Stage ( & mdash; )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, 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, enclosure,Van zerezDN25 hot dip galvanized pipe, 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, . ~ . 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, 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, 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 goodVan zerez,At the same time, the heating temperature and heating time will also have a great impact on the performance of square tube. The heating of square tube blank is the key process to ensure that the square tube blank has enough plasticity and complete the smooth perforation. If the heating temperature is too high or the heating time is too long, the billet of the square tube will be burned and decarburized,Van zerezWhere are galvanized square tubes sold, and even the chemical composition of the square tube will be unqualified (unqualified carbon content), which is easy to cause batch quality problems and seriously affect the product qualification rate.Alloy steel: A. low alloy steel (total alloy element content & le; %); b. Medium alloy steel (total alloy element content > ~ %); c. High alloy steel (total alloy element content > %).Qir Moav,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, 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, excessive stress concentration often shows microcracks in the bending process of profiles, 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.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.Fatigue strength, plasticity and hardness discussed above are indicators of the mechanical properties of metals under static load. In fact, many machine parts work under cyclic load, under which fatigue will occur.

Stage ( & mdash; )When cutting the square tube there will be deformation, uneven incision and crack of the incision. What should we pay attention to when cutting the square tube and how to operate it? Today, I will introduce some problems that should be paid attention to when cutting the square tube. If the correct operation will make the square tube cutting work very smooth, please use a rag or cloth to clean the oil on the surface of the square tube Sundries or soil shall be completely clean.Tool derusting mainly uses tools such as steel wire brush to polish the surface of square pipe, which can remove loose or oxidized scale rust, welding slag, etc. The derusting of manual tools can reach grade SA and that of power tools can reach grade SA. If the square pipe surface is firmly attached with iron oxide scale,Van zerezGalvanized square pipe 30, the derusting effect of tools is not ideal and can not reach the anchor depth required by construction.Credit guarantee,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, 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, and the center distance between them is adjusted to R + R + D.Alloy steel: A. low alloy steel (total alloy element content & le; %); b. Medium alloy steel (total alloy element content > ~ %); c. High alloy steel (total alloy element content > %).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.

During the pushing process of spot welding and repair welding elbows, there will be thinning, so manufacturers usually use thick spot pipes. If thin raw materials are used, the products produced must be unqualified. Generally, there are about wires thinned. If the technology is not good or the drawn pipe is used, the thickness is significantly lower than the standard.Marketing Department,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.In fact, the casting cleaning is not just shot blasting. For large parts, the drum sand cleaning is carried out first, that is, the riser of the casting is cut off and rolled in the drum, and the square tubes collide with each other in the drum to remove most of the sand on the surface before shot blasting or shot blasting.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.Van zerez,Stage ( & mdash; )Because the green billet can be pressed into any shape, it is easy to weld the square tube into difficult products.The load of impact toughness acting on the parts at a great speed is called impact load. It is specialized in products and renewable resources. Its business includes: square tube, seamless square tube, galvanized square tube and galvanized tube. The ability of metal under impact load is called impact toughness.