Bright Annealed Tube / Pipe

Effects of bright annealing (BA) on enhancing formability of stainless steel 304 316 321 tube in a tube hydroforming (THF) process were studied.

The tube material was the metastable austenitic stainless steel 304 with an initial thickness of 0.5 mm and an outer diameter of 31.8 mm.

Both FEA and experimental results showed that THF process of the investigated part alone failed to achieve desired tube expansion of

the diameter of 50.8 mm without severe fracture. Thus, a heat treatment process, also known as bright annealing (BA),

which caused little to none oxide on the surface of annealed tube, was considered.

Designed for critical and purity applications such as semiconductor manufacturing, Max Stainless Steel’s high purity tubing delivery of gases, chemicals and solvents,

or use in ultra High vacuum piping for reducing out gas rate.

From advanced manufacturing processes, including special cold drawing and cold pliger not just precision for sizes,

but also enhance material substrutes density by cold pilger process. The ID is cold drawing to a 15Ra(0.4µm) finished,

by Hydrogen bright annealed process removed tube lubrication and optimum anti-corrosion ability, stress free,

good mechanical properties follow by precision cleaning process to removed any residual contaminants,

simulated natural light inspection at both ends verifies cleaning before the tubes are nitrogen purged and capped.

Bright Annealing available in a wide range of stainless steels, are characterized by tight tolerances,

and the inside surface of the tubes is free of oil, grease and other particles. This ensures, for example,

an optimized and even flow of liquids and gases from the sensor to the measuring instrument.

We have 4 Sets of three roller Precision Cold Rolling Machines using highly polished rollers

in touch with the stainless steel surface and control the velocity of the pilger machine to ensure the smoothness and brightness.

Selected the best quality stainless steel round bar, clean and smooth on outside surface and inside surface.

Withstand high pressure,no deformation after cold bending, no crack and break after flattening and flaring etc.
Technical Data:
1) Description:
Bright Annealed Tubes | BA Tube
2)Specification:
United States: ASTM A213 / A269
3) Reference Sizes:
6.35×0.89, 9.53×0.89, 12.7×1.24, 19.05×1.65, 25.4×2.11, etc
Special sizes can be made to order.
4) Advantages:
a. good dimensional accuracy
O.D.: +/-0.05mm, W.T.: +/-0.05mm
b. excellent surface roughness
outside surface: Ra < 0.6um, inside surface: Ra < 0.3um

Our bright annealed tubes are widely used in the fields of precision instruments,

oil & gas service, precise mechanical parts, semiconductor industry, bio-pharmaceutical, etc
Textile Industries
Precision instruments and parts
Medical eauipment apparatus
Electronic and electric appliance
Automatic apparatus
Opto-electrical and semi-conductor

Main Testing Terms and Procedure:

• 1. Heat Treatment and Solution Annealing / Bright Annealing
• 2. Cutting to required length and deburring;
• 3. Chemical Composition Analysis Test With 100% PMI and One tube from each heat by Direct Reading Spectrometer
• 4. Visual Test and Endoscope Test for Surface Quality Test
• 5. 100% Hydrostatic Test and 100% Eddy Current Test
• 6. Ultrasonic Test subject to the MPS (Material Purchase Specification)
• 7. Mechanical Tests includes Tension Test, Flattening Test, Flaring Test, Hardness Test
• 8. Impact Test subject to Standard request
• 9. Grain Size Test and Intergranular Corrosion Test
• 10. Ultrasoic measuring of Wall Thickness

Marking & Packing

• Marking according to MPS and Standard
• Stainless Steel Tubes Ends with Caps according to PO
• In Plywood Cases