What is the basic design procedure of injection mold?
Injection mold design and the design of other mechanical, generally go through five stages, research information, the overall scheme design, technical design, write, technical documents, such as mold manufacturing and identification.
(1) research and capital collection
After the acceptance of the mold design task, the task requirements are clarified and the corresponding analysis is carried out.
It is the main basis for mold design to analyze the situation of plastic parts.It should be deeply discussed, understand the use of plastic parts, and analyze the technical requirements of plastic parts such as technology and dimension precision.Such as the surface shape, color and transparency of plastic parts, performance and requirements;Geometric structure, incline and insert of plastic parts;The possibility and allowable degree of forming defects such as welding mark and shrinkage hole;Position of gate, top bar, etc.;There is no coating, plating, drilling and other post-processing.The above situation has corresponding requirements for plastic parts.
Understand the physical and chemical properties, forming characteristics and process parameters of the plastics used, such as the necessary strength, rigidity and elasticity of the plastic parts.The crystallinity, fluidity and thermal stability of the plastics used;Material density and viscosity properties, shrinkage rate, specific heat and thermal deformation temperature, molding temperature, molding pressure, molding cycle, etc., they are related to the mold design, required to possess such information as far as possible, and careful analysis.
(3) gather information advanced technology at home and abroad advanced technology, often can bring huge economic benefits, therefore, should be timely collection of this kind of mold design at home and abroad advanced technology information, after the digestion of the transplanted in to the mold design.
To be familiar with the situation of the factory, it is necessary to have a good understanding of the situation of the manufacturer responsible for making and accepting the molds.The equipment capacity, technical level and production conditions of the manufacturer should be fully understood.To use the molding equipment of the factory, the technical level of workers, etc.Especially for especially to pay attention to the choice of molding equipment, for mold and molding machine is used, generally is designed according to the molding machine mold, this you need to understand the mold with the amount of injection molding machine, clamping force, injection force, mould installation size, ejection way and the distance, the size of the nozzle diameter, positioning hole, mould maximum and minimum thickness, templates, travel, etc., these data will influence the structure of the mould.
(2) overall scheme design
The overall scheme design is good or bad, and whether there is innovation in the shadow design of the die technology depends on the work at this stage.If the overall plan is flawed, it will be difficult to make a fundamental difference even if it is later remedied.The general procedure is as follows.
For a mould with plastic parts, the die structure can be many kinds.At this point, we should open up our minds and determine several mold structure plans from different angles.
(2) the analysis and comparison The advantages and disadvantages of each scheme, should carry on the comprehensive analysis and comparison, can generally from the forming position, cavity arrangement, parting surface, gating system, demoulding, mold temperature adjustment, the respect such as supporting and connecting to the specific analysis and comparison of data to quantify trade-offs.
As you work on the mold design of a plastic part, you need to finalize a design plan.Ideal mould overall plan, should be able to give full play to the ability of the injection molding machine, the work of mold itself can maximum limit satisfy the requirement of the plastic parts processing technology and economic production requirements, thus to determine a practical die structure scheme.
(3) technical design
Once the overall design scheme is determined, it shall not change at will, and it can enter the stage of human technical design, mainly including the following contents.
Drawing general assembly drawing general assembly drawing general assembly drawing general assembly drawing design is more complex, impossible a success.Generally, the sketch should be drawn first. The sketch design process is the process of designing, drawing and modifying.You can't expect all the structural dimensions to be correct at one time.In the design process, it often needs to be repeatedly modified to improve it gradually.The basic approach is to concretize the definite structural scheme in the design, starting from the cavity, from the inside out, and the main view and the top view and the side view simultaneously.
After the drawing of the general assembly sketch, the formal drawings can be drawn in accordance with the drawing standards after the inspection and verification.At this time, technical requirements and instructions should be marked on the drawing, including performance requirements of some systems, assembly process requirements, matters needing attention to use and disassembly, etc.
The drawing of work drawings of the parts in accordance with the structure in the general assembly drawing.On the parts working drawing must be detailed parts geometry size, the size of the symbol and tolerance value, surface roughness and form a demands and tolerance, heat treatment, surface treatment requirement, material type, part number, etc.The number of the part drawing shall be consistent with the serial number on the final assembly drawing.
(4) prepare technical documents
The technical documents mainly include: design specifications, operating specifications, various schedules, etc.
The design specification is the most important technical document for die design.Mainly includes: analysis and used plastic molding characteristics and process parameters, equipment selection, design of gating system, molding parts design and calculation, and demoulding mechanism design, the design of side core-pulling mechanism, the design of clamping guide mechanism, the temperature control system design, the supporting and connecting parts selection and design, etc.In the design manual, want to undertake a variety of related calculation, the calculation procedures, reference charts, formulas and data shall be listed one by one, all should make corresponding to all kinds of design diagram.
The instructions to users are prepared for the purpose, application scope, structure description, installation method, lubrication, use and maintenance of the molds.In a word, the user should be able to properly install, use and maintain this set of injection mold by referring to the user manual.
The parts of various schedules in the mold are mainly divided into three categories: workpiece, standard parts and purchased parts. In order to facilitate the search, it is necessary to make three tables to show the above three types of parts.
When writing technical documents, we should make sure that the words are concise and smooth, the writing is neat and clear, the calculation is complete and correct, and draw a brief structural diagram related to design calculation.The calculation part only needs to list the formula, substitute the data and calculate the result. The calculation process can be omitted and finally bound into a book.
(5) mold manufacturing and identification
Mould design delivery after construction, the designers to track the whole process of mould processing and manufacturing, in a timely manner to understand the progress of mould manufacturing, solve the problems in manufacturing process, change the design is not reasonable, for can not meet the requirement of the mould parts local force what work place for accommodation in the mold assembly should focus on more, when can pay attention to the mold assembly according to design requirements.
After the completion of mold assembly, the mold can be installed on the injection molding machine, and then the test model can be carried out. Until the stable and qualified injection products can be produced, the mold design can be completed.