Steel pipe 830mm, Dnepropetrovsk region.

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Electrowelded pipe: description and characteristics
In accordance with GOST 10704-91, electrowelded steel pipes are produced with an outer diameter of 10 to 1420 mm and a wall thickness of 0.8–30 mm. They can have a measured or unmeasured length, which is strictly stipulated by this standard, and is equal to unmeasured rolled metal, not less than:
• 2.0 m for pipes with a diameter of up to 30 mm;
• 3.0 m – for products from 30 to 70 mm;
• 4.0 m, if the outer diameter is 70 - 152 mm;
• 5.0 m for pipe profiles over 152 mm in diameter.
The measured length of a round electrowelded pipe according to this GOST can be equal to:
• 5.0 – 9.0 m with a diameter of up to 70 mm;(//tractor-service.com)
• 6.0 – 9.0 m for rolled pipes from 70 to 219 mm in diameter;
• 10.0 - 12.0 m, if the outer diameter is 219 - 630 mm.
On the modern rolled metal market, you can buy electrowelded pipe of the following types (by type of heat treatment):
• thermally treated over the entire volume or only on the welded connection;
• hot-induced;
• thermally untreated.
For the production of welded pipes, a strip is used - a steel strip or rolled sheet, which acts as a basis. Giving the necessary shape to steel electrowelded pipes is carried out by bending the sheet with the use of special machines. Then the bent sheet is welded parallel or in a spiral.

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