steel tube

    Large diameter straight seam steel pipe welding, including pre-welding, welding and welding outside the three processes. The so-called pre-welding that is, after the steel pipe forming, the use of continuous high-speed gas shielded welding (MAG) method of forming steel pipe positioning welding. After the pre-welding, respectively, within the steel pipe, multi-wire submerged arc welding. In the case of high-speed gas-shielded pre-welding, there are currently two methods. One is the use of single-wire dual-power high-current high-speed gas protection pre-welding, such as the United States, Germany that is used in this way; the other is double-wire high-speed gas protection pre-welding, Japan is the use of this method. At present, more applications are monofilament high-speed gas protection pre-welding method, in a reasonable welding process conditions, can achieve not less than 7m / min high speed, and straight bead forming beautiful. As the pre-welding of the first step of ...

    There are many factors that affect the quality of large diameter double-sided submerged arc welding steel pipe(dsaw steel pipe). The key factors that directly relate to the quality of diameter forming are the expansion ratio, the amount of axial overlap, the number of segments and the rounded corners, The friction and lubrication between the block and the inner wall of the steel pipe, the shape error of the steel pipe, the expanding speed and the straightening setting of the expanding machine.     (1) When the enlarging rate is small, the roundness error of the steel pipe decreases with the enlarging rate, but when the enlarging rate increases to a certain value, with the enlargement rate increasing, The roundness error of the steel pipe will increase greatly. In the actual production, the expansion ratio is controlled between 0.8% and 1.5%.     (2) The amount of axial overlap has a certain influence on the uniformity of the longitudinal deformation...

    Thick-walled steel pipe, the pipe diameter and wall thickness ratio of less than 20 like that steel pipe known as thick-walled steel pipe. Mainly used for petroleum geological drilling tube, petrochemical cracking tubes, boiler tubes, bearing tubes and automotive, tractors, aviation and other high-precision structural control.     The biggest difference between the thick wall steel pipe and thin-walled steel pipe is the wall thickness, in general, are thin-walled steel pipe belongs to drawing technology, and thick-walled steel generally use hot-rolled technology, if it is measured wall thickness / pipe diameter is equal to 0.05 that is a thick-walled steel pipe and thin-walled pipe watershed, wall thickness / diameter less than 0.05 that is a thin-walled steel pipe, thicker than the steel pipe, in use On, the thin-walled steel pipe used for pipe. The thick-walled steel pipe and more hollow parts used in the blank. Pressure and the use of important pipelines. ...

    Seamless pipeline is mainly used for conveying high-pressure oil and gas near the wellhead. With the increasingly serious problem of hydrogen sulfide corrosion, the development of anti-sulfur seamless pipeline is imminent, and the performance of sulfur-resistant is the key. The influence of Cu and Ni on the HIC properties of the carbon seamless steel pipe materials and the S content in the steel were also investigated. The effects of Cu and Ni addition on the properties of the HIC were also investigated. Hydrogen bubbling sensitivity.     With the deepening of oil and gas exploration, mining conditions are complex and the oil and gas wells in the sulfur environment more and more, hydrogen sulfide corrosion is very acute. In recent years, domestic and international demand for sulfur-resistant seamless pipe line is increasing. Seamless pipeline is mainly used for conveying high-pressure oil and gas near the wellhead, is the use of seamless pipe production method...

    1, The supply of astm a53 seamless steel pipe compared to other traditional pipe, raw materials lighter, high strength, good tolerance, can withstand high internal pressure, the production of sensitive, and can be used to messy or harsh geological conditions.     2, But the steel pipe in the course of the existence of a large rate of end, the main internal and external corrosion treatment trouble. The main external corrosion of the question is very important, the quality of its external anti-corrosion directly affect its service life. Now the main external steel pipe corrosion: concealed type approach, on the steel pipe are requested to strengthen or special enhanced external corrosion, in some areas to promote cathodic protection. On the concealment type of external corrosion method is usually paint, such as petroleum asphalt, epoxy coal tar pitch, which is not easy to cure at low temperatures, and welding construction in the field more questions, originally ...

    Causes of ASTM A53 seamless steel tube crack:     First, the reasons for the tube (round) mostly, the internal contains more cracks, inclusions, air bags and so on. Uneven organization of the tube is the reason, pay attention to the choice of the implementation of tube standard, there is a certain size of the manufacturer of the round bar on the line.     Second, the perforation temperature, process adjustment can not be ignored, if the piercing temperature is low, improper adjustment, can also cause the tearing of the capillary tube internal organization.     Third, the finish annealing temperature is suitable. Perforated heating temperature 1180 ~ 1230 ℃, low, this is the temperature of carbon steel, take 1230-1250 was appropriate. Furnace time is generally more than 60min

    In all steel pipe, ASTM A53 seamless steel tube occupies a large proportion, but the actual production of seamless steel pipe is often used in controlled rolling and cooling technology, easy to control the process of cooling due to uneven cooling plate defects, seriously affecting product quality and contract cash . Plate side wave is one of the more serious one.     Seamless steel tube side of the wave-shaped defects are due to uneven cooling caused by lateral. On-site tracking found that there are obvious on both sides of the side wave plate "band-shaped supercooled" area. The transverse cooling caused by uneven factors are:     1) There are transverse temperature differences between the center and the sides of the seamless tube.     2) seamless steel pipe in the controlled rolling process, the middle and edge there is a large temperature difference.     3) The finish rolling mill adopts "CVC" rolling process, which is cau...