1. The pipe making process is different. Seamless stainless steel pipe, also known as stainless steel seamless pipe, is made of steel ingots or solid tube blanks through perforation to make capillaries, and then hot-rolled, cold-rolled or cold-drawn. Stainless steel welded pipe is made of stainless steel plate. 2. Welds. The decorative 304 stainless steel welded pipe has welded seams due to the pipe making process, but the seamless steel pipe has no welds like its name. Good quality decorative stainless steel welded pipe, all welds are protected by nitrogen. 3. Thickness. The raw material steel strips of stainless steel welded pipes are all processed by calendering, and the thickness is relatively uniform. However, the thickness of stainless steel seamless pipes is often uneven, and they are relatively thick pipes. 4. Welding performance. Under normal circumstances, there are certain differences in the chemical composition of 304 seamed stainless steel pipes and seamless stainless steel pipes. The steel composition for the production of seamless stainless steel pipes is only the basic requirements of astm. For the production of welded stainless steel pipes, the steel contains chemical components suitable for welding, such as silicon, sulfur, manganese, oxygen, and the mixing of elements such as ferrite in a certain proportion, which can produce a kind of easy heat transfer during the welding process. the weld melt, so that the entire weld is penetrated. For seamless stainless steel pipes, due to the lack of the above elements, various unstable factors will occur during the welding process, which is not easy to weld firmly and cannot be welded through. 5. Corrosion resistance. Under normal circumstances, the corrosion resistance of two stainless steel pipes and seamless pipes of the same material is basically the same. 6. Price. The price of seamless steel pipe is higher than that of welded stainless steel pipe. 7. Overall quality. Generally speaking, the quality of 304 seamed stainless steel pipe is better than that of seamless stainless steel pipe. This is because the welded stainless steel pipe is made of an accurate cold-rolled sheet that has passed the inspection, so the defects are basically at the weld. The 304 seamless stainless steel pipe is punched from a stainless steel billet by a punch, resulting in many tears in the extruded pipe wall. Eddy current testing has shown that the defect rate of slotted stainless steel pipe will generally be lower than that of seamless stainless steel pipe. 8. Surface. The surface requirements of seamless pipes are not strict, and there will be less obvious spots. The surface treatment requirements of stainless steel decorative pipes are stricter. 9. Purpose. Seamless pipes are mainly industrial pipes. Decorative pipes are widely used, mainly in the field of decorative welding, but as decorative stainless steel pipes become better and better, there are also thick-walled decorative pipes that will replace some seamless steel pipes.Stainless steel pipe welding processes include: argon arc welding, gas welding, submerged arc welding, manual welding, MIG/MAG welding, and TIG welding. Welding process used: The use of small specifications can prevent the occurrence of intergranular corrosion, thermal cracks and deformation, and the welding current is 20% lower than that of low carbon steel; In order to ensure the stable combustion of the arc, DC reverse connection is adopted; In short arc welding, the arc should be closed slowly, the arc crater should be filled, and the surface in contact with the medium should be welded last; The temperature between layers should be controlled during multi-layer welding, and forced cooling can be adopted after welding; Do not start the arc outside the groove, and the ground wire should be connected well; the deformation after welding can only be corrected by cold working.

Product Name	Stainless Steel Welded Pipe
Steel grade	300 series
Standard	ASTM A213, A312, ASTM A269, ASTM A778, ASTM A789, DIN 17456, DIN17457, DIN 17459, JIS G3459, JIS G3463, GOST9941, EN10216, BS3605, GB13296
Material	304, 304L, 309S, 310S, 316, 316Ti, 317, 317L, 321, 347, 347H, 304N, 3 16L, 316N, 201, 202
Surface	Polishing, annealing, pickling, bright
Type	hot rolled and cold rolled
stainless steel round pipe/tube
Size	Wall thickness	1mm-150mm(SCH10-XXS)
	Outer diameter	6mm-2500mm (3/8"-100")
stainless steel square pipe/tube
Size	Wall thickness	1mm-150mm(SCH10-XXS)
	Outer diameter	4mm*4mm-800mm*800mm
stainless steel rectangular pipe/tube
Size	Wall thickness	1mm-150mm(SCH10-XXS)
	Outer diameter	6mm-2500mm (3/8"-100")
	Length	4000mm, 5800mm, 6000mm, 12000mm, or as required.
Trade terms	Price terms	FOB, CIF, CFR, CNF, Ex-work
	Payment terms	T/T, L/C, westen union
Delivery time	Prompt delivery or as the order quantity.
Export to	Ireland, Singapore, Indonesia, Ukraine, Saudi Arabia, Spain, Canada, USA, Brazil, Thailand, Korea, Italy, India, Egypt, Oman, Malaysia, Kuwait, Canada, Viet Nam, Peru, Mexico, Dubai, Russia, etc
Package	Standard export seaworthy package, or as required.
Application	Widely used in petroleum, foodstuff, chemical industry, construction, electric power, nuclear, energy, machinery, biotechnology, paper making, shipbuilding, boiler fields. Pipes also can be made according to the customer's required.
Contact	If you have any questions, please feel free to contact me.
Container size	20ft GP:5898mm(Length)x2352mm(Width)x2393mm(High) 24-26CBM 40ft GP:12032mm(Length)x2352mm(Width)x2393mm(High) 54CBM 40ft HC:12032mm(Length)x2352mm(Width)x2698mm(High) 68CBM

Grade	C	Si	Mn	P	S	Ni	Cr	Mo
201	≤0 .15	≤0 .75	5. 5-7. 5	≤0.06	≤ 0.03	3.5 -5.5	16 .0 -18.0	-
202	≤0 .15	≤l.0	7.5-10.0	≤0.06	≤ 0.03	4.0-6.0	17.0-19.0	-
301	≤0 .15	≤l.0	≤2.0	≤0.045	≤ 0.03	6.0-8.0	16.0-18.0	-
302	≤0 .15	≤1.0	≤2.0	≤0.035	≤ 0.03	8.0-10.0	17.0-19.0	-
304	≤0 .0.08	≤1.0	≤2.0	≤0.045	≤ 0.03	8.0-10.5	18.0-20.0	-
304L	≤0.03	≤1.0	≤2.0	≤0.035	≤ 0.03	9.0-13.0	18.0-20.0	-
309S	≤0.08	≤1.0	≤2.0	≤0.045	≤ 0.03	12.0-15.0	22.0-24.0	-
310S	≤0.08	≤1.5	≤2.0	≤0.035	≤ 0.03	19.0-22.0	24.0-26.0
316	≤0.08	≤1.0	≤2.0	≤0.045	≤ 0.03	10.0-14.0	16.0-18.0	2.0-3.0
316L	≤0 .03	≤1.0	≤2.0	≤0.045	≤ 0.03	12.0 - 15.0	16 .0 -1 8.0	2.0 -3.0
321	≤ 0 .08	≤1.0	≤2.0	≤0.035	≤ 0.03	9.0 - 13 .0	17.0 -1 9.0	-
630	≤ 0 .07	≤1.0	≤1.0	≤0.035	≤ 0.03	3.0-5.0	15.5-17.5	-
631	≤0.09	≤1.0	≤1.0	≤0.030	≤0.035	6.50-7.75	16.0-18.0	-
904L	≤ 2 .0	≤0.045	≤1.0	≤0.035	-	23.0·28.0	19.0-23.0	4.0-5.0
2205	≤0.03	≤1.0	≤2.0	≤0.030	≤0.02	4.5-6.5	22.0-23.0	3.0-3.5
2507	≤0.03	≤0.8	≤1.2	≤0.035	≤0.02	6.0-8.0	24.0-26.0	3.0-5.0
2520	≤0.08	≤1.5	≤2.0	≤0.045	≤ 0.03	0.19 -0. 22	0. 24 -0 . 26	-
410	≤0.15	≤1.0	≤1.0	≤0.035	≤ 0.03	-	11.5-13.5	-
430	≤0.1 2	≤0.75	≤1.0	≤ 0.040	≤ 0.03	≤0.60	16.0 -18.0	-