The Technology And Application Of High Precision Cold Drawn Steel Tube
The Technology and Application of High Precision Cold Drawn Steel Tube
High precision cold drawn precision steel tube is a new type of high-tech energy-saving products. In recent years, the use of this technology in the production of precision steel tube has been widely used in domestic hydraulic, pneumatic cylinder, coal mine bracket (pillar), oil pump pipe, jack and other manufacturing areas. The application of high precision cold drawn precision steel tube do good to steel saving, improve the machining efficiency, save energy and reduce the hydraulic cylinder, and it has important significance to cylinder processing equipment investment.
Cold drawn method: production of high precision cold drawn pipe, compared with traditional cutting technology, the hydraulic cylinder has the following characteristics: (1) high efficiency: with the traditional method to produce a cylinder with 420mm inner diameter and 12 meters long should be 154 hours, with cold drawn method production only 4 minutes. (2) high rate of graded products: due to the effect of rolling pressure head of bore hole, in the process of cutting, the blank pipe due to the weight of the deflection, the deviation of the rolling and boring cutter will happen which will cause waste. And the functions only around 60%, and with cold drawn method production, functions can reach more than 95%. (3) high utilization rate of metal: made of traditional method of boring cylinder body, metal utilization only 50-70%. When using a method of drawing production, the metal utilization rate can reach 95%. (4) can improve the mechanical properties of the finished tube metal: production by drawing method, make the blank gets more than 30% of the plastic deformation, due to work hardening, has greatly improve the strength of the finished tube metal limit. Generally in the finished tube layer, strength limit can increase 60%. High precision cold drawn pipe is made of seamless hot-rolled steel pipe and straight seam welded pipe as blank, after chemical treatment on the special cold drawing machine, through the special deformation principle of design of mould drawing, produce high precision tube. The dimensional accuracy can reach H10 ~ H8, straightness of 0.35 ~ 0.5 mm/m, the surface roughness Ra1.6-0.4.
Production process is as follows: feed - appearance inspection - mechanical cleaning - annealing - straightening - tube processing - pickling - neutralizing - water scrubbing - scale change - saponification - drawing - check - cut to length - honing - end processing - straightening - assembly - testing - packing
Application:(1) engineering hydraulic machinery: such as hydraulic truck crane, excavator, bulldozer, forklift, etc. (2) coal mine hydraulic support: at present, the national production has 48 enterprises for manufacturing downhole hydraulic support, the total demand of the high precision cold drawn pipe is about 1.2million meters. (3) hydropower station gate crane machine, template, especially in the Yangtze river three gorges project is a big demand in the next decade. (4) construction machinery: the lifting machinery for work high above the ground, general building construction repair is also inseparable from the hydraulic machinery. (5) petroleum geology pipe : oil fields all over the country each year need to pump more than 30000 units, annual consumption of high precision tube is more than 20-40 meters, also can use this technology finishing all kinds of drill pipe. (6) arms industry: military departments now use guns tube spinning method processing, spinning method is low productivity and high cost, production is more appropriate in cold drawing way. (7) bearing industry: currently, the production of the rolling bearing race is with round steel as raw material, the slice through stamping. Large bearing race will be hollowed to make solid bar, metal utilization rate is less than 40%, it is an urgent need of high-precision bearing steel thick wall pipe. (8) automobile industry : In the year 1995, the precision tube is 6000 tons, axle tube 10000 tons and a variety of pipeline, etc. (9) aviation industry: aluminum alloy aircraft landing gear and thick wall steel pipe, etc. (10) jack: jack manufacturing in China has considerable strength, good prospects to earn foreign exchange through exports. Our production enterprises at present adopt solid bar to process jack with low production efficiency and high material waste, and there is an urgent demand for high precision cold drawn pipe. (11) other areas: all kinds of printing roller, roller roller tube, stainless steel pipe, aluminum pipe, copper pipe, special pipe and the inner and outer pipe, and so on can be produced by this technology.