steel tube

　　Wrong Side of High Frequency Straight Seam Welded Pipe : 　　Wrong side of high frequency straight seam welded pipe is the most common pre-welding problems, ultra-poor of the wrong side will directly lead to the degradation of steel or scrap. Therefore, pre-welding requires strict control of the amount of wrong side. When the whole root or half of the steel pipe billet error occurs when the general is due to: 　　1, Open seam adjustment is not in place (seam side); 　　2, The joint pressure roller adjustment is not in place (pressure roller circumferential angle is not right, or to the tube centerline as the axis, the left and right pressure roller asymmetry, or the relative pressure roller radial extension is inconsistent), no pressure round; 　　3, The pre-bend is not pre-bending in place, there is a straight edge edge of the phenomenon. 　　When the head or tail of the tube is wrong, it is generally due to: 　　1, The import and export roller position is not right; 　　2, Ring fra...

　　Pre-welding quality of straight seam steel pipe includes seam quality and weld quality. 　　(1) Joint (that is, forming seam) no wrong side or wrong side is less than the specified value, the general provisions of the wrong amount ≤ 8% thickness, the maximum does not exceed 1.5mm. 　　(2) To ensure that the weld has a suitable penetration depth and welding volume, it is necessary to ensure that after welding does not crack, does not produce burning phenomenon, but also to control the weld height, the weld weld height does not have an impact. 　　(3) The weld is continuous, good shape, in order to help ensure the final external welding quality. 　　(4) Weld does not exist welding bias, pores, cracks, slag, burning and back welding and other defects, requiring weld center deviation ≤ 1 mm. 　　(5) No arc burns, splash small, does not affect the tube end groove and surface quality. 　　(6) Weld and base metal match, weld metal physical and chemical properties to meet the quality requir...

　　 Straight seam steel pipe fracture, hydraulic (pneumatic) parts in the design of the use of mechanical properties, brittle fracture is also related to the use of components temperature. 　　It has been found that when the temperature is below a certain temperature, it is found that the information will be transformed into a brittle state, and its impact absorption is significantly reduced. This phenomenon is called low stress brittle fracture in cold brittle and high strength metallic materials. In the process, the data organization is far from uniform, isotropic, there will be cracks, there will be inclusions, pores and other defects, these defects can be seen as micro-cracks in the material. Therefore, the design should also be based on the work of the component temperature to select the appropriate cold brittle transition temperature of the information. 　　In general, it is assumed that the information is uniform and continuous isotropic, according to this method analysis is con...

　　Effects of Deoxidizer on High Frequency Straight Seam Welded Pipe : 　　1.For the ω (Als ≤ 0.01% straight seam welded pipe, the use of two deoxidizer on the VD treatment of steel in the total oxygen impact is small, can be ω (T.O control in the 20 × 10-6 below; Si-Al-Ba deoxidation After the process can be a lower total oxygen content, the process of deoxidation effect is stronger than Si-Ca deoxidation effect. 　　2.When the Si-Ca and Si-Al-Ba two kinds of deoxidizer are used in the high-frequency straight seam welded pipe, the number and size of the inclusions in the smelting process are quite different. The number of inclusions in Si-Al-Ba Less than Si-Ca after deoxidation, and smaller size. 　　3.The inclusions in the forging material differ greatly from those in the aluminum inclusions. When the Si-Al-Ba deoxidation is used, the inclusions in the forging material are dominated by massive and chain alumina, and the high-frequency straight seam welded pipe uses Si-Ca deoxidation T...

　　The seamless steel pipe for fluid transportation is a general seamless steel pipe for conveying fluids such as water, oil, gas, etc., and a steel pipe having a hollow section and having no weld seam from beginning to end. The use of steel pipes to manufacture ring-shaped parts can improve the material utilization rate, simplify the manufacturing process, save materials and processing man-hours, such as rolling bearing rings, jack sleeves, etc., and have been widely used in steel pipes. Steel pipes are also indispensable materials for various conventional weapons, and barrels, barrels, etc. are all made of steel pipes. Steel pipes can be divided into round pipes and shaped pipes according to the shape of the cross-sectional area. Since the area of the circle is the largest under the condition of equal circumference, more fluid can be transported by the circular tube. In addition, when the circular section is subjected to internal or external radial pressure, the force is relatively un...

　　Several days ago, we introduced the types of tube that used in oil pipeline , today, we will share the connection modes of oil pipelines for people those interested in this aspect. 　　Oil pipeline must use a certain connection to form a complete system. Connection methods of pipeline are mainly three categories, including screw thread, welding and flange connection. 　　When the pressure is not high, the pipe with small diameter can be connected by using screw thread this method. This connection method is very convenient, but most of the diameter of oil pipelines are generally larger, so other two connection methods are used commonly. 　　The pipeline that DN≥50 basically uses welding method to connect. Welding has many advantages, such as convenient construction, strong, tight and saving steels. The general straight pipe or bends those parts do not need to tear down can use this method. 　　The connection of pipes and valves or other equipment (such as: pump) and the parts those ne...

　　Welded carbon steel pipe includes LSAW (longitudinal submerged arc welded) steel pipe and spiral welded pipe . Some people those do not very understand this industry may not know differences between the former and the latter very clearly. Don’t worry, today we will talk about this topic. 　　Spiral welded pipe is made by using low carbon construction steel strip or low alloy structural steel strip to roll into a tube according to a certain helix angle (called the forming angle), and then welding the seam together. It can use the narrow band steel to produce steel pipe with large diameter. Spiral welded pipe is mainly used for oil and natural gas pipeline, its specifications are expressed by outer diameter * wall thickness. Spiral welded pipe with also includes single-sided welding and double-sided welding. 　　LSAW steel pipe is made by using strip steel as raw materials and doing longitudinal welded in the high-frequency welding equipment(hence the name due to the weld forms a strai...