HSAW pipes

HSAW pipes is an important indicator to measure quality of steel pipe.

HSAW pipes

To measure the hardness of the steel pipe is generally used three Brinell, Rockwell, Vickers hardness index.

Brinell hardness of the steel pipe: brinell hardness is widely used in steel standard and often go through indentation diameter to represent the hardness of the material, both intuitive and convenient. But for hard or thin steel pipe does not apply.

Rockwell hardness of the steel pipe: steel pipes Rockwell hardness test is the sames as brinell hardness test using indentation test method. Different is that it is measuring the depth of the indentation. Rockwell hardness of the steel tube test is a very wide application, including HRC steel pipe standards after the Brinell hardness of HB. Rockwell hardness is applicable to the determination of extremely soft to extremely hard metal material, it makes up for the Brinell method is not higher than the Brinell method is simple, can be directly read from the dial of the hardness machine hardness value. However, because of its small indentation hardness values ​​as Brinell method is accurate.

Vickers hardness of the steel pipe: steel pipes Vickers hardness test is also a indentation test method for the determination of a thin metal material and the surface layer hardness. It has a Brinell, Rockwell law of the major advantages to overcome the basic shortcomings, but not as good as the Rockwell method is simple, Vickers method is rarely used in the steel pipe standards.

What is LSAW and HSAW?

LSAW and HSAW are variants of SAW (submerged arc welded) pipes. The difference between them is the way they are welded. In LSAW pipes, the welding is longitudinal, which means that steel (hot rolled coil plate) is rolled into a pipe and the seam is welded longitudinally. In the HSAW type, steel coils are welded spirally, like a helix, so that the coil (strip) assumes the shape of a pipe. SAW pipes are used mainly in oil and gas transportation.

Helical submerged arc welding (spiral) steel pipe is the full name of hsaw pipe, to the strip into the welded pipe unit, the multi-roll rolling, the strip gradually rolled up to form a circular tube with an open gap, adjust the reduction of squeezing roller so that the weld gap control in 1 - 3mm, and make both ends of the weld flush. Spiral welded pipe is formed by forming the material strip spiral molding, through internal and external submerged arc welding, thus producing different specifications of the spiral welded pipe.

Helical submerged arc welding (spiral) steel pipe has many advantages over other welded pipe:

(A)The pipe has two overlapping inner and outer spiral weld, play a role in increasing the rigidity, bearing pressure also increased accordingly.

(B)The use of submerged arc welding process, slag protection effect. Therefore, it has good impact toughness and low temperature performance.

(C)The use of the same width of the strip can produce different diameters and lengths of steel, and straightness good. Easy to adjust, precise size, without sizing and straightening after welding.

Weled steel pipe specification, Standard and identification

Welded steel pipe (steel pipe manufactured with a weld) is a tubular product made out of flat plates, known as skelp, that are formed, bent and prepared for welding.