The development of the progress of aviation industry and hydraulic press of heavy-duty die forging is inseparable. During World War II, germany was German plane to offer large block mould forging in the progress on technology of hydraulic press of heavy-duty die forging, improved performance of its opportunity for combat greatly. Get this inspiration, after this United States, Russia and France developed heavy-duty aviation to use die forging hydraulic press in succession. Up to now, the hydraulic press of heavy-duty die forging of the 300MN above that the whole world already built go into operation in all 18. Among them the United States 7, the biggest tonnage is 450MN; Russia 6, the biggest tonnage is 750MN; France 2, the biggest tonnage is 650MN, still have 2006 the hydraulic press of a 400MN of put into production; In addition, england, Australia and China each 1, tonnage all is controlled in 300MN. The development of aviation industry cannot leave hydraulic press of heavy-duty die forging is the fact that does not dispute, hydraulic press of our country's only die forging of aluminium alloy of a 300MN cannot satisfy the development requirement of contemporary aviation industry already. Be in early 2002, the Chinese Academy of Engineering held water to be advisory research group of the group leader with academician Mr Shi Changxu, build hydraulic press of die forging of 80 thousand T to undertake survey to our country. Research thinks our country shows level to start construction hydraulic press of die forging of 80 thousand T is large equipment project, very necessary to the industry such as industry of vessel of aviation, ship, spaceflight, enginery, nucleus and completely feasible. Want to develop own aviation industry in our country, below the big background that be developed independently and makes large aircraft, china 2 weigh and base of industry of aviation of Xi'an fine thing gate of a lane parts project approving 80 thousand T and project of hydraulic press of die forging of aviation of 40 thousand T, offer forging of high grade model of large whole aviation for manufacturing industry of our country aircraft. However the design of hydraulic press of heavy-duty die forging and make facing tremendous difficulty and risk, the its treatment, difficulty that make and carries is in ultimate position, and investment is huge, cycle is long. To solve afore-mentioned problems, the research that designs to structure of heavy-duty hydraulic press and improve never had stopped. Hydraulic press of the earliest heavy-duty die forging uses a convention generally " 3 Liang Sizhu " structure, and frame is frame of blame prestressing force, the typical delegate of this kind of structure is the hydraulic press of 750MN die forging of Russia, because its bear the weight of,the structure lacks prestressing force protection, material is allowable force is 40 ～ 60MPa only, bring about structural dimension and weight thereby very giant, gross weight achieved 26000t, and use heavy-duty cast and forging in great quantities, treatment production difficulty is great, fatigue performance is not high. 20 centuries 70 time, appeared thick bolt tightens a structure beforehand, this kind of structure is used a few thick bolt to bearing the weight of frame brings to bear on to tighten force beforehand, of material allowable stress is able to rise to 100 ～ 150MPa, fatigue function also rises somewhat. Because large prestressing force is thick the difficulty that bolt creates is great, and allowable stress shoulds not be too tall, after this appeared again fine bolt tightens a structure beforehand, replace with many fine bolt a few thick bolt brings to bear on to tighten force beforehand, make thereby allowable stress rises to 150 ～ 200MPa. Even if is such, the design of heavy-duty hydraulic press still faces tremendous difficulty and risk. Prestressing force steel wire twines technology and analyse cent - the development that bank combines a technology solved this problem greatly, its are basic train of thought is will heavy-duty bear the weight of structure -- dimension and weight are giant, the heavy-duty spare parts that traditional method machines hard, analyse cent is much stature, reduce production difficulty and risk thereby, convenient carry; Twine a technology through prestressing force steel wire next, add up to connective means in order to pit to be its combination a whole, replace structure of integral casting forge thereby. The generation of train of thought of this kind of technology, reflected adequately " with small wrestle big " characteristic, it is the method of design of heavy-duty hydraulic press that has innovation sex. Since 2006, tsinghua university breaks through traditional thinking on the design of heavy-duty hydraulic press, use prestressing force steel wire to twine technology and bank to added up to a technology to design the heavy-duty hydraulic press of above of much stage 300MN early or late, include among them already the biggest 360MN/150MN steel tube on the world of put into production is perpendicular extruder group, in the 400MN aviation nicety that build die forging hydraulic press is mixed hydraulic press of forging of report of nucleus of 300MN of elder brother hill. The article is setting with aviation industry, introduced bank to close the technical application on hydraulic press of aviation die forging. Analyse is divided - bond and analyse cent - bank adds up to 1 analyse to divide - bond structure adds up to a technology to appear in bank previously, child the means that combination all uses key and keyhole to cooperate will prevent child the fault between moves and bear shearing stress, child through bolt combination is a whole. The problem with this kind of most serious structure is the stress concentration of keyhole, in bear when shearing stress, be out of shape as a result of keyhole and make shearing stress appears to center all round keyhole, make crackle is produced easily and expand, it is fluky that the structure of high bond proves in practice. 20 centuries of Shanghai the sill of hydraulic press of free forge of 60 time 120MN is self-prossessed 540t, ever designed the component that it is analyse - bond structure, but final structure of electroslag welding of instead of this kind of method. 2 analyse are divided - bank adds up to a structure alleged analyse is divided - bank adds up to a structure, be will child analyse undertakes pitting closing changing handling on cent face, treatment becomes multimodal structure, be in child between add softer intermediate bolster plate (bank plywood) , traverse powerful prestressing force field, the multimodal that makes analyse divides a face to go up forms not reversible multimodal flush type mounting between structure and bank plywood, this kind of structure is out of shape through not reversible plasticity implementation, increase thereby child on analyse cent face fight cut capacity. Check a proof through the experiment, bank adds up to what join can achieve to fight cut coefficient (bank adds up to coefficient) very more than tower above of coefficient of friction, can achieve 0. 6 above, enough cuts the demand of ability to fighting on contented project. Nextpage analyse is divided - bank joins hydraulic press of die forging of technology and aviation of 400MN of hydraulic press of 400MN aviation die forging is the crucial equipment that produces large, crucial forging for industry of our country aviation, its design achieves international advanced level. This press uses 60MPa pump system of straight drive hydraulic pressure, suppress speed achieves 60mm/s, use 8 crocks of synchronism to balance a system, the horizontal precision of moved cross beam of real time adjustment, design eccentric throw is 200mm, in bear bigger slant the figuration precision that component still can assure when carrying, assure to realized accurate die forging to offer. Frame is the most important construction part in heavy-duty hydraulic press, it is tremendous energy gathers, the carrier that deliver and releases, the intensity that its design, stiffness and reliability are very fundamental. The frame of hydraulic press of 400MN aviation die forging uses vaulted roof beam + the way that pays bridge, arched girder and pillar are divided to be by analyse respectively 5 stature, whole frame in all 20 stature, odd weight all is under 80t, reduced sheet greatly weight and production difficulty. Each stature the analyse cent face between closes through bank change processing to raise its bank to add up to coefficient, bring to bear on through steel wire powerful prestressing force field will 20 stature twine become a prestressing force bear the weight of frame, the weight of this frame is 1400t left and right sides, if use traditional production method, difficulty is great. Use " with small wrestle big " prestressing force analyse is divided - bank combines a technology is to make this kind heavy-duty bear the weight of the effective technology course of frame. In our country steel wire of first prestressing force twines analyse to divide - bank joins press -- in 360MN perpendicular extruder, undertook to arched girder analyse is divided only - bank closes, and divide only for 3 stature, child between the multimodal structure that uses processing rolling a flower to form bank to close, . And pillar uses section to cast, solder next for a whole. This kind of structure is relatively traditional " 3 Liang Sizhu " type press, had reduced greatly on production difficulty, because pillar is,solder however integral structure, its weight still is in 200t above. To reduce production difficulty further, prove adequately in the course, after be being calculated through exact numerical value especially, (contrary column analyse is divided - the frame after bank closes undertakes finite yuan of analysis, to all sorts of probable condition, include central load, around to slant carry, the left and right sides slants carry etc have consideration) , discovery adds up to coefficient in bank for 0.
3 when, part arched girder and pillar analyse cent is 5 stature, below effect of powerful prestressing force field, the fault that analyse won't produce to divide a face to go up when press works moves and part, analyse is divided - the frame that bank adds up to and integral frame are had be out of shape identically harmonious sex. Slant when carrying, although be over to direct through pillar completely,bear side thrust, bank adds up to what the face still keeps enough to fight cut capacity. The practice of 360MN extruder and sufficient theoretical analysis were the design of press of die forging of aviation of our country 400MN to provide scientific basis, heavy-duty bear the weight of the design development of frame gave a brand-new technical line. Divide to analyse - the knowledge that bank combines a technology and application are a process that deepens ceaselessly in theory and practice, up to now, application is won in the large part that bank combines a technology to had waited for hydraulic press in heavy-duty frame, heavy-duty moved cross beam. 1 of hydraulic press of 400MN aviation die forging: Hydraulic press of die forging of aviation of 400MN of 10 model test is hydraulic press of 400MN of on the world first one-cylinder, it is pillar cent first 5 stature use bank to close link, advocate the hydraulic pressure jar that the crock uses prestressing force steel wire to twine, prove through theoretical analysis and numeric computation program of this kind of technology is feasible. And model test is test and verify of its dependability the most essential assure, the to load pumping station that designs through proper motion is right advocate crock and frame undertake to load experiments, analyse its displacement and field of stress meet an emergency, figure according to similar principle actually the displacement of content and field of stress meet an emergency distributing. The experiment proves, prestressing force analyse is divided - the application that bank closes a structure to go up in hydraulic press of 400MN aviation die forging is reliable. Last word the article is setting with aviation industry, elaborated the relation of hydraulic press of heavy-duty die forging and aviation industry, design the difficulty of an existence in the light of traditional heavy-duty hydraulic press, the prestressing force analyse that introduced Tsinghua university invention is divided - bank combines a technology, elaborated its connotation to reach its to be in our country the application on hydraulic press of newest 400MN aviation die forging. Carry out a proof, prestressing force analyse is divided - bank combines a technology is a feasible heavy equipment that has innovation sex makes technical line, solved heavy equipment to design medium issue well, reduced production difficulty and risk, raised the dependability of equipment, it is the important contribution of counterpoise equipment industry, be sure to boost the level that whole of forging of model of our country aviation forgings greatly at the same time. CNC Milling
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