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TP304 GRADE STAINLESS STEEL SEAMLESS PIPE

TP304L GRADE STAINLESS STEEL SEAMLESS PIPE

TP316 GRADE STAINLESS STEEL SEAMLESS PIPE

TP316L GRADE STAINLESS STEEL SEAMLESS PIPE

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TP310S GRADE STAINLESS STEEL SEAMLESS PIPE

TP321 GRADE STAINLESS STEEL SEAMLESS PIPE

904L/N08904 GRADE SS SMLS PIPE

S31803 GRADE Duplex SS SMLS PIPE

S32205 GRADE Duplex SS SMLS PIPE

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TP321 Stainless Steel Seamless Pipes from China - Reliable Suppliers & Factory for Fast Delivery

ZONSUN STEEL is a leading factory and supplier of TP321 seamless stainless steel pipes and tubes in China. Our high-quality TP321 stainless steel seamless pipes meet international standards and are ready for immediate shipment. As one of the trusted suppliers in China, we guarantee fast delivery and excellent customer service. Choose ZONSUN STEEL for reliable TP321 seamless stainless steel pipes directly from the factory

Product Detail

Introduction

TP321 is a titanium-stabilized austenitic stainless steel designed for enhanced resistance to intergranular corrosion, particularly in high-temperature environments. It is part of the 300-series stainless steels, closely related to 304/304L, but with the addition of titanium (Ti) to mitigate carbide precipitation during welding or prolonged exposure to elevated temperatures. Below is a concise overview of its characteristics and applications.

Key Features

Intergranular Corrosion Resistance Titanium stabilization ensures resistance to sensitization (chromium depletion) in welded or high-temperature (450°C–850°C) applications.

High-Temperature Stability Maintains mechanical integrity and oxidation resistance up to 870°C (1600°F), suitable for exhaust systems, heat exchangers, and boilers.

Weldability Excellent weldability without post-weld heat treatment, making it ideal for fabricated components.

General Corrosion Resistance Resists oxidation, organic acids, and mildly corrosive environments, though less resistant to chlorides than 316/316L.

Material Specification

Standard: ASTM A312/A312M

O.D: 1/8" NB TO 32" NB, (10.29MM-812.80MM), (Customization Available)

W.T: SCH 10S, SCH 40S, SCH 80S, SCH160, SCH XXS (Customization Available)

Application:

Chemical & Petrochemical Industry
Oil & Gas
Fertilizer Plant
Automotive & Aerospace
Power Generation
Food Processing
Pharmaceutical & Biotechnology
Pulp & Paper Industry
Construction & Architecture

End: Plain End, Beveled End, Threaded

Processing: Cut-to-length; Polishing.

Inspection:

100% PMI TESTED
EN10204.3.1B MILL TEST CERTIFICATE
THIRD PARTY INSPECTION ACCEPTED

Delivery Condition: Cold Drawn, Annealed and Pickled / Polished / Bright Annealed / Sand blasting / Shot Blasting.

Marking: All SS SMLS Pipes are marked as follows: Standard, Grade, OD, Thickness, Length, Heat No. (Or as per the customer’s request)

Packing: Packed in Wooden Boxes, plywood cases, Steel Strips Bundled, or as per Customers Requests

Specials: Sizes and Specifications other than above can be customized on request.

Specification Parameters

TP321 Chemical Composition

HEAT NO.		CHEMICAL COMPOSITION (%)
HEAT NO.		C	Mn	P	S	Si	Ni	Cr	N
STAND.	MIN.						9.00	17.00
STAND.	MAX.	0.08	2.00	0.045	0.030	1.00	12.00	19.00	0.10

TP321 Mechanical Properties

Mechanical Properties
Grade	Tensile Strength (MPa) min	Yield Strength 0.2% Proof (MPa) min	Elongation (% in 50mm) min	Hardness
Grade	Tensile Strength (MPa) min	Yield Strength 0.2% Proof (MPa) min	Elongation (% in 50mm) min	Rockwell B (HR B)	Brinell (HB)
TP321	515	205	35	100	220

Equivalent Grades - (ASTM A312 TP321 Equivalent Grades)

ASTM A312 TP321 Equivalent Grades
USA (ASTM/ASME/AISI)	Japan (JIS)	Germany (DIN/EN)	China (GB)	International (ISO)	United Kingdom (BS)	Russia (GOST)
TP321 UNS S32100 321 S32100	JIS G4304	X10CrNiTi18-9 (DIN) 1.4541 (EN)	06Cr18Ni11Ti (NEW) 1Cr18Ni9Ti (Old) S32168	X6CrNiTi18-10	304S12 321S20 (historical)	12Х18Н10Т

ASTM A312/A312M Standard Cold Machining Size Deviation Permitted

ASTM A312/A312M-09 Standard Permitted Tolerance of WT and OD
Nominal Outside Diameter		Allowable deviation	Nominal wall thickness		Allowable deviation
1/8”—1 1/2“	(10.29—48.26)	+0.4 -0.8	1/8”—1 1/2“	(10.29-73.03) all of t	+20 -12.5
>1 1/2“—4”	(48.26—114.3)	±0.8	3“—18”	(88.9-457.2) t/D=5%	+22.5 -12.5
>4”—8"	(114.3—219.08)	+1.6 -0.8	3“—18”	(88.9-457.2) t/D>5%	+15 -12.5
>8“—18"	(219.08—457.2)	+2.4 -0.8	≥20"	=508 t of wld pipe	+17.5 -12.5
>18”—26“	(457.2—660.4)	+3.2 -0.8	≥20"	=508 t/D=5%	+22.5 -12.5
>26”—34”	(660.4—863.6)	+4.0 -0.8	≥20"	=508 t/D>5%	+15 -12.5
>34“—48"	(863.6—1219.2)	+4.8 -0.8
Thin wall pipe (t/D=3%) ovality condition: Any cross section in a steel pipe Dmax Dmin=1.5%nominal, and (Dmax Dmin)/ 2 conforms to the stipulated diameter tolerance range.

Comparison Table Of American Standard Dimensions - (ANSI B36.19 & ANSI B36.10)

OD DN	IN	OD MM	ANSI B36.19										ANSI B36.10
			Nominal diameter in inches
			5s		10s		Sched.40s		Sched.40	Sched.80s		Sched.80	10		20		30		Standard
			mm	Kg/m	mm	Kg/m	mm	Kg/m	mm	mm	Kg/m	mm	mm	Kg/m	mm	Kg/m	mm	Kg/m	mm	Kg/m
6	1/8"	10.29	-	-	1.24	0.281	1.73	371	1.73	2.41	0.467	2.41	-	-	-	-	-	-	1.73	0.371
8	1/4"	13.72	-	-	1.65	0.499	2.24	0.644	2	3.02	0.809	3.02	-	-	-	-	-	-	2.24	0.644
10	3/8"	17.14	-	-	1.65	0.64	2.31	0.858	2.31	3.2	1.118	3.2	-	-	-	-	-	-	2.31	0.858
15	1/2"	21.34	1.65	0.814	2.11	1.016	2.77	1.26	2.77	3.73	1.62	3.73	-	-	-	-	-	-	2.77	1.26
20	3/4"	26.67	1.65	1.034	2.11	1.298	2.87	1.68	2.87	3.91	2.19	3.91	-	-	-	-	-	-	2.87	1.68
25	1"	33.4	1.65	1.312	2.77	2.125	3.38	2.5	3.38	4.55	3.23	4.55	-	-	-	-	-	-	3.36	2.5
32	1 1/4"	42.16	1.65	1.674	2.77	2.732	3.56	3.38	3.56	4.85	4.46	4.85	-	-	-	-	-	-	3.56	3.38
40	1 1/2"	48.26	1.65	1.926	2.77	3.155	3.68	4.05	3.68	5.08	5.4	5.08	-	-	-	-	-	-	3.68	4.05
50	2"	60.32	1.65	2.424	2.77	3.992	3.91	5.43	3.91	5.54	7.47	5.54	-	-	-	-	-	-	3.91	5.43
65	2 1/2"	73.02	2.11	3.747	3.05	5.345	5.16	8.62	5.16	7.01	11.4	7.01	-	-	-	-	-	-	5.16	8.62
80	3"	88.9	2.11	4.585	3.05	6.557	5.49	11.28	5.49	7.62	15.25	7.62	-	-	-	-	-	-	5.49	11.28
90	3 1/2"	101.6	2.11	5.272	3.05	7.526	5.74	13.56	5.74	8.08	18.62	8.08	-	-	-	-	-	-	5.74	13.56
100	4"	114.3	2.11	5.945	3.05	8.496	6.02	16.06	6.02	8.56	22.29	8.56	-	-	-	-	-	-	6.02	16.06
125	5"	141.3	2.77	9.639	3.4	11.74	6.55	21.76	6.55	9.52	30.92	9.52	-	-	-	-	-	-	6.55	21.76
150	6"	168.28	2.77	11.514	3.4	14.037	7.11	28.23	7.11	10.97	42.52	10.97	-	-	-	-	-	-	7.11	28.23
200	8"	219.08	2.77	15.049	3.76	20.334	8.18	42.49	8.18	12.7	64.57	12.7	-	-	6.35	33.28	7.04	36.8	8.18	42.4
250	10"	273.05	3.4	23.028	4.19	28.29	9.27	60.24	9.27	12.7	81.46	15.09	-	-	6.35	41.7	7.8	51	9.27	60.24
300	12"	323.85	3.96	31.806	4.57	36.633	9.52	73.76	10.31	12.7	97.36	17.48	-	-	6.35	49.68	8.38	65.14	9.52	73.76
350	14"	355.6	3.98	34.99	4.78	42.102	9.52	-	11.13	-	-	19.05	6.35	54.63	7.92	67.98	9.52	81.21	9.52	81.21
400	16"	406.4	4.19	42.35	4.78	48.22	9.52	-	12.7	-	-	21.44	6.35	62.58	7.92	77.9	9.52	93.13	9.52	93.18
450	18"	457.2	4.19	47.7	4.78	54.3	9.52	-	14.27	-	-	23.82	6.35	70.5	7.92	87.8	11.13	122.12	9.52	105.05
500	20"	508	4.77	60.32	5.54	69.766	9.52	-	15.09	-	-	26.19	6.35	78.47	9.52	116.97	12.7	155	9.52	116.97
550	22"	558.8	4.77	-	5.54	-	9.52	-	-	-	-	28.58	6.35	86.42	9.52	128.89	12.7	170.86	9.52	128.89
600	24"	609.6	5.54	84.1	6.35	96.215	9.52	-	17.48	-	-	30.96	6.35	96.215	9.52	140.8	14.7	209.54	9.52	140.81
650	26"	660.4	-	-	-	-	9.52	-	-	-	-	-	7.92	127.58	12.7	202.65	-	-	9.52	152.73
700	28"	711.2	-	-	-	-	9.52	-	-	-	-	-	7.92	137.52	12.7	218.54	15.88	271.94	9.52	164.65
750	30"	762	6.35	120.59	7.92	147.45	9.52	-	-	-	-	-	7.92	147.45	12.7	234.44	15.88	291.81	9.52	176.57
800	32"	812	-	-	-	-	9.52	-	17.48	-	-	-	7.92	157.39	12.7	250.33	15.88	311.67	9.52	188.5
850	34"	863.6	-	-	-	-	9.52	-	17.48	-	-	-	7.92	167.32	12.7	266.22	15.88	331.54	9.52	200.42
900	36"	914.4	-	-	-	-	9.52	-	19.05	-	-	-	7.92	177.26	12.7	282.18	15.88	351.41	9.52	212.34

Frequently Asked Questions

What is TP321 stainless steel?

TP321 is a titanium-stabilized austenitic stainless steel. It is similar to 304 stainless steel but features a titanium addition, which improves its resistance to intergranular corrosion under high-temperature environments.

Why is titanium added to TP321 stainless steel?

Titanium is added to stabilize the carbon content by forming titanium carbides. This prevents chromium carbide precipitation at grain boundaries during welding or exposure to high temperatures (450°C–850°C), protecting the steel from sensitization and subsequent intergranular corrosion.

What are the primary applications of ASTM A312 TP321?

Due to its high-temperature stability, TP321 is widely used in exhaust systems, boilers, heat exchangers, chemical processing equipment, oil & gas refineries, power generation, and aerospace components.

Does TP321 require post-weld heat treatment?

No, TP321 generally does not require post-weld heat treatment. Its titanium stabilization prevents carbide precipitation during the welding process, maintaining its corrosion resistance directly after welding.

What is the maximum operating temperature for TP321?

TP321 stainless steel maintains its mechanical strength and oxidation resistance at elevated temperatures up to approximately 870°C (1600°F).

Is TP321 resistant to chloride environments?

While TP321 has good general corrosion resistance, it is susceptible to chloride pitting and crevice corrosion. For highly corrosive chloride environments, molybdenum-bearing grades like 316 or 316L are typically preferred.