compression, bending and shear, the strength is also divided into tensile strength, compressive strength, flexural strength and shear strength. There is often a certain between various strengths. Generally, 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, steel plate, 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, silicon steel sheets, or thin-walled steel pipes, and generally adopts ordinary closed warehouse, that is, the warehouse with roof, 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, thin-walled pipe, the internal and external surfaces need to be coated with anti rust oil before storage; Steel pipes with serious corrosion shall not be kept for a long time after rust removal and shall be used as soon as possible. With the development of economy, 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 goodSquare tube has a wide range of application fields. Its main field is the construction industry, which promotes the development of economic construction. Because the production process of square tube hole is different, the production design of square tube hole is also different. Next,In different environments, the use efficiency of square tubes is different. According to the quality of square tubes, we will conduct progressive research on them, we will make square tubes suitable for use. Then what is the role of shot blasting and sand blasting in each other's pipe? Next, let's introduce it to you.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.Qaratau,Hardness QB square hardness is a pointer to measure the hardness and softness of metal materials. At present, the hardness method is commonly used to measure the hardness in production. It uses the indenter with fixed geometry to measure the hardness value of the metal material surface tested under fixed load according to the degree of hardness.For structure: as pile driving pipe and bridge; pipe for wharf, road and building structure, marine pile driving pipe, etc.Special performance steel: A. stainless and acid resistant steel; b. Heat resistant steel: including oxidation resistant steel, heat strength steel and air valve steel; c. Electric heating alloy steel; d. Wear resistant steel; e. Low temperature steel; f. Electrical steel.

The difference between square pipe and seamless steel pipe the main feature of seamless steel pipe is no welding joint and can withstand large pressure. The product can be very rough as cast or cold drawn parts.High strength structural steel with carbon content of .% - .%, adding main alloy elements such as manganese, silicon, vanadium, niobium and titanium; Its total alloy content is %. According to the strength, it is divided into four levels: , , and MPa.Mechanical engineering, power plants, agricultural and chemical machinery, glass curtain walls, automobile chassis, airports boiler construction,ChilpansingoHow much is 80 galvanized pipe, highway railings, housing construction, pressure vessels, oil storage tanks, bridges, power station equipment, etc. Process classification: according to the production process, square tubes are divided into hot-rolled seamless square tubes,ChilpansingoSquare pipe galvanizing cost, cold drawn seamless square tubes, seamless square tubes and qb square tubes.Total quality management,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; )Hot dip galvanized square pipe is widely used, mainly in curtain wall, solar power generation support, construction, machinery and steel structure engineering, especially in curtain wall, machinery and construction. The effect of cold galvanized square tube is far from that of hot galvanized square tube; How to distinguish hot galvanized square pipe from cold galvanized square pipe?The appearance of fake and inferior square tubes often has pitting. Pockmarked surface is an irregular uneven defect on the surface of square lead pipe due to serious wear of rolling groove. Due to the pursuit of profit by fake and shoddy square tube manufacturers the rolling of rolling groove often exceeds the standard.

: it refers to the processing of square tube, which places metal in a closed Jane and applies pressure at the end to extrude the metal from the specified die hole to obtain finished products with the same shape and size. It is mostly used to produce non-ferrous metal materials. Square tube ferrous metal, steel and non-ferrous metal. Before introducing the classification of steel, briefly introduce the basic concepts of ferrous metal, square tube steel and non-ferrous metal.Product line,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.Square tube is a kind of square tube type. Many materials can form square tube body. It is used for what purpose and where. Most square tubes are steel tubes, decorative square tubes and building square tubes. Square tubes can be divided into seamless and welded joints. Seamless square tubes are formed from seamless circular tubes. 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 workChilpansingo,The principle of straightening machine is that a disc is divided into two sides to clamp round steel straight lines. Professional square tube, square rectangular tube, seamless square tube, galvanized square tube, galvanized tube, high price,ChilpansingoGalvanized square pipe 30, service, on-site settlement, honest operation! The edge is one with radius r and the other outer edge must be two equal diameters with radius R. The diameter of the reinforcement to be straightened is D, the hardness method is commonly used to measure the hardness in production. It uses the indenter with fixed geometry to measure the hardness value of the metal material surface tested under fixed load according to the degree of hardness.

and the center distance between them is adjusted to R + R + D.The technology of floating mandrel and square tube is gradually mature.Hardness QB square hardness is a pointer to measure the hardness and softness of metal materials. At present