According to metallographic classification, the annealed state of square tube: A. hypoeutectoid steel (ferrite + pearlite); b. Eutectoid steel (pearlite); c. Steel precipitation through a common square tube (pearlite + cementite); d. Ledeburite steel (pearlite + cementite).High quality steel (P & le; .%, S & le; .%)portland ,At the same time,portland 40 galvanized square pipe thickness,portland Q345D square tube,portland ninety-five, hanging heating shall be carried out during heating to reduce quenching deformation. For high-precision guide rail, I'll introduce it to you.Functional index analysis of qb square tube - mechanical function of plastic square tube. Solid bending, as the name suggests, is to compact the bending. During real bending, the inner and outer rollers and the inner and outer walls of the pipe blank are compacted in both directions.Kafr Nabl,Compared with other welding, square pipe welding has many advantages, mainly because of the exothermic reaction, the material only needs to be heated below the melting pointThe inspection items, sampling quantity, sampling position and test of square tube shall be in accordance with the provisions of corresponding product standards. With the consent of the demander, hot-rolled square tubes can be sampled in batches according to the rolled root array. special shaped square pipe is the general name of square pipes with other cross-section shapes except circular pipe. According to the different cross-section shape and size of steel pipe, it can be divided into special-shaped square pipe with equal wall thickness (code D), special-shaped square pipe with unequal wall thickness (code BD) and special-shaped seamless steel pipe with variable diameter (code D) These special-shaped large-diameter qb square tubes are widely used in various structural parts, tools and mechanical parts. Compared with circular tubes, special-shaped tubes generally have large moment of inertia and section modulus, and have large bending and torsion resistance, which can greatly reduce the structural weight and save steel. Square tubes are an indispensable part of construction work

Square tube is an essential material for the construction and Realization of industrialization. It is widely used and has a wide variety. According to different section shapes, square tube is generally divided into sections, plates, pipes and metal products. In order to facilitate the production, ordering and supply of square tube and do a good job in operation and management, it is also divided into heavy rail, light rail, large section steel, high-quality section steel small section steel and square tube cold bending Section steel, wire rod, medium and thick steel plate, sheet steel, electrical silicon steel sheet, strip steel, seamless steel pipe, welded steel pipe metal products, etc.Electrochemical polishing: long specular gloss, stable process, less pollution and good durability. Suitable for mass production, it is mainly applied to high-grade products, imported products and public service products. Its processing technology is stable and the operation is simple.When sand blasting or manual mechanical derusting is used, due to the falling off of the oxide scale of the galvanized square pipe, the metal on the surface of the galvanized square pipe is directly exposed in the air. If a primer is not applied in time, the surface of the galvanized square pipe is easy to rust again, affecting the adhesion of the paint film. I am engaged in all kinds of square tubes, square rectangular tubes, seamless square tubes, galvanized square tubes, galvanized tubes and other materials all year round. I operate in good faith. Welcome to call! As the paint is a time-effective material, the overstock of inventory is easy to expire. Therefore the main indexes of the paint must be rechecked before use, and the paint can be used only when the results meet the standards.Administration,Change to square pipe: generally, the strip steel is unpacked, leveled, crimped and welded to form a round pipe, then rolled into a square pipe from the round pipe, and then cut into the required length. Stage ( & mdash; )The surface of galvanized square pipe treated by sand blasting, shot blasting or pickling process is relatively clean, and the oxide scale and rust are removed, which improves the adhesion of the coating. When the installation site unconditionally adopts sand blasting and shot blasting, manual and mechanical derusting can be adopted, but the derusting quality level must be reached.Classification of square tube steel is iron carbon alloy with carbon content of square tube between .% - %. In order to ensure its toughness and plasticity, the carbon content generally does not exceed %. In addition to iron and carbon, the main elements of steel also include silicon, manganese, sulfur, mainly including the following: square tubes are classified into ordinary steel according to quality (P & le; .% etc. There are various classifications of steel and square tubes, S & le; .%)

Steel used & mdash& mdash; Such as bridge steel, ship steel, boiler steel, pressure vessel steel, agricultural machinery steel etc.Where can I find it?,High pressure oil pipe for diesel engine (gb-) is a cold drawn square pipe for high pressure pipe of diesel engine system.Galvanized qb square pipe for low pressure fluid transmission, Standard No.: gbt-. The representative material is the same as above. It is mainly used to transport low pressure fluids such as water, gas, air, oil and heating hot water or steam. The surface of square pipe adopts hot galvanizing or cold galvanizing process.The difference between hot-dip galvanized square pipe and cold-dip galvanized square pipe is mainly from the following aspects: the appearance of hot-dip galvanized square pipe is slightly rough compared with cold-dip galvanized square pipe; The appearance of cold galvanized square pipe is smooth and bright.portland ,In this period, the technology of continuous rolling pipe was not mature.High pressure oil pipe for diesel engine (gb-) is a cold drawn square pipe for high pressure pipe of diesel engine system.Structural stainless steel square pipe (gbt-) is a hot-rolled (extruded, expanded) and cold drawn (rolled) square pipe made of stainless steel for corrosion-resistant pipes, structural parts and parts widely used in chemical, petroleum, light textile, machinery and other industries.