塑料注塑模具中英文对照外文翻译文献

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注塑模具工艺立体光照成型毕业论文中英文对照资料外文翻译文献

注塑模具工艺中英文对照资料外文翻译文献附录2Integrated simulation of the injection molding process withstereolithography moldsAbstract Functional parts are needed for design veriﬁcation testing, ﬁeld trials, customer evaluation, and production planning. By eliminating multiple steps, the creation of the injection mold directly by a rapid prototyping (RP) process holds the best promise of reducing the time and cost needed to mold low-volume quantities of parts. The potential of this integration of injection molding with RP has been demonstrated many times. What is missing is the fundamental understanding of how the modiﬁcations to the mold material and RP manufacturing process impact both the mold design and the injection molding process. In addition, numerical simulation techniques have now become helpful tools of mold designers and process engineers for traditional injection molding. But all current simulation packages for conventional injection molding are no longer applicable to this new type of injection molds, mainly because the property of the mold material changes greatly. In this paper, an integrated approach to accomplish a numerical simulation of injection molding into rapid-prototyped molds is established and a corresponding simulation system is developed. Comparisons with experimental results are employed for veriﬁcation, which show that the present scheme is well suited to handle RP fabricated stereolithography (SL) molds.Keywords Injection molding Numerical simulation Rapid prototyping1 IntroductionIn injection molding, the polymer melt at high temperature is injected into the mold under high pressure [1]. Thus, the mold material needs to have thermal and mechanical properties capable of withstanding the temperatures and pressures of the molding cycle. The focus of many studies has been to create theinjection mold directly by a rapid prototyping (RP) process. By eliminating multiple steps, this method of tooling holds the best promise of reducing the time and cost needed to createlow-volume quantities of parts in a production material. The potential of integrating injection molding with RP technologies has been demonstrated many times. The properties of RP molds are very different from those of traditional metal molds. The key differences are the properties of thermal conductivity and elastic modulus (rigidity). For example, the polymers used in RP-fabricated stereolithography (SL) molds have a thermal conductivity that is less than one thousandth that of an aluminum tool. In using RP technologies to create molds, the entire mold design and injection-molding process parameters need to be modiﬁed and optimized from traditional methodologies due to the completely different tool material. However, there is still not a fundamental understanding of h ow the modiﬁcations to the mold tooling method and material impact both the mold design and the injection molding process parameters. One cannot obtain reasonable results by simply changing a few material properties in current models. Also, using traditional approaches when making actual parts may be generating sub-optimal results. So there is a dire need to study the interaction between the rapid tooling (RT) process and material and injection molding, so as to establish the mold design criteria and techniques for an RT-oriented injection molding process.In addition, computer simulation is an effective approach for predicting the quality of molded parts. Commercially available simulation packages of the traditional injection molding process have now become routine tools of the mold designer and process engineer [2]. Unfortunately, current simulation programs for conventional injection molding are no longer applicable to RP molds, because of the dramatically dissimilar tool material. For instance, in using the existing simulation software with aluminum and SL molds and comparing with experimental results, though the simulation values of part distortion are reasonable for the aluminum mold, results are unacceptable, with the error exceeding 50%. The distortion during injection molding is due to shrinkage and warpage of the plastic part, as well as the mold. For ordinarily molds, the main factor is the shrinkage and warpage of the plastic part, which is modeled accurately in current simulations. But for RP molds, the distortion of the mold has potentially more inﬂuence, which have been neglected in current models. For instance, [3] used a simple three-step simulation process to consider the mold distortion, which had too much deviation.In this paper, based on the above analysis, a new simulation system for RP molds is developed. The proposed system focuses on predicting part distortion, which is dominating defect in RP-molded parts. The developed simulation can be applied as an evaluation tool for RP mold design and process opti mization. Our simulation system is veriﬁed by an experimental example.Although many materials are available for use in RP technologies, we concentrate on usingstereolithography (SL), the original RP technology, to create polymer molds. The SL process uses photopolymer and laser energy to build a part layer by layer. Using SL takes advantage of both the commercial dominance of SL in the RP industry and the subsequent expertise base that has been developed for creating accurate, high-quality parts. Until recently, SL was primarily used to create physical models for visual inspection and form-ﬁt studies with very limited func-tional applications. However, the newer generation stereolithographic photopolymers have improved dimensional, mechanical and thermal properties making it possible to use them for actual functional molds.2 Integrated simulation of the molding process2.1 MethodologyIn order to simulate the use of an SL mold in the injection molding process, an iterative method is proposed. Different software modules have been developed and used to accomplish this task. The main assumption is that temperature and load boundary conditions cause signiﬁcant distortions in the SL mold. The simulation steps are as follows:1T he part geometry is modeled as a solid model, which is translated to a ﬁle readable by the ﬂow analysis package.2Simulate the mold-ﬁlling process of the melt into a pho topolymer mold, which will output the resulting temperature and pressure proﬁles.3Structural analysis is then performed on the photopolymer mold model using the thermal and load boundary conditions obtained from the previous step, which calculates the distortion that the mold undergo during the injection process.4If the distortion of the mold converges, move to the next step. Otherwise, the distorted mold cavity is then modeled (changes in the dimensions of the cavity after distortion), and returns to the second step to simulate the melt injection into the distorted mold.5The shrinkage and warpage simulation of the injection molded part is then applied, which calculates the ﬁnal distor tions of the molded part.In above simulation ﬂow, there are three basic simulation mod ules.2. 2 Filling simulation of the melt2.2.1 Mathematical modelingIn order to simulate the use of an SL mold in the injection molding process, an iterativemethod is proposed. Different software modules have been developed and used to accomplish this task. The main assumption is that temperature and load boundary conditions cause significant distortions in the SL mold. The simulation steps are as follows:1. The part geometry is modeled as a solid model, which is translated to a file readable by the flow analysis package.2. Simulate the mold-filling process of the melt into a photopolymer mold, which will output the resulting temperature and pressure profiles.3. Structural analysis is then performed on the photopolymer mold model using the thermal and load boundary conditions obtained from the previous step, which calculates the distortion that the mold undergo during the injection process.4. If the distortion of the mold converges, move to the next step. Otherwise, the distorted mold cavity is then modeled (changes in the dimensions of the cavity after distortion), and returns to the second step to simulate the melt injection into the distorted mold.5. The shrinkage and warpage simulation of the injection molded part is then applied, which calculates the final distortions of the molded part.In above simulation flow, there are three basic simulation modules.2.2 Filling simulation of the melt2.2.1 Mathematical modelingComputer simulation techniques have had success in predicting filling behavior in extremely complicated geometries. However, most of the current numerical implementation is based on a hybrid finite-element/finite-difference solution with the middleplane model. The application process of simulation packages based on this model is illustrated in Fig. 2-1. However, unlike the surface/solid model in mold-design CAD systems, the so-called middle-plane (as shown in Fig. 2-1b) is an imaginary arbitrary planar geometry at the middle of the cavity in the gap-wise direction, which should bring about great inconvenience in applications. For example, surface models are commonly used in current RP systems (generally STL file format), so secondary modeling is unavoidable when using simulation packages because the models in the RP and simulation systems are different. Considering these defects, the surface model of the cavity is introduced as datum planes in the simulation, instead of the middle-plane.According to the previous investigations [4–6], fillinggoverning equations for the flow and temperature field can be written as:where x, y are the planar coordinates in the middle-plane, and z is the gap-wise coordinate; u, v,w are the velocity components in the x, y, z directions; u, v are the average whole-gap thicknesses; and η, ρ,CP (T), K(T) represent viscosity, density, specific heat and thermal conductivity of polymer melt, respectively.Fig.2-1 a–d. Schematic procedure of the simulation with middle-plane model. a The 3-D surface model b The middle-plane model c The meshed middle-plane model d The display of the simulation result In addition, boundary conditions in the gap-wise direction can be defined as:where TW is the constant wall temperature (shown in Fig. 2a).Combining Eqs. 1–4 with Eqs. 5–6, it follows that the distributions of the u, v, T, P at z coordinates should be symmetrical, with the mirror axis being z = 0, and consequently the u, v averaged in half-gap thickness is equal to that averaged in wholegap thickness. Based on this characteristic, we can divide the whole cavity into two equal parts in the gap-wise direction, as described by Part I and Part II in Fig. 2b. At the same time, triangular finite elements are generated in the surface(s) of the cavity (at z = 0 in Fig. 2b), instead of the middle-plane (at z = 0 in Fig. 2a). Accordingly, finite-difference increments in the gapwise direction are employed only in the inside of the surface(s) (wall to middle/center-line), which, in Fig. 2b, means from z = 0 to z = b. This is single-sided instead of two-sided with respect to the middle-plane (i.e. from the middle-line to two walls). In addition, the coordinate system is changed from Fig. 2a to Fig. 2b to alter the finite-element/finite-difference scheme, as shown in Fig. 2b. With the above adjustment, governing equations are still Eqs. 1–4. However, the original boundary conditions inthe gapwise direction are rewritten as:Meanwhile, additional boundary conditions must be employed at z = b in order to keep the flows at the juncture of the two parts at the same section coordinate [7]:where subscripts I, II represent the parameters of Part I and Part II, respectively, and Cm-I and Cm-II indicate the moving free melt-fronts of the surfaces of the divided two parts in the filling stage.It should be noted that, unlike conditions Eqs. 7 and 8, ensuring conditions Eqs. 9 and 10 are upheld in numerical implementations becomes more difficult due to the following reasons:1. The surfaces at the same section have been meshed respectively, which leads to a distinctive pattern of finite elements at the same section. Thus, an interpolation operation should be employed for u, v, T, P during the comparison between the two parts at the juncture.2. Because the two parts have respective flow fields with respect to the nodes at point A and point C (as shown in Fig. 2b) at the same section, it is possible to have either both filled or one filled (and one empty). These two cases should be handled separately, averaging the operation for the former, whereas assigning operation for the latter.3. It follows that a small difference between the melt-fronts is permissible. That allowance can be implemented by time allowance control or preferable location allowance control of the melt-front nodes.4. The boundaries of the flow field expand by each melt-front advancement, so it is necessary to check the condition Eq. 10 after each change in the melt-front.5. In view of above-mentioned analysis, the physical parameters at the nodes of the same section should be compared and adjusted, so the information describing finite elements of the same section should be prepared before simulation, that is, the matching operation among the elements should be preformed.Fig. 2a,b. Illustrative of boundary conditions in the gap-wise direction a of the middle-plane model b of thesurface model2.2.2 Numerical implementationPressure field. In modeling viscosity η, which is a function of shear rate, temperature and pressure of melt, the shear-thinning behavior can be well represented by a cross-type model such as:where n corresponds to the power-law index, and τ∗ characterizes the shear stress level of the transition region between the Newtonian and power-law asymptotic limits. In terms of an Arrhenius-type temperature sensitivity and exponential pressure dependence, η0(T, P) can be represented with reasonable accuracy as follows:Equations 11 and 12 constitute a five-constant (n, τ∗, B, Tb, β) representation for viscosity. The shear rate for viscosity calculation is obtained by:Based on the above, we can infer the following filling pressure equation from the governing Eqs. 1–4:where S is calculated by S = b0/(b−z)2η d z. Applying the Galerkin method, the pressure finite-element equation is deduced as:where l_ traverses all elements, including node N, and where I and j represent the local node number in element l_ corresponding to the node number N and N_ in the whole, respectively. The D(l_) ij is calculated as follows:where A(l_) represents triangular finite elements, and L(l_) i is the pressure trial function in finite elements.Temperature field. To determine the temperature profile across the gap, each triangular finite element at the surface is further divided into NZ layers for the finite-difference grid.The left item of the energy equation (Eq. 4) can be expressed as:where TN, j,t represents the temperature of the j layer of node N at time t.The heat conduction item is calculated by:where l traverses all elements, including node N, and i and j represent the local node number in element l corresponding to the node number N and N_ in the whole, respectively.The heat convection item is calculated by:For viscous heat, it follows that:Substituting Eqs. 17–20 into the energy equation (Eq. 4), the temperature equation becomes:2.3 Structural analysis of the moldThe purpose of structural analysis is to predict the deformation occurring in the photopolymer mold due to the thermal and mechanical loads of the filling process. This model is based on a three-dimensional thermoelastic boundary element method (BEM). The BEM is ideally suited for this application because only the deformation of the mold surfaces is of interest. Moreover, the BEM has an advantage over other techniques in that computing effort is not wasted on calculating deformation within the mold.The stresses resulting from the process loads are well within the elastic range of the mold material. Therefore, the mold deformation model is based on a thermoelastic formulation. The thermal and mechanical properties of the mold are assumed to be isotropic and temperature independent.Although the process is cyclic, time-averaged values of temperature and heat flux are used for calculating the mold deformation. Typically, transient temperature variations within a mold have been restricted to regions local to the cavity surface and the nozzle tip [8]. The transients decay sharply with distance from the cavity surface and generally little variation is observed beyond distances as small as 2.5 mm. This suggests that the contribution from the transients to the deformation at the mold block interface is small, and therefore it is reasonable to neglect the transient effects. The steady state temperature field satisfies Laplace’s equation 2T = 0 and the time-averaged boundary conditions. The boundary conditions on the mold surfaces are described in detail by Tang et al. [9]. As for the mechanical boundary conditions, the cavity surface is subjected to the melt pressure, the surfaces of the mold connected to the worktable are fixed in space, and other external surfaces are assumed to be stress free.The derivation of the thermoelastic boundary integral formulation is well known [10]. It is given by:where uk, pk and T are the displacement, traction and temperature,α, ν represent the thermal expansion coefficient and Poisson’s ratio of the material, and r = |y−x|. clk(x) is the surfacecoefficient which depends on the local geometry at x, the orientation of the coordinate frame and Poisson’s ratio for the domain [11]. The fundamental displacement ˜ulk at a point y in the xk direction, in a three-dimensional infinite isotropic elastic domain, results from a unit load concentrated at a point x acting in the xl direction and is of the form:where δlk is the Kronecker delta function and μ is the shear modulus of the mold material.The fundamental traction ˜plk , measured at the point y on a surface with unit normal n, is:Discretizing the surface of the mold into a total of N elements transforms Eq. 22 to:where Γn refers to the n th surface element on the domain.Substituting the appropriate linear shape functions into Eq. 25, the linear boundary element formulation for the mold deformation model is obtained. The equation is applied at each node on the discretized mold surface, thus giving a system of 3N linear equations, where N is the total number of nodes. Each node has eight associated quantities: three components of displacement, three components of traction, a temperature and a heat flux. The steady state thermal model supplies temperature and flux values as known quantities for each node, and of the remaining six quantities, three must be specified. Moreover, the displacement values specified at a certain number of nodes must eliminate the possibility of a rigid-body motion or rigid-body rotation to ensure a non-singular system of equations. The resulting system of equations is assembled into a integrated matrix, which is solved with an iterative solver.2.4 Shrinkage and warpage simulation of the molded partInternal stresses in injection-molded components are the principal cause of shrinkage and warpage. These residual stresses are mainly frozen-in thermal stresses due to inhomogeneous cooling, when surface layers stiffen sooner than the core region, as in free quenching. Based onthe assumption of the linear thermo-elastic and linear thermo-viscoelastic compressible behavior of the polymeric materials, shrinkage and warpage are obtained implicitly using displacement formulations, and the governing equations can be solved numerically using a finite element method.With the basic assumptions of injection molding [12], the components of stress and strain are given by:The deviatoric components of stress and strain, respectively, are given byUsing a similar approach developed by Lee and Rogers [13] for predicting the residual stresses in the tempering of glass, an integral form of the viscoelastic constitutive relationships is used, and the in-plane stresses can be related to the strains by the following equation:Where G1 is the relaxation shear modulus of the material. The dilatational stresses can be related to the strain as follows:Where K is the relaxation bulk modulus of the material, and the definition of α and Θ is:If α(t) = α0, applying Eq. 27 to Eq. 29 results in:Similarly, applying Eq. 31 to Eq. 28 and eliminating strain εxx(z, t) results in:Employing a Laplace transform to Eq. 32, the auxiliary modulus R(ξ) is given by:Using the above constitutive equation (Eq. 33) and simplified forms of the stresses and strains in the mold, the formulation of the residual stress of the injection molded part during the cooling stage is obtain by:Equation 34 can be solved through the application of trapezoidal quadrature. Due to the rapid initial change in the material time, a quasi-numerical procedure is employed for evaluating the integral item. The auxiliary modulus is evaluated numerically by the trapezoidal rule.For warpage analysis, nodal displacements and curvatures for shell elements are expressed as:where [k] is the element stiffness matrix, [Be] is the derivative operator matrix, {d} is the displacements, and {re} is the element load vector which can be evaluated by:The use of a full three-dimensional FEM analysis can achieve accurate warpage results, however, it is cumbersome when the shape of the part is very complicated. In this paper, a twodimensional FEM method, based on shell theory, was used because most injection-molded parts have a sheet-like geometry in which the thickness is much smaller than the other dimensions of the part. Therefore, the part can be regarded as an assembly of flat elements to predict warpage. Each three-node shell element is a combination of a constant strain triangular element (CST) and a discrete Kirchhoff triangular element (DKT), as shown in Fig. 3. Thus, the warpage can be separated into plane-stretching deformation of the CST and plate-bending deformation of the DKT, and correspondingly, the element stiffness matrix to describe warpage can also be divided into the stretching-stiffness matrix and bending-stiffness matrix.Fig. 3a–c. Deformation decomposition of shell element in the local coordinate system. a In-plane stretchingelement b Plate-bending element c Shell element3 Experimental validationTo assess the usefulness of the proposed model and developed program, verification is important. The distortions obtained from the simulation model are compared to the ones from SL injection molding experiments whose data is presented in the literature [8]. A common injection molded part with the dimensions of 36×36×6 mm is considered in the experiment, as shown in Fig. 4. The thickness dimensions of the thin walls and rib are both 1.5 mm; and polypropylene was used as the injection material. The injection machine was a production level ARGURY Hydronica 320-210-750 with the following process parameters: a melt temperature of 250 ◦C; an ambient temperature of 30 ◦C; an injection pressure of 13.79 MPa; an injection time of 3 s; and a cooling time of 48 s. The SL material used, Dupont SOMOSTM 6110 resin, has the ability to resist temperatures of up to 300 ◦C temperatures. As mentioned above, thermal conductivity of the mold is a major factor that differentiates between an SL and a traditional mold. Poor heat transfer in the mold would produce a non-uniform temperature distribution, thus causing warpage that distorts the completed parts. For an SL mold, a longer cycle time would be expected. The method of using a thin shell SL mold backed with a higher thermal conductivity metal (aluminum) was selected to increase thermal conductivity of the SL mold.Fig. 4. Experimental cavity modelFig. 5. A comparison of the distortion variation in the X direction for different thermal conductivity; where “Experimental”, “present”, “three-step”, and “conventional” mean the results of the experimental, the presented simulation, the three-step simulation process and the conventional injection molding simulation, respectively.Fig. 6. Comparison of the distortion variation in the Y direction for different thermal conductivitiesFig. 7. Comparison of the distortion variation in the Z direction for different thermal conductivitiesFig. 8. Comparison of the twist variation for different thermal conductivities For this part, distortion includes the displacements in three directions and the twist (the difference in angle between two initially parallel edges). The validation results are shown in Fig.5 to Fig. 8. These figures also include the distortion values predicted by conventional injection molding simulation and the three-step model reported in [3].4 ConclusionsIn this paper, an integrated model to accomplish the numerical simulation of injection molding into rapid-prototyped molds is established and a corresponding simulation system is developed. For verification, an experiment is also carried out with an RPfabricated SL mold.It is seen that a conventional simulation using current injection molding software breaks down for a photopolymer mold. It is assumed that this is due to the distortion in the mold caused by the temperature and load conditions of injection. The three-step approach also has much deviation. The developed model gives results closer to experimental.Improvement in thermal conductivity of the photopolymer significantly increases part quality. Since the effect of temperature seems to be more dominant than that of pressure (load), an improvement in the thermal conductivity of the photopolymer can improve the part quality significantly.Rapid Prototyping (RP) is a technology makes it possible to manufacture prototypes quickly and inexpensively, regardless of their comp lexity. Rapid Tooling (RT) is the next step in RP’s steady progress and much work is being done to obtain more accurate tools to define the parameters of the process. Existing simulation tools can not provide the researcher with a useful means of studying relative changes. An integrated model, such as the one presented in this paper, is necessary to obtain accurate predictions of the actual quality of final parts. In the future, we expect to see this work expanded to develop simulations program for injection into RP molds manufactured by other RT processes.References1. Wang KK (1980) System approach to injection molding process. Polym-Plast Technol Eng 14(1):75–93.2. Shelesh-Nezhad K, Siores E (1997) Intelligent system for plastic injection molding process design. J Mater Process Technol 63(1–3):458–462.3. Aluru R, Keefe M, Advani S (2001) Simulation of injection molding into rapid-prototyped molds. Rapid Prototyping J 7(1):42–51.4. Shen SF (1984) Simulation of polymeric flows in the injection molding process. Int J Numer Methods Fluids 4(2):171–184.5. Agassant JF, Alles H, Philipon S, Vincent M (1988) Experimental and theoretical study of the injection molding of thermoplastic materials. Polym Eng Sci 28(7):460–468.6. Chiang HH, Hieber CA, Wang KK (1991) A unified simulation of the filling and post-filling stages in injection molding. Part I: formulation. Polym Eng Sci 31(2):116–124.7. Zhou H, Li D (2001) A numerical simulation of the filling stage in injection molding based on a surface model. Adv Polym Technol 20(2):125–131.8. Himasekhar K, Lottey J, Wang KK (1992) CAE of mold cooling in injection molding using a three-dimensional numerical simulation. J EngInd Trans ASME 114(2):213–221.9. Tang LQ, Pochiraju K, Chassapis C, Manoochehri S (1998) Computeraided optimization approach for the design of injection mold cooling systems. J Mech Des, Trans ASME 120(2):165–174.10. Rizzo FJ, Shippy DJ (1977) An advanced boundary integral equation method for three-dimensional thermoelasticity. Int J Numer Methods Eng 11:1753–1768.11. Hartmann F (1980) Computing the C-matrix in non-smooth boundary points. In: New developments in boundary element methods, CML Publications, Southampton, pp 367–379.12. Chen X, Lama YC, Li DQ (2000) Analysis of thermal residual stress in plastic injection molding. J Mater Process Technol 101(1):275–280.13. Lee EH, Rogers TG (1960) Solution of viscoelastic stress analysis problems using measured creep or relaxation function. J Appl Mech 30(1):127–134.14. Li Y (1997) Studies in direct tooling using stereolithography. Dissertation, University of Delaware, Newark, DE..。

注塑模部分中英文对照

注塑模部分中英文对照塑料成形模具mould for plastics热塑性塑料模mould for thermoplastics热固性塑料模mould for thermosets压缩模compression mould压注模、传递模transfer mould注射模injection mould热塑性塑料注射模injection mould for thermoplastics热固性塑料注射模injection mould for thermoses成形零件定模stationary mould fixed half动模movable mould moving half定模座板fixed clamp plate, top clamping plate. top plate动模座板moving clamp plate. bottom clamping plate. bottom plate 上模座板upper clamping plate下模座板lower clamping plate凹模固定板cavity-retainer plate型芯固定板core-retainer plate凸模固定板punch-retainer plate模套chase. bolster. frame支承板backing plate. supprr plate垫块spacer parallel支架ejector housing. mould base leg动模movable mould moving half定模座板fixed clamp plate, top clamping plate. top plate动模座板moving clamp plate. bottom clamping plate. bottom plate 上模座板upper clamping plate下模座板lower clamping plate凹模固定板cavity-retainer plate型芯固定板core-retainer plate凸模固定板punch-retainer plate模套chase. bolster. frame垫块spacer parallel支架ejector housing. mould base leg压力铸造模具die-casting die压铸模零部件定模fixed die, cover die定模座板fixed clamping plate定模套板bolstor, fixed die动模moving die,ejector die动模座板moving clamping plate 直流道sprue横流道runner内浇口gate。

塑料注塑模具并行设计外文翻译、中英文翻译、外文文献翻译

塑料注塑模具并行设计Assist.Prof.Dr. A. YAYLA /Prof.Dr. Paş a YAYLA摘要塑料制品制造业近年迅速成长。

其中最受欢迎的制作过程是注塑塑料零件。

注塑模具的设计对产品质量和效率的产品加工非常重要。

模具公司想保持竞争优势,就必须缩短模具设计和制造的周期。

模具是工业的一个重要支持行业，在产品开发过程中作为一个重要产品设计师和制造商之间的联系。

产品开发经历了从传统的串行开发设计制造到有组织的并行设计和制造过程中,被认为是在非常早期的阶段的设计。

并行工程的概念(CE)不再是新的,但它仍然是适用于当今的相关环境。

团队合作精神、管理参与、总体设计过程和整合IT工具仍然是并行工程的本质。

CE过程的应用设计的注射过程包括同时考虑塑件设计、模具设计和注塑成型机的选择、生产调度和成本中尽快设计阶段。

介绍了注射模具的基本结构设计。

在该系统的基础上,模具设计公司分析注塑模具设计过程。

该注射模设计系统包括模具设计过程及模具知识管理。

最后的原则概述了塑料注射模并行工程过程并对其原理应用到设计。

关键词:塑料注射模设计、并行工程、计算机辅助工程、成型条件、塑料注塑、流动模拟1、简介注塑模具总是昂贵的,不幸的是没有模具就不可能生产模具制品。

每一个模具制造商都有他/她自己的方法来设计模具,有许多不同的设计与建造模具。

当然最关键的参数之一,要考虑到模具设计阶段是大量的计算、注射的方法,浇注的的方法、研究注射成型机容量和特点。

模具的成本、模具的质量和制件质量是分不开的在针对今天的计算机辅助充型模拟软件包能准确地预测任何部分充填模式环境中。

这允许快速模拟实习,帮助找到模具的最佳位置。

工程师可以在电脑上执行成型试验前完成零件设计。

工程师可以预测过程系统设计和加工窗口,并能获得信息累积所带来的影响,如部分过程变量影响性能、成本、外观等。

2、注射成型法注塑成型是最有效的方法之一,将塑料最好的一面呈现。

这是普遍用于制造复杂的制件,优点是简单、经济、准确与少浪费。

注塑成型过程外文文献翻译、中英文翻译

附录 1：外文翻译介绍如今塑料在日常生活中占据着极其重要的地位。

如果我们说，没有哪个领域的塑料没有不经过制造中直接到宇宙飞船的生产中，这一点也不夸张。

在19 世纪中叶，塑料开始在材料和生活中起主导作用。

耐腐蚀性是塑料甚至成为金属和提高制造生产率方面受到了很高的关注。

从塑料的紧缺，因此在塑料产品设计等各个方面发生巨大的变革,在制造加工领域还在测试阶段,现在,由于很多人最后通过体力劳动取得了卓越的成效,另外人工智能的帮助下,开发出了CAD / CAM 软件。

由于高强度的重量比，提高了化学稳定性和耐温性，具有耐热和耐腐蚀的特性，光泽性使其成为材料更好的选择。

塑料在形成过程中消耗的能量更少，并且可以被循环利用。

今天，塑料正在取代黄铜、铜、铸铁、钢铁等金属。

塑料可以根据制造方法分类，在加热时软化，在冷却时凝固。

这些被称为“热塑性塑料”，以及那些由于化学变化而变硬的物质。

这些被称为热固性或混合型塑料材料成为产品选择特殊材料是另一个重要因素。

这对于产品的确定是非常必要的。

它也应该能够承受压力。

每种材料都有自己的属性。

一些材料在高环境和耐磨性方面比较好。

困难的是找到一种合适材料，它将完全满足整个要求。

所以材料应该是通用的，它适合我们产品的所有考虑条件和要求。

在考虑了所有这些点的材料之后，必须选择合适的材料来满足所有这些条件。

注塑成型过程它是一种通过将熔融状态的物质注入模具来生产零件的生产工艺。

注射成型被用在很多领域进行生产，包括金属、眼镜、弹性体、糖果以及最常见的热塑性塑料和热固性塑料。

将材料的一部分送入一个加热的桶，混合，并用高压压入一个模腔，它是可以冷却和硬化地方。

在产品设计后，通常由工业设计师或工程师设计模具，模具由模具制造商(或工具制造商)制造，通常由金属或铝制成，并经过精密加工以形成所需的特性。

注塑成型广泛应用于制造各种零件，从最小的零件到汽车的整个车身。

零件的形状和特点、模具的所需材料，以及造型机的性能都必须考虑在内。

塑料注射成型外文文献翻译、中英文翻译、外文翻译

塑料注射成型外文文献翻译、中英文翻译、外文翻译外文翻译原文：Injection MoldingMany different processes are used to transform plastic granules, powders, and liquids into product. The plastic material is in moldable form, and is adaptable to various forming methods. In most cases thermosetting materials require other methods of forming. This is recognized by the fact that thermoplastics are usually heated to a soft state and then reshaped before cooling. Theromosets, on the other hand have not yet been polymerized before processing, and the chemical reaction takes place during the process, usually through heat, a catalyst, or pressure. It is important to remember this concept while studying the plastics manufacturing processes and polymers used.Injection molding is by far the most widely used process of forming thermoplastic materials. It is also one of the oldest. Currently injection molding accounts for 30% of all plastics resin consumption. Since raw material can be converted by a single procedure, injection molding is suitable for mass production of plastics articles and automated one-step production of complex geometries. In most cases, finishing is not necessary. Typical products include toys, automotive parts, household articles, and consumer electronics goods.Since injection molding has a number of interdependent variables, it is a process of considerable complexity. The success of the injection molding operation is dependent not only in the proper setup of the machine hydraulics, barrel temperaturevariations, and changes in material viscosity. Increasing shot-to-shot repeatability of machine variables helps produce parts with tighter tolerance, lowers the level of rejects, and increases product quality (i.e., appearance and serviceability).The principal objective of any molding operation is the manufacture of products: to a specific quality level, in the shortest time, and using repeatable and fully automaticcycle. Molders strive to reduce or eliminate rejected parts in molding production. For injection molding of high precision optical parts, or parts with a high added value such as appliance cases, the payoff of reduced rejects is high.A typical injection molding cycle or sequence consists of five phases;1. Injection or mold filling2. Packing or compression3. Holding4. Cooling5. Part ejectionPlastic granules are fed into the hopper and through an in the injection cylinder where they are carried forward by the rotating screw. The rotation of the screw forces the granules under high pressure against the heated walls of the cylinder causing them to melt. As the pressure building up, the rotating screw is forced backward until enough plastic has accumulated to make the shot. The injection ram (or screw) forces molten plastic from the barrel, through the nozzle, sprue and runner system, and finally into the mold cavities. During injection, the mold cavity is filled volumetrically. When the plastic contacts the cold mold surfaces, it solidifies (freezes) rapidly to produce theskin layer. Since the core remains in the molten state, plastic follows through the core to complete mold filling. Typically, the cavity is filled to 95%~98% during injection. Then the molding process is switched over to the packing phase.Even as the cavity is filled, the molten plastic begins to cool. Since the cooling plastic contracts or shrinks, it gives rise to defects such as sink marks, voids, and dimensional instabilities. To compensate for shrinkage, addition plastic is forced into the cavity. Once the cavity is packed, pressure applied to the melt prevents molten plastic inside the cavity from back flowing out through the gate. The pressure must be applied until the gate solidifies. The process can be divided into two steps (packing and holding) or may be encompassed in one step(holding or second stage). During packing, melt forced into the cavity by the packing pressure compensates for shrinkage. With holding, the pressure merely prevents back flow of the polymer malt.After the holding stage is completed, the cooling phase starts. During, the part is held in the mold for specified period. The duration of the cooling phase depends primarily on the material properties and the part thickness. Typically, the part temperature must cool below the material’s ejection temperature. While cooling the part, the machine plasticates melt for the next cycle.The polymer is subjected to shearing action as well as the condition of the energy from the heater bands. Once the short is made, plastication ceases. This should occur immediately before the end of the cooling phase. Then the mold opens and the part is ejected.When polymers are fabricated into useful articles they are referred to as plastics, rubbers, and fibers. Some polymers, forexample, cotton and wool, occur naturally, but the great majority of commercial products are synthetic in origin. A list of the names of the better known materials would include Bakelite, Dacron, Nylon, Celanese, Orlon, and Styron.Previous to 1930 the use of synthetic polymers was not widespread. However, they should not be classified as new materials for many of them were known in the latter half of the nineteenth century. The failure to develop them during this period was due, in part, to a lack of understanding of their properties, in particular, the problem of the structure of polymers was the subject of much fruitless controversy.Two events of the twentieth century catapulted polymers into a position of worldwide importance. The first of these was the successful commercial production of the plastic now known as Bakelite. Its industrial usefulness was demonstrated in1912 and in the next succeeding years. T oday Bakelite is high on the list of important synthetic products. Before 1912 materials made from cellulose were available, but their manufacture never provided the incentive for new work in the polymer field such as occurred after the advent of Bakelite. The second event was concerned with fundamental studies of the nature polymers by Staudinger in Europe and by Carohers, who worked with the Du Pont company in Delaware. A greater part of the studies were made during the 1920’s. Staudinger’s work was primarily fundamental. Carother’s achievements led t o the development of our present huge plastics industry by causing an awakening of interest in polymer chemistry, an interest which is still strongly apparent today.The Nature of ThermodynamicsThermodynamics is one of the most important areas ofengineering science used to explain how most things work, why some things do not the way that they were intended, and why others things just cannot possibly work at all. It is a key part of the science engineers use to design automotive engines, heat pumps, rocket motors, power stations, gas turbines, air conditioners, super-conducting transmission lines, solar heating systems, etc.Thermodynamics centers about the notions of energy, the idea that energy is conserved is the first low of thermodynamics. It is starting point for the science of thermodynamics is entropy; entropy provides a means for determining if a process is possible.This idea is the basis for the second low of thermodynamics. It also provides the basis for an engineering analysis in which one calculates the maximum amount of useful that can be obtained from a given energy source, or the minimum amount of power input required to do a certain task.A clear understanding of the ideas of entropy is essential for one who needs to use thermodynamics in engineering analysis. Scientists are interested in using thermodynamics to predict and relate the properties of matter; engineers are interested in using this data, together with the basic ideas of energy conservation and entropy production, to analyze the behavior of complex technological systems.There is an example of the sort of system of interest to engineers, a large central power stations. In this particular plant the energy source is petroleum in one of several forms, or sometimes natural gas, and the plant is to convert as much of this energy as possible to electric energy and to send this energy down the transmission line.Simply expressed, the plant does this by boiling water andusing the steam to turn a turbine which turns an electric generator.The simplest such power plants are able to convert only about 25 percent of the fuel energy to electric energy. But this particular plant converts approximately 40 percent;it has been ingeniously designed through careful application of the basic principles of thermodynamics to the hundreds of components in the system.The design engineers who made these calculations used data on the properties of steam developed by physical chemists who in turn used experimental measurements in concert with thermodynamics theory to develop the property data.Plants presently being studied could convert as much as 55 percent of the fuel energy to electric energy, if they indeed perform as predicted by thermodynamics analysis.The rule that the spontaneous flow of heat is always from hotter to cooler objects is a new physical idea. There is noting in the energy conservation principle or in any other law of nature that specifies for us the direction of heat flow. If energy were to flow spontaneously from a block of ice to a surrounding volume of water, this could occur in complete accord with energy conservation. But such a process never happens. This idea is the substance of the second law of thermodynamics.Clear, a refrigerator, which is a physical system used in kitchen refrigerators, freezers, and air-conditioning units must obey not only the first law (energy conservation) but the second law as well.To see why the second law is not violated by a refrigerator, we must be careful in our statement of law. The second law of thermodynamics says, in effect, that heat never flowsspontaneously from a cooler to a hotter object.Or, alternatively, heat can flow from a cooler to a hotter object only as a result of work done by an external agency. We now see the distinction between an everyday spontaneous process, such as the flow of heat from the inside to the outside of a refrigerator.In the water-ice system, the exchange of energy takes place spontaneously and the flow of heat always proceeds from the water to the ice. The water gives up energy and becomes cooler while the ice receives energy and melts.In a refrigerator, on the other hand, the exchange of energy is not spontaneous. Work provided by an external agency is necessary to reverse the natural flow of heat and cool the interior at the expense of further heating the warmer surroundings.译文：塑料注射成型许多不同的加工过程习惯于把塑料颗粒、粉末和液体转化成最终产品。

塑料模具毕业设计中英文对照资料外文翻译文献

中英文对照资料外文翻译文献一个描述电铸镍壳在注塑模具的应用的技术研究摘要：在过去几年中快速成型技术及快速模具已被广泛开发利用. 在本文中,使用电芯作为核心程序对塑料注射模具分析. 通过差分系统快速成型制造外壳模型. 主要目的是分析电铸镍壳力学特征、研究相关金相组织,硬度,内部压力等不同方面，由这些特征参数以生产电铸设备的外壳. 最后一个核心是检验注塑模具.关键词：电镀；电铸；微观结构；镍1. 引言现代工业遇到很大的挑战，其中最重要的是怎么样提供更好的产品给消费者,更多种类和更新换代问题. 因此,现代工业必定产生更多的竞争性. 毫无疑问,结合时间变量和质量变量并不容易,因为他们经常彼此互为条件; 先进的生产系统将允许该组合以更加有效可行的方式进行，例如,如果是观测注塑系统的转变、我们得出的结论是,事实上一个新产品在市场上具有较好的质量它需要越来越少的时间快速模具制造技术是在这一领域, 中可以改善设计和制造注入部分的技术进步. 快速模具制造技术基本上是一个中小型系列的收集程序，在很短的时间内在可接受的精度水平基础上让我们获得模具的塑料部件。

其应用不仅在更加广阔而且生产也不断增多。

本文包括了很广泛的研究路线,在这些研究路线中我们可以尝试去学习，定义，分析，测试，提出在工业水平方面的可行性，从核心的注塑模具制造获取电铸镍壳，同时作为一个初始模型的原型在一个FDM设备上的快速成型。

不得不说的是,先进的电铸技术应用在无数的行业，但这一研究工作调查到什么程度,并根据这些参数,使用这种技术生产快速模具在技术上是可行的. 都产生一个准确的，系统化使用的方法以及建议的工作方法.2 制造过程的注塑模具薄镍外壳的核心是电铸,获得一个充满epoxic金属树脂的一体化的核心板块模具(图1)允许直接制造注射型多用标本，因为它们确定了新英格兰大学英文国际表卓华组织3167标准。

这样做的目的是确定力学性能的材料收集代表行业。

该阶段取得的核心[4]，根据这一方法研究了这项工作,有如下:a,用CAD系统设计的理想对象b模型制造的快速成型设备(频分多路系统). 所用材料将是一个ABS塑料c一个制造的电铸镍壳，已事先涂有导电涂料(必须有导电).d无外壳模型e核心的生产是背面外壳环氧树脂的抗高温与具有制冷的铜管管道.有两个腔的注塑模具、其中一个是电核心和其他直接加工的移动版. 因此,在同一工艺条件下，同时注入两个标准技术制造，获得相同的工作。

模具塑料注射成型外文翻译外文文献英文文献

模具塑料注射成型外文翻译外文文献英文文献XXXThere are many different processing methods used to convert plastic pellets。

powders。

and liquids into final products。

Plastic materials XXX。

thermoplastic materials XXX。

XXX require other methods。

It is XXX.XXX。

It is also the oldest method。

Suddenly。

XXX account for 30% of all XXX suitable for mass n。

when raw materials XXX in a single step of n。

In most cases。

n machiningis not required for such products。

The us products produced include toys。

automotive parts。

household items。

and electronic consumer goods.Because plastic n molds have many variable nships。

it is a complex and us processing process。

The success of XXX appropriate steps。

but on the XXX。

which leads to the n of XXX。

barrel temperature changes。

XXX ns can help ce tolerances。

ce defect rates。

and increase product quality.XXX operator is to produce products that e first-rate products in the shortest time。

模具外文翻译外文文献英文文献注塑模

模具外文翻译外文文献英文文献注塑模The Injection Molding1、The injection moldingInjection molding is principally used for the production of the thermoplastic parts,although some progress has been made in developing a method for injection molding some thermosetting materials.The problem of injection a method plastic into a mold cavity from a reservoir of melted material has been extremely difficult to solve for thermosetting plastic which cure and harden under such conditions within a few minutes.The principle of injection molding is quite similar to that of die-casting.The process consists of feeding a plastic compound in powered or granular form from a hopper through metering and melting stages and then injecting it into a mold.After a brief cooling period,the mold is opened and the solidified part ejected.Injection-molding machine operation.The advantage of injection molding are：（ⅰ）a high molding speed adapter for mass production is possible；（ⅱ）there is a wide choice of thermoplastic materials providing a variety of useful properties；（ⅲ）it is possible to mold threads,undercuts,side holes,and large thin section.2、The injection-molding machineSeveral methods are used to force or inject the melted plastic into the mold.The most commonly used system in the larger machines is the in-line reciprocating screw,as shown in Figure 2-1.The screw acts as a combination injection and plasticizing unit.As the plastic is fed to the rotating screw,it passes through three zones as shown：feed,compression,and metering.After the feed zone,the screw-flight depth is gradually reduced,force theplastic to compress.The work is converted to heat by conduction from the barrel surface.As the chamber in front of the screw becomes filled,it forces the screw back,tripping a limit switch that activates a hydraulic cylinder that forces the screw forward and injects the fluid plastic into the closed mold.An antiflowback valve presents plastic under pressure from escaping back into the screw flight.The clamping force that a machine is capable of exerting is part of the size designation and is measured in tons.A rule-of-thumb can be used to determine the tonnage required for a particular job.It is based on two tons of clamp force per square inch of projected area.If the flow pattern is difficult and the parts are thin,this may have to go to three or four tons.Many reciprocating-screw machines are capable of handing thermosetting plastic materials.Previously these materials were handled by compression or transfer molding.Thermosetting materials cure or polymerize in the mold and are ejected hot in the range of 375°C～410°C.T hermosetting parts must be allowed to cool in the mold in order or remove them without distortion. Thus thermosetting cycles can be faster.Of course the mold must be heated rather than chilled,as with thermoplastics.3、Basic Underfeed MouldA simple mould of this type is shown in Figure3-1,and the description of the design and the opening sequence follows.The mould consists of three basic parts,namely：the moving half,the floating cavity plate and the feed plate respectively.The moving half consists of The moving mould plate assembly,support block,backing plate,ejector assembly and the pin ejection system.Thus the moving half in this design is identical with the moving half of basic moulds.The floating cavity plate,which may be of the integer or insert-bolster design,is located on substantial guide pillars（not shown）fitted in the feed plate.These guide pillars must be of sufficient length to support the floating cavity plate over its full movement and still project to perform the function of alignment between the cavity and core when the mould is being closed.Guide bushes are fitted into the moving mould plate and the floating cavity plate respectively.The maximum movement of the floating cavity plate is controlled by stop or similar device.The moving mould plate is suitably bored to provide a clearance for the stop bolt assembly.The stop bolts must be long enough to provide sufficient space between the feed plate and the floating cavity plate for easy removal of the feed system.The minimum space provide for should be 65mm just sufficient for an operator to remove the feed system by hand if necessary.The desire operating sequence is for the first daylight to occur between the floating cavity plate.This ensures the sprue is pulled from the sprue bush immediately the mouldis opened.T o achieve this sequence,springs may be incorporated between the feed plate and the floating cavity plate.The springs should be strong enough to give an initial impetus to the floating cavity plate to ensure it moves away with the moving half.It is normal practice to mount the springs on the guide pillars（Figure3-2）and accommodate them in suitable pocket in the cavity plate.The major part of the feed system（runner and sprue）is accommodated in the feed plate to facilitate automatic operation,the runner should be of a trapezoidal form so that once it is pulled from the feed plate is can easily beextracted.Note that if a round runner is used,half the runner is formed in the floating cavity plate,where it would remain,and be prevented from falling or being wiped clear when the mould is opened.Now that we have considered the mould assembly in the some detail,we look at the cycle of operation for this type of mould.The impressions are filled via the feed system（Figure3-1（a））and after a suitable dwell period,the machine platens commence to open.A force is immediately exerted by the compression springs,which cause the floating cavity plate to move away with the moving half as previously discussed.The sprue is pulled from the sprue bush by the sprue puller.After the floating cavity plate has moved a predetermined distance,it is arrested by the stop bolts.The moving half continues to move back and the moldings,having shrunk on to the cores,are withdrawn from the cavities.The pin gate breaks at its junction with the runner（Figure3-1（b））.The sprue puller,being attached to the moving half,is pulled through the floating cavity plate and thereby release the feed system which is then free to fall between the floating cavity plate and the feed plate.The moving half continues to move back until the ejector system is operated and the moldings are ejected （Figure3-1（c））.When the mould is closed,the respective plates are returned to their molding position and the cycle is repeated.4、Feed SystemIt is necessary to provide a flow-way in the injection mould to connect the nozzle（of the injection machine）to each impression.This flow-way is termed the feed system.Normally thefeed system comprises a sprue,runner and gate.These terms applyequally to the flow-way itself,and to the molded material which is remove from the flow-way itself in the process of extracted the molding.A typical feed system for a four-impression,two plate-type mould is shown in Figure4-1.It is seen that the material passes through the sprue,main runner,branch runner and gate before entering the impression.As the temperature of molten plastic is lowered which going through the sprue and runner,the viscosity will rise;however,the viscosity is lowered by shear heat generated when going through the gate to fill the cavity.It is desirable to keep the distance that the material has to travel down to a minimum to reduce pressure and heat losses.It is for this reason that careful consideration must be given to the impression layout gate’s design.4.1.SprueA sprue is a channel through which to transfer molten plastic injected from the nozzle of the injector into the mold.It is a part of sprue bush,which is a separate part from the mold.4.2.RunnerA runner is a channel that guides molten plastic into the cavity of a mold.4.3.GateA gate is an entrance through which molten plastic enters the cavity.The gate has the following function：restricts the flow and the direction of molten plastic；simplifies cutting of a runner and moldings to simplify finishing of parts；quickly cools and solidifies to avoid backflow after molten plastic has filled up in the cavity.4.4.Cold slug wellThe purpose of the cold slug well,shown opposite the sprue,is theoretically to receive the material that has chilled at the front of nozzle during the cooling and ejection phase.Perhaps of greater importance is the fact that it provides position means whereby the sprue bush for ejection purposes.The sprue,the runner and the gate will be discarded after a part is complete.However,the runner and the gate are important items that affect the quality or the cost of parts.5、EjectionA molding is formed in mould by injecting a plastic melt,under pressure,into animpression via a feed system.It must therefore be removed manually.Furthermore,all thermoplastic materials contract as they solidify,which means that the molding will shrink on to the core which forms it.This shrinkage makes the molding difficult to remove. Facilities are provided on the injection machine for automatic actuation of an ejector system,and this is situated behind the moving platen.Because of this,the mould’s ejector system will be most effectively operated if placed in the moving half of the mould,i.e. the half attached to the moving platen.We have stated previously that we need to eject the molding from the core and it therefore follows that the core,too,will most satisfactorily be located in the moving half.The ejector system in a mould will be discussed under three headings,namely：（ⅰ）the ejector grid;（ⅱ）the ejector plate assembly; and（ⅲ）the method of ejection.5.1、Ejector gridThe ejector grid（Figure5-1）is that part of the mould which supports the mould plate and provides a space into which theejector plate assembly can be fitted and operated.The grid normally consists of a back plate on to which is mounted a number of conveniently shaped “support blocks”.The ejector plate assembly is that part of the mould to which the ejector element is attached.The assembly is contained in a pocket,formed by the ejector grid,directly behind the mould plate.The assembly（Figure5-2）consists of an ejector plate,a retaining plate and an ejector rod.One end of this latter member is threaded and it is screwed into the ejector plate.In this particular design the ejector rod function not only as an actuating member but also as a method of guiding the assembly.Note that the parallel portion of the ejector rod passes through an ejector rod bush fitted in the back plate of the mould.5.2、Ejection techniquesWhen a molding cools,it contracts by an amount depending on the material being processed.For a molding which has no internal form,for example,a solid rectangular block,the molding will shrink away from the cavity walls,thereby permitting a simple ejection technique to be adopted.However,when the molding has internal form,the molding,as it cools,will shrink onto the core and some positive type of ejection is necessary.The designer has several ejection techniques from which to choose，but in general,the choice will be restricted depending upon the shape of the molding.The basic ejection techniques are as follows：（ⅰ）pin ejection（ⅱ）sleeve ejection（ⅲ）stripper plate ejection and（Ⅳ）air ejection.Figure 2-1aFigure 2-1bFigure 3-1Figure 3-2Figure 4-1aFigure 4-1bFigure 5-1Figure 5-2注塑模1、注塑模尽管成型某些热固性材料的方法取得了一定的进步，但注塑模主要（还是）用来生产热塑性塑件。

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外文翻译及原文(文档含英文原文和中文翻译)【原文一】CONCURRENT DESIGN OF PLASTICS INJECTION MOULDS AbstractThe plastic product manufacturing industry has been growing rapidly in recent years. One of the most popular processes for making plastic parts is injection moulding. The design of injection mould is critically important to product quality and efficient product processing.Mould-making companies, who wish to maintain the competitive edge, desire to shorten both design and manufacturing leading times of the by applying a systematic mould design process. The mould industry is an important support industry during the product development process, serving as an important link between the product designer and manufacturer. Product development has changed from the traditional serial process of design, followed by manufacture, to a more organized concurrent process where design and manufacture are considered at a very early stage of design. The concept of concurrent engineering (CE) is no longer new and yet it is still applicable and relevant in today’s manuf acturing environment. Team working spirit, management involvement, total design process and integration of IT tools are still the essence of CE. The application of The CE process to the design of an injection process involves the simultaneous consideration of plastic part design, mould design and injection moulding machine selection, production scheduling and cost as early as possible in the design stage.This paper presents the basic structure of an injection mould design. The basis of this system arises from an analysis of the injection mould design process for mould design companies. This injection mould design system covers both the mould design process and mould knowledge management. Finally the principle of concurrent engineering process is outlined and then its principle is applied to the design of a plastic injection mould.Keywords :Plastic injection mould design, Concurrent engineering, Computer aided engineering, Moulding conditions, Plastic injection moulding, Flow simulation1.IntroductionInjection moulds are always expensive to make, unfortunately without a mould it can not be possible ho have a moulded product. Every mould maker has his/her own approach to design a mould and there are many different ways of designing and building a mould. Surely one of the most critical parameters to be considered in the design stage of the mould is the number of cavities, methods of injection, types of runners, methods of gating, methods of ejection, capacity and features of the injection moulding machines. Mould cost, mould quality and cost of mould product are inseparableIn today’s completive environment, computer aided mould filling simulation packages can accurately predict the fill patterns of any part. This allows for quick simulations of gate placements and helps finding the optimal location. Engineers can perform moulding trials on the computer before the part design is completed. Process engineers can systematically predict a design and process window, and can obtain information about the cumulative effect of the process variables that influence part performance, cost, and appearance.2.Injection MouldingInjection moulding is one of the most effective ways to bring out the best in plastics. It is universally used to make complex, finished parts, often in a single step, economically, precisely and with little waste. Mass production of plastic parts mostly utilizes moulds. The manufacturing process and involving moulds must be designed after passing through the appearance evaluation and the structure optimization of the product design. Designers face a hugenumber of options when they create injection-moulded components. Concurrent engineering requires an engineer to consider the manufacturing process of the designed product in the development phase. A good design of the product is unable to go to the market if its manufacturing process is impossible or too expensive. Integration of process simulation, rapid prototyping and manufacturing can reduce the risk associated with moving from CAD to CAM and further enhance the validity of the product development.3. Importance of Computer Aided Injection Mould DesignThe injection moulding design task can be highly complex. Computer Aided Engineering (CAE) analysis tools provide enormous advantages of enabling design engineers to consider virtually and part, mould and injection parameters without the real use of any manufacturing and time. The possibility of trying alternative designs or concepts on the computer screen gives the engineers the opportunity to eliminate potential problems before beginning the real production. Moreover, in virtual environment, designers can quickly and easily asses the sensitivity of specific moulding parameters on the quality and manufacturability of the final product. All theseCAE tools enable all these analysis to be completed in a meter of days or even hours, rather than weeks or months needed for the real experimental trial and error cycles. As CAE is used in the early design of part, mould and moulding parameters, the cost savings are substantial not only because of best functioning part and time savings but also the shortens the time needed to launch the product to the market.The need to meet set tolerances of plastic part ties in to all aspects of the moulding process, including part size and shape, resin chemical structure, the fillers used, mould cavity layout, gating, mould cooling and the release mechanisms used. Given this complexity, designers often use computer design tools, such as finite element analysis (FEA) and mould filling analysis (MFA), to reduce development time and cost. FEA determines strain, stress and deflection in a part by dividing the structure into small elements where these parameters can be well defined. MFA evaluates gate position and size to optimize resin flow. It also defines placement of weld lines, areas of excessive stress, and how wall and rib thickness affect flow. Other finite element design tools include mould cooling analysis for temperature distribution, and cycle time and shrinkage analysis for dimensional control and prediction of frozen stress and warpage.The CAE analysis of compression moulded parts is shown in Figure 1. The analysis cycle starts with the creation of a CAD model and a finite element mesh of the mould cavity. After the injection conditions are specified, mould filling, fiber orientation, curing and thermal history, shrinkage and warpage can be simulated. The material properties calculated by the simulation can be used to model the structural behaviour of the part. If required, part design, gate location and processing conditions can be modified in the computer until an acceptable part is obtained. After the analysis is finished an optimized part can be produced with reduced weldline (known also knitline), optimized strength, controlled temperatures and curing, minimized shrinkage and warpage.Machining of the moulds was formerly done manually, with a toolmaker checking each cut. This process became more automated with the growth and widespread use of computer numerically controlled or CNC machining centres. Setup time has also been significantly reduced through the use of special software capable of generating cutter paths directly from a CAD data file. Spindle speeds as high as 100,000 rpm provide further advances in high speed machining. Cutting materials have demonstrated phenomenal performance without the use of any cutting/coolant fluid whatsoever. As a result, the process of machining complex cores and cavities has been accelerated. It is good news that the time it takes to generate a mould is constantly being reduced. The bad news, on the other hand, is that even with all these advances, designing and manufacturing of the mould can still take a long time and can be extremely expensive.Figure 1 CAE analysis of injection moulded partsMany company executives now realize how vital it is to deploy new products to market rapidly. New products are the key to corporate prosperity. They drive corporate revenues, market shares, bottom lines and share prices. A company able to launch good quality products with reasonable prices ahead of their competition not only realizes 100% of the market before rival products arrive but also tends to maintain a dominant position for a few years even after competitive products have finally been announced (Smith, 1991). For most products, these two advantages are dramatic. Rapid product development is now a key aspect of competitive success. Figure 2 shows that only 3–7% of the product mix from the average industrial or electronics company is less than 5 years old. For companies in the top quartile, the number increases to 15–25%. For world-class firms, it is 60–80% (Thompson, 1996). The best companies continuously develop new products. AtHewlett-Packard, over 80% of the profits result from products less than 2 years old! (Neel, 1997)Figure 2. Importance of new product (Jacobs, 2000)With the advances in computer technology and artificial intelligence, efforts have been directed to reduce the cost and lead time in the design and manufacture of an injection mould. Injection mould design has been the main area of interest since it is a complex process involving several sub-designs related to various components of the mould, each requiring expert knowledge and experience. Lee et. al. (1997) proposed a systematic methodology and knowledge base for injection mould design in a concurrent engineering environment.4.Concurrent Engineering in Mould DesignConcurrent Engineering (CE) is a systematic approach to integrated product development process. It represents team values of co-operation, trust and sharing in such a manner that decision making is by consensus, involving all per spectives in parallel, from the very beginning of the productlife-cycle (Evans, 1998). Essentially, CE provides a collaborative, co-operative, collective and simultaneous engineering working environment. A concurrent engineering approach is based on five key elements:1. process2. multidisciplinary team3. integrated design model4. facility5. software infrastructureFigure 3 Methodologies in plastic injection mould design, a) Serial engineering b) Concurrent engineeringIn the plastics and mould industry, CE is very important due to the high cost tooling and long lead times. Typically, CE is utilized by manufacturing prototype tooling early in the design phase to analyze and adjust the design. Production tooling is manufactured as the final step. The manufacturing process and involving moulds must be designed after passing through the appearance evaluation and the structure optimization of the product design. CE requires an engineer to consider the manufacturing process of the designed product in the development phase.A good design of the product is unable to go to the market if its manufacturing process is impossible. Integration of process simulation and rapid prototyping and manufacturing can reduce the risk associated with moving from CAD to CAM and further enhance the validity of the product development.For years, designers have been restricted in what they can produce as they generally have todesign for manufacture (DFM) – that is, adjust their design intent to enable the component (or assembly) to be manufactured using a particular process or processes. In addition, if a mould is used to produce an item, there are therefore automatically inherent restrictions to the design imposed at the very beginning. Taking injection moulding as an example, in order to process a component successfully, at a minimum, the following design elements need to be taken into account:1. . geometry;. draft angles,. Non re-entrants shapes,. near constant wall thickness,. complexity,. split line location, and. surface finish,2. material choice;3. rationalisation of components (reducing assemblies);4. cost.In injection moulding, the manufacture of the mould to produce the injection-moulded components is usually the longest part of the product development process. When utilising rapid modelling, the CAD takes the longer time and therefore becomes the bottleneck.The process design and injection moulding of plastics involves rather complicated and time consuming activities including part design, mould design, injection moulding machine selection, production scheduling, tooling and cost estimation. Traditionally all these activities are done by part designers and mould making personnel in a sequential manner after completing injection moulded plastic part design. Obviously these sequential stages could lead to long product development time. However with the implementation of concurrent engineering process in the all parameters effecting product design, mould design, machine selection, production scheduling,tooling and processing cost are considered as early as possible in the design of the plastic part. When used effectively, CAE methods provide enormous cost and time savings for the part design and manufacturing. These tools allow engineers to virtually test how the part will be processed and how it performs during its normal operating life. The material supplier, designer, moulder and manufacturer should apply these tools concurrently early in the design stage of the plastic parts in order to exploit the cost benefit of CAE. CAE makes it possible to replace traditional, sequential decision-making procedures with a concurrent design process, in which all parties can interact and share information, Figure 3. For plastic injection moulding, CAE and related design data provide an integrated environment that facilitates concurrent engineering for the design and manufacture of the part and mould, as well as material selection and simulation of optimal process control parameters.Qualitative expense comparison associated with the part design changes is shown in Figure 4 , showing the fact that when design changes are done at an early stages on the computer screen, the cost associated with is an order of 10.000 times lower than that if the part is in production. These modifications in plastic parts could arise fr om mould modifications, such as gate location, thickness changes, production delays, quality costs, machine setup times, or design change in plastic parts.Figure 4 Cost of design changes during part product development cycle (Rios et.al, 2001)At the early design stage, part designers and moulders have to finalise part design based on their experiences with similar parts. However as the parts become more complex, it gets rather difficult to predict processing and part performance without the use of CAE tools. Thus for even relatively complex parts, the use of CAE tools to prevent the late and expensive design changesand problems that can arise during and after injection. For the successful implementation of concurrent engineering, there must be buy-in from everyone involved.5.Case StudyFigure 5 shows the initial CAD design of plastics part used for the sprinkler irrigation hydrant leg. One of the essential features of the part is that the part has to remain flat after injection; any warping during the injection causes operating problems.Another important feature the plastic part has to have is a high bending stiffness. A number of feeders in different orientation were added to the part as shown in Figure 5b. These feeders should be designed in a way that it has to contribute the weight of the part as minimum aspossible.Before the design of the mould, the flow analysis of the plastic part was carried out with Moldflow software to enable the selection of the best gate location Figure 6a. The figure indicates that the best point for the gate location is the middle feeder at the centre of the part. As the distortion and warpage of the part after injection was vital from the functionality point of view and it has to be kept at a minimum level, the same software was also utilised to yiled the warpage analysis. Figure 5 b shows the results implying the fact that the warpage well after injection remains within the predefined dimensional tolerances.6. ConclusionsIn the plastic injection moulding, the CAD model of the plastic part obtained from commercial 3D programs could be used for the part performance and injection process analyses. With the aid ofCEA technology and the use of concurrent engineering methodology, not only the injection mould can be designed and manufactured in a very short of period of time with a minimised cost but also all potential problems which may arise from part design, mould design and processing parameters could be eliminated at the very beginning of the mould design. These two tools help part designers and mould makers to develop a good product with a better delivery and faster tooling with less time and money.References1. Smith P, Reinertsen D, The time-to-market race, In: Developing Products in Half the Time. New York, Van Nostrand Reinhold, pp. 3–13, 19912.Thompson J, The total product development organization. Proceedings of the SecondAsia–Pacific Rapid Product Development Conference, Brisbane, 19963.Neel R, Don’t stop after the prototype, Seventh International Conference on Rapid Prototyping, San Francisco, 19974.Jacobs PF, “Chapter 3: Rapid Product Development” in Rapid Tooling: Technologies and Industrial Applications , Ed. Peter D. Hilton; Paul F. Jacobs, Marcel Decker, 20005.Lee R-S, Chen, Y-M, and Lee, C-Z, “Development of a concurrent mould design system: a knowledge based approach”, Computer Integrated Manufacturing Systems, 10(4), 287-307, 19976.Evans B., “Simultaneous Engineering”, Mechanical Engi neering , V ol.110, No.2, pp.38-39, 19987.Rios A, Gramann, PJ and Davis B, “Computer Aided Engineering in Compression Molding”, Composites Fabricators Association Annual Conference , Tampa Bay, 2001【译文一】塑料注塑模具并行设计塑料制品制造业近年迅速成长。