Hebei Haihao Group

  • Which is better, 'cold rolling' or 'hot rolling'?

    Which is better, ‘cold rolling’ or ‘hot rolling’?

    Hot rolling and cold rolling are both steel plate or profile forming processes, and they have a great influence on the structure and properties of steel. The rolling of steel is mainly hot rolling, and cold rolling is only used to produce small section ste ...
  • Principles and characteristics of high frequency welding

    Principles and characteristics of high frequency welding

    High frequency welding principle: With the skin effect of the high-frequency current, the high-frequency electric energy can be concentrated on the surface layer of the weldment, and the proximity effect can be used to control the position and range of the ...
  • Difference between hot forming and cold forming

    Difference between hot forming and cold forming

    Both hot forming and cold forming form metal into its final shape,but what’s the difference between hot forming and cold forming.We compare them in several ways. Run Speed & Quality With hot steel, it might take 50 rolls to thin a workpiece out, ...
  • Introduction of hot forming process

    Introduction of hot forming process

    Hot forming process is used very frequently for casting of industrial products and parts. In this process, heat is applied to soften the piece of metal. This metal or raw material is available in the form of sheet, bar, tube or wire. Then some form of pres ...
  • Introduction of cold forming process

    Introduction of cold forming process

    Typically it’s a process in which the metal sheet or strip stock is placed between rollers and then compressed and squeezed. The amount of strain generated determines the hardness of the finished product. There can be numerous types of cold rolling m ...
  • The principle of strength lifting for stainless steel plate

    The principle of strength lifting for stainless steel plate

    The continuous strengthening of stainless steel sheet materials is constantly developing to meet the actual needs. There are many ways to strengthen the stainless steel plate. The strengthening of stainless steel plate can reduce the thickness of the plate ...
  • Treatment of corrosion resistance of stainless steel pipe surface

    Treatment of corrosion resistance of stainless steel pipe surface

    There are many ways of anticorrosive treatment on stainless steel pipes. By improving the surface treatment methods and processes of stainless steel pipes, many practical applications can be improved.(What is the main classification of stainless steel pipe ...
  • The development prospect of wear-resistant elbow industry

    The development prospect of wear-resistant elbow industry

    With the increase of engineering construction, the demand for new pipes is also growing. As a new type of pipe, wear-resistant elbow not only obtains competitive advantage, but also obtains more guarantee with high quality. Therefore, the application field ...
  • The benefits of ductile iron pipe

    The benefits of ductile iron pipe

    Ductile iron pipe, made from ductile cast iron, is a graphite-rich cast iron in which the graphite has a spheroidal shaped molecular structure. This molecular structure makes the cast iron less brittle and more resistant to impact than the other varieties, ...
  • Duplex/ Super duplex butt weld fittings (ASTM A815)

    Duplex/ Super duplex butt weld fittings (ASTM A815)

    The ASTM A815 specification covers duplex and super duplex butt weld fittings to match ASTM A790 and ASTM A928 pipes. These special grades of stainless steel are used for various chemical processes,  piping, oilfield piping and heat exchangers, flue gas de ...
  • The functions and methods of steel pipe coating

    The functions and methods of steel pipe coating

    Steel pipe coating is an anti-corrosion coating treatment, preventing steel pipes form corrosion or damage in the process of storage and transportation. In the past,steel pipes are all brushed artificially one by one by black bituminous paint. This work no ...
  • Difference between malleable cast iron pipe fittings and galvanized pipe fittings

    Difference between malleable cast iron pipe fittings and galvanized pipe fittings

    Malleable cast iron pipe fittings are made of malleable steel. It should be noted that although Ma steel is malleable cast iron with toughness, it cannot be used for forging. Ma steel pipe fittings and malleable cast iron pipe fittings are named by pipe ma ...
  • What is the main classification of stainless steel pipe?

    What is the main classification of stainless steel pipe?

    Stainless steel pipe belongs to a kind of steel pipe, it is made of the material of stainless steel so called stainless steel pipe. Its main material is 304, 304L, 316, 316L.Because of its corrosion resistance, beautiful appearance and other advantages, th ...
  • Steel pipe fittings material and production

    Steel pipe fittings material and production

    When we talk about the material of steel pipe fittings,we talk the material steel grade,for example,ASTM A234 WPB or A403 WP316L. It is the material information of this fitting,not the raw material steel grade for fittings production.A butt welding steel e ...
  • Prospects of pipe fittings industry

    Prospects of pipe fittings industry

    Hebei Haihao Group specialized in flange and pipe fittings. Elbow, flange, tee, cross, reducer, etc. all belong to pipe fittings, which widely used in building industry. Elbow is used at pipe turnings; flange is used to connect pipe at the end of pipe. Tee ...
  • Identification of seamless steel pipe

    Identification of seamless steel pipe

    A seamless steel pipe,a kind of long steel, has hollow section without seam. It is made from perforated tubular billets which are made of ingot steel or solid steel pipe and undergoes the process of hot rolling, cold rolling or cold drawn. Due to its hollo ...
  • The difference between ERW, DOM, and seamless steel pipe

    The difference between ERW, DOM, and seamless steel pipe

    ERW pipe (resistance welded pipe) The name ERW is because such stainless steel pipes involve certain types of welding processes such as spot welding and seam welding. Seam welding is usually used when manufacturing round, square and rectangular stainless s ...
  • What is the difference between pipeline series A and series B?

    What is the difference between pipeline series A and series B?

    Series A and series B are sometimes referred to as British or metric tubes, mainly because of their different outer diameters. The difference between series A and series B refers to the impact temperature in their properties. The impact temperature and the ...
  • Advantages and disadvantages of precision steel tube rolling at recrystallization temperature

    Advantages and disadvantages of precision steel tube rolling at recrystallization temperature

    Precision steel tube: hot rolling is relative to cold rolling, which is rolled below the recrystallization temperature, and hot rolling is rolled above the recrystallization temperature. Advantages of precision steel tube rolling at recrystallization tempe ...
  • Differences between carbon steel and stainless steel

    Differences between carbon steel and stainless steel

    Selecting the right type of steel for your project is one of the most important decisions. Before deciding individual material grades, it is also first necessary to decide which type of steel to use, such as carbon steel or stainless steel. This article wi ...