Welded steel enclosed tubes of special cross section - description
Longitudinally welded thin-walled section tubes are made of hot-rolled or cold-rolled steel strips. HF induction welding produces excellent homogeneous joint with a minimal heat affected zone. Quality parameters of welded sections tubes are specified in CSN standards.
Specifications:
Welded steel enclosed tubes of special cross section are supplied in CSN standards stated in size tables.
Material quality:
Offer of steels by:
| EN 10305-3 | E155, E190, E195, E220, E235, E260,E275, E320, E355, E370, E420 |
| EN 10305-5 | E155, E190, E195, E220, E235, E260,E275, E320, E355, E370, E420 |
| ČSN | 11320, 11343 |
| DIN | St12, USt34-2 |
| GOST | 08kp |
Profile and size program:
download
Surface finish:
Depending on production technology and base material, the section tubes are supplied:
- oxidized
- bright
Surface defects and scratches smaller than the tolerance limit of the wall thickness are allowed. Even though the external collar of the weld has been removed the seam may be still visible. The size of the inner collar depends on the wall thickness and meets standard.
Tolerances dimensions:
| Dimensions A, B, C | Tolerances | |||
| more then [mm] | up to [mm] | outer dimensions [mm] | wall thickness [mm] | straightness [mm/1m] |
| - | 50 | ± 0,5 | t ± 10% | 3 |
| 50 | 100 | ± 1,0 | t ± 10% | 3 |
| 100 | výše | ± 1,2 | t ± 10% | 3 |
Lengths and tolerances:
| The range of lenghts | Lenghts [m] | Tolerances [mm] |
| Manufactured | 4 - 7 | |
| Approximate | 4 - 7 | ± 500 |
| Precise/td> | 4 - 7 | + 100 |
| Service | 0,3 - 2 | ± 0,5 |
Unless otherwise agreed, the ends of section tubes are supplied with cutting burrs within the wall thickness scope.
Packing and designation:
The section tubes are supplied in band-blocked bundles up to 2000 kg. Each bundle is fitted with the producer's label containing the data as follows:
- size
- steel grade
- lengths
- heat number
- weight in kg, by agreement length in m and number of pieces
- customer
Upon request, the surface of the tubes is protected against atmospheric corrosion with a preserving agent. Special shaped sections can be delivered upon the customers' inquiries.
