Papers by Keyword: Gating System

Abstract: The purpose of this paper is to obtain the best process parameters of polypropylene bottle injection molding. This paper obtained the gating system of polypropylene bottle embryo by using MOLDFLOW according to the structural characteristics of polypropylene bottle embryo, and optimized the process parameters by using taguchi method within the reasonable range of process parameters. In this paper, six parameters about time, pressure and temperature were selected as factors for the mold flow analysis of polypropylene bottle embryo injection molding, and there were four levels in every factor. The volume shrinkage, sink index and residual stress in the first and second directions in the cavity were selected as evaluation indexes. In order to reduce evaluation indexes, the signal to noise ratio of each factor and each level were calculated, and the adjustable factors were adjusted to obtain the minimum evaluation indexes and optimal combination of process parameters. The optimum process parameters such as melt temperature 200°C, molding temperature 20°C, injection pressure 50Mpa, injection time 2.1s,dwell pressure 44Mpa, dwell time 40s were gained.

Abstract: There are two new processes to development automobile structural components which have certain thickness. In the present paper, taking a main bearing cap product as an example, analyses die design by comparing the experimental and computational numerical simulation results. For the main bearing cap, product structure and mold design were designed to be suitable for characters of SSM die casting and squeeze process. Semi-solid slurry has significantly higher viscosity than liquid metal. This character of fluidity and solid fraction phase make the flow condition more laminar than liquid squeeze casting with the partial fill experiment. And compared with squeeze casting process, the globular shape grain size is smaller than dendritic structure. And mechanical property result shows that the elongation of SSM die casting can achieve more than twice than squeeze casting.

Abstract: Selection of an appropriate gating system for a consumable pattern is a long and time-consuming process that requires considerable effort. Advanced design technologies can be used to design the gating system and to simulate the casting process based on the design. Simulation and design of the gating system allow detection of types of defects in the casting at the development stage. Parametrical changing of the gating system 3D model and variation of its characteristics, and repeated simulation of cooling, crystallization and mold filling processes can provide high quality casting.

Abstract: The casting processes are characterized by complex relationships between predictors and responses. It is the fundamental understanding of these complex relationships that often involves hundreds of factors, which improves quality without losing productivity and raising cost. In this work, cast solid solution strengthened ferritic spheroidal graphite irons GJS-500-14 and GJS-600-10 (EN 1563:2012) have been evaluated. These materials offer stronger components with good machinability owing to their even hardness properties. In this case the predictors are chemical composition, gating layout, foundry set-up, testing procedure and equipment etc. and the responses are the tensile properties (R_p0.2, R_m, A₅). Here 200 tensile specimens compiled from industrial foundry melts from over 30 years of research have created a state-of-the-art platform for statistical engineering in order to perform Exploratory Data Analysis (EDA) and data visualization. This statistical platform has provided new insight on how foundries should treat complex relationships between predictors and responses in order to identify sources of variation and interaction effects.

Abstract: GTD222 superalloy is a potential candidate for large-scale complex thin-walled castings with high temperature resistance in the next-generation aircraft engines, due to its excellent creep performance, good oxidation resistance and favorable weldability. The precision casting of GTD222 with a complex thin-wall structure was investigated in this work. The good quality of the final cast indicated that the optimized gating system obtained by numerical simulation was satisfying.

Abstract: Semi-solid slurry has significantly higher viscosity than liquid metal. This character of fluidity makes product design and die design, such as gating system, overflow and venting system, be different between these two die casting processes. In the present paper, taking a clamp product as an example, analyses the product optimization and die design by comparing the experimental and computational numerical simulation results. For the clamp, product structure is designed to be suitable for characters of SSM die casting process. The gating system is designed to be uniform variation of thickness, making the cross-sectional area uniformly reduce from the biscuit to the gate. This design ensures semi-solid metal slurry to fill die cavity from thick wall to thin wall. Gate position is designed at the thickest location, the gate shape of semi-solid die casting is set to be much bigger than traditional liquid casting. A good filling behaviour can be achieved by aforementioned all these design principles and it will be helpful to the intensification of pressure feeding after filling.

Abstract: The simulation process of centrifugal casting using titanium aluminide intermetallic alloys has been described in the context of the low-pressure duct turbine blade designed for the gas-turbine engine. Initially, the preliminary theoretical calculations have been performed together with experimental casting when developing the casting production technologies. The obtained results allowed setting a range of the boundary conditions for computing simulation of pouring and solidification. ProCast the computing simulation system for the casting processes has been used. Various alternatives of the casting layout in the mold as well as the gating system configurations have been examined by means of this system. In the course of simulation process such faults have been detected as formation of shrinkages into the shroud platform and (or) blade footing; or significant decrease in technological yield when the risers’ dimensions expand or the casts’ number decreases in the mold. Considering the results of the performed computer experiments, the most efficient gating system has been ultimately defined to obtain the casts using titanium aluminide intermetallic alloys by centrifugal casting.

Abstract: Systematic change of riser size together with variation of thickness and length of A201 aluminum alloy plate castings were studied to investigate the correlation between mechanical properties and porosity content. The molds with end chill for plate castings were made of 100% chromite sand by CO₂ process. If soundness throughout the whole plate casting has to be guaranteed, the riser diameter should be proper design to the dimension of the plate. The tensile strength and elongation of A201 aluminum alloy plate casting is governed by riser diameter, thickness, and length of the plate.

Abstract: Die casting processing analysis was conducted and the gating system and the cooling system were designed for aluminum alloy gearbox housings. Numerical simulation software PROCAST was used to calculate the filling and solidification sequence and the temperature field of die castings. The reasonable designs of the gating system and the cooling system were obtained. The feasible die casting mould was designed and manufactured. Production trial showed that, casting molding effect is good, and there were not defects such as misrun, cold lap. After machining, there were not defects exceeding the allowed limited values including porosity, shrinkage, and slag inclusion in the products. The trial showed that the product mold design and die casting technology achieved the desired effect, which can realize batch production.

Abstract: The gating system of an injection mold for car bumper was studied. A design optimization scheme is proposed to optimize both the number and locations of the gates by analyzing the filling process, in order to reduce the part war page and weld line, numerical simulation of injection mold filling process is combined with the design optimization method to find the optimum number of gates and their locations to achieve balanced f low and less weld lines while satisfying the limit of injection pressure. Moldflow software was applied to make analysis and comparison of various gating system in terms of their filling time, injection pressure and clamp force, weld line and distribution of air traps, and an optimized gating system was obtained. The result shows that this method can effectively reduce costs, shorten development cycle and improve the efficiency of molding design.