Nikolaev pipe steel seamless cold-smoked, hot-smoked steel st20, st45 6-630 mm (Metallobaza) delivery, cutting

Seamless pipes are a type of rolled metal, the production technology of which provides for the absence of any seams along the entire length of the products. For a longer service life, as well as from an aesthetic point of view, the steel pipe is often painted in the desired color. To give more attractiveness, it can be covered with a layer of chrome. The cross-sectional shape of the pipes can also be different: drop-shaped, hexagonal, oval, flat-oval, with hollow ribs. Given that seamless pipes are most often made of carbon steel, they need to be protected from corrosion. This is achieved by conventional painting or by galvanizing the surface. In conditions where it is necessary to reduce the heat transfer of the pipe, for example, when transporting water or other substances in the heating system, the pipes can be additionally treated with a special insulating material. According to the shape of the section, steel pipes are divided into round and profile. In turn, profiles are divided into square, rectangular, oval, flat-oval, and so on. Steel pipes differ in the way they are made: electric-welded - straight-seam and spiral-seam, used for water pipes, gas pipelines, heating systems and structural parts; seamless - not having a weld or other connection. They are made by rolling, forging, pressing or drawing. They have found wide application: for the manufacture of main pipelines, for mechanisms for geo-prospecting for oil and gas. Steel pipes are divided by class: water and gas pipelines (VGP) GOST 3262-75. electric welded: straight seam GOST 10704-91, GOST 10705-80, GOST 10706-76; spiral stitch GOST 8696-74; for main oil and gas pipelines GOST 20295-85. profile: square GOST 8639-82, rectangular GOST 8645-68, oval GOST 8642-68 and GOST 8644-68. seamless: hot-formed GOST 8732-78, cold-formed GOST 8734-75, as well as special-purpose, made according to various specifications, TU. To increase resistance to corrosion, water and gas pipes and electric welded pipes can be coated with a layer of zinc both inside and outside (galvanized pipes). In addition, they distinguish: a hose is a flexible pipe. Flexible pipes (hoses) are: ordinary, reinforced (reinforced), corrugated. For connection and building up, a segment of an ordinary (rigid) pipe of a smaller diameter is used: a branch pipe, a fitting. Seamless pipe is a round, square or rectangular steel pipe made without seams. Seamless steel pipe is made without coating by perforating a steel block or a solid pipe billet. Then the finished product is formed by hot-rolled, cold-rolled or cold-drawn method - a seamless pipe. Seamless steel pipe has a hollow profile and is used as a pipe for transporting liquids, including VGP pipes. Compared to hard steel (high silicon content), ordinary steel pipe is lighter in weight but has the same bending and torsional strength. Pipes made from such steel are widely used for the manufacture of structures, mechanical parts for scaffolding and for drilling oil wells. Systems for the production of seamless and welded pipes can only supply certain minimum diameters. There are various pipe processing methods: The stretching-reducing mill has a stand with several pairs of rollers, which reduce not only the diameter of the warm pipe, but also the wall thickness. Cold rolling works with a mandrel that, on the one hand, serves as a support to reduce the wall thickness, and on the other hand, determines the pipe diameter and cross-sectional shape. Seamless pipes are made from complete, pre-perforated or drilled blocks or heated billets. At the first stage, a short thick-walled cavity is created; at the second stage, it is stretched, forming a finished pipe. In the stepwise process of transverse rolling of pipes with an outer diameter of 50–660 mm, a heated round block in the transverse rolling mill is driven by two rolls rotating in the same direction with axes inclined to the horizontal and mutually aligned. The core is stretched over a rod with a profiled head, which levels the inner surface. The billet is then stretched to form a tube in a rolling mill with constant rotation. In the process of manufacturing cone plugs for pipes with an outer diameter of 60-324 mm, inclined cones or disks, similar to inclined rollers, pierce a round block. The resulting billet is drawn into a tube at a sleeve rolling mill. The plug is a fixed frame between a pair of calibration rollers. The pipe blank is pushed into the passage, caught by the rollers and pulled onto the stopper. The process is repeated until the required size is reached. In a continuous process, for pipes with an outer diameter of 20–168 mm, a hollow shape is formed during transverse rolling, rolled over the mandrel bar, and loosened to such an extent that the finished pipe can be easily peeled off.