Shanghai ShengQiu Materials Co., Ltd

  Generally speaking, the production process of thick-walled seamless pipe can be divided into two types: cold drawn/rolled and hot rolled. The production process of cold rolled seamless steel pipes is generally more complicated than hot rolled. First, the billet will be subjected to three-rolled continuous rolling, and then the sizing test will be carried out after extrusion. If the surface does not respond to cracks, the round pipes will be cut into one meter long. The next step is annealing process. Annealing needs to be pickled with acidic liquid. When pickling, pay more attention to whether there are a lot of bubbles on the surface. If there are a lot of bubbles, it means the quality of the steel pipe does not meet the standard. In appearance, cold rolled seamless steel pipes are shorter than hot rolled seamless steel pipes. The wall thickness of cold-rolled seamless steel pipes is generally smaller than hot-rolled seamless steel pipes, but the surface looks brighter than thic...

  The method of using acid solution to remove oxide scale and rust on the surface of steel is called pickling. Acids for pickling include sulfuric acid, hydrochloric acid, phosphoric acid, nitric acid and mixed acids. The pickling process is to remove the surface oxide scale, and then go through lubrication treatment (carbon steel-phosphorous saponification, stainless steel-butter lime, copper and aluminum pipe-oiling, using the old process-copper plating), and then deep drawing processing. If the steel pipe is not pickled, there may be oxides and oil stains on the surface, and probably the phosphating solution cannot be able to remove them and the quality of phosphating will be reduced. In addition, in the manufacturing process of steel pipes, after many processes, if you are not careful, scars will appear on the surface of the steel pipes, which will reduce the corrosion resistance of the parts and affect the service life. In order to improve the corrosion resistance of the steel...

  Thick Wall Steel Pipe And Its Application   The steel pipe with outer diameter to wall thickness ratio is less than 20 is called thick-walled steel pipe. Mainly used as petroleum geological drilling pipes, cracking pipes for petrochemical industry, boiler pipes, bearing pipes and high-precision structural pipes for automobiles, tractors, and aviation.   The biggest difference between thick wall steel pipe and thin wall steel pipe is the wall thickness. Generally speaking, thin wall steel pipes are cold drawn/rolled and thick-walled steel pipes are hot-rolled. If it is distinguished by measurement units, it is generally believed that thickness/ diameter equal to 0.02 is the demarcation point between thick wall steel pipes and thin wall steel pipes, thin wall steel pipes are less than 0.02 and thick wall steel pipes are more than 0.02. In terms of usage, thin-walled steel pipes are mostly used for pipelines and thick wall steel pipes are mostly used in blanks of h...