PET Mold Design Decorative Performance, The Necessary Flexibility
First, accept the task book
The task book for forming a plastic part is usually made by the part designer, as follows:
1. The approved formal parts drawings and the use of plastic grades, transparency and so on.
2. Plastic parts manual or technical requirements.
4. Sample of plastic parts.
Usually the PET mold design task book by the plastic parts craftsmen according to the task of forming plastic parts of the task book, PET mold design staff to shape the plastic parts of the task book, PET mold design task book based on the design of the mold.
Second, the collection, analysis, digest the original data
Collection and finishing of the relevant parts design, molding process, molding equipment, machining and special processing materials to prepare for the use of PET mold design.
1. Digestive plastic parts drawing, to understand the use of parts, analysis of plastic parts of the process, dimensional accuracy and other technical requirements. Such as plastic parts in the appearance of the shape, color transparency, the use of performance requirements What is the plastic parts of the geometric structure, slope, insert, etc. are reasonable welds, shrinkage and other defects in the formation of defects, Equipment, electroplating, bonding, drilling and other post-processing. Select the plastic parts of the size of the highest dimensional accuracy of the analysis to see if the estimated molding tolerance is lower than the plastic parts of the tolerance, whether to meet the requirements of the plastic parts to meet. In addition, but also to understand the plastic plastic molding process parameters.
2. digestion process information, analysis of the work of the task book proposed by the molding method, equipment model, material specifications, mold structure type and other requirements are appropriate can implement. Molding materials should meet the strength requirements of plastic parts, with good mobility, uniformity and isotropic, thermal stability. According to the use of plastic parts,PET mold design molding materials should meet the requirements of dyeing, metallizing conditions, decorative properties, necessary elasticity and plasticity, transparency or opposite reflective properties, adhesiveness or weldability requirements.
3. Determine the molding method
Using direct pressure method, casting method or injection method.
4. Select the forming equipment
According to the type of molding equipment to carry out the mold, it is necessary to know a variety of molding equipment performance, specifications, features. For example, for the injection machine, the following should be understood in terms of specifications, injection capacity, clamping pressure, injection pressure,PET mold design mold mounting dimensions, ejector and size, nozzle hole diameter and nozzle spherical radius, gate sleeve positioning ring size, The maximum thickness of the mold and the minimum thickness, the template travel, see the relevant parameters. To estimate the mold size, determine whether the mold can be installed and used on the selected injection machine.
5. Specific structure program
① determine the type of mold
Such as compression mold, open, semi-closed, closed, casting die, injection mold and so on.
② determine the main structure of the mold type
The ideal mold structure is to determine the necessary molding equipment, the ideal number of cavity in the absolute conditions can make the work of the mold itself to meet the plastic parts of the process technology and production economy requirements. The technical requirements for plastic parts are to ensure that the plastic parts of the geometric shape, surface finish and dimensional accuracy. Production of economic requirements is to make plastic parts of the low cost, high production efficiency, mold can work continuously, long life, save labor.
Third, the impact of mold structure and mold individual system factors are very complex
1. cavity layout. According to the geometric structure of plastic parts, dimensional accuracy requirements, batch size, mold manufacturing difficulties, mold costs to determine the number of cavities and their arrangement. For the injection mold, the precision of plastic parts for the 3 and 3a, the weight of 5 grams,PET mold design the use of hardening pouring system, the number of cavity to take 4-6, plastic parts for the general accuracy of 4-5, forming materials Local crystallization material, the number of cavity up to 16-20, the weight of plastic parts 12-16 grams, the number of cavity to take 8-12, and the weight of 50-100 grams of plastic parts, cavity number to take 4- 8.
For the amorphous plastic parts recommended cavity number is 24-48, 16-32 and 6-10. When you continue to increase the weight of plastic parts rarely use multi-cavity mold. 7-9 grade precision plastic parts up to the number of cavity than the specified 4-5 grade precision plastic increased to 50%.
2. Determine the parting surface. The position of the parting surface should be beneficial to the mold processing, exhaust, stripping and forming operation, and the surface quality of the plastic parts.
3. Determine the pouring system: the main runner, sub-runner and gate shape, location, size and exhaust system, exhaust method, exhaust slot location, size .
4. Select the top way: mandrel, jacking, push plate, combined top out, determine the side concave processing methods, core pulling mode.
5. Determine the cooling, heating mode and heating the cooling groove shape, location, heating components of the installation site.
6. According to the mold material, strength calculation or empirical data determine the thickness of the mold parts and dimensions, shape structure and all connections, positioning, guide parts position.
7. Determine the main form parts, structural parts of the structure.
8. Consider the strength of each part of the mold Calculate the working size of the molded parts. These problems if the solution to the structure of the mold naturally resolved. At this time should be drawn to draw the mold structure sketch for the formal drawing to prepare.
Fourth, draw the mold map
Requirements in accordance with the national standard drawing But also requires the combination of factory standards and the state does not specify the factory custom painting. Before drawing the drawing of the mold, the drawing should be drawn and the requirements of the parts drawing and process data should be met. The dimensions guaranteed by the next procedure shall be marked on the drawing with the words "process size". If the molding in addition to repair the burr, and then do not carry out other mechanical processing, then the process diagram and parts of the same map.
In the process diagram below the best marked part number, name, material, material shrinkage, drawing ratio. Usually the process picture is drawn on the mold assembly diagram. Draw the assembly diagram as far as possible using the ratio of 1: 1, the first began to draw the cavity, PET mold design the main view and other views at the same time to draw.
Fifth, the mold assembly diagram should include the following
1. Mold forming part of the structure;
2. The structure of the pouring system and the exhaust system;
3. Partial surface and parting mode;
4. Outline structure and all connections, positioning, orientation of the guide;
5. Mark the cavity height size (not required) according to the needs and the overall size of the mold;
6. Auxiliary tools, pickup tools, correction tools, etc .;
7. Order all parts in sequence, and fill in the schedule;
8. Mark technical requirements and instructions.
Six, mold assembly diagram of the technical requirements
1. For some of the performance requirements of the mold. Such as the ejection system, the requirements of the assembly of the slider core structure.
2. Requirements for mold assembly process. For example, the fitting surface of the fitting surface of the mold after fitting shall be not more than 0.05mm on the mold,PET mold design below the parallelism requirements, and indicate the size determined by the assembly and the size of the requirements.
3. Mold use, assembly and disassembly method.
4. Anti-oxidation treatment, mold number, lettering, marking, oil seal, storage and other requirements.
5. Requirements for test and inspection.
Seven, drawing all parts map
The order of drawing parts from the mold assembly diagram should be the first inside, the first complex after the simple, first shape parts after the structural parts.
1. Graphic requirements: must be scaled to allow zoom in or out. View the selection is reasonable, the projection is correct, properly arranged. In order to make the processing patent number easy to understand, easy to install graphics as much as possible with the assembly diagram, graphics to be clear.
2. Dimension requires uniform, centralized, orderly and complete. Mark the size of the order of the main standard for the main parts of the size and out of the mold slope, and then marked with the size, and then marked all the size. In the non-main parts of the map marked with the first size, after all the dimensions.
3. Surface roughness: the most applied to a roughness in the upper right corner of the drawing, such as the label "the remaining 3.2." Other roughness symbols in the parts of the surface were marked.
4. Other content: such as part name, mold number, material grade,PET mold design heat treatment and hardness requirements, surface treatment, graphics ratio, free size of the processing accuracy, technical instructions, etc. should be filled out correctly.