SCH = schedule
Pipes are also called differently in common parlance. In practice we encounter descriptions such as:
Example:
Question from a relationship: stainless steel 2 inch pipe schedule 40
This refers to a stainless steel pipe with an external pipe diameter of 60,33 mm and a wall thickness of 3,91 mm
The question is, should this relationship have a seamless or a welded tube and what should be the quality and execution? In this example, it will often be a pickled execution, but many tube dimensions are also available in metal blank, ground and polished execution.
From the above you will understand that a lot of confusion can arise because there are many different pipe sizes, terms, descriptions and standards in circulation.
We therefore recommend that you only discuss the external tube size (pipe size), wall thickness and descriptions such as quality, finish, etc.
We supply various tube sizes. Are you looking for a specific tube size? Then take a look at our documentation group Semi-finished products or take a look at the handy A4 overview. Here you will find frequently used tube dimensions in INCH, DIN, ISO and ASTM sizes.
| EN | DIN | DESCRIPTION |
|
BC |
|
ANNEALED, PICKLED INSIDE AND OUTSIDE OR METAL BLANC |
| BD | ANNEALED, PICKLED INSIDE OR METAL BRIGHT, GROUND OUTSIDE | |
| CC | UNANNAMED, PICKLED INSIDE AND OUTSIDE OR BRIGHT METAL | |
| CD | UNANNAMED, PICKLED INSIDE OR METAL CLEAR, GROUND OUTSIDE | |
| W0 | d0 |
LONGITUDINAL SEAM WELDED TUBES, MADE FROM HOT-ROLLED SHEET OR STRIP (c1 or c2), UNANNED, BLANC METAL |
| W1 | d1 |
LONGITUDINAL SEAM WELDED TUBES, MADE FROM HOT-ROLLED SHEET OR STRIP (c1 or c2), UNANNAMED, PICKLED |
| W1A | d2 |
LONGITUDINAL SEAM WELDED TUBES, MADE FROM HOT-ROLLED SHEET OR STRIP (c1 or c2), ANNEALED, PICKLED |
| W1R | d3 |
LONGITUDINAL SEAM WELDED TUBES, MADE FROM HOT-ROLLED SHEET OR STRIP (c1 or c2), BRIGHT ANNEALED, BLANK METAL |
| WO | k0 |
LONGITUDINAL SEAM WELDED TUBES, MADE FROM COLD-ROLLED SHEET OR STRIP (h, m or n), UNANNED, BLANC METAL |
| W2 | k1 |
LONGITUDINAL SEAM WELDED TUBES, MADE FROM COLD-ROLLED SHEET OR STRIP (h, m or n), UNANNAMED, PICKLED |
| W2A | k2 |
LONGITUDINAL SEAM WELDED TUBES, MADE FROM COLD-ROLLED SHEET OR STRIP (h, m or n), ANNEALED, PICKLED |
| k3 |
LONGITUDINAL SEAM WELDED TUBES, MADE FROM COLD-ROLLED SHEET OR STRIP (h, m or n), BRIGHT ANNEALED, BLANK METAL |
|
| b | g |
BEAD ROLLING Rolling out a weld seam in a tube, creating a smooth surface both internally and externally. |
|
Example: d1g or k1g is an unannealed, pickled tube with a rolled weld seam. |
||
|
Example: W1Rb is a bright annealed tube made from cold-rolled strip with a rolled weld seam. |
||
| TC1 | PK1 | MECHANICAL TEST CATEGORY 1 |
| TC2 | PK2 | MECHANICAL TEST CATEGORY 2 |
Note: With the exception of the weld seam, the surface finish of the "k" versions is normally smoother than the "d" versions. This difference is due to the fact that the "k" versions are made from cold-rolled sheet or strip and the "d" versions from hot-rolled sheet or strip.
Annealing means subjecting a product or semi-finished product to a time-temperature cycle, with the aim of optimising the properties for the application or processing.
Well-known glow treatments are:
SOLUTION ANNEALING
A heat treatment of stainless steel in which the precipitated carbides go into solution and the
condition is stabilized by rapid quenching.
The residual stresses are also reduced during the treatment. A carbide is an intermetallic
compound between carbon and another element. Carbides are usually very hard.
BRIGHT ANNEALING
A heat treatment in an inert atmosphere so that no oxide skin is formed and the
material therefore remains 'blank'.
