Release time:2023-02-26 17:46Visit:
1、 Draw mold drawing
It is required to draw according to the national drawing standards, but it is also required to combine the factory standard and the factory custom drawing method not specified by the state. Before drawing the general assembly drawing of the mold, the process drawing should be drawn, and should meet the requirements of the part drawing and process data. The size guaranteed by the next process shall be marked with "process size" on the drawing. If there is no other machining besides burr repair after forming, the process drawing is the same as the part drawing. It is better to mark the part number, name, material, material shrinkage, drawing scale, etc. under the process drawing. Usually, the process drawing is on the mold assembly drawing.
1. Draw the general assembly structure diagram
The general assembly drawing shall be drawn at the scale of 1:1 as far as possible, starting from the cavity, and the main view and other views shall be drawn at the same time. (1) The general assembly drawing of the mold shall include the following contents: 1: Structure of mold forming part
2: Structural form of pouring system and exhaust system.
3: Parting surface and parting mode.
4: The overall structure and the position of all connecting parts, positioning and guiding parts.
5: Mark the cavity height dimension (not required, as required) and the overall dimension of the mold.
6: Auxiliary tools (mold removal tools, correction tools, etc.).
7: Number all parts in sequence and fill in the list.
8: Mark technical requirements and instructions.
(2) The technical requirements of the mold assembly drawing include:
1: Performance requirements for some systems of moulds. For example, assembly requirements for ejection system and slider core-pulling structure.
2: Requirements for mold assembly process. For example, after the mold is assembled, the fitting clearance of the parting surface should not be greater than the parallelism requirements of the upper and lower parts of the mold, and the size determined by the assembly and the requirements for the size should be pointed out.
3. Mold use, assembly and disassembly methods.
4. Requirements for anti-oxidation treatment, mold number, lettering, marking, oil seal, storage, etc.
5: Requirements for mold test and inspection.
（3）. Draw all parts
The sequence of drawing part drawings from the general assembly drawing of the mold should be: first inside then outside, first complex then simple, first forming parts, then structural parts.
1: Graphic requirements: be sure to draw according to the scale and allow zooming in or 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 read and easy to assemble, the graphics should be consistent with the general assembly drawing as much as possible, and the graphics should be clear.
2: The dimensions shall be unified, centralized, orderly and complete. The order of dimensioning is: first mark the dimensions of the main parts and the die angle, then mark the fit dimensions, and then mark all dimensions. Mark the fit dimension first and then all dimensions on the drawing of non-main parts.
3: Surface roughness. Mark the most widely used roughness on the upper right corner of the drawing, such as "Other 3.2." Other roughness symbols are marked on each surface of the part.
4. Other contents, such as part name, mold drawing number, material grade, heat treatment and hardness requirements, surface treatment, graphic scale, machining accuracy of free size, technical description, etc., shall be filled in correctly.
2、 Check, review, trace and print
(1) Relationship between mold and its parts and plastic part drawings
Whether the material, hardness, dimensional accuracy and structure of the mold and mold parts meet the requirements of the plastic part drawing.
(2) Plastic parts
Whether the flow of plastic material flow, shrinkage hole, weld line, crack, and release angle affect the requirements of plastic parts in terms of service performance, dimensional accuracy, surface quality, etc. Whether the pattern design is insufficient, whether the processing is simple, and whether the shrinkage rate of the molding material is selected correctly.
(3) Forming equipment
Whether the injection volume, injection pressure and mold locking force are enough, whether there is any problem with the installation of the mold, the south core of the plastic parts, and the demoulding, and whether the nozzle of the injection machine is in correct contact with the nozzle sleeve.
(4) Mold structure
1: Whether the position of the parting surface and the precision of finish machining meet the needs, whether there will be overflow, and whether the plastic parts can be left on the side of the mold with ejection device after mold opening.
2: 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 stuck by the core, and whether the formed parts will be scratched.
3: Mold temperature regulation. Power and quantity of heater; Whether the flow line position, size and quantity of cooling medium are appropriate.
4: How to handle the side concave of plastic parts, and whether the mechanism for removing the side concave is appropriate, such as whether the slide block and the push rod in the core pulling mechanism of the inclined guide pillar interfere with each other.
5: Whether the position and size of the pouring and exhaust system are appropriate.
(5) Design drawings
1: Whether the placement position of each mold part on the assembly drawing is appropriate, whether the representation is clear, and whether there is any omission
2: Whether the part number, name, manufacturing quantity, parts manufactured internally or externally, standard parts or non-standard parts, part matching processing accuracy, correction processing and allowance at high-precision dimension of molded plastic parts, and whether the material, heat treatment, surface treatment and surface finish degree of mold parts are clearly marked and described.
: 3: Working dimensions and fitting dimensions of main parts and formed parts. The size figures should be correct and should not be converted by the producer.
4: Check the view position of all part drawings and general assembly drawings, whether the projection is correct, whether the drawing conforms to the drawing national standard, and whether there are missing dimensions.
(6) Check machining performance
Whether the geometric structure, view drawing and dimension mark of all parts are conducive to processing
(7) Main working dimensions of recalculation auxiliary tools
1: In principle, professional proofreading is carried out according to the designer's self-proofreading project; However, it should focus on the structural principle, process performance and operation safety.
2: When drawing, first digest the figure, draw it according to the requirements of the national standard, and fill in all dimensions and technical requirements. After tracing, self-check and sign.
3: Submit the traced base drawing to the designer for proofreading and signature. It is customary for the relevant technical personnel of the tool manufacturing unit to review, countersign and check the manufacturing process before sending it to the sun.
(8) Prepare manufacturing process card
1: The technician of the tool manufacturing unit shall prepare the manufacturing process card and prepare for processing and manufacturing.
2: In the manufacturing process of mold parts, the inspection should be strengthened, and the inspection should focus on the dimensional accuracy. After the mold assembly is completed, the inspector shall carry out inspection according to the mold inspection table, mainly to check whether the performance of the mold parts is good, only in this way can the manufacturing quality of the mold be guaranteed.
3、 Mold test and repair
Although mold design is carried out under the expected technological conditions when selecting molding materials and molding equipment, people's understanding is often incomplete. Therefore, mold test must be carried out after mold processing to see the quality of the molded parts. After finding out that it is always wrong, repair the mold.
There are many kinds of undesirable phenomena in plastic parts, and the reasons are also very complex. There are reasons for mold and process conditions, and the two are often mixed together. Before mold repair, it is necessary to carefully analyze and study the defects of plastic parts according to the actual situation, find out the causes of defects of plastic parts and propose remedial measures. Because the forming conditions are easy to change, the general practice is to change the forming conditions first. When the problem cannot be solved by changing the forming conditions, the mold repair can be considered.
It is more prudent to repair the mold, and do not act rashly if you are not sure. The reason is that once the mold conditions are changed, it can no longer be changed and restored.
Whether the performance of parts is good or not is the only way to slang the manufacturing quality of molds.
4、 Sort out data for filing
After the test, if the mold is not used for the time being, it should be completely cleaned of demoulding slag, dust, oil stain, etc., coated with butter or other anti-rust oil or anti-rust agent, and closed to the storage place for safekeeping.
The technical data generated during the period from the design of the mold to the successful processing and inspection of the mold, such as the task specification, the part drawing, the technical specification, the mold assembly drawing, the mold part drawing, the base drawing, the mold design specification, the inspection record form, the mold repair record, etc., shall be systematically sorted, bound, numbered and filed according to the regulations. It seems very troublesome to do this, but it is very useful for repairing moulds and designing new moulds in the future.
