FIG mold engineering methods include

FIG mold engineering methods include what
is generally a process, given the task of the book
　　task book molded plastic parts are usually made by a designer article, which reads as follows:
　　　⑴ formal drawings Shenqian article made of plastic and indicate grades , Transparency, etc.
　　　⑵Instructions or technical requirements for plastic parts.
　　　⑶ Production output.
　　　⑷Samples of plastic parts.
　　Usually the mold design task book is proposed by the plastic part craftsman according to the task book of the molded plastic part, and the mold designer designs the mold based on the task book of the molded plastic part and the plastic crate mould design task book.
Second, the collection, analysis, digested raw data
　　collected article design, molding, molding equipment, machining and special processing, information concerning the design of the mold to prepare for use.
　
　⑴ Digest the drawings of plastic parts, understand the purpose of the parts, analyze the technical requirements of the plastic parts, such as the processability and dimensional accuracy. For example, what are the requirements for plastic parts in terms of appearance, color transparency, and performance,
whether the geometric structure, slope, and inserts of the plastic parts are reasonable, the allowable degree of molding defects such as weld marks and shrinkage holes, and whether they are coated or not. Post-processing such as assembly, electroplating, bonding and drilling. Select the highest dimensional accuracy of the size of the plastic parts is divided
analyzed, to see whether the estimated tolerances molded plastic parts is less than the tolerance, whether the molding plastic parts be desirable. In addition, we must understand the plasticization and molding process parameters of plastics.
　　(2) Digest the process data, analyze whether the molding method, equipment model, material specification, mold structure type and other requirements proposed in the process task book are appropriate and whether they can be implemented.
　　The molding material should meet the strength requirements of plastic parts, and have good fluidity, uniformity, isotropy, and thermal stability. According to the purpose of the plastic parts, the molding material should meet the requirements of dyeing, metal plating, decorative properties, necessary elasticity and plasticity, transparency or opposite reflective properties, adhesiveness or weldability.
Three, determine the molding method
　　Use direct pressure method, casting method or injection method.
Fourth, the choice molding apparatus
　
　to mold according to the kind of the molding apparatus, and therefore must be familiar with all kinds of equipment performance, specifications, characteristics. For example, for an injection machine, the following should be understood in terms of specifications: injection capacity, clamping pressure,
injection pressure, mold installation size, ejection device and size, nozzle hole diameter and nozzle spherical radius, sprue sleeve positioning ring size, The maximum and minimum mold thickness, template stroke, etc., please refer to relevant parameters for details.
　　It is necessary to preliminarily estimate the dimensions of the mold and determine whether the mold can be installed and used on the selected injection machine.
Fifth, the specific configuration of the program:
　⑴ determining the type of mold
　　　, such as compressed mode (open Semi-Enclosed closed type), die casting, injection molding and the like.
　　⑵ determine the main structure of the mold type
　
　　selection is to determine the desired mold structure of the molding apparatus required, the ideal number of cavities, the mold itself can work to meet the requirements of process technology and economic production of the plastic parts under conditions of absolute reliability . The
technological requirements for plastic parts are to ensure the geometric shape, surface finish and dimensional accuracy of plastic parts. The economic requirements of production are to make the cost of plastic parts low, high production efficiency, molds can work continuously,
long service life , and labor saving.
　　There are many factors that affect the mold structure and individual mold systems, and they are very complex:
　　　① Cavity layout. Determine the number of cavities and their arrangement according to the geometric structure characteristics of the plastic parts, dimensional accuracy requirements, batch size, mold manufacturing difficulty, and mold cost.
　
　　For injection molds, the precision of plastic parts is 3 and 3a, the weight is 5 grams, and the hardening casting system is adopted, and the number of cavities is 4-6; the plastic parts are of general precision (level 4-5), forming material is a partial junction
polycrystalline material, the number of the cavity is desirable
16-20 pieces; the weight of plastic parts is 12-16 grams, and the number of cavities is 8-12; and the weight of plastic parts is 50-100 grams, the number of cavities is 4-8. The recommended number
of cavities for amorphous plastic parts is 24-48, 16-32 and 6-10. When the weight of plastic parts continues to increase, multi-cavity molds are rarely used. For plastic parts with 7-9 accuracy, the maximum number of cavities is
increased to 50% compared to the plastic with 4-5 accuracy indicated .
　　　② Determine the parting surface. The position of the parting surface should be conducive to mold processing, venting, demolding and molding operations, and the surface quality of plastic parts.
　　　③Determine the pouring system (shape, location, size of main runner, sub-runner and gate) and exhaust system (exhaust method, position and size of exhaust slot).
　　　④Select the ejection method (ejector, pipe, push plate, combined ejector), determine the undercut treatment method and core pulling method.
　　　⑤Determine the cooling and heating method, the shape and position of the heating and cooling groove, and the installation location of the heating element.
　　　⑥According to the mold material, strength calculation or empirical data, determine the thickness and dimensions of the mold parts, the shape structure and all connections, positioning, and guide positions.
　　　⑦Determine the structural form of main forming parts and structural parts.
　　　⑧Considering the strength of each part of the mold, calculate the working size of the molded part.
　　If these problems are solved, the structure of the mold will naturally be solved. At this time, you should start to draw a sketch of the mold structure to prepare for the formal drawing.
　　　⑨ drawing mold FIG
　　　　claim drawn national mapping standards, but also require binding customary painting plant factory is not specified in the standard and the country.
　　　　Before drawing the mold assembly drawing, the process drawing should be drawn, and it should meet the requirements of the part drawing and process data. The size guaranteed by the next process should be marked with the words "process size" on the drawing. If there is no other mechanical processing except repairing the burrs after molding, the process drawing is exactly the same as the part drawing.
　　　　It is better to mark the part number, name, material, material shrinkage rate, drawing ratio, etc. under the process drawing. Usually the process drawing is on the mold assembly drawing.
　　　　A, the structure of FIG drawing assembly
　　　　　　drawing FIG assembly possible scale of 1: 1, first cavity start drawing, a front view and other views shown simultaneously.
　　　　　　The mold assembly drawing should include the following:
　　　　　　①The structure of the mold forming part
　　　　　　②The structure of the pouring system and the exhaust system.
　　　　　　③Parting surface and way of parting and taking parts.
　　　　　　④Outline structure and all connecting parts, positioning and guiding parts.
　　　　　　⑤Mark the height dimension of the cavity (not mandatory, as required) and the overall dimensions of the mold.
　　　　　　⑥ Auxiliary tools (tools for removing molds, correction tools, etc.).
　　　　　　⑦Compile the serial numbers of all parts in order and fill in the detailed list.
　　　　　　⑧ Mark technical requirements and instructions for use.
　　　　B. The technical requirements of the mold assembly drawing:
　　　　　　①The performance requirements of certain systems of the mold. For example, the assembly requirements for ejector system and slider core pulling structure.
　　　　　　②Requirements for mold assembly process. For example, after the mold is assembled, the bonding gap of the bonding surface of the parting surface should not be greater than the parallelism requirements of the upper and lower sides of the mold of 0.05mm, and indicate the size determined by the assembly and the requirements for this size.
　　　　　　③Using the mold, assembling and dismantling method.
　　　　　　④ Anti-oxidation treatment, mold numbering, lettering, marking, oil seal, storage and other requirements.
　　　　　　⑤ Requirements related to mold trial and inspection.
　　　　C. Draw all parts diagram
　　　　　　The sequence of disassembling and drawing the parts drawing from the mold assembly drawing should be: inside first, then outside, first complicated then simple, forming parts first, then structural parts.
　　　　　　①Graphic requirements: must be drawn to scale, allowing zoom in or zoom out. The view selection is reasonable, the projection is correct, and the layout is appropriate. In order to make the processing patent number easy to understand and easy to assemble, the graphics should be as consistent as possible with the assembly drawings, and the graphics should be clear.
　　　　　　②The dimensioning requirements are unified, centralized, orderly and complete. The order of dimensioning is: first mark the main part dimensions and the draft angle, then mark the matching dimensions, and then mark all the dimensions. Mark the mating dimensions first on the non-main parts drawings, and then mark all the dimensions.
　　　　　　③Surface roughness. Mark the most used roughness on the upper right corner of the drawing, such as "Remaining 3.2." Other roughness symbols are marked on each surface of the part.
　　　　　　④Other content, such as part name, mold drawing number, material designation, heat treatment and hardness requirements, surface treatment, graphic ratio, free size processing accuracy, technical description, etc. must be filled in correctly.
　　　　D, proofreading, trial plan, drawings, and sent to drying
　　　　　　the content of self-calibration is:
　　　　　　① molds and parts and plastic parts drawings relationship, the mold and mold parts of the material, hardness, dimensional accuracy, structure meets the requirements of plastic parts drawings .
　　　　　　② plastic parts aspect
　　　　　　　flowing stream of plastic, shrinkage, weld marks, cracks, and the like affect the slope of the release requirements of the performance of plastic parts, the dimensional accuracy, surface quality. Whether the pattern design is insufficient, whether the processing is simple, and whether the shrinkage of the molding material is selected correctly.
　　　　　　③ molding apparatus aspect
　　　　　　　injection amount, injection pressure, clamping force enough, the mold mounting, South core of plastic parts, the issue of whether the release, the injector nozzle is in contact with muzzle Xiao correctly.
　　　　　　④The mold structure
　　　　　　　a. Whether the position of the parting surface and the precision of the finishing process meet the requirements, whether there will be overflow, and whether the plastic parts can be guaranteed to stay on the side of the mold with the ejector device after the mold is opened.
　　　　　　　b. Whether the demoulding method is correct, whether the size, position and quantity of the promotion rod and push tube are appropriate, whether the push plate will be jammed by the core, and will it cause scratches on the molded parts.
　　　　　　　c. Regulating mold temperature. The power and quantity of the heater; whether the location, size and quantity of the flow line of the cooling medium are appropriate.
　　　　　　　d. The method of handling the undercut of plastic parts, and whether the mechanism for removing the undercut is appropriate, such as whether the slider and the push rod in the inclined guide column core pulling mechanism interfere with each other.
　　　　　　　e. Whether the position and size of the pouring and exhaust system are appropriate.
　　　　　　　f. Design drawings
　　　　　　　g. Whether the placement of each mold part on the assembly drawing is appropriate, whether it is clearly expressed, whether there are omissions
　　　　　　　h. The part number, name, production quantity, internal production or outsourcing of the parts on the part drawing are standard parts Whether it is a non-standard part, the matching processing accuracy of the parts, the correction processing and margin at the high-precision size of the molded plastic parts, the material, heat treatment, surface treatment, and surface finishing degree of the mold parts are marked and clearly described.
　　　　　　⑤Working dimensions and matching dimensions of main parts and forming parts. The size figures should be correct and do not cause the manufacturer to convert.
　　　　　　⑥Check the view positions of all parts drawings and assembly drawings, whether the projection is correct, whether the drawing method meets the drawing national standard, and whether there is any missing size.
　　　　　　⑦ check processing performance :( geometry of all parts, view painting, standard size 'and so whether it is conducive processing)
　　　　　　⑧ retry the main work of the size of the auxiliary tool
　
　　　　　　on the principle of professional proofreading proofreading projects carried out by the designers themselves; but to focus In terms of structural principles, process performance and operational safety. When drawing a picture, you must first digest the figure, draw according to the requirements of the national standard, and fill in all the rules
Inch and technical requirements. Self-study and sign after scanning. Submit the sketched base map to the designer for proofreading and signing. The customary practice is to have the relevant technical personnel of the tool manufacturing unit review, countersign and check the manufacturing process, and then send it out.
　　　　　　⑨ card manufacturing process to prepare
　
　　　　　　written by the card manufacturing process tool manufacturing units and technical personnel, and ready for manufacturing. In the manufacturing process of mold parts, inspection should be strengthened, and the focus of inspection should be on dimensional accuracy. Mold set
after the installation is complete, conducted by the inspector. The mold inspection checklist, the main mold parts to test the performance situation is good, the only way to manufacturing quality slang mold.
　　⑶ repair mode and test mode
　　　Although the selected molding material, molding apparatus, mold design envisioned under process conditions, but awareness are often imperfect, and therefore must be completed after the mold, mold test trial , Depends on the quality of the molded parts. After discovering that it is always the case, repair the model to eliminate errors.
　
　　There are many types of undesirable phenomena in plastic parts, and the reasons are also very complicated. There are reasons for molds and process conditions, and the two are often intertwined. Before repairing the mold, according to
the actual situation of the undesirable phenomenon of the plastic part, a detailed analysis and research should be carried out, and the remedy method should be proposed after finding the cause of the defect of the plastic part. Because the molding conditions easy to change, so the general practice is to change the molding conditions, molding conditions when the change can not be solved
when deciding the issue before considering repair mold.
　　　Repair molds should be more cautious, and do not act rashly if you are not sure. The reason is that once the mold conditions are changed, major modifications and restorations cannot be made.
Six, collating information archive
　　mold after the test, when not in use, should be completely erased release waste, dust, oil, etc., or coated with butter oil or other rust rust inhibitor, a storage area off to storage.
　
　From the beginning of the design of the mold until the mold is successfully processed and passed the inspection, the technical data generated during this period, such as the task book, the part drawing, the technical specification, the mold assembly drawing, the mold part drawing, the base drawing, and the mold design description
The specifications, inspection records, trial mold repair records, etc. shall be systematically sorted, bound, numbered and archived in accordance with regulations. This seems very troublesome, but it is very useful for repairing the mold in the future and designing a new mold.