The disadvantage of empty bending is that during synchronous empty bending at the upper and side, 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. All kinds of square tubes, square rectangular tubes, seamless square tubes, galvanized square tubes and galvanized tubes have formal qualifications. Welcome to telephone inquiry and sincerely invite cooperation! It will cause 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.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, 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, etc. can be stacked in the open air; Small and medium-sized section steel, 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, 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, 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,JiusamoHot dip galvanized steel, 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,JiusamoHow much is a ton of galvanized square tube, . ~ . 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, 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 goodJiusamo,The raw material for rolling square tube is round tube blank. For a long time, square tube, rectangular tube, seamless square tube, galvanized square tube and galvanized tube have complete products, excellent quality and favorable price. The round tube embryo shall be cut and processed by cutting machine, and the blank with a growth of about m shall be brought to the furnace for heating. The billet is sent to the furnace for heating at a temperature of about degrees Celsius. The fuel is hydrogen or acetylene. The temperature in the furnace is the key problem. After the round tube billet is discharged from the furnace, it should be pierced through the pressure piercer. Generally, the more common piercer is the conical roll piercer. This piercer has high production efficiency, good product quality, large perforation expansion and can wear a variety of steel grades.The technology of floating mandrel and square tube is gradually mature.Puchov,If the re inspection results are unqualified (including the items whose preliminary inspection results are unqualified and re inspection is not allowed), the supplier can submit them for acceptance one by one; Or re conduct heat treatment (the number of RE heat treatment shall not exceed times), and propose acceptance with a new batch.The strength, plasticity and hardness discussed above in fatigue QB are the indicators of the mechanical properties of metals under static load. In fact, many machine parts work under cyclic load under which fatigue will occur.Square tube for automobile half shaft sleeve (gb-) is a high-quality carbon structural steel and alloy structural steel hot-rolled square tube for automobile half shaft sleeve and drive axle housing.

Functional index analysis of qb square tube - angular plasticity refers to the power of plastic deformation (permanent deformation) without destruction of qb square tube data under load.After the sample is flattened to the specified flattening distance h, remove the load and remove the sample.The square tube is divided into a. boiling steel according to the degree of deoxidation and pouring; b. Semi killed steel; c. Killed steel; d. Special killed steel. The deformation of qb square tube is mainly caused by the shrinkage force of the weld greater than the strength of the base metal.Latest consultation,Pull square tube:Hundreds of degrees Celsius, which can save energy.The characteristics of square pipe are as follows: the production process of square pipe is simple, the production efficiency is high, the cost is low and the development is fast. The strength of spiral square pipe is generally higher than that of straight seam square pipe. It can produce square pipe with larger pipe diameter with narrow blank, and square pipe with different pipe diameter with blank of the same width. However, compared with straight seam pipe of the same length, the weld length is increased by ~, which will be oriented to the whole country for a long time Individuals and enterprises provide all kinds of square tubes, square rectangular tubes, seamless square tubes, galvanized square tubes, galvanized tubes, on-site settlement honest operation, local offices, long-term cooperation, and low production speed. Therefore, most of the smaller square tubes adopt straight seam welding,JiusamoHow much is galvanized square tube 110, and most of the large-diameter square tubes adopt spiral welding.

Fake and shoddy square tubes are easy to scratch, because the equipment of fake and shoddy material manufacturers is simple and easy to produce burrs and scratch the surface of square tubes. Deep scratches reduce the strength of square tubes.Product line, ship steel boiler steel, pressure vessel steel, agricultural machinery steel, etc.After the process of polishing, the surface effect of the square tube is quite good. The quality of the polishing process directly affects the external image of the square tube. Therefore, we must choose the appropriate polishing according to the above, and pay more attention to the polishing process of the square tube.So flat, and the size and thickness are not standardized, it can reflect that this square tube is a poor product& rdquo;Jiusamo,Square tubes are classified by forming: forged steel; Cast steel; Hot rolled steel; Cold drawn steel.Square tubes for petroleum cracking (gb-) are furnace tubes, heat exchangers and pipeline square tubes suitable for petroleum refineries.The pressurization size and time are the key to the success or failure of welding. If the square tube synthetic material is not pressurized, a large number of pores will be caused due to the pores of the material itself and the gas generated in the reaction. It is not allowed to leave the reactants in the weld, so it must be densified, usually pressurized during the reaction.