplex stainless with a microstructure of 50:50 austenite and ferrite.

SA 269

ASTM A269 / A269M Standard Specification for Seamless and Welded Austenitic Stainless Steel Tubing for General Service

SA 249 Stainless Steel

ASME SA 249 Standard Specification for Welded Austenitic Steel Boiler,
Superheater, Heat-Exchanger, and Condenser Tubes.

904L Stainless steel

904L stainless steel consists of chromium, nickel, molybdenum and copper contents, these elements give type 904L stainless steel excellent properties

See the full data for Stainless steel pipes

Stainless steel pipes are used mainly for industrial use, plants, sanitation, heat exchangers, and machine structures.

Normal Standard

Item ASTM A213/A213M ASTM A312/A312M
Grade TP304 TP304L TP304 TP304L
TP316 TP316L TP316 TP316L
TP317 TP317L TP317 TP317L
TP347 TP310S TP347 TP310S
TP309H* TP310H* TP317* TP310H*
  TP321HΔ   TP321HΔ
Yield Strength
σ0.2 (Mpa)
≥170; ≥205 ≥170; ≥205
Tensile Strength
σb (Mpa)
≥485 ≥515 ≥485; ≥515
Elongation %
≥35 ≥35 ≥35 ≥35
Flattening Test H=1.09t/(0.09+t/D) H=1.09t/(0.09+t/D)
Flange Test 21-68%  
Intergranular corrosion
"*""Δ" ASTM E112
"Δ" min 7#, "*" min 6#
"*"﹑"Δ"ASTM E112, min 6#
Hydraulic test(Mpa) D P max P=220.6t/D D P max ASTM A530/A530M
D≤270MM P=2Rt/D
R=50%σ0.2
<25.4 7 ≤88.9 17
25.4-<38.1 10
38.1-<50.8 14 >88.9 19
50.8-<76.2 17
76.2-<127 24
≥127 31
Metallograph Analysis STM A262 E ASTM A262 E
Non-Destructive Test ASTM E213 E309 E426 ASTM E213 E309 E426
Hardness HRB<90 RB<90

Chemical composition

Grade Chemical Composition
C (max) Si (max) Mn (max) P (max) S (max) Ni Cr Mo Other
TP 304 0.08 0.75 2 0.04 0.03 8-11 18-20
TP 304H 0.04-0.10 0.75 2 0.04 0.03 8-11 18-20
TP 304L 0.035 0.75 2 0.04 0.03 8-13 18-20

TP 309S

0.08 0.75 2 0.04 0.03 8-13 18-20
TP 310S 0.08 0.75 2 0.045 0.03 12-15 22-24
TP 316 0.08 0.75 2 0.04 0.03 19-22 24-26
TP 316L 0.035 0.75 2 0.04 0.03 10-15 16-18
TP 316Ti 0.08 0.75 2 0.04 0.03 11-14 16-18
TP 317 0.08 0.75 2 0.04 0.03 11-14 16-18
TP 321 0.08 0.75 2 0.04 0.03 9-13 18-20
TP 321H 0.04-0.10 0.75 2 0.04 0.03 9-13 17-20
TP 347 0.08 0.75 2 0.04 0.03 9-13 17-20
TP 347H 0.04-0.10 0.75 2 0.04 0.03 9-13 17-20

Tolerance grade

Grade Outside diameter tolerance Grade Wall thickness tolerance
D1 ±1.50% but at least ±0.75mm T1 ±15% but at least ±0.60mm
D2 ±1.00% but at least ±0.50mm T2 ±12.5% but at least ±0.40mm
D3 ±0.75% but at least ±0.30mm T3 ±7.5% but at least ±0.15mm
D4 ±0.50% but at least ±0.10mm T4 ±5.0% but at least ±0.10mm

Tolerance standard

Item ASTM A213 ASTM A312 ASTM A269
O.D. tolerance O.D. tolerance O.D. tolerance
Outside diameter tolerance(mm) <25.4 ±0.10 10.3-48.3 +0.4/-0.8 12.7 < +0.13/-0.13
25.4-≤38.1 ±0.15 >48.3-114.3 +0.8/-0.8 12.7-38.1 +0.13/-0.13
>38.1-<50.8 ±0.20 >114.3-219.1 +1.6/-0.8 38.1-88.9 +0.25/-0.25
50.8-<63.5 ±0.25 >219.1-457.2 +2.4/-0.8 88.9-139.7 +0.38/-0.38
63.5-<76.2 ±0.30 >457.2-660.4 +3.2/-0.8 139.7-203.2 +0.76/-0.76
76.2-≤101.6 ±0.38 >660.4-864 +4/-0.8    
>101.6-≤190.5 ±0.38/-0.64 >864-1219.2 +4.8/-0.8    
>190.5-≤228.6 ±0.38/-1.14        
Thickness 
tolerance(mm)
O.D. tolerance ±12.5%t O.D. tolerance
≤38.1 +20%t/0 ≤38.1 ±15%t
>38.1 +22%t/0 >38.1 ±10%t

The Test Requirements of Standards

Standard Chemical Composition Tensile Strength Yeild Point Tension Test Rockwell Hardness Flattening Test Flaring Test Hydrostatic
ASTM A312 X X X X X
ASTM A213 X X X X X X X X
ASTM A269 X X
ASTM A511 X X X X
ASTM A789 X X X X

Standard Ultrasonic Eddy Current Intergranular Corrosion Grain size α/γ Surface Quality Tolerance
ASTM A312 X X X
ASTM A213 X X X
ASTM A269 X X X
ASTM A511 X X
ASTM A789 X X X X

ASTM Mechanical Properties

Grade Tensile Strength
Min(Mpa)
Yeild Point
Min(Mpa)
EL. Min(%) Rockwell
Max
TP 304 515 205 35 90
TP 304H 550 240 35 90
TP 304L 485 170 35 90
TP 309S 515 205 35 90
TP 310S 515 205 35 90
TP 316 515 205 35 90
TP 316L 485 170 35 90
TP 316Ti 515 205 35 90
TP 317 515 205 35 90
TP 321 515 205 35 90
TP 321H 515 205 35 90
TP 347 515 205 35 90
TP 347H 515 205 35 90

Heat treatment technology of stainless steel pipe surface

For the heat treatment technology of the surface of stainless steel pipes, non-oxidation continuous heat treatment furnaces with protective gas are generally used abroad for intermediate heat treatment and final heat treatment of finished products. As a bright surface without oxidation can be obtained, the traditional pickling process is eliminated. The adoption of this heat treatment process not only improves the surface of stainless steel pipes, but also overcomes the environmental pollution caused by pickling.

According to the manufacturer of stainless steel pipes, according to the current world development trend, bright annealing continuous heat treatment furnaces are basically divided into the following two types:

(1) Roller-type bright annealing heat treatment furnace.

This bright annealing furnace type is suitable for heat treatment of large-size and large-volume special-shaped stainless steel pipes, with an hourly output of above 1.0 Tons. The protective gases that can be used are high-purity hydrogen, decomposed ammonia and other protective gases. It can be equipped with a convection cooling system to cool the special-shaped stainless steel tube faster.

(2) Mesh belt type bright annealing heat treatment furnace.

This bright annealing furnace type is suitable for small-diameter thin-walled precision special-shaped stainless steel pipes. The hourly output is about 0.3 to 1.0 Tons. The length of the steel pipe can be up to 40m. It can also be used to process capillary tubes in coils. Equipped with convection cooling system for fast cooling. Using gas fuel or electric heating, various protective gases can be used. The stainless steel pipe after this furnace-type heat treatment has no scratches and good brightness surface.

Tensile test and hardness test of stainless steel pipe?

Tensile strength test is to make a sample of stainless steel pipe, pull the sample to break on a tensile testing machine, and then measure one or several mechanical properties, usually only the tensile strength, yield strength, elongation after fracture and section are measured Shrinkage. Tensile strength test is the most basic test method for mechanical properties of metal materials. Almost all metal materials require tensile test as long as they have requirements for mechanical properties. Especially for those materials whose shape is not convenient for hardness test, tensile strength test becomes the only means of testing mechanical properties.

The hardness test is to slowly press a hard indenter into the surface of the sample with a durometer under specified conditions, and then test the depth or size of the indentation to determine the hardness of the material. Hardness test is the simplest, fastest and easiest method in material mechanical property test. The hardness test is non-destructive, and there is an approximate conversion relationship between the material hardness value and the tensile strength value. The hardness value of the material can be converted into the tensile strength value, which has great practical significance.

Because the tensile strength test is not easy to test, and it is convenient to convert the hardness to the strength, more and more people only test the hardness of the material and less test its strength. In particular, due to the continuous advancement of hardness tester manufacturing technology and innovations, it is now possible to directly test the hardness of some materials that could not be directly tested before, such as stainless steel tube, stainless steel sheet and stainless steel strip. Therefore, there is a tendency for hardness tests to gradually replace tensile tests.