Hardness 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 transportation: water supply drainage, sewage treatment engineering, mud transportation, marine water transportation.Tenellen,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 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.Robat Karim,Functional index analysis of qb square tube - commonly used are Brinell angle (HB), Rockwell angle (HRC) and Vickers angle (HV) of qb square tube. Angle is a gauge needle to weigh the soft and hard level of metal data. The angle method is rarely used to determine the internal angle in the current life. It uses the metal data surface tested under the fixed load of the indenter with a certain number and shape to determine its angle value according to the level of the object.With the improvement of production quality, their characteristics and uses are different. I will introduce the characteristics and uses of square tubes in detail.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.

When sand blasting or manual mechanical derusting is used, due to the falling off of the oxide scale of the galvanized square pipe, the metal on the surface of the galvanized square pipe is directly exposed in the air. If a primer is not applied in time, the surface of the galvanized square pipe is easy to rust again, affecting the adhesion of the paint film. I am engaged in all kinds of square tubes, square rectangular tubes seamless square tubes, galvanized square tubes, galvanized tubes and other materials all year round. I operate in good faith. Welcome to call! As the paint is a time-effective material, the overstock of inventory is easy to expire. Therefore, the main indexes of the paint must be rechecked before use, and the paint can be used only when the results meet the standards.In the test, ethylene, phenolic and other coatings commonly used for square pipes, the surface of square pipes is generally required to reach near white grade (SA). Practice has proved that almost all oxide scale, rust and other dirt can be removed by using this derusting grade, which fully meets the requirements of adhesion between layer and square pipe The shot derusting process can meet the technical conditions of near white level (SA) with low operation cost and stable and reliable quality.Discount,Square pipe welding is suitable for surface treatment of materials. Square pipe welding can be used for ceramic ceramic, metal ceramic and metal metal welding.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.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.

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.production,Empty bending empty bending is the bending moment formed in one direction between the outer roll and the outer wall of the tube blank to bend the strip. Empty bending will compress the bending line the compression effect will lengthen the bending line longitudinally, and the metal at the bending will accumulate and thicken, which is the compression thickening effect of empty bending.When cutting the sample, the surface of the sample shall not be damaged, the properties of the metal shall not be changed due to heating or cold processing, and the edges at the section shall be rounded.Product description of square tube square tube is a light thin-walled steel tube with hollow square section, also known as steel cold-formed profile. It is a section steel with square section shape and size, which is made of Q hot-rolled or cold-rolled strip or coil as the base material, cold bending and high-frequency welding. In addition to wall thickness thickening, weldability, cold and hot workability and corrosion resistance, and good low temperature toughness.Tenellen,Strength QB square 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,TenellenHot dip galvanized rectangular pipe, flexural strength and shear strength. There is often a certain between various strengths. Generally, tensile strength is used as the basic strength indicator. Precision pipe is a seamless pipe with high dimensional accuracy and good surface finish for mechanical structure and hydraulic equipment. The selection of precision seamless mechanical structure or hydraulic equipment can greatly save machining hours, improve material rate and improve product quality. Seamless pipe is rolled in the annular pass composed of variable cross-section circular hole groove and fixed conical plug. Cold drawing is usually carried out on single chain or double chain cold drawing machine. This method is to put the heated pipe blank in a closed cylinder and the perforated rod and rod move to extrude the part from the smaller die hole. This method can produce steel pipe with smaller diameter.Due to the increase of square tube production, there are more and more fake and shoddy square tubes in the market. How to distinguish the fake and shoddy square tubes? Let me teach you some points to distinguish the fake and shoddy square tubes., etc. Hot rolled seamless tubes are produced on the automatic precision tube precision tube rolling mill. The solid tube blank is cut into the required length by removing surface defects tubes, centering on the end face of the perforated end of the tube blank, and then sent to the heating furnace for heating. It is perforated on the piercing machine. At the same time, it rotates and advances continuously under the action of roll and plug, A cavity is gradually formed inside the pipe blank,TenellenWelded galvanized pipe, which is called the rough pipe, and then sent to the automatic pipe mill for continuous rolling. After the wall thickness is adjusted by the whole machine, and the diameter is determined by the sizing machine to meet the specification requirements. The continuous pipe mill is more advanced in producing hot-rolled seamless steel pipe. If you want to obtain seamless pipe with smaller size and better quality, Cold rolling and cold drawing must be adopted, that is, the heated pipe blank is placed in a closed cylinder, and the perforated rod and rod move, This method can produce steel pipe with small diameter. In the building materials industry, the development of various pipes is different. Because of their different characteristics, there is a certain distance between pipes. Square pipe is one of many pipes in the building materials industry. It is formed after strip steel treatment. We need to understand the various characteristics of steel pipes. However, in the building materials industry, the development of various pipes is different. Because of their different characteristics, there is a certain distance between pipes. Square pipe is one of many pipes in the building materials industry. It is formed after strip steel treatment. The various characteristics of steel pipe need to be understood by everyone. However, due to the of steel pipe and other raw materials, the storage of steel pipe needs specific conditions.