SSAW Pipe

    Most of the seamless steel tubes produced now use hot rolling technology. Because of the high temperature, the deformation resistance is relatively small. Generally, the steel plate is used to complete the rectification rolling process. In this operation, it is also necessary to consider the The specific thickness, if the accuracy requirements are relatively low, the shape problem will not occur, mainly control-oriented, that is, in terms of temperature control, it is also a problem that must be considered at the same time, It can be said that the consideration of this part is also very important.     There are clear quality requirements for seamless pipes in the market, especially for different alloy elements. The harmful elements must be strictly controlled, and the danger of pipeline materials after production is also considered. And defects, such as cracks, internal folds, external folds, rolling, delamination, scarring, dents, etc., these must also be con...

    1) Tube appearance inspection     There are two kinds of raw material sources for casing tube blanks, one is seamless tube blank, and the other is ERW tube blank. The above blanks should be inspected as follows:     The whole pipe body is smooth and clean, and there are no obvious bumps, wrinkles, pits and other defects; if it is an ERW steel pipe, it should be checked whether the burr inside and outside the weld is scraped clean and the weld bead is smooth. Whether the nozzle has bumps, burrs on the inside and outside of the laminate, whether the flat chamfer is smooth and the chamfer meets the requirements; if it is an ERW pipe, it should be checked whether there is a weld crack in the nozzle.     Measure the inner and outer diameter dimensions, wall thickness and unevenness, cutting slope, ovality, and straightness of the steel pipe to determine whether the accuracy meets the requirements. Whether there is obvious dirt on the inner an...

    J55 oil jacket fusion zone defect:     After the ERW oil jacket, the welded pipe in the heat affected zone of the fusion line was found to be unqualified. Metallographic analysis, scanning electron microscopy and process research were carried out. The results show that the J55 welded pipe is on the fusion line. There is a certain depth of crack defect at the edge of the original plate in the heat affected zone. During the pipe making process, the user has a small pipe diameter and insufficient trimming amount, resulting in a significant increase in crack defects. The crack at the edge of the hot rolled original sheet originates from the corners of the cast slab and the subcutaneous bubbles.

    Analysis of cracking cause of hydraulic pressure test of P110 oil casing pipe : through analysis of chemical composition, fracture analysis and metallographic examination of the material, abnormal cracking of the pipe body after hydraulic pressure test of φ177.8 mm*11.51 mm P110 oil casing was performed analysis.     The results show that the reason for the longitudinal cracking of the pipe is that large inclusions are distributed in the casing body of the casing.The presence of the inclusions destroys the continuity of the material structure and weakens the transverse tensile strength. The stress exceeds the actual tensile strength to cause cracking.

    The biggest difference between ERW steel pipe and seamless steel tube is that ERW has a weld seam, which is the key to the quality of ERW steel pipe. Modern ERW steel pipe production technology and equipment, due to years of unremitting efforts in the world, especially the United States, have made the seamless ERW steel pipe has been relatively satisfactory.     Some people divide the seamlessness of ERW steel pipes into geometric seamlessness and physical seamlessness.     Geometric seamless is to remove the internal and external burrs of the ERW steel pipe. Due to the continuous improvement and improvement of the structure of the internal burr removal system and the cutter, the removal of internal burrs in steel pipes of large and medium diameters has been better treated. The internal burr can be controlled from -0.2mm to 0.5mm.     Physical seamless means that there is a difference between the metallographic structure inside the weld ...

    Today we will talk about the difference between 3pe anticorrosive steel pipe and epoxy coal asphalt anticorrosive steel pipe. 3pe anticorrosion and epoxy coal asphalt anticorrosion are two commonly used formsof steel pipe outer wall corrosion protection. The anticorrosion effect of 3pe anticorrosion steel pipe is better than epoxy coal asphalt anticorrosion steel pipe. Why do we say that?     1. Servicelife     3pe anticorrosive steel pipe can generally be used for about 30-50 years, epoxy coal asphalt anticorrosive steel pipe service life is between 20 years.     2. Processing technology     The three main raw materials of epoxy coal tar anticorrosion are composed of epoxy coal tar primer and top coat, and cold coal entangled tape of epoxy coal tar. Two oil, epoxy coal tar asphalt anti-corrosion steel pipe application I is the use of epoxy coal tar tar paint on steel pipes,generally in the form of painting, epoxy coal tar ta...

    1.The size of the casting cannot be too large: investment casting is mostsuitable for casting medium and small castings with a few shells to more thanten kilograms. In recent years, although the research and production oflarge-scale precision castings have made great progress, after all, there is alimit, and the size and weight can not be almost unlimited like sand casting.     2.The process is complicated: There are many investment casting procedures, theprocess is complicated, the production cycle is long, there are many factorsaffecting the quality of the bag ring castings, and the requirements for thematerial and process are relatively strict in production.     3.Slow cooling rate of the casting: The solidification and cooling rate of theinvestment casting is slow, and the crystal structure is coarse. Except forspecial products such as directional solidified columnar crystals and singlecrystal mussels, the mechanical properties of general alloy ...

    In the building materials industry, the development of various pipes is not thesame, because of their different characteristics, there is a certain distancebetween the pipes.     The various characteristics of small-caliber thick-walled steel pipes are known toeveryone, but because of the connection of raw materials such as small-caliberthick-walled steel pipes, the storage of small-caliber thick-walled steel pipesrequires specific conditions.     When storing small-caliber thick-walled steel pipes, we first need to choose asuitable place. We need to consider many external factors, the corrosivity ofsmall-caliber thick-walled steel pipes, etc., so the site must be cleaned.     In places where boring ventilation and harmful gases are present, small-caliberthick-walled steel pipes cannot be presented. Weeds and other debris should beremoved in time, and the outer surface of small-caliber thick-walled steelpipes should be kept clean. ...

    There are two types of steel pipes, one is seamless steel pipe, and the other is ordinary steel pipe, also called welded pipe. The seamless steel pipe has no joint gap on the body of the steel pipe, and the ordinary steel pipe is made by welding. Although the gap on the body of the steel pipe is invisible to the naked eye, it does exist. Among them, welded pipe is our most common steel.     Although its strength is not as good as that of seamless steel pipes, the currently used steel pipes generally do not use directly processed welded pipes. All of them have to undergo a certain treatment. After treatment, its performance will be improved. After forming a kind of steel pipe. Welded pipes can be said to be ubiquitous in our lives.     Welded pipes are used wherever they are not visible, so what are the advantages of welded pipes that make them used in various places?     1. The materials are simple. When producing seamless steel pipes, t...