Products Description

Product Specifications

Standards	JIS G3446
Steel Grades	SUS303, SUS304, SUS304L, SUS316L, SUS316L, SUS321, SUS347, SUS821L1, SUS323L, SUS329J1, SUS329J3L, SUS329J4L, SUS405, SUS430, SUS430LX, SUS430J1L, SUS436L, SUS444, SUS445J1, SUS403, SUS410, SUS416, SUS420J1, SUS420J2, SUS431, SUS440C, SUS630, SUS631
Equivalent Standards	ASTM A269,ASTM A554,EN 10217-7,DIN 17458
Outer Diameter (OD)	6 mm – 89 mm (0.24" – 3.5")
Wall Thickness (WT)	0.3 mm – 6 mm (0.012" – 0.24")
Length	6/12,or customized
Surface Treatment	Bright Annealed
Production Process	ERW,automatic TIG welding
Condition	Solution annealed

SUS304 stainless steel welded pipe is one of the most widely used materials, exhibiting excellent corrosion resistance in common environments, such as atmospheric conditions and water. Furthermore, it possesses superior processing characteristics, allowing for cold working operations-such as bending and deep drawing-making it ideal for the fabrication of precision components with complex geometries.

The pipe is produced using TIG welding, utilizing argon gas with a purity of 99.99% or higher. This process creates a dense protective gas shield that effectively isolates the weld zone from oxygen, nitrogen, and other atmospheric gases, thereby minimizing the burn-off of alloying elements and preventing the formation of oxide films. By precisely regulating the welding current and speed, the interpass temperature is maintained at ≤150°C, effectively preventing intergranular corrosion and thermal cracking. The resulting weld seams feature excellent formation and are free from defects such as undercut or incomplete penetration.

Customized Services

Customers may select the appropriate material grade based on their specific operating conditions. Available material grades for stainless steel welded pipes include SUS303, SUS304, SUS304L, SUS316L, SUS321, SUS347, SUS821L1, SUS323L, SUS329J1, SUS329J3L, SUS329J4L, SUS405, SUS430, SUS430LX, SUS430J1L, SUS436L, SUS444, SUS445J1, SUS403, SUS410, SUS416, SUS420J1, SUS420J2, SUS431, SUS440C, SUS630, SUS631, and others.
Pipe ends can undergo chamfering and deburring, as well as specialized end-forming services such as expanding, reducing, and threading. We also provide CNC machining services, including drilling, milling, tapping, threading, grooving, and more.
We offer custom-length cutting services, with length accuracy controlled within ±0.5 mm.

Heat treament

Chemical Composition

Element	C	Si	Mn	P	S	Cr	Ni	Mo
SUS304	≤0.08	≤1.00	≤2.00	≤0.045	≤0.030	18.0 - 20.0	8.0 - 10.5	-
SUS316	≤0.08	≤1.00	≤2.00	≤0.045	≤0.030	16.0 - 18.0	10.0 - 14.0	2.0 - 3.0
SUS430	≤0.12	≤1.00	≤1.00	≤0.040	≤0.030	16.0 - 18.0	-	-

Mechanical Properties

Property	Tensile Strength (MPa)	Yield Strength 0.2% (MPa)	Elongation (%)	Hardness (HB)
SUS304	≥520	≥205	≥40	≤187
SUS316	≥520	≥205	≥40	≤187
SUS430	≥450	≥205	≥22	≤183

Possible Alternative Grades

For precision mechanical components requiring extensive welding operations, SUS304L may be utilized, as it features a lower carbon content of ≤0.03%.
For precision transmission components in the aerospace sector, as well as critical load-bearing components in high-end optical instruments, SUS630 is a suitable choice, offering high strength, excellent corrosion resistance, and good machinability.

application areas

JIS G3446 thin-walled welded stainless steel tubes are widely utilized in the field of precision machinery-where strict tolerances and smooth surface finishes are required-for applications such as shafts, sleeves, bushings, and structural components; in automotive parts, including fuel lines, sensor housings, and exhaust components; and in hydraulic and pneumatic systems.