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

The weakest point of a welded pipe is the seam. Despite the constant improvement of technologies, due to additional heating during welding, the metal structure along the joint becomes brittle, and the weld itself has a looser molecular structure, subject to corrosion destruction. Steel seamless pipes do not have such a flaw; a monolithic cylindrical shape serves as a reliable protection against leaks. The main purpose of a seamless pipe is high-pressure pipelines or the transport of hazardous substances in industrial facilities. When a leak or rupture could threaten the safety of life or the environment. In domestic engineering networks, there are no loads that a straight-seam pipe could not withstand, however, the absence of a seam increases the service life, durability and reliability, for example, of gas equipment in a private house. Seamless pipes can be bent without loss of quality, so they are used for the manufacture of coils, spirals and bent bends. Applications of seamless steel pipes: High pressure gas and oil pipelines; Chemical pipelines for transportation of solutions of acids, alkalis, toxic gases; Coils and spirals of industrial heat exchangers, water heaters; Systems with closed circuits; Extraction of gases and combustion products from blast furnaces; Details of piston mechanisms; Pipeline accessories; Foundation piles for power transmission lines and other metal structures. The main advantage of a seamless body is tightness, resistance to tearing and corrosion, since all adverse factors associated with a welded joint are excluded: residual stresses, microheterogeneity, sagging, loss of elasticity. Classification of seamless pipes Products are made of carbon and alloy steels, especially stainless steels. Manufacturers use two methods: Cold-rolled GOST 8733-74; Hot-rolled GOST 32528-2013 (GOST 8734-75 is valid with clarifications). Hot-rolled pipes are obtained from hot cylindrical billets; heating modes from 900 to 1270 Co are used for different steels. During hot rolling, the structure of the metal retains its elasticity, compacts, but it is impossible to obtain a thin-walled material. The cold method includes several stabilizing annealings, during which the metal grain is ground, and residual stresses are removed, the structure becomes homogeneous and strong. The deformation is carried out in a cooled state, but the metal in the rolling machine is strongly heated due to friction. This method allows the production of high-precision products with thin walls. Manufacturers produce tubular products of fixed or random length, length parameters can be agreed with the customer. GOST 8733-74 establishes supply groups with standardized criteria: · B – mechanical properties; B - chemical composition; D - chemical composition and mechanical characteristics after heat treatment; D - hydraulic pressure; E - mechanical properties after special heat treatment. In many types of production, in construction and in other areas, it is impossible to do without pipelines of various types. Today, the customer can choose the type of pipe from a large list. In many situations, a seamless pipe will be the best option, given the reliability, durability and other characteristics. What is a seamless pipe? In simple terms, pipes can be solid (seamless) and consisting of various elements connected by welding. Seamless steel pipes are created by heating a billet of a certain diameter. By heating the workpiece, it can be rolled up, bent, or perform other necessary actions with it. Accordingly, given the technology for creating such a pipe, they can be: Cold-formed; Hot-formed; Heat-deformed. Accordingly, seamless pipes do not have a welded seam - this guarantees their integrity and the same metal density throughout the entire section. Such pipes are also relatively light in weight. For operation in those conditions when it is necessary to distill substances at high speed and in large volume, this design is very important. Indeed, in the presence of seams, a leak or a breakthrough of the pipe in one or more sections can occur at any time. Seamless Steel Pipe Standards Of course, as in many other areas, among steel pipes there are standards that allow you to quickly make a choice of material depending on the operating conditions. The main standards include: ASTM A 106 - these pipes are designed for use at high temperatures, have an average wall thickness; ASTM A 333 - these pipes are used at low temperatures, their walls also have an average thickness; ASTM A 335 is thin alloy steel pipe used at high temperatures; ASME/ANSI B 36.10 - These pipes can be used at both high and low temperatures and pressures.