Weld Seam Height
The outside weld bead of HF welded tube shall be removed completely i.e. flush with the outside surface of the tube.
The maximum heights of the external and internal weld seams shall otherwise be as given in the table below:
| Weld Finish |
Wall Thickness (T) < 8 Mm |
Wall Thickness (T) > 8 Mm |
| Finish A |
0.20 T + 0.5 |
T/3 |
| Finish B For D < 114.3 Mm |
0.06 T + 0.3 |
– |
| Finish B For D > 114.3 Mm |
0.05 T + 0.5 |
T/6 |
| Finish C |
0.15 |
– |
Tubes shall be delivered with one of the following weld bead finishes:
Finish A – Internal and external weld bead not removed
Finish B – External weld bead removed internal weld bead not removed
Finish C – Internal and external weld bead rolled or removed
Finish A shall not be used on HF welded tube
TIG Welding Stainless Steel Tubing
TIG welding (Tungsten Inert Gas Welding) is the most common method for welding stainless steel, whether manual or automatic welding, argon can be effectively isolated from the surrounding air which itself is not dissolved in the metal, and not metal reaction; the arc in the process of tungsten argon arc welding and automatic removal of the role of the surface oxide film.
TIG welding stainless steel tubing wall thickness range from 0.5 to 4.0 mm, tubes are produced without the addition of filler metal, welding two strip edges, TIG welding process provides high quality welding, after heat treated solution, welding bend is integrity with base metal.
Reference Standards:
| ASTM Specification |
| ASTM A249/A249M, ASME SA249/SA249M Welded Austenitic Steel Boiler, Superheater, Heat-Exchanger, and Condenser tubes |
| ASTM A269/A269M, ASME SA269/SA269M Seamless and Welded Austenitic Stainless Steel Tubing for General Service |
| ASTM A270/A270M, ASME SA270/SA270M Seamless and Welded Austenitic and Ferritic/Austenitic Stainless Steel Sanitary Tubing |
| ASTM A312/A312M, ASME SA312/SA312M Seamless and Welded Austenitic Stainless Steel Pipes |
| ASTM A789/A789M, ASME SA789/SA789M Seamless and Welded Ferritic/Austenitic Stainless Steel Tubing for General Service |
| ASTM A790/A790M, ASME SA790/SA790M Seamless and Welded Ferritic/Austenitic Stainless Steel Pipe |
| |
| German Standards |
| DIN 2463-1 Welded austenitic stainless steel tubes: dimensions and masses per unit length |
| DIN 17455 Welded circular stainless steel tubes with general quality requirements -Technical delivery conditions |
| DIN 17457 Welded circular austenitic stainless steel tubes subject to special requirements |
| |
| EN Standards |
| EN 10216-5 Welded Stainless Steel Tube |
| EN 10217-7 Welded steel tubes for pressure purposes - Technical delivery conditions - Part 7: Stainless steel tubes |
| EN 10296-2 Welded circular steel tubes for mechanical and general engineering purposes - Part 2: Stainless steel |
| |
| JIS-Standards |
| JIS G3448 Light Gauge Stainless Steel Tubes for Ordinary Piping |
| JIS G3459 Stainless Steel Pipes |
| JIS G3446 Stainless Steel Pipes for Machine and Structural Purposes |
| |
| Australian Standards |
| AS 1528.1 Tubes (Stainless Steel) and Tube Fittings for the Food Industry. |
