Four common derusting methods for spiral welded steel pipes

 1. Cleaning: use solvent and emulsion to clean the steel surface to remove oil, grease, dust, lubricant and similar organic matters, but it can not remove rust, oxide skin, welding flux, etc. on the steel surface, so it is only used as an auxiliary means in anti-government operations.

　　2. Acid cleaning: generally, chemical and electrolytic methods are used for acid cleaning. Only chemical acid cleaning is used for pipeline corrosion prevention, which can remove oxide scale, rust and old coating. Sometimes it can be used as the re-treatment after sand blasting and rust removal.

　　Although chemical cleaning of spiral welded steel pipe can make the surface reach a certain degree of cleanliness and roughness, its anchor pattern is shallow and it is easy to pollute the surrounding environment.

　　3. Tool derusting: mainly use tools such as wire brush to polish the steel surface to remove loose oxide scale, rust, welding slag, etc.

　　The derusting of hand tools can reach Sa2 level, and the derusting of power tools can reach Sa3 level. If the steel surface of spiral welded steel pipe is attached with solid oxide scale, the derusting effect of tools is not ideal, and the depth of anchor pattern required by anti-corrosion construction cannot be reached.

　　4. Spray derusting: spray derusting is to drive the spray blade to rotate at a high speed through a high-power motor, so that abrasive such as steel shot, steel sand, iron wire segment, minerals and other abrasives can spray the surface of the spiral welded steel pipe under the strong centrifugal force of the motor. It can not only completely remove oxides, rust and dirt, but also achieve the required uniform roughness of the spiral welded steel pipe under the strong impact and friction force of the abrasive.

　　After spray derusting, it can not only expand the physical adsorption of the pipe surface, but also enhance the mechanical adhesion between the anti-corrosion coating and the pipe surface. Therefore, spray derusting is an ideal derusting method for pipeline corrosion prevention.

　　Generally speaking, shot blasting is mainly used for inner surface treatment of pipes, and shot blasting is mainly used for outer surface treatment of spiral welded steel pipes.

　　During the production process, the relevant technical indicators of rust removal shall be strictly required to prevent the secondary damage to the spiral welded steel pipe caused by operation errors. After the removal of rust, the appearance of the spiral welded steel pipe will be smoother than that before the removal of rust. The removal of rust from the spiral welded steel pipe is a frequently used technology in the steel pipe industry.

The main factors affecting the internal hole finish of cold-drawn seamless steel pipe are as follows

     1. Pungent

　　The manufacturer's experience in piercing is not mature, the piercing temperature is not controllable, the piercing equipment is short, and the uneven heating of round steel causes large temperature difference inside and outside the steel pipe, forming pits, pits, peeling, etc., And the smoothness is not good. PMC has a slender perforating furnace, and the steel pipe is evenly heated.

　　2. Cold drawing die

　　There are defects in the cold drawing die itself, resulting in poor internal finish of the finished seamless pipe. PMC adopts professional customized precision molds with high precision and good internal and external surface quality of the finished products after cold drawing.

　　3. Pickling

　　Due to the strict environmental protection requirements in recent years, many manufacturers have no pickling process and can only be processed outside without professional experience. However, there is no data accumulation on the pickling time of steel, so the processing plant is allowed to process at will. The internal impurities of the cold-drawn seamless pipe cannot be thoroughly cleaned, or there are too many acids to form pits and pits. Since its establishment, PMC has a fully closed environmental protection pickling tank. After more than ten years of data accumulation, different steel grades have different pickling methods and times, which can ensure the internal hole finish.

What is the purpose of Q345C seamless steel pipe

 　Q345C seamless steel pipe is a kind of seamless steel pipe. Alloy pipe is divided into seamless pipe for structure and high-pressure heat-resistant alloy pipe.

　　It is mainly different from the production standard and industry of alloy tube. The mechanical function of Q345C alloy tube is modified by annealing and tempering. Meet the required processing conditions. Its function is higher than that of the ordinary seamless steel pipe. The chemical composition of the alloy pipe contains more Cr. It has the function of high temperature resistance, low temperature resistance and corrosion resistance.

　　The common carbon seamless pipe does not contain alloy components, and may have few alloy components. The reason why alloy pipes are widely used in petroleum, aerospace, chemical, power, boiler, military and other industries is that the mechanical functions of alloy pipes are changed and adjusted.

　　① No matter what steel pipe is carbon steel pipe, it is just that the carbon content of steel pipes of different specifications is different, and whether other trace elements are added to form steel pipes with special performance, such as stainless steel pipes

　　② Ordinary carbon steel pipes are very easy to rust in humid and corrosive environments, so surface treatment is usually required. The general treatment includes galvanizing, plastic plating, painting anti-corrosion paint, etc. Galvanizing is divided into hot galvanizing and cold galvanizing. The processing process is different. Hot galvanizing has better corrosion resistance and longer service life than cold galvanizing, but the price is high

　　③ Steel pipes are divided into welded steel pipes and seamless steel pipes according to different processing technologies. Generally, the steel pipes we use are welded steel pipes, and the seamless steel pipes are rarely used. Please refer to the design requirements, design documents, or consult the designer.

Stamping pipe fitting elbow technology

 Stamping pipe fitting elbow is mainly used to connect pipe fittings, which can play an important role in the development field of this product and set sail with technical level. The processing technology of stamping pipe fitting elbow has the following characteristics: in the production process, it is produced according to the following technology:

　　1. It is suitable for high-rise buildings with high water pressure.

　　2. The double clamping pipe fitting will not cut the rubber ring when it is inserted into the pipe.

　　3. When used in stainless steel pipe system, the dimension precision of double clamping pipe is improved, the error of pipe is allowed to increase, and the adaptability is strong.

　　4. The double compression type rubber ring is sealed in stainless steel material, the rubber ring is obviously improved, and the double compression type rubber ring is extruded evenly on the left and right, and the sealing ring will not be extruded from the side with double water pressure, which makes up for the deficiency in the application process of single compression.

　　5. At the double clamp joint, when the pipe is bent and deformed by external force, the sealing ring will not be affected. It is an upgraded product of stamping pipe fitting elbow type clamp connection technical performance, technical index and technical level.

　　Parameters of stamping pipe fitting elbow

　　The technological parameters of stamping pipe fitting elbow need to be used according to the production mode and method. The stamping pipe fitting elbow produced and processed has good use characteristics and advantages, and plays an important role and value in use. In the production of stamping pipe fitting elbow, we often encounter some different factors that affect the performance and process of stamping pipe fitting elbow. The process parameters that affect the geometry of stamping pipe fitting elbow are: the material, wall thickness and outer diameter of the blank for pushing, the material and shape of the mandrel head, the heating temperature and its distribution, and the pushing speed. Different factors have different effects on the performance of stamping pipe fitting elbow. In use, it needs to be used in accordance with the corresponding ways and methods. The specific use value and role of stamping pipe fitting elbow in use.

　　Stamping pipe fitting elbow is made of malleable cast iron, which is used to connect water supply pipeline, steam pipeline, gas pipeline and oil pipeline. The color of the stamping pipe fitting elbow is black, with right angle bending, good quality, easy to damage and not easy to damage. Stamping pipe fitting elbow specification for 1 / 2-10 inch, products are widely used in petroleum, chemical, metallurgical, electric power and other industries pipeline installation, installation, supporting services.

Characteristics of seamless carbon steel tee

 　Carbon steel tee is generally used for the installation of control valve, and it is used to drain. Concentric reducer is beneficial to fluid flow, and has less interference to fluid flow state when reducing diameter

　　Carbon steel tee is a steel tee formed by hot pressing or forging.Carbon steel tee generally has equal diameter tee, reducing tee and so on, the materials are carbon steel, alloy steel and stainless steel.

　　When the chromium content in the steel reaches about 1.2%, a thin oxide film (self passivation film) is formed on the surface of the steel due to the interaction between chromium and oxygen in the corrosive medium. The seamless carbon steel tee can prevent further corrosion of the steel substrate. In addition to chromium, the commonly used alloying elements are nickel, molybdenum, titanium, niobium, copper, nitrogen, etc, In order to meet the requirements of various uses on the structure and performance of concentric reducer, the production and processing technology of tee fittings are adopted to ensure that they can show good function and performance in production and processing

　　Carbon steel tee is a kind of steel which is resistant to weak corrosive medium such as air, steam and water and chemical corrosive medium such as acid, alkali and salt

Galvanizing process of flange

 　Advantages of hot dip galvanized flange:

　　1. Low cost: the cost of hot dip galvanizing is lower than that of other coatings;

　　2. Durable: in suburban environment, the standard thickness of hot-dip galvanizing antirust coating can be maintained for more than 50 years without repair; in urban or offshore areas, the standard thickness of hot-dip galvanizing antirust coating can be maintained for 20 years without repair; 3. Good reliability: the galvanized coating and steel are metallurgically bonded to form a part of the steel surface, so the durability of the coating is relatively reliable;

　　4. Strong toughness of the coating: the zinc coating forms a special metallurgical structure, which can withstand mechanical damage during transportation and use;

　　5. Comprehensive protection: every part of the plating parts can be coated with zinc, even in the depression, sharp corner and hidden place can be fully protected;

　　6. Time saving and labor saving: the galvanizing process is faster than other coating construction methods, and can avoid the time required for painting on site after installation.

　　Hebei Shengtian pipe fittings manufacturing Co., Ltd. will satisfy the customers according to the customers' demands. If there is any quality problem, we will return the goods unconditionally. The customers' satisfaction and praise is our constant pursuit.

　　Galvanized flange is to strengthen the corrosion resistance of carbon steel flange, a layer of zinc is plated on the surface of flange, so as to achieve the purpose of corrosion resistance.

　　The process of hot dip galvanizing of flange is pickling, assistant plating, drying, hot dip galvanizing, separation, cooling and passivation. Customers who buy flange will decide whether to galvanize according to the application requirements of flange. Hot dip galvanizing is an effective metal anti-corrosion method, which is mainly used in metal structure facilities of various industries. It is to immerse the steel parts after rust removal into the molten zinc at about 500 ℃ to make the surface of steel members adhere zinc layer, so as to achieve the purpose of anti-corrosion. The anticorrosion period of hot galvanizing is very long, but the anticorrosion period is different in different environments: 13 years in heavy industry zone, 50 years in ocean, 10 years in suburb.

How to select forged flange

 　　How to select the flange is mainly reflected in the selection of flange joint surface, because there are many flange joint methods, including welding flange, screw flange, etc. the sealing of welding flange is good, and it can withstand the fluctuation of high temperature and high pressure repeated bending. Large diameter flange links are the most common among them. Here I would like to share with you the ways and specific features of large diameter flange links:

　　First of all, large diameter flange links mainly include: large diameter flat welding flange and large diameter stainless steel flange. The wear of large flange has always been an important factor affecting safe and civilized production. With the continuous development of science and technology, materials are constantly innovated, Among them, alumina ceramic lining has become one of the most widely used wear-resistant materials because of its high wear resistance, high hardness, oxidation resistance, good corrosion resistance and high low temperature strength, Compared with carbon steel and manganese steel pipe, the wear resistance of the ceramic composite pipe formed by this method is improved to a certain extent. However, due to the low reaction temperature and short reaction time, the reduced alumina still stays in the low temperature phase β - Al2O3, and can not be converted into high temperature phase α - Al2O3

　　General flange large diameter connection, diameter of 7m, simple structure, convenient processing, and easy to carry out anti-corrosion. The other is the connection of threaded flange, which has better sealing effect than the former. It is determined that the structure is disordered and it is difficult to replace the gasket squeezed in the groove.

　　The determination of flange nominal pressure is related to the maximum operating pressure, operating temperature and flange data. Because the mechanical performance of 16MnR at 200 ℃ is taken as the benchmark when drawing up the flange size series and calculating the flange thickness. Therefore, the maximum allowable operating pressure of the flange size determined by the rule on this basis at 200 ℃ is considered to be the nominal pressure of the flange with this size.