Introduction
904L Super austenitic stainless steel of low carbon and high nickel, molybdenum austenitic stainless and acid-resistant steel, for the introduction of France h • S the company's proprietary material.
---a good change activation-deactivation capabilities, excellent corrosion resistance, non-oxidizing acids such as sulfuric acid, acetic acid, formic acid, phosphoric acid and has good corrosion resistance, in the neutral medium containing chloride ions has a good resistance to pitting, has a good resistance to crevice corrosion and stress corrosion performance.
---Applies to 70 ℃ the following kinds of concentrated sulfuric acid at atmospheric pressure under any concentration, temperature of acetic acid and formic acid and acetic acid corrosion resistance is also very good.

Technical Parameter

904L stainless steel
Standard	Grade	Chemical Composition %	Technique	Yied strength Mpa	Tensile strength Mpa	Elongation %	Hardness
GB	0Cr20Ni25SiMn4.5Cu	C≤0.02，Mn≤2.00， Si≤1.00，P≤0.045， S≤0.035，Cr 19.0~23.0, Ni 23~28,Mo 4~5, Ni 23~28, Cu 1.0~2.0	Annealed, hot rolled/ cold rolled	≥220	≥490	≥36	HV≤150
USA	N08904
JIS	/
German	1.4539

Nominal diameter		Outside (mm)	Nominal wall thickness
			SCH5 S			SCH1 0S			SCH2 OS
N.B	NPS		Wall (mm)	WEIGHT （kg/m）		Wall (mm)	WEIGHT （kg/m）		Wall (mm)	WEIGHT （kg/m）
				Grade			Grade			Grade
				TP304 TP304L	TP316 TP316L		TP304 TP304L	TP316 TP316L		TP304 TP304L	TP316 TP316L
8	1/4"	13.72				1.65	0.5	0.5	2.24	0.64	0.64
10	3/8"	17.15				1.65	1.65	0.64	2.31	0.85	0.86
15	1/2"	21.34	1.65	0.81	0.81	2.11	1.01	1.02	2.77	1.28	1.29
20	3/4"	26.67	1.65	1.03	1.03	2.11	1.29	1.3	2.87	1.7	1.71
25	1"	33.4	1.65	1.31	1.31	2.77	2.11	2.13	3.38	2.53	2.54
32	1 1/4"	42.16	1.65	1.67	1.68	2.77	2.72	2.74	3.56	3.42	3.45
40	1 1/2"	48.26	1.65	1.92	1.93	2.77	3.14	3.16	3.68	4.09	4.11
50	2"	60.33	1.65	2.41	2.43	2.77	3.97	4	3.91	5.5	5.53
65	2 1/2"	73.03	2.11	3.73	3.75	3.05	5.32	5.35	5.16	8.72	8.78
80	3"	88.09	2.11	4.56	4.59	3.05	6.52	6.56	5.49	11.4	11.5
90	3 1/2"	101.6	2.11	5.23	5.23	3.05	7.49	7.54	5.74	13.7	13.8
100	4"	114.3	2.11	5.9	5.9	3.05	8.45	8.51	6.02	16.2	16.3
125	5"	141.3	2.77	9.56	9.56	3.4	11.7	11.8	9.55	22	22.1
150	6"	168.28	2.77	11.4	11.4	3.4	14	14.1	7.11	28.5	28.7
200	8"	219.08	2.77	14.9	14.9	3.76	20.2	20.3	8.18	43	43.2
250	10"	273.05	3.4	22.8	22.8	4.19	28.1	28.2	9.27	60.9	61.3
300	12"	323.85	3.96	31.6	31.6	4.57	36.3	36.6	9.52	74.5	75
350	14"	355.6	3.96	34.7	34.7	4.78	41.8	42
400	16"	406.4	4.19	42	42	4.78	47.8	48.1
450	18"	457.2	4.19	47.3	47.3	4.78	53.9	54.2
500	20"	508	4.78	59.9	59.9	5.54	69.3	69.8
550	22"	558.8	4.78	66	66	5.54	76.4	76.8
600	24"	609.6	5.54	83.4	119.5	6.35	95.4	96
750	30"	762	6.35	119.5	119.5	7.92	148.8	149.7

Seamless steel pipe
Steel ingots or solid tube through the perforation of the capillary, and then by hot-rolled, cold-rolled or cold dial made. with hollow cross-section, a large number of pipes for the transmission fluid. is generally molten state of the molten steel through the annular slit back out and then processed by the tensile molding process, so there is no weld. In terms of performance, especially pressure on the ability of welded steel pipe has greatly improved, it is often used for high-voltage equipment. Such as hydraulic equipment, piping connections.

Welded pipe
A steel or steel plate bending deformation into a circular and then welded into the surface of the steel pipe joints. Welded pipe used in the blank is steel or strip.The welding seam of welded steel pipe is the weak link, and the quality of weld is also the main factor affecting its overall performance. Welded steel pipe in the north of the China people living in general have had water pipes or heating pipes in the winter was the experience of cold explosion, where the explosion is generally weld.

Application
* Petroleum and petrochemical equipment, petrochemical equipment in the reactor.
* Sulfuric acid storage and transportation equipment, such as heat ex-changers, and so on.
* Power plant flue gas desulfurization equipment, mainly using parts: absorber Tower, flue, stall doors, trim, sprinkler systems, etc.
* Organic acid scrubber and the fans in the system.
* Sea-water treatment plant, seawater heat ex-changers Equipment for the paper industry, sulfuric acid and nitric acid equipment, pharmaceutical industry of sulfuric acid and other chemical equipment, pressure vessels, food equipment.
* Pharmaceutical factory: centrifuge, reactor, and so on.
* Plant foods: soy sauce pots, cooking wine, salt shakers, equipment and dressing.