Stainless Steel Welded Pipe

Our staff are qualified and certified according to all current welding procedures, thus guaranteeing our customers longitudinally welded stainless steel pipes in line with the requirements.

Large size SS 304 stainless pipe

Large size SS 304 stainless pipe

stainless steel welded pipe for food hygiene

stainless steel welded pipe for food hygiene

A wide range of effective production facilities offers you a large number of possibilities:

Duplex Welded Stainless Steel Pipe is in the application of Petrochemical and Chemical industry, Onshore and Offshore Oil & Gas field of exploration, production and processing, Pulp and Paper-making industry, Ship Buliding industry, Coal industry and etc.

Large size SS 304 stainless pipe

Large size SS 304 stainless pipe

Large size SS 304 stainless pipe

Large size SS 304 stainless pipe

The general features of our DSSP: superior corrision resistance, such as pitting corrosion, crevice corrosion, abrasion corrosion; better weldability and mechanical properties; excellent intergranular corrosion resistance and better cost- effectiveness.

Stainless steel can withstand corrosive or chemical environments due to its smooth surface.

NPS: 1/8" through 24"

Schedules: 5, 10, 10S, 20, 30, 40, 40S, 80, 80S

Specifications: ASTM A312, ASME SA312

Inspection & Quality Control:

With a complete set of advanced testing equipment, we have the following Regular Testing Items:

Hardness test
  • Chemical Composition Analyzing;
  • Metallographic Test ;
  • Mechanical Properties Test;
  • Hydraulic Test;
  • Non-destructive Test, including X-Ray Flaw Detection;
  • Dimensional Checking;
  • Flattening
  • Flare & Flange
  • Reverse Bend
  • Reverse Flattening
  • Tensile Strength
  • Hardness
Enquiry/Ordering Information :
  • Material Grade
  • NB Pipe Size or Outside Diameter
  • Wall Thickness, Length - Random/Standard/Specific
  • Finish Required
  • Relevant Specification
  • Application/End use
Finishes :
  • As welded
  • Welded & externally polished
  • Welded Annealed & Pickled
  • Welded Cold Drawn Annealed & Pickled
  • Welded Cold Drawn Annealed Pickled & externally polished
  • Other Finishes as per customers requirement

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

Custom Grades of Stainless Steel Tube

Common Applications for Stainless Steel Tubing Stainless steel tubing has a number of uses in a wide variety of industries. It can be used during manufacturing in processing plants or can become part of a final product. Stainless steel tubing can also be used in pipelines to transport oil, gas, water, or chemicals.


Stainless steel pipe (tube) has excellent characteristics of corrosion resistance and smooth finishing. Stainless steel pipe (tube) is commonly used in demanding equipment like automobiles, food processing, water treatment facilities, oil and gas processing, refinery and petrochemicals, breweries and energy industries.

  • Machinery Parts
  • Pharmaceutical
  • Biotechnology
  • Automotive
  • Oil and Gas
  • Marine
  • Food and Beverage Processing
  • Construction
  • Automotive industries
  • Food processing
  • Water treatment facilities
  • Breweries and energy industries

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..


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

Product Specification and Size

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

Available Specification
Product Name Executive Dimension Steel Code / Steel Grade
Industrial Pipes ASTM A312, A358, A778 JIS G3459 OD: 1/4"-40"
TP304, TP304L, TP316L SUS304TP
Tubes for Boiler and Heat-Exchanger, General Service Tubing ASTM A249, A269 JIS G3463 OD: 15.9-139.8mm
WT: 1.6-5.0mm
TP304, TP304L, TP316L SUS304TB
Mechanical and Structural Tubes ASTM A554 JIS G3446 OD: 7.9-152.4mm
WT: 0.5-6.5mm
MT304, MT304L, MT316L, MT430 Grade 201, 202 as per mill's STD SUS304
Square Tubes ASTM A554 OD: 12.7x12.7-150x150mm
WT: 0.7-6.5mm
MT304, MT304L, MT316L,MT430 Grade 201, 202 as per mill's STD
Rectangular Tubes ASTM A554 OD: 10x20-100x200mm
WT: 0.7-6.5mm
MT304, MT304L, MT316L,MT430 Grade 201, 202 as per mill's STD
Sanitary Tubing ASTM A270
JIS G3447
OD: 25.4-165.2mm
WT: 0.8-3.05mm
TP304, TP304L, TP316L SUS304TBS
Large Gauge Pipes for Ordinary Piping JIS G3448 OD: 15.88-318.5mm
WT: 0.8-3.0mm
Large Diameter Pipes JIS G3468 OD: 14"-40"
Chemical Composition & Mechanical Property

Chemical Composition (For Reference)

Steel Grade C% Max. Si% Max. Mn% Max. P% Max. S% Max. Cr% Max. Ni% Max. Mo% Max. Ti% Max. Other
SUS 201 0.15 1.0 5.5-7.5 0.06 0.03 16.0-18.0 3.5-5.5 - - N:0.25
SUS 202 0.15 1.0 7.5-10.0 0.06 0.03 17.0-19.0 4.0-6.0 - - N:0.25
SUS 304 0.08 1.0 2.0 0.045 0.03 18.0-20.0 8.0-10.5 - - -
SUS 304L 0.03 1.0 2.0 0.045 0.03 18.0-20.0 9.0-13.0 - - Cu:1.0-3.0
SUS 316L 0.03 1.0 2.0 0.045 0.03 16.0-18.0 12.0-15.0 2.0-3.0 - -
SUS 430 0.12 0.75 1.0 0.04 0.03 16.0-18.0 - - - -

Mechanical Property (For Reference)

Steel Grade N/mm 2 MIN.
Tensile Stress
N/mm 2 MIN.
Proof Stress
Elongation MIN. HRB MAX. Hardness Bendability:Bending Angle Bendability:Inside Radius
SUS 201 520 275 40 100 No Require -
SUS 202 520 275 40 95 No Require -
SUS 304 520 205 40 90 No Require -
SUS 304L 480 175 40 90 No Require -
SUS 316L 480 175 40 90 No Require -
SUS 430 450 205 22 88 180° 1.0 time the thickness

the main requirement for stainless steels is that they should be corrosion resistant for a specified application or environment. The selection of a particular "type" and "grade" of stainless steel must initially meet the corrosion resistance requirements.

Welded Tube Standard Specifications
Specifications Tube Pipe Type Material Applications
ASTM A249 Welded Austenitic Steel Boiler, Superheater, Heat Exchanger, And Condenser
ASTM A268 Seamless And Welded Ferritic And Martensitic Stainless Steel General Service
ASTM A269 Seamless And Welded Austenitic Stainless Steel General Service
ASTM A270 Seamless And Welded Austenitic And Ferritic / Austenitic Stainless Steel Sanitary Tubing
ASTM A312 Seamless, Welded, And Heavily Cold Worked Austenitic Stainless Steel High-Temperature And General Corrosive Service
ASTM A358 Welded Austenitic Chromium-Nickel Stainless Steel High-Temperature Service And General Applications
ASTM A554 Welded Stainless Steel Mechanical Tubing
ASTM A688 Seamless And Welded Austenitic Stainless Steel Feedwater Heater
ASTM A789 Seamless And Welded Ferritic/Austenitic Stainless Steel General Service
ASTM A790 Seamless And Welded Ferritic/Austenitic Stainless Steel General Service
EN 10217-7 Welded Stainless Steel Pressure And Corrosion Purpose
EN 10312 Welded Stainless Steel Water And Other Liquids

Additional mechanical or physical properties may also need to be considered to achieve the overall service performance requirements.

Welding Methods

Welded stainless steel tube is made from long strip or sheet, passed a rolling machine, then the strip edges is welded longitudinally and melt together, using various welding processes, making welding beam is as same as base metal, and form into tube shape.

The sheet width is desired tube outside diameter, the width should be calculated before manufacturing.


Tungsten Inert Gas welding, another name for Gas tungsten arc welding (GTAW), is an arc welding process that uses a non-consumable tungsten electrode to produce the weld. The weld area and electrode is protected from oxidation or other atmospheric contamination by an inert shielding gas.


Electric Fusion Welding, Electric Fusion Welding (EFW steel pipe) refers to an electron beam welding, the use of high-speed movement of the electron beam directed impact kinetic energy is converted to heat the workpiece so that the workpiece leaving the melt, the formation of the weld. It is mainly used for welding dissimilar steel welding sheet or which high power density, metal weldment can rapidly heated to high temperatures, which can melt any refractory metals and alloys.


Electric Resistance Welding, high-frequency electrical current is passed between the material edges, then the edges are forced together under pressure as a butt joint and then welded by heating the material to high temperatures.


Double Submerged arc welded, similar to other pipe manufacturing processes, the manufacture of Double Submerged Arc Welded Pipe involves first forming steel plates into cylindrical shapes. The edges of the rolled plate are formed so that V-shaped grooves are formed on the interior and exterior surfaces at the location of the seam. The pipe seam is then welded by a single pass of an arc welder on the interior and exterior surfaces.


Longitudinal Submerge-arc Welded, LSAW (Longitudinally Submerged Arc Welded Steel pipes) in leaflets plate as raw material, the steel plate in the mold or molding machine pressure (volume) into using double-sided submerged arc welding and flaring from production.


High Frequency Welding, HFW welded steel pipes are widely preferred in Oil, Natural Gas, Water and other liquids transportation and distribution lines, heating, cooling, ventilation piping and steel structures for construction and other general purposes by means of precise production tolerances and high capacity manufacturing method.

Heat treatment is generally required after manufacture, this process improves stainless steel welded tube properties, help welded tube suitable for wide applications.

Welded Tubes Quality Control

All stages from raw material to finished products, tube manufactured under strict quality control, making sure tube having stable mechanical properties, excellent surface finish and high dimensional accuracy.

Standard Testing

  • Tensile Strength test
  • Flattening test
  • Flare test
  • Flange test
  • Dimensional inspection
  • PMI
  • Hardness test
  • Eddy Current test

Optional Testing

  • Ultrasonic test
  • Hydrostatic test
  • Air Under Water test
  • Grain Size
  • Corrosion test
  • Metallographic
  • Radiographic test.

Welded Tube VS Seamless Tube

There are differences between welded tube and seamless in manufacturing, typical appearance is that welded have welding seam, without or with additional filler metal, but seamless tube have not.

Size Range

Welded tube can be produced in a wide range sizes and dimensions, both large diameter and small diameter, it is hard to produce very large size and very thin wall seamless tube.

Production Time

Welded tube have short production time, because it posses more simple manufacturing process, in most condition, for seamless tube, several producing processes are needed to duplicate, such as cold rolling, heat treatment.

Working Pressures

Working pressures of the welded tube are approximately 20% less than the seamless tube, seamless tube is better selection use in harsh environment.

Production Cost

Obviously, welded tube is effective cost choice for many applications, seamless tube have higher price, but it is also durable.


Welded tubes have excellent concentricity, tight tolerance in outside diameter and wall thickness.

Delivery requirment:

Capped end stainless steel tube

  • Package: knitting strip bundle, wooden box or steel box
  • Mill test certificate: according to EN 10204 3.2
  • Inspection: Third party inspection, or by clints
Capped end stainless steel tube
Tubes putted in wooden boxes

Tubes putted in wooden boxes

  • Marking: SunnySteel, material grade, standard, specification, heat no.

The wooden boxes packing for stainless products

  • Surface Treatment: Bright annealed, polished outside and inside surface.
Stainless Steel Seamless Pipes
Stainless Steel Seamless Pipes


Pipe size range:

  • Outside diameter: range from 6mm to 530mm.
  • Wall thickness: SCH5S, SCH10S, SCH40S, SCH80S, SCH 120S
  • Legnth: unbending length or fix length