1, Ultrasonic flaw detection equipment The flaw detection machine used MultiUltra-04 four-channel ultrasonic digital flaw detector, the instrument is based on the windows platform, a powerful report document processing capabilities, user-friendly control interface, high operational performance. Software configuration is modular, can be configured according to need, and reserved for encoder 16 into / 16 out I / O interface. Instrument circuit design and manufacturing advanced technology, reliable performance, high signal-to-noise ratio, defect resolution ability, gate alarm function, work stability. It is designed for automatic testing of thin-walled seamless steel tubes designed ultrasonic testing equipment.   2, Steel pipe delivery system Steel pipe conveying system includes: automatic feeding, automatic feeding, automatic delivery, qualified products and unqualified products such as automatic sorting device. The steel pipe is automatically turned into the conveying roller by the loading platform, the testing steel pipe is put into the front pressure roller through the conveying roller and enters the flaw detection host inspection, the steel pipe is output by the rear pressure roller into the conveying roller after the flaw detection, and the pipe can be automatically After the test steel pipe into qualified products and substandard products rack.   3, Ultrasonic flaw detection host Ultrasonic flaw detection main machine includes: Ultrasonic probe rotating tank, guide sleeve, front and rear rotating pressure roller and other components. Ultrasonic probe rotating tank placed on the stainless steel platform, the rotary tank configuration probe disk, according to 90 degrees to install four sets of ultrasonic line focus probe and probe adjustment device, the pipe can bidirectional flaw detection, when the testing specifications change, should be adjusted stainless steel platform as a whole body lifting mechanism so that the ultrasonic probe rotating tank, guide sleeve, both sides of the front wheel press roller and conveyor roller center axis line.   4, Electrical control system Flaw detection machine adopts modern AC motor speed control technology for speed control, so that the host on both sides of the roller speed and rotary pressure wheel speed variable adjustment to meet the needs of different detection speed, peripheral lines and simple, beautiful appearance. As a result of AC motor, compared with the old DC motor speed control technology, with a simple motor structure, no spark interference, reliable performance, easy maintenance and repair. Tilting control panel panel tilt structure, the bottom of the cabinet is equipped with a caster to facilitate the operation and movement, the installation of two AC motor speed controller inside the cabinet and related circuits, and installed in the bottom of the cabinet cooling fan. Panel buttons and switches with new, beautiful and highly reliable components, and install the indicator header, the header can be read indirectly from the detection of the current steel detection speed.

High-frequency welded pipe production process depends mainly on product variety, from raw materials to finished products need to go through a series of processes, the completion of these processes require a corresponding variety of mechanical equipment and welding, electrical control, testing devices, these devices and devices according to different processes. The process requires a variety of reasonable arrangements, the typical process of high-frequency welded pipe: unwinding - strip leveling - head and tail shear - steel butt welding - looper storage - forming - welding - removal of burrs - sizing - flaw detection - initial inspection - steel straightening - pipe processing - hydrostatic testing - flaw detection - printing and coating - finished products. High-frequency welding is the use of high-frequency current flowing through the continuous contact surface of the workpiece due to the heat generated by the heat and the application of the top forging force, the workpiece metal to achieve a mutual welding of a class of welding methods. It is similar to normal resistance welding, but there are many important differences. High-frequency welding has a large power supply, for different materials, caliber and wall thickness of the pipe can reach a higher welding speed (higher than the maximum welding speed of argon arc welding lO times higher). Among them, raw materials accounted for 32.44%, welding process accounted for 24.85%, roll adjustment accounted for 22.72%, the three accounted for 80.01%, is the main link. If the induction ring away from the squeeze roller farther, the effective heating time is longer, heat affected zone wide, making the strength of welded steel pipe decreased or incomplete penetration; the other hand induction ring easy to burn squeeze roller.

Galvanized steel pipes are used in some construction sites, but galvanized steel pipes may rust for long periods of time. Galvanized steel is the use of cold-rolled or hot rolled steel plate technology will be narrow and long plate coated with a layer of zinc, divided into hot-dip galvanized and electro-galvanized, hot dip galvanized coating more uniform, strong adhesion and long service life. The chemical reaction with the bath can make galvanized steel pipe corrosion resistance, even if there is a strong corrosion resistance, rust or the phenomenon of the process will occur, then, what is the reason for this? Galvanized steel rust is the main reason that the surface layer of zinc plated. Zinc is relatively active in chemistry, soluble in both acids and alkalis, and chemically reacts with zinc in humid environments to form a basic zinc carbonate membrane on the surface. In contact with substances containing hydrogen sulfide, the zinc resistance corrosion decreased, easily corroded, exposing the steel surface, the final rust. Galvanized steel with a lower probability of rust, because the coating is relatively thick galvanized steel, not easy to cause the oxidation of steel, it is not easy to rust.

1, Different processing technology: Seamless pipe is made of high-quality carbon steel or alloy steel. Seamless pipe processing technology is divided into two kinds of cold drawn and hot rolled, while the seam is generally welded. 2, Different uses: Seamless pipe is mainly used for transporting fluid pipes or structural parts, mainly for the mechanical industry, while the seam steel pipe is mainly used in the construction industry, such as water, gas, compressed air and other low pressure fluid. However, the pressure pipes are used seamless steel pipe. 3, Different prices: Because the production process of seamless steel pipe is more complicated, the price is more expensive than that of seamed steel pipe, while the seamed steel pipe is mainly made of secondary welded steel plate (steel strip), the price is cheap, the use is also relatively wide. 4, To withstand different pressures The seam pipe is generally able to withstand the maximum pressure of 20 kg, which is the safest use. It is generally used for water, gas, compressed air and other low-pressure fluids; seamless pipe can withstand ultra-high pressure, of course, its wall thickness will increase, which need to be designed according to the pressure requirements. It is generally used for high pressure tubing, boiler tubes and other high temperature and pressure equipment. There are also structural seamless pipes, which look at the design requirements.  5, Heat treatment changes At present, there are also some pipes with seamless steel pipe seams that anneal the weld seam and eliminate the residual stress of the weld seam, making the weld seam equal to the base metal. The bearing pressure range is basically equivalent to that of the seamless pipe. Also consider using. Of course, there are also some on the market using seamless steel pipe with drawn steel pipe after overall heating or drawing with core head rolling, which is mainly dominated by small sizes. Such pipes are only in the shape of seamless pipe, and its essence is not very it is good.

In many occasions, people use more alloy steel instead of carbon steel. The reasons are mainly as follows. (1) Poor hardenability of carbon steel After carbon steel is quenched with water, its critical quenching diameter is 15-20mm. For parts with a diameter larger than 20mm, it is impossible to quench through water quenching, and the comprehensive mechanical properties of the whole cross section can not be guaranteed. Therefore, for demanding large parts, carbon steel is certainly not applicable. The alloy steel with high hardenability, can be used for the manufacture of large cross-section, the shape of complex parts. (2) Low temperature strength of carbon steel, red hardness is poor Carbon steel at temperatures above 200 ℃, the intensity and hardness will soon be reduced. The alloy steel after tempering good stability. Red hard, can work at higher temperatures. (3) Carbon steel can not achieve good overall performance For example, when tempering treatment is attempted to obtain good overall performance, the toughness is lower if higher strength is to be ensured and the strength is lower if better toughness is to be ensured. This is due to the poor stability of carbon steel tempering. Therefore, the overall performance of carbon steel obtained alloy steel is far worse, that is, alloy steel has good toughness. (4) Carbon steel does not have special properties For example, the requirements of high temperature hardness or tension, oxidation resistance, corrosion resistance, special electricity, magnetic properties, can not be obtained with carbon steel, steel can only be selected to meet the above requirements.