According to smelting classification and furnace type, A. open hearth steel: (a) acid open hearth steel; (b) Alkaline open hearth steel.The technology of floating mandrel and square tube is gradually mature.Zotmir,The cutting surface of the square tube shall be true circle, and the cutting line shall be at right angles to the axis of the square tube. Excessive force is the reason for cutting the square tube into flat or oval, so the square tube should be cut with appropriate force.Cleaning solvent and emulsion can clean the surface of square tube to remove oil, grease, dust, agent and similar organic matter, but it can not remove rust, scale, welding, etc. on the surface of square tube, so it is only used as an auxiliary means in production.Amnat Charoen,High quality steel (P & le; .%,Zotmir25 galvanized round pipe,ZotmirGalvanized square steel pipe, S & le; .%)Section shape classification square tubes are classified according to section shape: simple section square tubes & mdash& mdash; Square tube, rectangular tube and complex section square tube & mdash& mdash; Surface treatment classification of flower shaped square pipe, open square pipe, corrugated square pipe and special-shaped square pipe square pipe is divided into hot-dip galvanized square pipe, oil coated square pipe and pickling square pipe according to surface treatment. Square pipe is classified according to purpose & mdash& mdash; Square tubes for decoration, machine tools and equipment, machinery industry, chemical industry, steel structure shipbuilding, automobile, steel beam and column and special purpose are classified by wall thickness & mdash& mdash; Super square tube, square tube and thin-walled square tube plasticity refers to the ability of metal materials to produce plastic deformation (deformation) without deformation under load.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.

There are many processing technologies for square tubes. I won't introduce the specific processing technology here. We only know about the processing technology of each other's tubes. We may have insufficient understanding of its heating technology. Next, I'll give you a detailed introduction to the heating technology of the lower tubes.Steel with chromium content of more than % in steel and high corrosion of external medium (acid, alkali salt) is called square pipe. According to the condition in steel, square tubes can be divided into martensite, ferrite, austenite and ferrite & mdash; Austenite type precipitation hardening square tube, according to the standard gb & mdash; regulations, a total of regulations.The reason why the surface of fake and shoddy materials is easy to crack is that its blank is adobe with many air holes. During the cooling process, the adobe has cracks due to the action of thermal stress,The reason why the surface of fake and shoddy materials is easy to crack is that its blank is adobe with many air holes. During the cooling process, the adobe has cracks due to the action of thermal stress, and there are cracks after rolling.Stage ( & mdash; )Engaged in square tube, square rectangular tube, seamless square tube, old brand galvanized tube, price advantage and quality guarantee! However, the Demander shall cut off the interface pipe when using it. The weight of short length and non fixed length products shall not exceed % of the total delivery. For qb square pipe with theoretical weight greater than kgm, it shall not exceed % of the total delivery. The bending degree of qb square pipe shall not be greater than mm per meter, and the total bending degree shall not be greater than .% of the total length. Galvanized qb square pipe for low-pressure fluid transmission, with standard number of gbt-. Representative materials: QA, qbqb, etc. It is mainly used for conveying water, gas, air, oil and heating hot water or steam, and its purpose is limited to general low pressure fluid.

According to smelting classification and furnace type, A. open hearth steel: (a) acid open hearth steel; (b) Alkaline open hearth steel.Quality risk,Square tube plays an important role in the rapid economic development. The functions of square tube are different, and its characteristics are also different. Square tube has strict standards. There are many welding processes and advantages of square tube. Let me show you the welding process and advantages of lower tube.Square tube failure. When the pipeline is erected, it is necessary to do a good job or directly use the square pipe. The reason for the corrosion of the pipeline is that the layer of the pipeline is damaged. Once the layer is separated from the pipe surface it will naturally cause failure.A. square tube structural steel: (a) high quality carbon structural steel; (b) Alloy structural steel; (c) Spring steel; (d) Easy cutting steel; (e) Bearing steel; (f) High quality structural steel for specific purposes.Zotmir,Ship carbon steel square pipe (gb-) is a carbon steel square pipe for ship class I pressure pipe system, class II pressure pipe system, boiler and superheater. It is a long-term business square pipe, square pipe, seamless square pipe, galvanized square pipe and galvanized pipe. Welcome to consult. The working temperature of carbon steel square pipe wall shall not exceed ℃, and the working temperature of alloy steel square pipe wall shall exceed ℃.Strength refers to the performance of metal materials under static load (excessive plastic deformation or fracture). Since the action modes of load include tension, compression, bending and shear, the strength is also divided into tensile strength, compressive strength, tensile strength is used as the basic strength indicator. Appropriate sites and warehouses shall be selected. The sites or warehouses for storing steel pipes shall be in clean and unobstructed places, away from factories and mines that produce harmful gas or dust. Weeds and sundries shall be removed on the site to keep the steel pipe clean; In the warehouse, it is not allowed to stack with acid, alkali, salt, cement and other materials that are corrosive to the steel pipe. Different types of steel pipes shall be stacked separately to prevent confusion and corrosion; Large section steel, rail, large-diameter steel pipe, forging, etc. can be stacked in the open air; Small and medium-sized section steel, wire rod, reinforcement, medium diameter steel pipe, steel wire and steel wire rope can be stored in a well ventilated shed, but they must be covered and padded; Some small steel pipes, steel sheets, steel strips, or thin-walled steel pipes, all kinds of cold-rolled and cold drawn steel pipes and high and corrosive metal products can be stored in the warehouse; The warehouse shall be selected according to geographical conditions, and generally adopts ordinary closed warehouse, that is, the warehouse with roof,ZotmirStrength of galvanized square pipe, enclosure, tight doors and windows and ventilation devices; The warehouse is required to pay attention to ventilation in sunny days, close and damp proof in rainy days, and often maintain a suitable storage environment. The principle of reasonable stacking and first in first stacking is to stack according to varieties and specifications under the condition of stable stacking and ensuring safety. Materials of different varieties shall be stacked separately to prevent confusion and mutual corrosion; It is forbidden to store articles that have corrosive effect on steel pipes near the stacking position; The bottom of the stack shall be padded high, firm and flat to prevent the material from moisture or deformation; The same kind of materials shall be stacked according to the warehousing order, so as to facilitate the implementation of the principle of first in, first out; The section steel stacked in the open air must be provided with wooden mats or strip stones. The stacking surface is slightly inclined to facilitate drainage. Pay attention to the straightness of the material placement to prevent bending and deformation; The stacking height shall not exceed m for manual operation, m for mechanical operation, and m for stacking width; A fixed channel shall be reserved between stacks, generally .m, and the access channel is generally ~ om depending on the size of materials and transportation machinery; The bottom of the stack shall be padded up. If the warehouse is cement floor, it can be padded up by .M; If it is muddy ground, it must be padded . ~ .m high. If it is an open site, the cement ground shall be padded with O & middot; ～O· m, . ~ . m higher than the sand and mud surface, the angle steel and channel steel shall be stacked in the open air, i.e. the mouth shall face down, and the I-beam shall be placed vertically. The i-groove surface of the steel pipe shall not face up to avoid ponding and rust. The packaging and protective layer of the protective materials shall be coated with agent or other plating and packaging before leaving the factory, which is an important measure to prevent material corrosion. Attention shall be paid to protection during transportation, loading and unloading and shall not be damaged, The storage period of materials can be extended, the warehouse shall be kept clean and the maintenance of materials shall be strengthened. Before warehousing, materials shall be prevented from being drenched or mixed with impurities. Materials that have been drenched or contaminated shall be wiped according to their properties such as steel wire brush for high hardness and cloth, cotton and other materials for low hardness; The materials shall be regularly after warehousing. If there is corrosion, the corrosion layer shall be removed; Generally, the steel pipe surface does not need to be coated with oil after being cleaned, but for high-quality steel, alloy steel sheet, alloy steel pipe, etc., all kinds of square tubes, rectangular tubes, seamless square tubes, galvanized square tubes and galvanized tubes have been recognized by the majority of customers for a long time. There are more and more counterfeit products on the market. In order to prevent being deceived when you are in square tubes, you need to know some knowledge about how to judge the authenticity of square tubes: & ldquo; We can judge by observing the surface and flatness of the square tube. If the surface of the square tube is relatively flat, it can reflect that the square tube is good. On the contrary, if the surface is not goodIf there is only a single plane weld the step-by-step back welding shall be adopted from the middle, that is, the arc of the section weld shall be terminated at the section arc.