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The development trend of J55 oil casing coupling

The development trend of J55 oil casing coupling J55 oil casing coupling has become a special anti-corrosion for petroleum gas pipelines. More and more J55 oil casing coupling manufacturers have sprung up like bamboo shoots after a rain. They have seen the bright prospects of this industry, but they have seen the demanding quality requirements of this industry. If…

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What are the common defects of line pipe welding

1. Air bubbles. Air bubbles mostly occur in the center of the weld bead. Hydrogen is still hidden in the weld metal in the form of bubbles. The main reason is that the welding wire and flux have moisture on the surface, so they can be used directly without drying, and welding In the process, the current is small,…

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The specific production method of L245 line pipe

A production method of L245 line pipe This patent relates to a production method of line pipe, especially a production method of L245 line pipe. For the production of large-diameter, thick-walled, and extra-thick-walled seamless L245 line pipes, the traditional methods are the pipe jacking-extrusion method and the Pilger method. The obvious shortcomings of the above two production methods are:…

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Analysis of cold treatment cracks of seamless steel pipes

For seamless steel pipe high-carbon alloy steel, some subcooled austenite has not been transformed into martensite after quenching, and it remains in use as retained austenite, which affects its performance. If it is placed below zero to continue cooling, it can promote the martensite transformation of retained austenite. Therefore, the essence of cold treatment is to continue quenching. The…

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What is the difference between seamless steel pipe and carbon steel pipe

1. Seamless steel pipes are steel pipes without welds manufactured by piercing and hot rolling. Sometimes it is necessary to further cold work the hot processed pipe in order to obtain the corresponding shape and size. Carbon steel pipes are generally made into round, square, and flat shapes through multiple rolling. 2. Seamless steel pipes are the most used…

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