• Corporate vision to become the pipeline industry Toyota
  • Corporate mission to enhance the quality level of Chinese manufacturing
  • Business goals domestic industry first
This week, we received an inquiry from a Myanmar customer about carbon steel elbow and large size carbon steel bend. The customer requires fittings shall have  carbon equivalent not exceeding 0.45%, Marking for pipe specifications ,heat number , bending angle, total lenght and heat shrinkable co ...

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With the development of the the Belt and Road policy, China has continuously cooperated with relevant countries and created more opportunities for domestic enterprises on the basis of helping other countries. Niger oil field surface phase II and Nigeria Benin pipeline project are integrated upst ...

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On August 24, one of HAIHAO’S business personnel received an inquiry from Saudi Arabia. He wanted to know about pipe fittings, flanges, elbows and other products. These components are used in an oil field. Because the project scale is relatively large, each product needs a variety of diffe ...

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What is the worst application environment for pipe fittings?We all know that the working environment of pipe fittings on land is relatively stable,while the environment on the seabed is more complicated than that on land.However there is another environment worse than that on the seabed,which is ...

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During the construction of a nuclear power plant,there are some basic requirements that need to be followed.We have gained a better understanding of these requirements through participating in Hainan Changjiang nuclear power phase II project.Let’s take a look at some of them. Pipeline prod ...

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In 1957,the world’s first commercial nuclear power plant,the shipping port nuclear power station in the United States,was officially put into use,and mankind officially entered the era of nuclear energy.In the development process of nearly 70 years since then,the development of nuclear power has ...

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Although the environment of steel market was not good in August,HAIHAO Group continued to provide good service and products to customers.On the 15th,we arranged shipments for customers in the Netherlands,Britain,Russia,Singapore and Saudi Arabia.Why HAI HAO can maintain its vitality in the adver ...

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The customer who asked for my inquiry because of the quality problems of the supplier before has confirmed the order this week. All details have been confirmed. The customer has sent me the Purchase Order, and WE are waiting for the customer to make payment and arrange production.  In March, a c ...

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As previously introduced, due to the supplier’s quality problems, the Brazilian customer purchased the order from our company for the first time. As the customer has strict requirements on delivery time, we have been producing for the customer as soon as possible under the premise of quali ...

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There is a customer who has quoted many prices before, but has never placed an order to our company.  The reason may be that the customer has a fixed supplier, and each quotation is to compare prices.  For me, although customers do not place orders for us, I always give customers quotations in o ...

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We received an inquiry from a UAE customer today.The inquiry content is about small size blind flange, and the customer requires galvanized flange surface. Today, let’s learn the types and differences of galvanized. Galvanized refers to the surface of metal, alloy or other materials coated ...

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Tensile test, generally refers to the tensile test, tensile test can determine a series of material strength indicators and plastic indicators. Strength usually refers to the ability of a material to resist elastic deformation, plastic deformation and fracture under the action of external forces ...

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Flattening Test– The flattening test as commonly made on specimens cut from tubular products is conducted by subjecting rings from the tube or pipe to a prescribed degree of flattening between parallel plates (As shown). Flattening test drawing The severity of the flattening test is measur ...

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Charpy impact test is used to measure the notch resistance sensitivity (toughness) of metal materials. The metal sample with a certain shape and size is prepared, so that it has a U-shaped notch or a V-shaped notch, in the charpy impact test machine in a simply supported beam state, with the pen ...

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After filling in the application form and submitting the information required for certification to the classification society, then the factory inspection, then the preparation of the type test. The type test is divided into hydrostatic test, low temperature impact test, flattening test, tensile ...

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To protect people and property, components and systems used in the maritime industry must meet high safety requirements. As the first recognized classification society in the maritime industry, DNV GL offers the guarantee of reliability and quality of products. So what is DNV GL certification? H ...

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API 5L generally refers to the executive standard of pipeline steel pipe, which is used to transport the oil, steam and water pumped out of the ground to oil and natural gas industrial enterprises. API 5L PSL1 Grade B seamless steel pipes Pipeline steel pipe includes seamless steel pipe and weld ...

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Attention should be paid to defects that may occur during pipeline steel pipe welding during production: 1.Bubble Bubbles mostly occur in the center of the weld, and hydrogen is still hidden in the form of bubbles inside the weld metal. The main reason is that the welding wire and flux have mois ...

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After heating, heat preservation and cooling, the performance of the metal will change differently, and the performance of the same flange pipe fittings will also be different after heating, such as the superior performance of stainless steel flange pipe fittings obtained by heating and cooling ...

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Heat treatment refers to a metal hot working process in which materials are heated, insulated and cooled in the solid state to obtain the expected microstructure and properties. Machine for heat treatment There are four basic processes for overall heat treatment of iron and steel: annealing, nor ...

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The heat treatment of pipe normally have five ways as below: 1.Quenching+high temperature tempering The steel pipe is heated to the quenching temperature, so that the internal structure of pipe can be transformed to austenite, then cooled faster than the cirtical quenching speed, so that the int ...

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After the metal is heated, insulated and cooled, the properties of the metal will change differently. After heating, the performance of the same flange pipe fitting will also be different. For example, stainless steel flanges have superior performance. The heating and cooling effects of pipe fit ...

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Hot dip galvanizing refers to melting zinc at high temperature and adding an appropriate amount of auxiliary materials to make a layer of zinc on the metal components. Cold galvanizing is a process of anti-corrosion treatment of workpiece surface based on electrochemical principle. Hot dip Galva ...

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The past several years we received many requirements about 3PE pipe. For this kind of pipe we are familiar with them because we have do many orders for our customers. 3PE pipe has three layer structure, the first layer of epoxy powder (FBE>100um), the second layer of adhesive (AD) 170 ~ 250um ...

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