Bright annealing is an annealing process performed in a vacuum or a controlled atmosphere containing inert gases (such as hydrogen). This controlled atmosphere reduces the surface oxidation to a minimum which results in a brighter surface and a much thinner oxide layer. Pickling is not needed after bright annealing since the oxidation is minimal. Since there is no pickling, the surface is much smoother which results in better resistance to pitting corrosion. The bright treatment maintains the smoothness of the rolled surface, and the bright surface can be obtained without post-processing. After bright annealing, the surface of the steel tube retains the original metallic luster, and a bright surface close to the mirror surface has been obtained. Under general requirements, the surface can be used directly without processing. For bright annealing to be effective, We do the tube surfaces clean and free of foreign matter before annealing. And we keep the furnace annealing atmosphere is relatively free of oxygen (if a bright result is desired). This is accomplished by removing nearly all gas (creating a vacuum) or by displacement of oxygen and nitrogen with dry hydrogen or argon。 Vacuum bright annealing produces extremely clean tube. This tube meets the requirements for ultra high purity gas supply lines such as internal smoothness, cleanliness, improved corrosion resistance and reduced gas and particle emission from the metal. The products are used in precision instruments, medical equipment, semiconductor industry high purity pipeline, automobile pipeline, laboratory gas pipeline, aerospace and hydrogen industry chain (low pressure, medium pressure, high pressure) Ultra high pressure (UHP) stainless steel pipe and other fields. We also have over 100,000 meters of tube inventory, which can meet customers with urgent delivery times.

UNS	ASTM	EN
S30400/S30403	304/304L	1.4301/1.4307
S31603	316L	1.4404
S31635	316Ti	1.4571
S32100	321	1.4541
S34700	347	1.4550
S31008	310S	1.4845
N08904	904L	1.4539
S32750		1.441
S31803		1.4462
S32205		1.4462

Chemical and petrochemical/ Power and energy/ Heat exchanger manufacturing/ Hydraulic and mechanical systems/ Clean gas transpotationASTM A213 /ASTM A269/ASTM A789/EN10216-5 TC1 or as per requirements.

Production Standard	Internal Roughness			O.D Surface	Hardness max
	Type 1	Type 2	Type 3	Type	HRB
ASTM A269	Ra ≤ 0.35μm	Ra ≤ 0.6μm	No request	Mechanical Polish	90

Cold rolling / Cold drawing/ Annealing.Each single tube capped on both ends, packed in clean single-layer of bags and final into wooden case.