Main technical measures for low hardening trend
Gas and other projects.
.With the dissolution of the steel coil surface, the contents of iron, the solution will gradually lose its polishing ability. In any case, increase the temperature, turn on the current and equalize the force. For the analytical solution, it indicates that the solution has been aged. There are two options for the regeneration of polishing solution and the restoration of polishing ability. When the solution is diluted with water to reduce the acidity, impurities such as iron, chromium and nickel can be locally precipitated as salt, and the precipitation at the bottom of the tank can be removed, and then heated and evaporated to remove water, so it is cumbersome to restore the original relative density which requires a large consumption of energy and time. The other is to replace part of the solution, so as to retain 20% of the old solution and supplement 80% of the new solution. It can be polished with little or no power.
Generally, the wall thickness of coiled pipe is 20mm and the outer diameter is 450-
.: 90% of the developed thick wall coil processing industry is CNC cutting machine, of which the proportion of NC plasma cutting is small. In industrial production, the thermal cutting of thick wall coiled pipe generally includes gas cutting, plasma cutting, laser cutting and so on. Among them, plasma cutting has a wider cutting range than gas cutting More efficient. Fine plasma cutting technology is close to laser cutting in material cutting surface quality, but the cost is much lower than laser cutting. Therefore, since the successful development of the United States in the mid-1950s, plasma cutting has developed rapidly. Professional hot-rolled steel pipe, large-diameter thick wall rolling pipe, thick wall straight seam rolling pipe, steel casing, rolling pipe factory, high pressure rating, good waterproof performance, strong overload capacity, corrosion resistance, radiation protection and long service life. With the rapid development of computer and digital technology, NC cutting has also expanded and improved the processing accuracy. It shows great advantages in saving materials and improving labor productivity. This leads to the development of plasma cutting technology from manual or semi-automatic to NC, which has become one of the main directions of NC cutting technology. NC plasma cutting technology is a set of high-tech technologies such as NC technology, plasma cutting technology and inverter power supply technology. Its development is based on the common progress of computer, plasma arc characteristic research, power electronics and other disciplines. The CNC cutting technology began in the 1980s, and the CNC plasma cutting technology was later. However, recently, research institutes and manufacturers have studied NC plasma cutting technology and gradually developed and produced various specifications of NC plasma cutting equipment, narrowing the gap of foreign advanced technology. The large-scale rolling pipe factory of rolling pipe, t-welded rolling pipe, flaw detection welding rolling pipe, 16Mn rolling pipe, Q345B rolling pipe and special-shaped rolling pipe, and the t-welded rolling pipe,Q345B welded steel pipe, 16Mn rolling pipe, Q345B rolling pipe and special-shaped rolling pipe produced by the rolling pipe factory are exported to major engineering buildings at home and abroad.
API seamless steel pipe is expressed as outer diameter, wall thickness and thick wall seamless steel pipe, which is mainly used for machining, hydraulic steel and other purposes. Classification of thick wall seamless steel pipe & mdash& mdash; Hot rolled thick wall seamless steel pipe, cold rolled thick wall seamless steel pipe, cold drawn thick wall seamless steel pipe, thick wall seamless steel pipe, stainless steel seamless steel pipe for pipe jacking structure (GB / t14975-199) are widely used in corrosion-resistant pipes and structural members in chemical, petroleum, light textile, food, machinery and other industries, and stainless steel hot rolled () and cold drawn (rolled) Seamless stainless steel pipe for fluid transportation (GB / t14976-199) is a hot-rolled (extruded) and cold drawn (rolled) seamless steel pipe made of stainless steel for fluid transportation.
Separate & ldquo; Hot coil & rdquo; The word is a noun, which is the abbreviation of hot rolled coil, and the hot coil used here to connect with thick wall steel pipe is a verb, indicating a kind of behavior.
Extend the length of the part: 566, divide it into 24 equal parts, symmetrical, and the length of each bisector from the middle to the side is: 11 110 106 10 93 84 75 66 57 0, 50 44 40 39 2.
Large diameter thick wall coiled pipe is usually higher than dn450. Large diameter thick wall coiled pipe sometimes has two welds. The reason why this happens is mainly because of raw material problems and equipment processing. Steel mills usually do not produce steel plates with the required width of large-diameter welded pipes required by customers. Therefore, two plates need to be welded, so welds will occur. Large diameter thick wall coiled pipe can mainly carry out flaw detection, and the requirements related to delivery are wider than other products. Ultrasonic flaw detector is mainly used to detect large-diameter thick wall coiled pipe. The same circular joint of coiled pipe shall not be greater than 2.
The longitudinal weld of the same barrel part of the coiled pipe shall not be greater than 2.
Development Curriculum.Deviation reel as follows (unit: mm): nominal diameter & amp; amp; lt; 800 800 to 1200 1300 to 1600 1700 to 2400 2600 to 3000 perimeter Deviation & plusmn; 5± 7± 9± 11± 13 ovality is 1% of the outer diameter, 4 6 8 10 and no more than 4 steel plate coils have standards. At present, we carry out construction according to the acceptance of standard GB / t19793-92.
After, we should prevent the surface damage of the plate. The parts with serious scars must be grinded to make transition, and the wall thickness of the grinded part shall not be less than the design wall thickness. Steel rolling pipe is an unconventional pipe, and there is no domestic standard at present. Therefore, the inspection is mainly aimed at the thickness and weld quality.
During the plate crimping process, the steel plate can be sandblasted to eliminate the iron oxide scale on the surface of the steel plate and ensure the raw materials on the cylinder surface during the processing process.
Deviation reel as follows (unit: mm): nominal diameter & amp; amp; lt; 800 800 to 1200 1300 to 1600 1700 to 2400 2600 to 3000 perimeter Deviation & plusmn; 5± 7± 9± 11± 13 ovality is 1% of the outer diameter, 4 6 8 10 and no more than 4 steel plate coils have standards. At present, we carry out construction according to the acceptance of standard GB / t19793-92.
Create brilliance.Columns for bearing steel structures such as offshore platforms, super long-span building structures and electric pole tower and mast structures requiring wind resistance and earthquake resistance. Inspection equipment maintenance and packaging strategy: 16Mn thick wall coil adopts PLC automatic system, and all parts of Shenzhen thick wall coil focus on panel operation. The cutting length of 16Mn thick wall coil adopts photoelectric induction, accurate positioning and automatic cutting. Each working process adopts double pump oil pressure system, Shenzhen thick wall coiled pipe has good cutting synchronization performance. 16Mn thick wall coiled pipe has different application ranges: length: 0-1400mm, thickness: 2-15mm, diameter: 20-200mm, application voltage: 380V 50Hz. It is used according to the specified parameters and range to ensure that it can play an important role and value in use. The packaging process of new product 16Mn thick wall coil includes main processes such as filling, wrapping and sealing, as well as related pre and post processes such as cleaning, stacking and disassembly. The process of 16Mn thick wall rolling pipe shall be strict, and it shall be produced in the correct way and principle. In addition, the process of 16Mn thick wall coiled pipe also includes measuring or stamping on the package. The use of mechanical packaging products can improve productivity, reduce labor intensity meet the needs of large-scale production, d7z3xjb87v21w and meet the requirements of cleanliness and hygiene. The production process of rolling pipe is round pipe blank → Heating → Perforation & rarr; Roll cross rolling, continuous rolling or → Off pipe & rarr; Sizing (or reducing) → Cooling → Straightening & rarr; Hydrostatic test (or flaw detection) → Mark & rarr; According to different production, warehousing supply indicators can be divided into hot-rolled pipe, cold-rolled pipe, cold drawn pipe pipe, etc. quality management? Hot rolled seamless tubes are produced on the automatic tube rolling mill. The solid tube blank is cut into the required length by removing the surface defects. The Shenzhen coiled tube is centered on the end face of the perforated end of the tube blank, and then sent to the heating furnace for heating. It is perforated on the piercing machine. At the same time, it rotates and advances continuously. Under the action of the roll and top head, a cavity called rough tube is gradually formed inside the tube blank, Then it is sent to the automatic pipe mill for continuous rolling, and the wall thickness is adjusted by the whole machine. The Shenzhen coiled pipe is sized by the sizing machine to meet the specification requirements. The production of hot-rolled seamless steel pipe by the continuous pipe mill is relatively advanced. If you want to obtain seamless pipe with smaller size and better quality, 888yixtfrfsbu Shenzhen coil pipe must be cold rolled and cold drawn or a combination of the two. The cold rolling is usually carried out on the roll mill. The steel pipe is rolled in the annular pass composed of variable section circular hole groove and fixed conical plug. The cold drawing is usually carried out on the single chain or double chain cold drawing machine, that is, the heated pipe blank is placed in a closed cylinder, and the perforated rod and rod move, Professional hot-rolled steel pipe, large-diameter thick wall rolling pipe thick wall straight seam rolling pipe, steel casing, rolling pipe factory has advanced technology, strict testing, more affordable price and more preferential. Welcome to consult. Make the parts extruded from the smaller die hole. This method can produce the steel pipe with smaller diameter. Work course standard requirements & amp; amp; quot;Standard requirements: the Executive Standards of hot-rolled thick wall coil product line are: GB / t50205-200, GB / t3092-2001, etc.
The groove sizes of longitudinal seam and circumferential seam of hot-rolled thick wall coiled pipe are different. Therefore, before plate rolling, it is necessary to confirm whether the inner side is upward to ensure the correctness of groove direction.
1 carbon structural steel: q215-a, q215-a. & middot; F,Q215-BQ215-B· F,Q235-A,Q235-A· F,Q235-B,Q235-B· F. Q235-c ordinary carbon steel: B2 BY2 B2F by2f B3 by3 B3F by3f a2ay2 a2f ay2f A3 ay3 A3F ay3f2 high quality carbon steel: 10 15 20 transmission shaft steel 3 low alloy structural steel: 123mn 16Mn 19mn 08ti 10ti15ti4 special purpose steel plates are stacked in the open air to prevent rain from causing steel plates. The oxide scale falling off the surface of steel plates is easy to turn into blocks or clusters and adhere to steel plates or crimping rollers, When repeatedly pressed, the coiled pipe forms pit defects.
.Circumferential deviation of coiled pipe, pipe groove processing and joint pair: when the pipe wall thickness is less than 6mm, it is type I weld; when the pipe wall thickness is greater than 6mm, it is type V weld; For pipes with diameter greater than 600mm and wall thickness greater than 6mm, the bottom of the pipe shall be sealed at the bottom of the pipe; In addition to the lap joint, the other type of gas coil pipe is continuous and solid V-groove butt welding. If the weld is found to be defective, the weld must be re welded. Rewelding shall not be more than twice. Long term supply of hot rolled steel pipe, large diameter thick wall rolling pipe, thick wall straight seam rolling pipe, steel casing, rolling pipe factory has complete products and excellent quality, The price is favorable. The longitudinal weld of the winding pipe with the same cylindrical part shall not be greater than the spacing between two longitudinal joints shall not be less than 200mm. The arc length of the winding pipe calibration template shall be 1 / 6 ~ I of the circumference of the pipe / the gap between the template and the pipe. Let me introduce the steel plate production standard winding pipe. During the winding process, the surface of the circuit board shall be protected from damage. Parts with severe scars shall be ground to achieve transition, and the wall thickness of the ground part shall not be less than the design wall thickness.
It has advantages and quality. The weld reinforcement obtained is increased, the weld formation is deteriorated and the edge transition is poor.
The main purpose of preheating is to reduce the cooling rate of welded joints and preheat temperature. As can be seen from the table preheating can reduce the cooling rate, but basically does not affect the time spent at high temperature,45# reel, which is ideal. Therefore, when welding thick wall coils with hardening trend, the main technical measure to reduce the cooling rate and hardening trend is preheating rather than increasing the line energy. Plasma cutting of thick wall coiled pipe is more effective than gas cutting