Name: Stainless Steel Welded Pipe
Brand: Sunny Steel
Availability: InStock
Rating: 4.8 (128 reviews)

Stainless steel welded pipes are indispensable in modern engineering and industry. Their unmatched combination of strength, durability, and resistance to corrosion ensures they remain a preferred choice for diverse applications. Whether you’re constructing skyscrapers or building pipelines, stainless steel welded pipes provide a reliable, long-lasting solution.

Stainless steel is a low-cost and corrosion-resistant material with a high level of durability. It is ideal for both residential and marine applications. Not only is it durable and long-lasting with a perfect surface finish, but it also has excellent strength.

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

Corrosion resistant pipes with outer diameters from 15 to 2 032 mm (80 inch) and wall thicknesses up to 70 mm
Pipes are made from special alloys, titanium or clad materials
Pipes with demanding tolerance requirements
Pipes in special geometric shapes
Pipes according to internationally valid standards, including DIN, DIN EN, DIN EN ISO, NORSOK, API and ASTM

Features of Stainless Steel Welded Pipes

Corrosion Resistance: Made from high-grade stainless steel, these pipes resist rust and corrosion, even in harsh environments.
Durability: Their robust construction ensures long service life with minimal maintenance.
Aesthetic Appeal: With a polished finish, they offer a sleek and modern appearance.
Customizability: Stainless steel welded pipes can be customized for specific sizes, shapes, and grades.
Eco-Friendly: Stainless steel is 100% recyclable, contributing to sustainable construction practices.

Benefits of Stainless Steel Welded Pipes

Cost-Effectiveness: Compared to seamless pipes, welded pipes are more affordable while offering similar performance.
Versatility: Suitable for a wide range of industrial and residential applications.
Consistency: Uniform wall thickness and shape make them reliable for precise engineering tasks.
Availability: Readily available in various sizes and grades to meet immediate project needs.

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.

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

Enquiry/Ordering Information

Material Grade
NB Pipe Size or Outside Diameter
Wall Thickness, Length - Random/Standard/Specific

Finish Required
Relevant Specification
Application/End use

Manufacturing process of Welded Stainless Steel Pipe

Material Selection: High-quality stainless steel is chosen based on the application’s requirements.
Forming: Steel strips are rolled into a circular shape.
Welding: Edges are welded using advanced techniques like TIG (Tungsten Inert Gas) welding.
Post-Welding Treatment: Pipes undergo heat treatment to enhance mechanical properties.
Surface Finishing: Polishing removes impurities, ensuring a smooth surface.
Quality Inspection: Pipes are tested for strength, durability, and resistance to corrosion.

Comparison Table of Stainless Steel Grades by Country

To simplify grade identification and align with international designations, China adopted the “Universal Code System for Steel and Alloy Grades” (e.g. 06Cr19Ni10 corresponds to 304). While chemical compositions vary slightly between standards, each grade is governed by its national standard.

Reference standards:

China: GB/T 20878, GB/T 1220
Japan: JIS G 4303 / G 4304
USA: ASTM A240 / A276 + UNS
Korea: KS D 3705 (STS series)
Europe: EN 10088-1 (Werkstoff No.)
India: IS 6603
Australia: AS 2837 (or proprietary approx.)
Taiwan: CNS 8470

No	China (GB)		Japan (JIS)	USA		Korea (KS)	Europe (EN Werkstoff)	India (IS)	Australia	Taiwan (CNS)
No	Old	New (2007)	SUS	ASTM	UNS	STS	W.-Nr.	IS	Approx.	CNS
Austenitic stainless steel
1	1Cr17Mn6Ni5N	12Cr17Mn6Ni5N	SUS201	201	S20100	STS201	1.4372	10Cr17Mn6Ni4N20	201-2	201
2	1Cr18Mn8Ni5N	12Cr18Mn9Ni5N	SUS202	202	S20200	STS202	1.4373	–	–	202
3	1Cr17Ni7	12Cr17Ni7	SUS301	301	S30100	STS301	1.4319	10Cr17Ni7	301	301
4	0Cr18Ni9	06Cr19Ni10	SUS304	304	S30400	STS304	1.4301	07Cr18Ni9	304	304
5	00Cr19Ni10	022Cr19Ni10	SUS304L	304L	S30403	STS304L	1.4306	02Cr18Ni11	304L	304L
6	0Cr19Ni9N	06Cr19Ni10N	SUS304N1	304N	S30451	STS304N1	1.4315	–	304N1	304N1
7	0Cr19Ni10NbN	06Cr19Ni9NbN	SUS304N2	XM21	S30452	STS304N2	–	–	304N2	304N2
8	00Cr18Ni10N	022Cr19Ni10N	SUS304LN	304LN	S30453	STS304LN	–	–	304LN	304LN
9	1Cr18Ni12	10Cr18Ni12	SUS305	305	S30500	STS305	1.4303	–	305	305
10	0Cr23Ni13	06Cr23Ni13	SUS309S	309S	S30908	STS309S	1.4833	–	309S	309S
11	0Cr25Ni20	06Cr25Ni20	SUS310S	310S	S31008	STS310S	1.4845	–	310S	310S
12	0Cr17Ni12Mo2	06Cr17Ni12Mo2	SUS316	316	S31600	STS316	1.4401	04Cr17Ni12Mo2	316	316
13	0Cr18Ni12Mo3Ti	06Cr17Ni12Mo2Ti	SUS316Ti	316Ti	S31635	–	1.4571	04Cr17Ni12MoTi20	316Ti	316Ti
14	00Cr17Ni14Mo2	022Cr17Ni12Mo2	SUS316L	316L	S31603	STS316L	1.4404	02Cr17Ni12Mo2	316L	316L
15	0Cr17Ni12Mo2N	06Cr17Ni12Mo2N	SUS316N	316N	S31651	STS316N	–	–	316N	316N
16	00Cr17Ni13Mo2N	022Cr17Ni13Mo2N	SUS316LN	316LN	S31653	STS316LN	1.4429	–	316LN	316LN
17	0Cr18Ni12Mo2Cu2	06Cr18Ni12Mo2Cu2	SUS316J1	–	–	STS316J1	–	–	316J1	316J1
18	00Cr18Ni14Mo2Cu2	022Cr18Ni14Mo2Cu2	SUS316J1L	–	–	STS316J1L	–	–	–	316J1L
19	0Cr19Ni13Mo3	06Cr19Ni13Mo3	SUS317	317	S31700	STS317	–	–	317	317
20	00Cr19Ni13Mo3	022Cr19Ni13Mo3	SUS317L	317L	S31703	STS317L	1.4438	–	317L	317L
21	0Cr18Ni10Ti	06Cr18Ni11Ti	SUS321	321	S32100	STS321	1.4541	04Cr18Ni10Ti20	321	321
22	0Cr18Ni11Nb	06Cr18Ni11Nb	SUS347	347	S34700	STS347	1.4550	04Cr18Ni10Nb40	347	347
Austenitic-ferritic (Duplex) stainless steel
23	0Cr26Ni5Mo2	–	SUS329J1	329	S32900	STS329J1	1.4477	–	329J1	329J1
24	00Cr18Ni5Mo3Si2	022Cr19Ni5Mo3Si2N	SUS329J3L	–	S31803	STS329J3L	1.4462	–	329J3L	329J3L
Ferritic stainless steel
25	0Cr13Al	06Cr13Al	SUS405	405	S40500	STS405	1.4002	04Cr13	405	405
26	–	022Cr11Ti	SUH409	409	S40900	STS409	1.4512	–	409L	409L
27	00Cr12	022Cr12	SUS410L	–	–	STS410L	–	–	410L	410L
28	1Cr17	10Cr17	SUS430	430	S43000	STS430	1.4016	05Cr17	430	430
29	1Cr17Mo	10Cr17Mo	SUS434	434	S43400	STS434	1.4113	–	434	434
30	–	022Cr18NbTi	–	–	S43940	–	1.4509	–	439	439
31	00Cr18Mo2	019Cr19Mo2NbTi	SUS444	444	S44400	STS444	1.4521	–	444	444
Martensitic stainless steel
32	1Cr12	12Cr12	SUS403	403	S40300	STS403	–	–	403	403
33	1Cr13	12Cr13	SUS410	410	S41000	STS410	1.4006	12Cr13	410	410
34	2Cr13	20Cr13	SUS420J1	420	S42000	STS420J1	1.4021	20Cr13	420	420J1
35	3Cr13	30Cr13	SUS420J2	–	–	STS420J2	1.4028	30Cr13	420J2	420J2
36	7Cr17	68Cr17	SUS440A	440A	S44002	STS440A	–	–	440A	440A

Stainless Steel Tube & Pipe Tolerances

During manufacturing, the actual dimensions of stainless steel tubes and pipes often deviate from the nominal sizes. Such deviations are defined as tolerances and have been strictly standardized.

A positive deviation is called positive tolerance, and a negative deviation is called negative tolerance.

Outside diameter (OD), wall thickness and length are the three fundamental parameters in stainless steel tube & pipe manufacturing and distribution. Among them, OD and wall thickness are critical to structural design, fluid conveyance and downstream processing.

Nominal vs Actual Size

A. Nominal Pipe Size: The idealized dimension specified in standards such as ASME B36.10M and ASME B36.19M. It is the ordered size stated in contracts.

B. Actual Pipe Size: The real dimension obtained after production. Deviation occurs when the actual size is larger or smaller than the nominal size.

European Standard

European standards define four tolerance classes for OD and wall thickness based on the nominal dimension, expressed either as percentages or absolute values. Larger diameters or heavier walls typically use percentage tolerances, while small-diameter or thin-wall tubes use absolute values.

Standard	Process & Type	OD Tolerance		Wall Thickness Tolerance	Remarks
Standard	Process & Type	OD (mm)	Class	Wall Thickness Tolerance	Remarks
EN 10216-5	Hot Finished Seamless	219.1–610	D1	+22.5%T, –15%T	T/D ≤ 0.05
				T1	T/D ≤ 0.09
				T2	T/D > 0.09
		30–219.1	D2	T1
		30–219.1	D2	T2
	Cold Finished Seamless	≤219.1	D3	T3
	Cold Finished Seamless	≤219.1	D4	T4	By agreement
EN 10297-2	Hot Finished Seamless	–	D1	T1
	Hot Finished Seamless	–	D2	T2	By agreement
	Cold Finished Seamless	–	D3	T3
	Cold Finished Seamless	–	D4	T4	By agreement
EN 10217-7	Welded	>168.3	D2	T3
		≤168.3	D3	T3
		≤168.3	D4	T3	By agreement
EN 10296-2	Welded	>168.3	D2	T3
		≤168.3	D3	T3
		≤114.3	D4	T3	By agreement
EN 10312	Welded	Series 1	D4	T3	T = 0.6–2 mm
EN 10312	Welded	Series 2	D3–D4	T3–T4	T = 1–3 mm

OD classes D1–D4 and wall thickness classes T1–T4 follow DIN EN ISO 1127: Dimensions, tolerances and conventional masses per unit length.

Outside Diameter		Wall Thickness
Class	Tolerance	Class	Tolerance
D1	±1.5% or ±0.75 mm min.	T1	±15% or ±0.6 mm min.
D2	±1.0% or ±0.5 mm min.	T2	±12.5% or ±0.4 mm min.
D3	±0.75% or ±0.3 mm min.	T3	±10% or ±0.2 mm min.
D4	±0.50% or ±0.1 mm min.	T4	±7.5% or ±0.15 mm min.
		T5	±5.0% or ±0.10 mm min.

Where both percentage and absolute values apply, the greater value shall be used.

USA Standard

ASTM specifications are primarily governed by ASTM A999/A999M and A1016/A1016M.

ASTM A999	ASTM A1016
A312 / A312M A358 / A358M A376 / A376M A409 / A409M A778 A790 / A790M A813 / A813M A814 / A814M A928 / A928M	A213 / A213M A249 / A249M A268 / A268M A269 A270 A688 / A688M A789 / A789M A803 / A803M

A511 (seamless mechanical tubing) and A554 (welded mechanical tubing) are exceptions and have independent tolerance tables.

Standard	Process / Condition	OD (mm)	OD Tolerance (mm)	Wall Thickness T (mm)	Wall Thickness Tolerance
Standard	Process / Condition	OD (mm)	OD Tolerance (mm)	Wall Thickness T (mm)	Minimum	Average
ASTM A1016/A1016M	Hot Drawn Seamless	≤100	+0.4 / –0.8	≤2.4	+0.4t / 0
		100–200	+0.4 / –1.2	2.4–3.8	+0.35t / 0
		200–225	+0.4 / –1.6	3.8–4.6	+0.33t / 0
				≥4.6	+0.28t / 0
	Cold Drawn Seamless	<25	±0.1		+0.20t / 0	±0.10t
		25–40	±0.1		+0.20t / 0	±0.10t
		40–50	±0.2		+0.22t / 0	±0.10t
		50–65	±0.25		+0.22t / 0	±0.10t
		65–75	±0.3		+0.22t / 0	±0.10t
		75–100	±0.38		+0.22t / 0	±0.10t
		100–200	+0.38 / –0.04		+0.22t / 0	±0.10t
		200–250	+0.38 / –1.14		+0.22t / 0	±0.10t
	Welded	40–50	±0.2		+0.18t / 0	±0.10t
		50–65	±0.25		+0.18t / 0	±0.10t
		65–75	±0.3		+0.18t / 0	±0.10t
		75–100	±0.38		+0.18t / 0	±0.10t
		100–200	+0.38 / –0.04		+0.18t / 0	±0.10t
		200–250	+0.38 / –1.14		+0.18t / 0	±0.10t
ASTM A999	Seamless & Welded	<48.3	+0.4 / –0.8			–0.125t
ASTM A312	Seamless & Welded	48.3–114.3	±0.8	OD=10.3–73		+0.20t / –0.125t
		168.3–219.1	+1.6 / –0.8	t/OD≤5%, OD=88.9–457.2		+0.225t / –0.125t
		219.1–457.2	+2.4 / –0.8	t/OD>5%, OD=88.9–457.2		+0.15t / –0.125t
	Welded	508–660	+3.2 / –0.8	OD≥508		+0.175t / –0.125t
	Welded	711–864	+4.0 / –0.8	t/OD≤5%, OD≥508		+0.225t / –0.125t
	Seamless	914–1209	+4.8 / –0.8	t/OD>5%, OD≥508		+0.15t / –0.125t
ASTM A409	Welded		±0.2% (t<4.8) ±0.4% (t≥4.8)
ASTM A358	Welded		±0.50%
ASTM A511	Seamless Mechanical	≤12.7	±0.1			±0.15t
		12.7–38.1	±0.2			±0.10t
		38.1–88.9	±0.3			±0.10t
		88.9–139.7	±0.4			±0.10t
		139.7–203.1	±0.8			±0.10t
		203.1–220	±1.1			±0.10t
		220–325	±1.6			±0.10t

U.S. standards predominantly use absolute OD tolerances, often asymmetrical. In many cases, average OD accuracy exceeds D4 class per EN ISO 1127.

Typical wall thickness tolerance: ±10%t or tighter. Pipeline products allow larger tolerances, with hot-finished seamless pipe being the most permissive.

China Standards

China’s stainless steel tube & pipe standards are broadly aligned with European practice, while incorporating select provisions from U.S. specifications.

Specification	Process	OD (mm)	OD Tolerance	Wall (mm)	Wall Tolerance
GB 13296	Cold Rolled Seamless	6–30	±0.15 / –0.2	1–3	+20%	0%
		>30–50	±0.3	>3	+22%	0%
		>50	±0.75%	Average wall thickness applies
GB/T 14976	Cold Rolled Seamless	6–10	±0.15	1–3	+12.5%	–12.5%
		10–30	±0.2	>3	+12.5%	–10%
		30–50	±0.3	Average wall: +22%
		>50	±0.8%	Average wall: +22%

Standard Comparison

Wall thickness tolerances in Chinese standards are generally comparable to mainstream U.S. and European specifications, though slightly less stringent than the highest EU accuracy classes.

OD tolerances in Chinese standards are typically tighter than U.S. requirements and approach EU levels. U.S. standards place stronger emphasis on tight OD control relative to wall thickness.

Neither Chinese nor European standards prescribe weight tolerances. Seamless tubes may be delivered by actual or theoretical weight; welded tubes are typically delivered by theoretical weight, optionally by actual weight.

Out of Roundness (Ovality)

Ovality is the difference between the maximum and minimum OD measured on the same cross-section. It is determined by measuring the high and low points of the tube or pipe.

Stainless steel tube ovality measurement

Eccentricity / Concentricity

Eccentricity describes variation in wall thickness around the circumference. High-precision applications require tight concentricity.

Stainless steel tube wall thickness eccentricity

EN standards incorporate concentricity within wall thickness tolerances. ASTM A1016/A1016M specifies concentricity for OD ≥ 50 mm and t ≥ 5.6 mm.

Seamless tubes:

WTmax – WTmin ≤ ±10% × (WTmax + WTmin) / 2

Welded tubes:

WTmax – WTmin ≤ 5% × (WTmax + WTmin) / 2

Straightness

Standard tubes are supplied straightened to the eye. For special applications, permissible deviation from straightness may be agreed upon. It is expressed per unit length, e.g. 1 mm per 1000 mm.

Straightness Examples

OD (mm) ≤	OD (inches) ≤	Wall	Commercial Straightness	Achievable (mm/m)
15.9	0.625	All sizes	1 in 600	1 in 2000
25.4	1.00	≥2% of OD	1 in 600	1 in 1500
25.4	1.00	<2% of OD	1 in 400	1 in 1000

Length Types

Delivery length is the length requested by the purchaser and specified in the contract. Standards define several types:

A. Normal / Random Length: Within the standard range, without fixed length requirement. Example: hot-finished pipe 3000–12000 mm; cold-drawn pipe 2000–10500 mm.

B. Fixed Length: A specific length within the normal range. An allowable positive deviation applies.

Length Regulations

Fixed-length production yields significantly lower than random length. Price premiums of approximately 10% are common.

C. Multiple Length: Total length is a multiple of a single length, with an additional cutting allowance. Example: 3000 mm × 3 = 9000 mm total.

Cutting allowances: 5–10 mm for OD ≤ 159 mm; 10–15 mm for OD > 159 mm.

D. Range Length: A defined length interval within the normal range. Example: 6000–8000 mm or 8000–10000 mm. Premiums of ~4% are typical.

Difference Between Seamless and Welded Tube & Pipe

Seamless and welded tubes and pipes are the two primary product forms for stainless steel. For decades, there has been ongoing discussion regarding which type offers superior performance.

With advances in metallurgy and welding technology, the debate now centers on structural integrity and corrosion resistance—particularly within the weld zone of welded products. Fundamentally, the key distinction lies in the manufacturing process.

Difference Between Seamless and Welded Tube & Pipe

In certain highly corrosive or high-pressure applications, selecting a higher-performance alloy—rather than simply choosing seamless over welded—may be the most effective solution.

Strip-Welded Tube & Pipe

Strip-welded tubes are produced from stainless steel coils or strips. The strip passes through grooved rollers, gradually forming a circular profile. As the edges converge, they are joined by automatic welding.

The most common welding process is TIG (GTAW), which provides excellent protection of the weld seam and consistent metallurgical quality.

After welding, the seam is typically ground flush, followed by solution annealing or stress-relief heat treatment, depending on application requirements. Modern production lines often integrate inline induction annealing, straightening, dimensional calibration, cutting to length, deburring and non-destructive testing.

Manufacturing

Coil inspection & analysis
Slitting
Roll forming
Automatic TIG welding
Seam grinding
Solution annealing
Straightening & calibration
Cutting to length

Finishing & Testing

Pickling & passivation
End facing
Eddy current testing
Hydrostatic / air-under-water test
Final inspection
Marking
Packing

TIG welding of stainless steel tubing

Heavy Wall & Large Diameter Welded Pipe

For large-diameter or heavy-wall pipes, the manufacturing route differs. Production begins with stainless steel plates rather than strips. Plates are plasma-cut to size, edge-prepared, and formed using roller bending machines or hydraulic presses.

Welding methods such as EFW (Electric Fusion Welding) or ERW (Electric Resistance Welding) are commonly applied. For critical services, double-sided welding may be employed to ensure full penetration and structural integrity.

Manufacturing

Plate inspection
Plasma cutting
Edge milling / preparation
Roll bending / pressing
Seam cleaning
Automatic welding
Degreasing
Annealing

Finishing & Inspection

Roundness calibration
End facing
Eddy current testing
Radiographic testing (RT)
Hydrostatic testing (HT)
Final inspection
Marking & packing

For large-diameter welded pipes, radiographic examination (RT) and hydrostatic testing (HT) are typically mandatory. Double-sided welding is commonly accepted and specified for high-integrity applications.

Delivery, Packing & Value-Added Services

Delivery Condition

Common delivery conditions for stainless steel tubes and pipes: cold-hard (BK), cold-soft (BKW), stress-relieved (BKS), annealed (GBK), and normalized (NBK).

Condition Symbols

Term	Symbol	Explanation
Cold-finished / Hard	BK	No heat treatment after final cold-forming. Low deformability.
Cold-finished / Soft	BKW	Light finishing pass after heat treatment. Limited cold-formability (bending, expanding).
Annealed	GBK	Annealed after final cold-forming in controlled atmosphere or vacuum.
Normalized	NBK	Annealed above upper transformation point in controlled atmosphere or vacuum.

Packing

Bare packing / bundle packing / crate packing with wooden protection at both ends, suitable for seaworthy delivery or as requested.

While hundreds of packing methods exist, two principles are mandatory: corrosion prevention and secure sea transport.

Steel strapping for fixed stainless steel pipes

Plastic end caps on both pipe ends
Steel strapping to prevent transport damage
Uniform and consistent bundle marking
Same bundle from identical heat / furnace
Same grade, specification and heat number

Sunny Steel packing can be fully customized to meet customer requirements.

Stainless steel pipe bundle packing with plastic caps

Stainless steel pipe wooden crate packing

Stainless steel pipe seaworthy bundle packing

ASTM A179 tube bundle with steel strapping

Container Loading

Steel pipe bundle securing inside container

Final securing of steel pipes in container

Seaworthy container loading of alloy pipes

Value-Added Services

Beveling

Stainless steel tubes can be beveled at one or both ends to match complementary joints. Beveling simplifies welding preparation, reduces on-site cutting time and lowers installation costs.

Heat Treating & Annealing

Sunny Steel provides heat treatment for selected 400-series stainless steels. Processes include stress relieving, tempering, quenching, normalizing and solution annealing to achieve required mechanical properties and microstructure.

Honing & Turning

Honing and turning refine the internal surface of tubes and pipes to precise diameters and geometric tolerances. This secondary operation relieves residual stress and improves surface finish after drilling, reaming and heat treatment.

Polishing

Internal and external polishing is available to meet sanitary, pharmaceutical and high-purity process requirements.

Positive Material Identification (PMI)

PMI testing verifies alloy composition to ensure compliance with specifications. Sunny Steel performs in-house PMI or coordinates with independent laboratories for critical applications.

Ultrasonic Testing (UT)

UT uses high-frequency sound waves to detect internal flaws, measure wall thickness and verify material integrity. This non-destructive test is routinely applied to seamless and welded stainless steel tubes.

All products are supplied with EN 10204 3.1 Mill Test Certificates. Third-party inspection (SGS, BV, TÜV) is available upon request.

Product Name	Executive Standard	Dimension	Steel Code / Steel Grade
Industrial Pipes	ASTM A312, A358, A778 JIS G3459	OD: 1/4"-40" WT: SCH5S-SCH80S	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	SUS304TPD
Large Diameter Pipes	JIS G3468	OD: 14"-40" WT: SCH5S-SCH40S	SUS304TPY

Steel Grade	Ni% Max.	Cr% Max.	C% Max.	Si% Max.	Mn% Max.	P% Max.	S% Max.	Mo% Max.	Ti% Max.	Other
SUS201	3.5-5.5	16.0-18.0	0.15	1.0	5.5-7.5	0.06	0.03	-	-	N: 0.25
SUS202	4.0-6.0	17.0-19.0	0.15	1.0	7.5-10.0	0.06	0.03	-	-	N: 0.25
SUS304	8.0-10.5	18.0-20.0	0.08	1.0	2.0	0.045	0.03	-	-	-
SUS304L	9.0-13.0	18.0-20.0	0.03	1.0	2.0	0.045	0.03	-	-	-
SUS316L	12.0-15.0	16.0-18.0	0.03	1.0	2.0	0.045	0.03	2.0-3.0	-	-
SUS430	0.60	16.0-18.0	0.12	0.75

Steel Grade	N/mm 2 MIN. Tensile Stress	N/mm 2 MIN. Proof Stress	% MIN. Elongation	HRB MAX. Hardness	Bendability: Bending Angle	Bendability: Inside Radius
SUS201	520	275	40	100	No Require	-
SUS202	520	275	40	95	No Require	-
SUS304	520	205	40	90	No Require	-
SUS304L	480	175	40	90	No Require	-
SUS316L	480	175	40	90	No Require	-
SUS430	420	205	22	88	180°	1.0 time the thickness

Grade Family	Typical Grades	Density (g/cm³)	Density (kg/m³)
Austenitic (Cr-Ni)	201, 202, 301, 302, 303, 304, 304L, 304LN, 305, 321	7.93	7930
Austenitic (Mo-bearing)	309S, 310S, 316, 316L, 316Ti, 316LN, 317, 317L, 347	7.98	7980
Super Austenitic	904L	7.98	7980
Duplex	2205 / S31803	7.80	7800
Super Duplex	S32750	7.85	7850
Martensitic	403, 410, 410S, 416, 431	7.75	7750
Martensitic (High C)	440A / 440C	7.74 / 7.62	7740 / 7620
Martensitic	420	7.73	7730
Ferritic	439, 430, 430F	7.70	7700
Ferritic (Mo-bearing)	434 / 444	7.74 / 7.75	7740 / 7750
Ferritic	405	7.72	7720

Alloying Elements	Effect on the Properties
Chromium	Increases Resistance to corrosion and oxidation. Increases hardenability and wear resistance. Increases high temperature strength.
Nickel	Increases hardenability. Improves toughness. Increases impact strength at low temperatures.
Molybdenum	Increases hardenability, high temperature hardness, and wear resistance. Enhances the effects of other alloying elements. Eliminate temper brittleness in steels. Increases high temperature strength.
Manganese	Increases hardenability. Combines with sulfur to reduce its adverse effects.
Vanadium	Increases hardenability, high temperature hardness, and wear resistance. Improves fatigue resistance.
Titanium	Strongest carbide former. Added to stainless steel to prevent precipitation of chromium carbide.
Silicon	Removes oxygen in steel making. Improves toughness. Increases hardness ability
Boron	Increases hardenability. Produces fine grain size.
Aluminum	Forms nitride in nitriding steels. Produces fine grain size in casting. Removes oxygen in steel melting.
Cobalt	Increases heat and wear resistance.
Tungsten	Increases hardness at elevated temperatures. Refines grain size.

Stainless Steel Welded Pipe

What Are Stainless Steel Welded Pipes?

Features of Stainless Steel Welded Pipes

Benefits of Stainless Steel Welded Pipes

Enquiry/Ordering Information

Manufacturing process of Welded Stainless Steel Pipe

Inspection & Quality Control

Finishes