LSAW Steel Pipe

 　　In December of 2020, Xinyue received an inquiry for the bidding of seamless pipe project from Algeria, Africa. This was a newly developed customer. In order to had better understanding about the project situation,our sales engineer conducted detailed negotiation and communication with client. Combined with the specific needs of the project, we customized a service plan and a reasonable quotation for the customer, and cooperated with the customer to prepare the technical documents and technical reports required by the bidding. The meticulous and thoughtful service of whole process left a deep impression on the customer. Finally, in April 2021, the customer successfully won the project order and shared the good news with Xinyue at first time. 　　The pipes used in this batch of projects were more than 500 tons of seamless pipes with the same outer diameter and wall thickness, but the length requirements were different, and the pipe ends need to be connected with male and female thre...

 　　Last week, the domestic scrap price was consolidated and operated, the market resources were still tight, the business operation enthusiasm was not high, and the arrival of steel mills was different. Most of them adjusted the purchase price according to their own situation. 　　Compared with the previous week, the average purchase price of scrap in key steel enterprises was reduced by 16 yuan / ton, 12 yuan / ton and 9 yuan / ton respectively. 　　Last week, although the prices of finished products and billets rose, they were limited to boost the scrap market. In order to ensure the year-on-year decline of crude steel output in 2021, steel mills in Shandong, Jiangsu and other places took the initiative to reduce production, blast furnace shutdown and maintenance increased, scrap demand weakened, more on-demand procurement, and individual steel mills with large impact reduced procurement prices. Considering the current reduction in the circulation of scrap resources, the arrival of s...

 　　Driven by the production restriction policy, the steel market performed eye-catching in July. As of July 31, the hot coil futures price had exceeded the 6100 yuan / ton mark, the rebar futures price was close to 5800 yuan / ton, and the coke futures price was close to 3000 yuan / ton. Driven by the futures market, the spot market generally rose. Taking billet as an example, the price of mainstream billet reached 5270 yuan / ton, with an increase of nearly 300 yuan / ton in July. Overall, the rise has become the main tone of the recent steel market. However, with the adjustment of steel export tariff policy again, this upward trend may usher in a watershed. 　　On July 29, the Tariff Commission of the State Council announced that from August 1, the export tariffs of ferrochromium and high-purity pig iron will be appropriately increased, the export tax rates of 40% and 20% will be implemented respectively after adjustment, and the export tax rebates of 23 kinds of steel products suc...

 　　Reviewing the operation trend of China's iron and steel industry in the first half of this year, it is mainly manifested in the following characteristics: 　　First, steel prices increased significantly year-on-year. In 2021, steel prices continued to rise after the Spring Festival, fell rapidly after hitting a record high in mid May, rebounded slightly in June and entered the shock adjustment market. The year-on-year increase in the price of steel varieties is mostly 30% ~ 50%. The prices of raw fuels such as iron ore and coal coke rose sharply year-on-year and month on month. 　　Second, there is strong demand in downstream industries. With the simultaneous development of domestic and foreign demand, China made a good start in the first quarter and all economic indicators improved. Driven by loose monetary policy and domestic and foreign demand, domestic steel demand has increased rapidly. This can be seen from the inventory. After the Spring Festival, the peak of total steel inve...

 　　Since the establishment of the company, Xinyue has adhered to its original intention, always put customers first, adhered to the "altruistic principle" and always recognized the "symbiotic value", which is the long-term way for the development of the enterprise. Xinyue believes that no matter how advanced the times are, customers are the foundation of the enterprise's development road. With the correct development decisions of the company's leaders, Xinyue has stood in the iron and steel industry for decades, has a good reputation in the industry, and has been recognized and supported by the majority of customers; The power of word-of-mouth in the industry often brings a chain reaction, not only improves the corporate image, but also some regular customers and old friends take the initiative to introduce new customers to us. At the same time, some new customers come to seek cooperation and development with Xinyue. 　　Recently, we met a new customer who cam...

 　　The heat treatment process of seamless steel pipe mainly includes the following 5 categories: 　　1. Quenching + high temperature tempering 　　The steel pipe is heated to the quenching temperature to transform the internal structure of the steel pipe into austenite, and then rapidly cooled at a speed greater than the critical quenching speed to transform the internal structure of the steel pipe into martensite, and then with high temperature tempering, the steel pipe structure is finally transformed into a uniform Tempered sorbite structure. This process can not only improve the strength and hardness of the steel pipe, but also organically combine the strength, plasticity and toughness of the steel pipe. 　　2. Normalizing 　　After heating the steel pipe to normalizing temperature, the internal structure of the steel pipe is completely transformed into austenite structure, and then it is a heat treatment process that uses air as a medium for cooling. Different metal structures can be ...

 　　What is precision hydraulic seamless steel pipe? ——Refers to cold-drawn or cold-rolled precision seamless steel pipes with precise inner diameters for the manufacture of hydraulic and pneumatic cylinders. 　　Introduction of precision hydraulic seamless steel pipe process: 　　Precision hydraulic seamless steel pipes made of precision cold drawn seamless steel pipes that are processed by black or gray phosphating process, and the phosphated steel pipes are sealed and rust-proofed. 　　A dense phosphate layer is formed on the inner and outer surfaces of the steel pipe. After the anti-rust treatment, the steel pipe is effectively prevented from being oxidized. Therefore, the steel pipe has excellent anti-rust performance. At the same time, the microporous phosphate film (layer) formed after the steel pipe surface It can effectively absorb the paint on the surface of the steel pipe and effectively prevent the paint from falling off. It is an ideal product for use in a field operation env...

 　　How to Solve these Problems Encountered in Welding? 　　1. Cracks 　　Hot cracking, in the process of welding seam cooling, due to the sulfur and phosphorus impurities in the steel or welding material and the steel to form a variety of brittle and hard low-melting eutectics, in the process of welding seam cooling, solidified low-melting eutectic Under tension, it is easy to crack. 　　Cold cracks, which occur in the range of 200℃ to room temperature, have delayed characteristics. They appear in a few minutes to a few days after welding, so they are also called delayed cracks. It is related to the selection of steel, the design of the structure, the storage and application of welding materials, and the welding. The craftsmanship is closely related. 　　Preventive measures: For cold cracks, welding rods with good crack resistance, low hydrogen or ultra-low hydrogen, and low strength should be selected, and the preheating temperature and heat input energy should be controlled to reduce the...

 　　Causes of scratches on the surface of welded pipes (LSAW/SSAW/ERW Pipe): 　　The welded pipe using roll forming requires the strip to be bent into a circle transversely. This is achieved by deforming the strip by a series of rolls with different grooves. Each pair of rolls rotates at a certain speed, but the linear velocity of the roll surface is different due to the radius of rotation. However, the difference in linear speed makes the sliding friction between the strip and the forming roller the root cause of the scratches on the surface of the welded pipe. 　　Most welded pipe mills adopt the horizontal forming method. For this mill, the active roll bottom diameter of the roughing roll, guide ring roll and sizing roll is considered to be the driving diameter, and the linear velocity of these roll bottom diameters is basically equal to the conveying speed of the strip. Due to the different radius of rotation, the roll edge of each roll makes the relative sliding friction between th...

 　　Submerged arc welding (SAW) is mainly suitable for welding at the flat welding position. If certain tooling aids are used, welding at fillet welding and horizontal welding positions can be realized. The main factor that affects the shape and performance of the submerged arc welding seam is the welding process parameters. 　　The welding parameters of submerged arc welding mainly include: welding current, arc voltage, welding speed, welding wire diameter and extension length. 　　1. Welding current 　　Under general welding conditions, the weld penetration is directly proportional to the welding current. 　　With the increase of welding current, the penetration depth and weld reinforcement increase significantly, while the width of the weld does not change much. At the same time, the melting amount of the welding wire also increases correspondingly, which increases the residual height of the weld. As the welding current decreases, the penetration and the surplus height decrease. 　　2. Arc...