Mold Design - Alpine Mold

Alpine mold’s Mold Design & Engineering Support

At Alpine Mold, we offer high-quality early-stage engineering support, starting from efficient injection mold design. We have invested significantly in professional talent and technology, with an engineering team boasting over 10 years of experience, to provide tailor-made solutions to meet your project requirements and assist you at every step.

The Engineering Software Used At Alpine mold:

Pro-E
Solidworks
AutoCAD

In addition, we use universal formats such as:

IGES
STEP
x_t
STL

We also work with your 2d/3d drawings, sketches, models, physical parts, or existing molds to align with our unbeatable quality and service!

Professional Value-Added Services in Mold Design

DFM Report and Mold Flow Analysis

In our mold design services, we not only strive to provide customers with high-quality mold design solutions but also focus on providing comprehensive support and guarantees through a series of professional analyses and reports to ensure the optimization of mold design and products. Ultimately, high-quality products and efficient production can be achieved. Eventually, it helps customers to have competitive products with both high cost-performance and high quality.

I. Design for Manufacturability

(I) What is DFM?

The DFM report is an important document that comprehensively evaluates and optimizes product design during the mold design stage to ensure that the product can be manufactured more efficiently and economically. From the perspective of manufacturing results, it considers various factors such as product surface requirements, structure, materials, assembly processes, etc., and discovers and solves potential problems that may occur during the production process in advance, thereby reducing trial-and-error costs and production costs, shortening the production cycle, and improving product quality and production efficiency.

(II) Contents of the DFM Report

Product Structure Analysis

i. Evaluate the overall structure of the product to check if there are complex structures or difficult-to-process parts that are not conducive to manufacturing. For example, for products with internal undercut structures, we will point out in the report and recommend appropriate demolding methods, such as slider or lifter structures, and analyze the impact of these structures on mold design and manufacturing.

ii. Evaluate the wall thickness uniformity of each part of the product. Uneven wall thickness may lead to problems such as uneven shrinkage and deformation during the injection molding process. We will provide suggestions for optimizing wall thickness in the report to ensure the stability of the product during the molding process.

Material Selection and Evaluation

i. Evaluate the materials selected by the customer according to the usage requirements and performance characteristics of the product. Analyze factors such as the processing performance, molding characteristics, and cost of the materials to ensure that the selected materials not only meet the functional requirements of the product but also have good manufacturability and economy.

ii. If potential problems are found with the materials selected by the customer, we will recommend more suitable alternative materials in the report and explain the reasons for the recommendation in detail, including the performance advantages of the materials, cost differences, and the impact on the production process.

Molding Process Analysis

i. Select the best gate location and gate type. This is beneficial for obtaining products with the minimum internal stress, minimum deformation, and the best appearance.

ii. Design the best ejection mechanism. This is beneficial for obtaining the best product appearance and improving production efficiency and reducing the manufacturing cost of the mold.

iii. Design the best cooling system. This is beneficial for obtaining products with the minimum deformation and for improving the production efficiency of the product.

iv. Design the best exhaust system. This is beneficial for obtaining the best surface effect and for improving the production efficiency of the product.

v. Design the best lubrication system. This is beneficial for the long-term smooth operation of the mold, reducing failures, and improving production efficiency.

Manufacturing Process Analysis

i. Select the best manufacturing process for the structure of the mold. It is necessary to consider the processing difficulty, processing precision, and feasibility analysis of the mold. For example, for some mold parts with high precision requirements, we will select the optimal processing solution according to the existing processing equipment. If necessary, we will recommend special processing methods or processes for optimization.

ii. Analyze the mold assembly process to ensure that each part of the mold can be accurately and smoothly assembled. In the report, suggestions for the assembly sequence and assembly method will be provided, as well as the key points and difficulties that may need to be noted during assembly.

Cost Analysis and Optimization Suggestions

i. Analyze the manufacturing cost of the mold in detail, including material costs, processing costs, assembly costs, etc. Through the analysis of the cost structure, find the links that may reduce costs and put forward corresponding optimization suggestions.

ii. For example, by optimizing the mold structure design, reducing the number of mold parts or simplifying the processing process, thereby reducing the processing cost; or choosing more economical materials without affecting product quality, reducing the material cost.

II. Mold Flow Analysis

(I) The Significance of Mold Flow Analysis

Mold flow analysis is a method that uses computer simulation technology to simulate and analyze the flow, filling, packing, and cooling processes of plastics in injection molds. It can help mold designers predict problems that may occur during the plastic molding process, such as short shots, flash, bubbles, stress concentrations, etc., during the design stage, thereby optimizing the mold design solution and improving the quality and efficiency of injection molding.

(II) The Process and Results of Mold Flow Analysis

1. Model Establishment and Preprocessing

i. First, according to the three-dimensional product model provided by the customer, we will establish a mold flow analysis model. Mesh the model to ensure that the mesh quality meets the analysis requirements. At the same time, set the properties of the plastic material, injection process parameters (such as injection pressure, temperature, speed, etc.), and mold str

2. Simulation Analysis and Calculation

i. Run the mold flow analysis software to simulate and calculate the molding process of plastics in the mold. The software will calculate key data such as the flow trajectory of the plastic melt in the mold, pressure distribution, temperature distribution, filling time, packing curve, etc., according to the set parameters and physical models.

3. Results Analysis and Optimization Suggestions

i. Filling Process Analysis: By analyzing the simulation results of the filling process, we can check whether the plastic melt can uniformly fill each part of the mold cavity. If it is found that the filling is unbalanced, it may lead to problems such as short shots or local density unevenness in the product. In the report, we will provide suggestions for optimizing the gate position, size, or runner system to improve the filling effect.

ii. Pressure Distribution Analysis: The pressure distribution situation directly affects the quality of injection molding and the life of the mold. Excessive pressure may lead to mold damage or product flash and other defects, while too low pressure may lead to short shots or poor product quality. We will evaluate the strength and structural rationality of the mold according to the pressure distribution results and put forward corresponding improvement measures, such as adjusting injection process parameters or optimizing the mold structure.

iii. Temperature Distribution Analysis: Uneven temperature distribution may cause problems such as uneven shrinkage, deformation, or internal stress concentration in the product. Through mold flow analysis, we can understand the temperature change situation of the mold during the injection process, optimize the cooling system design, ensure that the product can be uniformly cooled, and improve the product's dimensional accuracy and appearance quality. In the report, we will provide suggestions for the layout of cooling channels, the selection of cooling media, and the optimization of cooling time.

iv. Bubbles and Fusion Lines Analysis: Bubbles and fusion lines are common defects in injection molding and will affect the product's appearance and strength. Mold flow analysis can predict the position and number of bubbles and fusion lines. We will according to the analysis results suggest adjusting injection process parameters or mold structure, such as adding vent holes, optimizing the gate position, etc., to reduce or eliminate these defects.

The Design Process of Plastic Injection Molds

I. Product Analysis and Demand Assessment

1. Research on Product Specifications

We will first conduct in-depth research on the product specifications provided by the customer, including the product's size, shape, wall thickness, tolerance requirements, etc. For example, if the product is a plastic shell with a complex internal structure, we need to accurately measure the size of each part and determine the allowable tolerance range, which is crucial for ensuring product accuracy in subsequent mold design.

2.Consideration of Material Characteristics

Understand the characteristics of the plastic materials required for the product. Different plastic materials have different shrinkage rates, fluidity, strength, etc. For example, polypropylene materials have good toughness and high fluidity, while ABS materials have high hardness and good surface gloss. According to these characteristics, determine the type of gate and the size of the runner system of the mold to ensure that the plastic can be filled smoothly in the mold

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3.Analysis of Production Volume Requirements

Determine the number of cavities of the mold according to the customer's production volume requirements. If the customer requires large-scale production, we will recommend a multi-cavity mold to the customer to improve production efficiency.

II. Conceptual Design

1.Determination of the Parting Surface

The parting surface is the interface between the upper and lower molds or the moving and fixed molds. The appropriate parting surface should be selected according to the shape of the product. The general principle is to ensure that the product can be demolded smoothly as much as possible, and the parting surface should be as simple and flat as possible. However, for products with more complex undercut structures, special consideration should be given to the position of the parting surface, and structures such as sliders or lifters need to be used to achieve demolding.

2. Selection of the Gate Location and Type

The gate is the entrance for the plastic melt to enter the mold cavity. The selection of the gate location should consider the flow balance of the plastic and the appearance requirements of the product.

3. Preliminary Structural Layout

Determine the basic structure of the mold, including the layout of the cavities and cores, and whether special structures such as sliders, lifters, inserts, etc. need to be adopted. For products with lateral protrusions or internal undercut structures, slider or lifter structures need to be designed to achieve the smooth demolding of the product.

III. Detailed Design

1. Design of Cavities and Cores

Accordingly to the shape and size of the product, accurately design the shape and size of the cavities and cores, and consider the shrinkage rate of the plastic for appropriate size compensation. At the same time, calculate the strength and stiffness of the cavities and cores to ensure their stability during the injection molding process.

2. Design of the Runner System

The runner system includes the sprue, runner, and gate. The sprue is the channel connecting the nozzle of the injection machine and the runner, and its size is determined according to the specification of the injection machine and the flow of the plastic. The design of the runner should ensure that the plastic melt can flow uniformly and quickly to each cavity in the runner, and its diameter, length, and roughness will affect the flow characteristics of the plastic.

3. Design of the Cooling System

The design purpose of the cooling system is to make the plastic cool and set quickly in the mold. The cooling channels should be arranged according to the shape and wall thickness of the product. Generally, the cooling channels should be as close as possible to the cavity surface, and the distance between the channels should be uniform. For example, for products with thicker wall thickness, the spacing of the cooling channels can be appropriately increased; while for thin-wall products, a more dense layout of cooling channels is required.

4. Design of the Demolding Institution

The demolding institution is used to push the molded product out of the mold. Besides the common push rod demolding institution, for products with complex structures, such as those with lateral core-pulling structures, the driving institutions of sliders and lifters need to be designed, such as using inclined guide pins, hydraulic or pneumatic devices to drive the movement of sliders and lifters, ensuring that the product can be demolded smoothly.

IV. Design Review

1. Internal Review

The design manager of our internal engineering team reviews the design scheme, mainly checking whether the design meets the manufacturability requirements of the mold, whether the structure is reasonable, and whether there are potential design defects, etc. For example, checking whether the runner system will cause an unbalanced flow of plastic, whether the demolding institution can work reliably, etc.

2. Review through Communication with the Customer

The runner system includes the sprue, runner, and gate. The sprue is the channel connecting the nozzle of the injection machine and the runner, and its size is determined according to the specification of the injection machine and the flow of the plastic. The design of the runner should ensure that the plastic melt can flow uniformly and quickly to each cavity in the runner, and its diameter, length, and roughness will affect the flow characteristics of the plastic.

V. Drawing of Mold Manufacturing Drawings

1. Drawing of Part Drawings

Draw detailed drawings of each part of the mold, including information such as the part's size, tolerance, surface roughness, material, heat treatment requirements, etc. The part drawings should be detailed and accurate for easy manufacturing and processing. For example, for the core part in the mold, clearly mark its shape size, the fitting size with other parts, and the processing accuracy requirements, etc.

2.Drawing of Assembly Drawings

Draw the assembly drawing of the mold, showing the assembly relationships, assembly sequence, and overall structure among the various parts of the mold. In the assembly drawing, mark the main assembly sizes, fitting tolerances, etc., to provide clear guidance for the mold's assembly.

VI. Design Verification and Optimization

1. Trial Molding

After the mold is manufactured, conduct a trial molding operation. During the trial molding process, observe the filling situation of the plastic in the mold (make a flow plate), the molding quality of the product (including size accuracy, appearance quality, whether there are defects, etc.), and the working performance of the mold (such as whether demolding is smooth, whether the cooling effect is good, etc.).

2. Optimization and Adjustment

According to the trial molding results, optimize and adjust the mold. If it is found that the product has defects, such as flash, shrink marks, etc., analyze the reasons and modify the corresponding parts of the mold, such as adjusting the gate size, optimizing the layout of the cooling channels, etc. Through multiple trial moldings and optimizations, until the mold produces products that meet the customer's quality requirements.

What Excellent Design Can Bring You

Our experienced design engineers can prevent some defects in the mold design in advance to achieve the perfect mold.

High Tolerance

Our excellent design engineers can make our mold precision reach 0.01mm through mold design.

Low Defective Rate

Engineers consider different aspects of the production process, including injection rate, temperature, runner presence, and gate type, to reduce mold defectivity.

Cost Saving Production

Through the refined design of the mold, we eliminate the waste of excess material and poor output, and also reduce the production cost.

Fast Turnaround

Good mold design reduces possible problems in the production process, improves the speed of product production, and can meet customer delivery time in time.