Strength refers to the performance of metal materials under static load (excessive plastic deformation or fracture). Since the action modes of load include tension, 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,GranadaDN125 galvanized square pipe, 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, enclosure, close and damp proof in rainy days, so as to facilitate the implementation of the principle of first in firm and flat to prevent the material from moisture or deformation; The same kind of materials shall be stacked according to the warehousing order, 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, 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, alloy steel pipe, etc., 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 goodIf there is only a single plane weld, that is, the arc of the section weld shall be terminated at the section arc.Granada,Performance index analysis fatigue of square tube the strength, plasticity and hardness discussed above are the indicators of the mechanical properties of metal under static load. In fact, many machine parts work under cyclic load, under which fatigue will occur.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.Montevideo,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, 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,GranadaCold galvanized steel pipe, light rail, large section steel, medium section steel, small section steel and square tube cold bending Section steel, high-quality section steel, wire rod, medium and thick steel plate sheet steel,GranadaGalvanized square pipe manufacturer, electrical silicon steel sheet, strip steel, seamless steel pipe, square pipe, welded steel pipe, metal products, etc.QB square tube is a product appeared in recent years, which mainly has strict tolerance and roughness for the dimensions of inner hole and outer wall. Production process classification of large-diameter qb square tube large-diameter qb square tube is divided into hot-rolled seamless square tube, cold drawn seamless square tube, seamless square tube and qb square tube according to production process. Among them qb square tube is divided into: (a) by process & mdash& mdash; Arc welded square pipe, resistance welded square pipe (high frequency and low frequency), gas welded square pipe and furnace welded square pipe (b) are divided by weld & mdash& mdash; Material classification of straight seam welded square pipe and spiral welded square pipe large diameter qb square pipe: plain carbon steel square pipe and low alloy square pipe. Ordinary carbon steel is divided into Q Q q SS, # steel, # steel, etc; Low alloy steels are divided into q Mn, St-, etc.Stage ( & mdash; )

The pipeline is only subject to chemical pickling, rust and old coating. Sometimes it can be used as the reprocessing after sand blasting. Although chemical cleaning can make the surface reach a certain cleanliness and roughness, its anchor lines are shallow and easy to pollute the surrounding environment. The square tube shall be submitted for acceptance in batches, and the batch rules shall comply with the provisions of corresponding product standards.The advantage of empty bending is that it can bend the side length when the real bending cannot be carried out, such as synchronous bending and finishing of the upper side and side of qb square tube. Empty bending can also bend the inner corner of r.t without fracture of pipe wall. The disadvantage of empty bending is that when the upper side and side are synchronous empty bending, due to the pressure generated by the upper roll and the lower roll at the same time, the forming force is easy to exceed the critical point, resulting in edge instability and concave, and will also affect the stable operation of the unit and forming quality. This is also the different characteristics of qb square tube and round tube empty bending.Principle of cold drawing strengthening: the lattice defects of steel increase during plastic deformation, and the serious distortion of defect lattice will hinder the progress and slip of lattice, so the yield point of steel increases and the plasticity and toughness decrease. Due to the internal stress in plastic deformation, the modulus of steel decreases. The cold drawn reinforcement is stored at room temperature for ~ d or heated to ~ ℃ and maintained for a fixed time. This process is called aging treatment.Click to view,It is the process of drawing the die hole of the rolled metal blank (shape, pipe, product, etc.) into a section to reduce the length and increase. It is mostly used for cold processing.The second is to clean the surface of the opposite pipe. When cleaning the opposite pipe, the surface should be cleaned with solvent or emulsion. Square pipes of various specifications, square rectangular pipes, seamless square pipes, galvanized square pipes, galvanized pipes are supplied in time and cost-effective. They have become the preferred brand of many wire products. Welcome to buy! It is used to remove oil and dust. It is only suitable for removing grease and dust on the surface of square pipe, which can not remove rust and oxide scale. Therefore, it can only be used as an auxiliary means in production.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 point

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.Discount,Solution treatment and nondestructive testing sand rolling treatment and sand blasting treatment many manufacturers in the market do not do solution treatment and % penetration nondestructive testing, and many of them use sand blasting instead of sand rolling. After these steps are omitted, the cost is greatly reduced.Avoid contact with pollutants such as oil and copper when storing square tubes.The pipeline is only subject to chemical pickling, which can remove oxide scale, rust and old coating. Sometimes it can be used as the reprocessing after sand blasting. Although chemical cleaning can make the surface reach a certain cleanliness and roughness, its anchor lines are shallow and easy to pollute the surrounding environment. The square tube shall be submitted for acceptance in batches, and the batch rules shall comply with the provisions of corresponding product standards.Granada,Stage ( & mdash; )Brinell hardness (HB), Rockwell hardness (HRC) and Vickers hardness (HV) are commonly used.The second is the pickling of the square pipe. Both chemical and electrolytic methods are used when pickling the square pipe. These two methods can remove the oxide skin of the square pipe.