Value engineering transforms medium application in the machine tool

Main demand presses the breed of company new product and norms, the slideway of the beam of the of all kinds CNC Milling that needs grinding to machine length of 2 ～ 4m, pillar and lathe bed, treatment precision asks to be: (1) the linearity error of grinding surface is more than 0.

005mm/1000mm. (2) grinding surface surface roughness is Ra=0.

8 ～ 0.

4 μ M. (3) the function of the machine tool and precision are stable, the operation is convenient, on the safe side. 2.

The dragon door type that quality, norms and price have different specifications domestic and internationally is circumjacent slideway grinder product, function and precision index are not same also. Be like homebred quality relatively grinder of slideway of door of the MM52125A of actor dragon, the price at that time is 950 thousand yuan of RMBs about; And by accepted the price of the congener product that for the quality on the world best German WALRICHCOBURG company produces is 1.2 million dollar about. 3.

If the tentative selection of plan orders goods to abroad, its quality and norms can satisfy treatment precision requirement, but because the price is high, time is more pressing also, reason eliminates to regard a choice as plan. Grinder of periphery of slideway of door of afore-mentioned MM52125A dragon, precision of its grinding surface is highest can amount to 0.

005mm/1000mm, exterior surface roughness achieves Ra=0.

4 μ M, machine tool structure is more advanced also, so, can consider to regard a choice as plan (plan 1) . Use a company from some B2160 double housing planer, in its on 5 big foundations, undertake designing transforming making grinding machine of slideway of periphery of dragon door type, can achieve faster result from time; And this machine tool has moved more than 10 years, each are big reach lathe bed infrastructure (cast and concrete foundation) internal stress trend is steady, install the working environment that is helpful for grinding in the workshop considering this equipment again, lesser to machining precision to affect. Accordingly, think to be on the structural foundation of this double housing planer, the design transforms grinder of slideway of periphery of the door that it is dragon, also be plan of an optional choose (plan 2) . 4.

Transform cost to forecast double housing planer to transform grinder of slideway of periphery of the door that it is dragon, need to add a lot of necessary functions, want a design to change one's costume or dress reach add a few component (graph 1) . Add or transform a project to be as follows: (1) the design is made (or buy) advocate wheelhead and perpendicular wheelhead and emery wheel are amended implement. (2) a certain number of component that improve workbench main transfer machinery and its slideway deputy precision. (3) the aircrew of dc of instead of alternating current machine orgnaization of feed of crossbeam upper tool post, use silicon controlled rectifier (KB) electric ark power supply and timing, with realizing wheelhead minim feed is mixed correction emery wheel. (4) the cooling system that adds workpiece and emery wheel. (5) the dustproof and mobile shield that adds slideway of lathe bed, beam. Press this estimation, transform charge to be 150 thousand yuan of RMBs, if consider the real value of B2160 double housing planer again (it is 600 thousand yuan about at that time) , depreciation cost (it is about 19.

80 thousand yuan) , calculate give transformed total cost to be about 55.

20 thousand yuan of RMBs. 2, the function is analysed to realize circumjacent grinding, reach the grinding mass of a requirement, the grinder after transforming must have the following function: 1.

Advocate wheelhead roll is used at grinding advocate planar, use short 3 tile force structure of bearing of circular type dynamic pressure, can make sure precision of main shaft circumgyrate is in 0.

005mm less than. 2.

Perpendicular wheelhead roll is used at grinding side plane, use structure of bearing of high accuracy scroll. 3.

Workbench motion is used at workpiece advocate motion namely move back and forth moves point-blank. B2160 double housing planer has had this function, transform the job to just increase drive the rack that is like drive of transmission gear, shaft coupling, workbench and workbench slideway deputy athletic precision, in order to satisfy the requirement of circumjacent grinding. 4.

Motion taking a knife is used at wheelhead level to go knife, perpendicular to walk along knife and sudden shift, outside retaining function of former double housing planer except intermittence and fast feed among them, should add dc aircrew and silicon controlled rectifier additionally (KB) ark of report of timing power supply, reach minim in order to obtain to take the functional demand of the knife continuously. 5.

Crossbeam motion is used at installation and displace wheelhead, achieve grinding the fixed position precision when different height workpiece. Retain the original function of double housing planer entirely. 6.

The work that workpiece refrigeration uses at eliminating grinding process and emery wheel are calorific, prevent workpiece to produce bigger heat to be out of shape. 7.

Slideway protection is used at protecting lathe bed and crossbeam slideway to be not worn away, in order to make sure the machine tool uses the endurance of precision. Graph 1 for grinder functional analysis system technique diagram. The function that evaluation of nextpage3, function chooses to purchase grinder of slideway of door of homebred MM52125A dragon and proper motion to transform grinder of slideway of MB2160 dragon door is comparative, undertake item-by-item is evaluated (use addition evaluation technique) . 1.

The function is main it is important to spend grading function spending is in order to measures every part overall to satisfying the importance rate that functional place has. Form according to the component such as system of wheelhead, workbench, lathe bed, feed overall functional importance degree, if the watch is shown 1 times,give a mark respectively, total grading is ∑ F=362. 2.

The function satisfies degree of grading to be in watch 1 in, contented to the function of two plan degree had given grading. What need points out is, this is a kind of method that forecast, lv of take an examination is so considerate, do one's best is accurate, it is the premise that principle of applied value engineering undertakes mensurable technology is analysed. Express next 1 medium column already statistic gives ∑ F (MM) , ∑ F (MB) the function satisfies degree of grading, the function satisfies rate computation to be as follows: 4, plan is evaluated 1.

The main function of two kinds of plan that qualitative evaluation technique sees the watch is listed 2 times reachs the comparison of technical economic norms. A few Nextpage is qualitative some main sexes conclude after trade off study: Transform program (plan can be compared with technical index buy program newly (plan 1) reduce somewhat, but, its machine work measure scope to increase, and of charge reduce more apparent. So, below the requirement premise that can satisfy manufacturing technology and treatment precision basically in main function and technical index, use transform plan to be in economically a few more economical (functional value VMB2160 is more than VMM52125A) . 2.

Reference of mensurable evaluation technique expresses the data of 3 rows. The computation of cost reduced rate is formulary: According to plan 2, the result that transforms grinder of slideway of MB2160 dragon door by oneself namely is: Functional value is great, namely 1.

471/ is more than 10 thousand yuan 0.

951/ 10 thousand yuan; And cost reduced rate is older (with plan 1 quite) , its are worth for 41.

9% . 5, the final firm ground of plan case of the other side of value engineering principle is decision-making 3 medium payoff, namely function, charge and cycle, after undertaking be evaluatinged integratedly, the decision chooses company proper motion to transform the program of grinder of slideway of MB2160 dragon door, this plan can obtain better below current condition economic benefits. 6, conclusion uses above decision-making plan, the machine tool is transformed score a success, the beam of CNC Milling of current grinding nicety, pillar and lathe bed set can contented company the craft requirement of steel slideway. Plan is decision-making forecast index and the actual measurement index after transforming mediumly to undertake contrast, see a table 4. Practice makes clear, decision-making medium applying is transformed in bed of large scale computer value engineering analyses a method, it is method of a kind of effective analysis of technical economy rationality, also be equipment transforms decision-making important step. CNC Milling CNC Machining