Raise machining to produce the way of efficiency

Want to improve machining efficiency, must shorten the time of every process that constitutes process. Undertake an analysis through constituting an element to the time of working procedure process, can seek the way that raises treatment working procedure to manufacture efficiency, achieve the goal that improves treatment efficiency finally. The treatment of mechanical spare parts often needs to adopt much talk working procedure, change its appearance, size gradually, raise its precision, want to pass machining production to give more eligible parts inside unit time so, must shorten the time of every working procedure. Seeking the way that raises working procedure to manufacture efficiency is to rise to be machined a base that produces efficiency and jumping-off place. The time ultimate analysis of working procedure process 1. Odd the time that some be been in by treatment spare parts experiences a floor-to-floor time inside line working procedure is called the sheet of this spare parts floor-to-floor time, basically comprise by element of the following time: (1) basic time Tb: The time that place of spare parts of machine tool cutting needs, if get,cut, the time that the cutting process place such as milling, boring and grinding spends. (2) auxiliary time Ta: The time with normative treatment of actuate and the time changing a knife that includes form of cutting of time of next makings time on workpiece, cutting tool advance and retreat, change, time that quit a machine tool, change and measure time to wait. (3) Tc of technical serve time: Include to change the time that uses blunt cutting tool, in producing a course corrective, adjust equipment / tool / clamping apparatus / the time of the mould, lubricant equipment time, treatment interrupts add on cleaning equipment and clamping apparatus cut bits and flotsam time to wait, it is period of time of will whole work commonly (be like every) these time are accumulated rise again apportion goes to every to be gotten on by treatment spare parts. Graph 1 crankshaft car - car broach provides (4) Tg of constituent serve time: Get after the class before including a class, change reach clear away labour (knife) provided time, examination and try moving equipment time, add change cutting fluid and the time that work place, cleaning equipment cleans before coming off work. This time also is to be in in number of a work after accumulative total again apportion. (5) physiology need and breathing space Tn, this time also needs to be after an order accumulative total again apportion. Odd floor-to-floor time is afore-mentioned each time the sum, namely: T0=Tb+Ta+Tc+Tg+Tn. Calculating actual sheet when floor-to-floor time, calculate to simplify, often mix need apportion to the Tc of every spare parts, Tg Tn uses the percentage that holds basic time and auxiliary time the sum (β ) will calculate, namely: T0= (Tb+Ta) (1+ β ) . The size that β is worth and equipment and scale of production are concerned, in shedding water production in great quantities commonly, take 0.

05 ～ 0.

1, in be being produced group by group, take 0.

1 ～ 0.

2, in sheet take in pre production 0.

2 ～ 0.

25. Odd T0 does not include a floor-to-floor time: This process equipment changes breed or the equipment settling time that modificatory working procedure needs; Because produce condition of organization, technology undesirable the time loss that causes accidentally with the job, appear temporarily like equipment, tool breakdown, manufacturing organization appears to be not coordinated temporarily (if shutdown waits for makings, personnel not to attemper,reach the designated position etc) , the worker falls ill temporarily, be late to wait with leave early; For repair substandard products or the time that make the spare parts place that replaces waste product cost. Outside dividing settling time, other and random the time that happen all not plan enter sheet floor-to-floor time, go in this part-time loss consideration through machine load rate however. Nextpage2. When settling time Tj and valuation time Tp are being produced group by group, the spare parts is machined or an equipment assumes many breed same when the much talk working procedure of kind of spare parts, change every time when breed or working procedure, the moving parameter that needs pair of facility, program, uses cutting tool, clamping apparatus and complementary undertake change and be changinged, the machining complex that needs to be formed to this equipment place undertakes adjustment, undertake trying cutting to spare parts of new breed, new working procedure, in order to achieve the treatment requirement of new breed spare parts or new working procedure, this is the content that place of equipment settling time contains. Graph settling time of bit body of the mill outside 2 crankshaft is being machined only new before approving a part, arise, this time also answer apportion approves every spare parts to go up to this. Apportion time has immediate concern besides the accident with settling time outside, how many also have immediate concern with the amount of every batches of spare partses and batch. The batch of reasonable and certain investment (N) it is very important, devoted batch is overmuch, every batches of parts are too little, can make the settling time of apportion of place of every spare parts overmuch; If devoted batch is too little, batch is too big, can cause pass in goods keep long in stock much, make production cost raises. The sheet of the spare parts the settling time the sum of floor-to-floor time and apportion of place of this spare parts is the spare parts is in the valuation time of this working procedure, namely Tp=T0+Tj/N. What valuation schedule shows is the time that is had on the equipment of this working procedure by treatment spare parts. From this calculable the facility amount that gives this working procedure to book creed to should be deployed to finish. The place before be like is narrated, to onefold water product line or product line of mixture breed water, tp=T0, namely valuation time and sheet time is same. By afore-mentioned analysises knowable, want to raise treatment working procedure to manufacture efficiency, should try to shorten composition is odd the each composition element of a floor-to-floor time and valuation time. The following key is discussed shorten service of basic time, auxiliary time, technology and constituent serve time. Shorten basic time reduces treatment spare parts to there is the following way in the basic time of some working procedure: Shorten pure cutting time, use much knife to undertake machining at the same time to different face. 1.

Use high speed efficient cutting, shorten cutting time should improve cutting efficiency, shorten cutting time, the excision that is about to improve the data inside unit time measures Q, it and cutting 3 element are relative, and the essential factor with the most active, the biggest impact is cutting speed, this is why use high speed cutting to regard as it is important to improve cutting efficiency the reason of the way. In groovy cutting, as the addition of cutting speed, cutting temperature also lifts at the same time, but exceed certain when cutting speed after critical speed (this rate value is followed material differs and be differred by treatment) , cutting temperature follows cutting to rise and rise of speed no longer, can drop instead, because right now majority heat in metal cutting is cut,bits was taken away. Cutting speed and unit cutting force also have similar concern. These mechanism of high speed cutting study achievement provided academic basis for its application, the progress of technology of together with cutting tool, include the development of cutting tool material and cutting tool structure and application, of the machine tool of high firm gender, high power sex, high rotate speed and tall feed speed appear, make the actual application of high speed cutting becomes reality. Graph 3 compound get, boring cutter in addition, powder forgings high-speed steel, exceed fine grain hard alloy, much coating / the wide application of compound coating high-speed steel and hard alloy, al2O3, Si3N4 is the razor blade of pottery and porcelain of matrix, the cermet that is matrix with TiCN and TiC and PCBN, PCD exceed material of strong cutting tool to be used generally of the industry in the car, make the cutting speed of machining of car spare parts and manufacturing efficiency twice rise. If use opening of cylinder of thick boring of razor blade of pottery and porcelain, cutting speed can amount to 800m/min, minutely feed amounts to 2 400mm, aperture of a cylinder needs thick boring only 4s, and if use opening of crock of boring of essence of PCBN razor blade, cutting speed is 750m/min, floor-to-floor time increases greatly. In machining of automobile manufacturing industry, if watch place is shown,high speed cutting applies achieves parameter actually. The research achievement of production economics makes clear, the 3% ～ that cutting tool charge occupies a spare parts to make cost only commonly 5% , but because use the whole that material of advanced cutting tool and place of cutting tool structure bring,manufacture efficiency rise can amount to 20% ～ 30% , because this uses high speed,efficient cutting is to improve productivity most one of economic ways. Of course, the performance data of the machine tool, tigidity and dynamical sex all should get used to the requirement of high speed cutting. Nextpage2.

Use much knife treatment to shorten basic time shortens process is primary another way of time is to use much knife to undertake machining to different face at the same time. Modular machine tool and transfer matic still are the means of a kind of treatment with manufacturing highest efficiency up to now, its used many many knife namely so formerly the reason that has machining at the same time to the many surfaces of the spare parts. Use transfer matic of modular machine tool to machine spare parts of aluminium alloy housing at present, metre can achieve 16s, machine metre of cast-iron housing spare parts to be able to amount to 27s. In crop enough big and product breed is onefold (or little) , below relatively fixed circumstance, transfer matic of modular machine tool is remained acquire efficient optimal option. In addition, still have grinding of much emery wheel, much axis machining center, it is to realize the actor that much knife machines at the same time to choose equipment. Graph the machining center of 5 axes linkage in 4 jobs is in the crankshaft treatment of engine, car - the car is pulled and machine tool of the mill outside high speed reachs cutting tool (see a picture 1, graph 2) the invention gave crankshaft treatment to bring revolutionary progress. The circle outside the main shaft neck that uses machine tool of the one mill outside the stage to be able to machine crankshaft, connecting rod neck, balance piece reachs brace side, introduce car of much bit body - the car pulls a machine tool to be able to machine all main shaft necks or same and phasic connecting rod journal, number improves treatment efficiency and product quality decuply. Shorten auxiliary time before, auxiliary time takes sheet the 70% above of floor-to-floor time, although as all sorts of shortening of auxiliary time method collect what in order to reachs automata technology to rise, those who assist time to still take floor-to-floor time up to now 50% the left and right sides. Shorten the concrete step of auxiliary time basically has: 1.

The machine tool uses workbench of circumgyrate type, reciprocating type, a labour undertake cutting is machined while, another labour undertake the spare parts assembles and unassemble at the same time. 2.

Increase the fast and floating rate of the machine tool and slewing speed. Center of contemporary CNC Machining uses linear electric machinery increasingly, the floating rate of axis of X, Y, Z is in 60m/min above, many equipment already exceeded 100m/min, and acceleration is controlled in 1g commonly, high-grade machining center already was amounted to 1.

5 ～ 2.

0g, taller even. 3.

Use all sorts of change knife handle and implementation of the manipulator that change a knife quickly to change a knife quickly. The wide application that HSK changes knife handle quickly not only the installation precision of the cutting tool in raising high speed to machine, and it cooperates with the fast manipulator that change a knife, can make the time changing a knife of machining center shortens 1 ～ 2s. The parameter in application of high speed cutting 4.

Use knife of machine transfer to other localities, machine to go up to wait for device automatically to the knife, shorten the time moving a knife that changes with blunt cutting tool. 5.

Use compound cutting tool, be like compound the knife that get enlarge, compound get boring cutter of reamer, combination and compound enlarge reamer to wait, make the spare parts holds clip in, many treatment appearance completes in changing a knife or the different treatment content of same treatment surface. The graph has bore, boring and the function that pour wine cup at the same time on 3 shown compound cutting tool, can reduce the frequency that change a knife and time greatly. 6.

Numerical control is compound treatment machine tool is one of way that in recent years the machine tool develops. The development of compound machine tool that different technology and working procedure combine all sorts of much main shaft, much tool carrier is rapid, all sorts of turning centers, grinding center, mill vehicle center and machining center of much axis linkage (see a picture 4) emerge as the times require. A workpiece is installed in a machine tool car, mill can be finished in clip, auger, a variety of craft such as bore with a reamer, tap, grinding and boring, can finish the full treatment content of a workpiece even, reduced next makings on workpiece and the time that hold clip for many times. 7.

Use hydraulic pressure, pneumatic the clamping apparatus of fast clamp, use all sorts of detects automatically quantity instrument in machining a process, shorten outfit clip and measure wait for auxiliary sex time. 8.

Use device of multiform makings of automatic, semi-automatic fluctuation and manipulator. Shorten although technical service and service of technology of constituent serve time and constituent serve time are not generation of the metropolis when producing each part, but its accident also can produce efficiency to produce certain effect to working procedure. This is part-time concern with manufacturing management, shorten this two part-time ways basically have: 1.

Reasonable arrangement cutting tool changes knife time, when choosing cutting tool and affirmatory cutting parameter, the life that should consider to use cutting tool and photograph of decide the time that change a knife suit. Be in the timeline that change a knife as far as possible commonly hand over to the next shift or breathing space, the time changing a knife that makes all cutting tool life and place definite as far as possible identical or those who be it is diploid, can avoid to stop often in process of spare parts treatment so machine change a knife. 2.

Use standard knife handle, use knife of line transfer to other localities as far as possible, reduce the time of machine tool timing when changing a knife with utmost ground. 3.

Provide the device that discharge bits and guard, in making cut bits to emit into the box that cut bits in order, prevent to cut bits and cooling fluid to splatter everywhere. Use large flow refrigeration and strong bit, implementation cooling fluid offers a platoon centrally, the concentration that cut bits is collected. Conclusion raises manufacturing efficiency is technology concept not only to update, also be the promotion that runs a concept. Using advanced cutting tool, machine tool to realize high speed efficient cutting while, use relevant technology and administrative method even, optimize whole treatment process, the approach that uses diversification realizes those who machine efficiency to rise, implementation arrives again to efficient cutting from high speed cutting the ultimate goal of efficient treatment. CNC Milling