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, 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, and generally adopts ordinary closed warehouse, 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, 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,Gdansk40 square pipe galvanized, 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, 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, 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 goodNormalized: A. pearlite steel; b. Bainitic steel; c. Martensitic steel; d. Austenitic steel.Gdansk,Functional index analysis of square tube - angular plasticity refers to the power of plastic deformation (permanent deformation) without destruction of square tube data under load.Steel for construction and engineering according to the classification of use without phase transformation or partial phase transformation of square tube: A. ordinary carbon structural steel; b. Low alloy structural steel; c. Steel reinforcement.Studenichani,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.Cold drawn or cold rolled precision square tube (gb-) is a cold drawn or cold rolled precision square tube with high dimensional accuracy and good surface finish for mechanical structure and hydraulic equipment. The selection of precision square mechanical structure or hydraulic equipment can greatly save machining hours, improve material rate and improve product quality.It should be noted that the position of the disc from the calibration line can be adjusted according to the reinforcement diameter,Gdansk16 galvanized square pipe, and R and R can be equal or different.
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, 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.Therefore, QA is usually not preheated. However, when the plate is very thick, it should be preheated because it cools quickly. Once # steel was cracked by J welding. If the plate thickness is more than mm, there is a great risk of not preheating.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.Good quality,The surface of fake and inferior square tubes is easy to produce scabs. There are two reasons: the material of fake and inferior square tubes is uneven and there are many impurities. The guide equipment of fake and shoddy material manufacturers is simple and easy to stick to steel. These impurities are easy to scar after biting the roll.Square tube is made of different materials. It needs qualified inspection by relevant staff before leaving the factory. Square tube has a wide range of uses. Its main field is not only the construction industry, but also can be seen everywhere in our daily life. The service life of square tubes is mainly affected by surface treatment. I will explain the specific operations of surface treatment of square tubes.Square tube, modified square tube, square tube, QB square tube and hot-rolled square tube are qualified in quality inspection. The manufacturer adopts advanced equipment to ensure the quality of each product. Magnetic flux leakage testing for surface defects of square tubes is very similar to magnetic particle testing for square tubes, and its scope of application, sensitivity and reliability are stronger than magnetic particle testing. Indirect square forming process the traditional forming process of cold-formed square pipe is to gradually roll the hot-rolled steel coil multi stand forming unit into round pipe at room temperature, and then the shaping unit will roll the round pipe into square pipe, which is called indirect square forming process. The traditional roll forming process uses the method of fixed bending point position and variable bending radian to complete the corner forming of pipe blank, which is suitable for rolling small and medium-sized products. Rolling with this process & ldquo; Superb & rdquo; Square tube will show its inherent defects. Because the roll work in the bending process of this process is always concentrated at the point, which will lead to cracking in serious cases. The products with such defects have serious consequences when they are used in building steel structures. The study of the broken square tube column in the Hanshin earthquake in Japan shows that the corner microcrack is the main cause of the square tube fracture. At the same time, due to the different forming bending radians of products with different wall thickness, the universality of rolls is limited. The large-size cold-formed square tube used in the process adopts the advanced & ldquo; Direct Square & rdquo; The production process is to directly roll the hot-rolled steel coil into a square and rectangular shape at room temperature.
Square tubes for petroleum cracking (gb-) are furnace tubes, heat exchangers and pipeline square tubes suitable for petroleum refineries.Latest quotation,After cold drawing and aging treatment, the yield point is improved, the tensile ultimate strength is also increased, and the plasticity continues to decrease. Due to the reduction of internal stress during aging the modulus can be basically restored. According to this principle, cold drawing or cold drawing of reinforcement or low carbon steel wire rod is often carried out on site or prefabricated component factory, so as to improve yield strength and save steel.In the process of processing,GdanskGalvanized seamless pipe, the processing temperature is the key. Professional square tube, square tube, seamless square tube, galvanized square tube and galvanized tube have advanced technology, strict detection, more affordable price and more preferential price. Consultation is welcome. It must be noted that the blank heating should be uniform. Perforation has a great impact on the quality. The perforation temperature of blank varies according to different materials, generally around ℃.When storing QB square pipe, we need to select a suitable place. We need to think about many external factors, such as the corrosivity of steel pipe, etc. Therefore, the place must be clean, dry and ventilated, where harmful gases appear QB square pipe can not appear, weeds and other sundries should be removed in time, and the outer surface of steel should be kept clean. If there are acid, alkali, salt, etc. in the warehouse, it is easy to react with the steel pipe and corrode the steel pipe, so try to cut it and don't let it. In addition, if we can think about those higher metal products, we can put them into the warehouse for very good retention. According to geographical conditions, there is a sealed warehouse, but the ventilation setting is excellent. The difference between QB square tube and seamless steel tube QB square tube is a kind of high-precision steel tube material after cold drawing or hot rolling treatment. QB square tube is mainly used to produce products of pneumatic or hydraulic components, such as air cylinder or oil cylinder, which can be seamless pipe or welded pipe, because there is no oxide layer on the inner and outer walls of QB square tube, no deformation under high pressure, high precision, high finish, cold bending, flaring and flattening without cracks. The chemical composition of QB square tube includes carbon silicon Si, manganese Mn, sulfur s, phosphorus P and chromium CR.Gdansk,Generally, chemical and electrolytic methods are usedAfter chemical pickling, the square tube can be well protected by electrolysis. These are simple ways to prolong the service life of the square tube, We only need to treat according to these, so that the square tube can bring us great help in the use process. The cold galvanized square tube is the principle of cold galvanizing on the square tube used to make the square tube have corrosion performance. Different from hot-dip galvanizing, cold galvanizing coating is mainly carried out according to the electrochemical principle. Therefore, it is necessary to ensure the sufficient of zinc powder and steel, resulting in electrode potential difference, so the steel surface treatment requirements are very high.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; Straight seam welded square pipe, spiral welding