Summary: Screw extruder optimizes a design is to be in given below craft and manufacturing condition, the basis designs requirement and purpose, choose design variable and build target function, in corresponding tie the condition falls, obtain screw parameter to be like the process of the optimal value such as diameter, pitch and snail chamfer deepness. The article basically elaborates screw extruder main parameter, the theoretical foundation that studies Baconian screw extruder optimizes a design and screw optimize the characteristic of the design, the current situation that optimizes a design to screw undertakes summing up reaching expectation. As polymer treatment shapes one of main facility screw extruder, in polymer treatment industry receives wider and wider application, and also will receive more application in other industry. Indicate the main technique parameter of screw extruder character of service has: Snail is shank diameter, long limits of diameter comparing, rotate speed, pull model of the electromotor power that uses screw, production to change canister of ability, machine heat the center of power and section number, machine is mixed high over all dimension. These parameter are the main basis that measure and chooses extruder, also be the technical parameter that design screw extruder should decide above all. Be in according to polymer the metabolic process of the condition of 3 kinds of physics in screw extruder, the screw of screw extruder normally cent is feed in raw material paragraph, melt paragraph and metric paragraph. Because the geometrical structure of screw is very complex, build extruder of screw of a can comprehensive report to optimize the mathematical model of the design hard so. Even if can build ideal screw extruder to optimize the mathematical model of the design, because influencing factor is complex, design variable is much, it is very difficult also that its seek solution, the functional Duan Jianmo that presses screw so undertakes optimizing designing, relatively accord with actual. The basis of theory of theoretical foundation 1) that screw extruder optimizes the theory of the design and extruder of square conch lever to optimize a design: Machinery optimizes a design to have two important segment or content: It is to build the mathematical model that optimizes a problem; 2 it is the method seeking solution that chooses to optimize a problem. To extruder of screw of 3 paragraphs of type, ordinal course solid carries stock, melt and fuse-element are carried wait for different transportation level, and each paragraphs conveyer manages each are not identical. Accordingly, screw extruder feed in raw material paragraph, melt paragraph with computation paragraph the theoretical foundation that optimizes a design also each are not identical, it is respectively: Go out by Daneier and Maerdi and classics tower heart rub Er and Bai Luoyi try to perfect, build the solid on solid attrition mechanism to carry theory, establish the melt theory that learns physical model foundation to go up in the number such as Maduoke, and the hydrokinetics is academic. 2) optimizes a target: Below the premise that assures crowded quality giving thing, achieve highest productivity or most small-power specific power consumption. 3) designs variable: Program of a design can use the numerical value of a group of basic parameter to express. Among them, need actors or actress chosen independent parameter says to design variable. The design variable of screw is normally: Snail is shank diameter, long diameter comparing, whorl rises horn and screw chamfer to wait greatly. The characteristic that screw extruder optimizes the characteristic screw extruder of the design to optimize a design is a design variable is much, much target and simple goal optimize a design to coexist; Of mathematical model multidimensional gender and nonlinear; A variety of key link in designing variable are measured coexist. Screw extruder optimizes the tie with design adoptable commonly used algorithm to optimize design algorithm to have: Law of tie coordinate rotate, tie is random way way, compound look doctrine, Lagrange is multiplied child law and genetic algorithm. Commonly used screw optimizes the method that screw extruder optimizes a design design method has: Analytic law, diagram method and computer simulation emulate a method. Screw optimizes the common procedure basis of the design to squeeze the appearance that gives a course to build physical model, build mathematical model according to physical model, design software is optimized to write screw to optimize design program related application, input the program the computer and take a value to undertake optimizing computation through changing those who optimize a target, undertake analysis and test and verify through optimizing a result to what the computer outputs, reach screw optimizes the parameter of the design. Extruder of research achievement screw optimizes a design to be able to divide extruder of the screw that it is sheet to optimize design and double screw extruder to optimize a design two kinds big. Of screw of odd screw extruder optimize a design to consider to be in early 1994, liang Jizhao is designing the condition that distributings without speed inside solid a place of strategic importance, allude to screw extruder the mathematical expression of rate of going from place to place undertook correction, elaborated screw to optimize the theoretical foundation of the design, include academic basis, optimize target and design variable to wait. Discussed screw to optimize the characteristic of the design: Design parameter namely much, optimize a target to wait more with tie condition more. Introduced screw to optimize the method of the design, include law of analytic law, diagram method, orthogonal design, statistic to analyse law, CAD law and reliable design method to wait. Arrived 2001, liang Jizhao carries theory to analyse a basis for theory with solid a place of strategic importance, assume: The energy that stock and snail arris flank lift because of attrition action and pressure and wastes is less, but oversight; Width of academic snail arris is less than width of actual snail arris, and oversight snail edge is very wide. With specific yield specific power consumption the smallest to optimize a target, build lever of Duan Luo of screw extruder feed in raw material to optimize design target function, rise horn to be design variable with deepness of chamfer of screw external diameter, snail and whorl, reach lever of Duan Luo of extruder feed in raw material optimizes design model, its pass pair of Φ 65mm and Φ 85mm of screw of two kinds of plastic extruder optimize a result to make clear, the only waste time of screw design program of more original machine reduces the screw after optimizing one times the left and right sides; But because be in,the hypothesis condition in bibliographical reference and actual condition existence contradict certainly, if the groovy form of screw assumes,be rectangle, and actual in it is echelon commonly, the error that makes optimize calculative result to exist certain; But be opposite among them the optimizes design place to do theory of odd screw extruder and the test that carry out device, optimized a design to lay a foundation for farther screw. 2002, liang Jizhao mixes to change mechanism with model according to melt, it is hypothesis condition with model of the Newton in melt theory, to screw melt Duan Jin optimizes a design all right, build screw melt paragraph optimize design maths model. According to mathematical model, the choice restrains complex form doctrine to undertake finding actor, odd to Φ 70mm screw undertakes optimizing designing, can get screw melt paragraph case, edge of arris of deepness of endmost snail chamfer, snail is wide the optimal cost that raises part with screw is 15mm, 4mm, 7mm, 22 ° respectively. Of the same age, the geometrical structure parameter with main lever of metric to screw extruder Duan Luo has technology of computer of Liang Jizhao application optimize a design, below the premise that assumes the stock fluid flow between screw and machine canister is the isothermal stickiness between two flat to flow, derivation gives extruder metric paragraph productivity expression: Among them, η the frit makings viscosity in chamfer of 1 delegate snail, η the frit makings viscosity in F of δ of 2 delegates clearance, can check a watch to obtain. Build mathematical model next, extruder of odd to Φ 65mm screw undertakes optimizing designing, application restrains random direction algorithm to seek solution, beg a deepness of chamfer of metric Duan Luo, snail to carry the clearance between top of snail of width, screw and machine canister and screw on the head to rise optimal value of horn to be: 3mm, 7mm, 0. 35mm, with 30. The research document that screw of double screw extruder optimizes a design is used one dimension, nonlinear optimize algorithm, add up to a gender to optimize a design with type of screw of extruder of Xiang Shuang screw to tine, optimize a target to be: The energy of the smallest temperature rise, lowest is used up, the biggest pressure gradient is built inside the shortest axial distance, undertake test and verify with quality equation, the test that uses a system undertakes examining. Although the research that looks into forefathers to optimize a design to screw extruder obtained a few positive result, but still put in a few problems, remain to study further and be perfected. The research that the author thinks screw extruder will optimize a design henceforth should emphasize the following aspects: 1) .
The design of screw extruder remains theoretically at further research, devising theory is the foundation that optimizes a design, especially the research of function of parameter of screw orgnaization geometry and screw extruder discharge, power and extruding model. 2) .
At present screw optimizes the research of the design to basically be centered in extruder of screw of medium, diminutive, the research achievement that how optimizes extruder of medium, small-sized screw the design applies on large screw extruder, also be the issue that needs attention. 3) .
Target screw optimizes the research of the design to basically be centered in odd screw extruder, the research of double screw extruder is very few, so double screw extruder optimizes the research of the design to remain to strengthen. CNC Milling
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