Summary of many years of injection mold design experience

I am engaged in injection molding processing mold structure design, the previous design of household appliances, cars, electronic devices product class mold. The design level is not necessarily very high, only the work done more than more mixed just. Today happens to have nothing to do, with the big guys together to discuss the injection molding processing mold structure design problems.


First of all, after we get a product, first do not have to rush to sub-mold, the most important thing is to first check the product structure, including pulling mold, thin and thick rubber, and plastic products type problems. Naturally, this kind of for a soon to practice mold structure design people may be more difficult. Because they are likely to be unclear how to be considered more suitable for mold design with the product, this kind of nothing, only their own daily accumulation of a whole process. If you finish analyzing the product's mold pulling, wall thickness, and its area with mold release in the mold release orientation, you mostly already know the direction of the mold parting surface, and its part into the glue mouth, naturally this last or to determine with the customer.

Some people say, whether I analyze good la product structure, you can gradually design the mold, the answer is naturally NO. In order to design with half the effort, some new items about the structure of the hazard mold are to be sure. The main content is as follows.

1. the customer for the production and manufacturing of plastic machine load and type specification types, this is not well determined, you will not be able to determine the diameter of the channel of your mold into the rubber mouth set and its precise positioning circle diameter, the size of the ejector hole with the part, but also the plastic can reach into the mold deep, and even the size of the mold embryo, close the height and width ratio of these. You work hard to design a good set of mold structures with hydraulic cylinder core, you also have a sense of satisfaction, but the mold to the customer side can not be manufactured, because the customer side only has an electric plastic machine, and did not in addition to add neutrons, may then you can have a feeling of grief.

2. customer's plastic machine code mold method, generally common is the pin code mold, dowel code mold, hydraulic machine code mold, magnetic code mold. This determines a good la, you know you design the mold, or not to design the code mold dowel over the hole or code mold slot.

3. just after we analyze the product problem points, and its product clip line, product raw materials, and shrinkage rate. Do not have to subjectively feel that the PP plastic shrinkage rate must be 1.5%, this must be determined with the customer, to understand what type of raw materials they finally used to manufacture, whether they have added which modified engineering plastics these.

When there is a standard, it is best to be familiar with the product installation association and its main use of the product, this information content for the future mold construction design is very helpful.

Two people lyrics this kind of, you know what is the appearance of the surface, what is non-non appearance, what is the place of pulling the mold perspective is able to increase at will, what place is not can change. Even the structure of some products, if you understand the specific installation of the product and its main use, you will know what release structure can be removed or changed to another easy way.

Be sure to keep in mind that the whole process of making molds is the whole process of making complicated problems simple. I see people everywhere who take pride in having done a very complicated set of structures, and I think that is very foolish. Because many product technology engineers are likely to be because of their own work experience problems, design some less effective structure, if the process as a middle and lower reaches, can not help them to correct the words, they are likely to always feel that the design is nothing wrong. Then the development of everyone's product technology engineers will be very slow.

The main parameters are outside the mold water circuit, the main parameters outside the oil circuit, the main parameters outside the power circuit, the main parameters outside the air supply. Only after the design of the previous understanding of the customer such provisions, you can have the foresight to design the water channel oil channel gas supply, do not then exhaust to design a good mold, and then found that the customer must be in the mold internal series of oil channel, then you modify, maybe tired of a half-dead, because your water, small chain, screws which are always lined up a bit.

Like this four-way design, the order is generally first to ensure that the oil channel, because the oil channel to be spread throughout the balanced, specifically must be hydraulic cylinder pressure injection mold structure, if the oil channel is not balanced, the hydraulic cylinder pressure injection posture will be in order, very easy to pressure injection to unbalance. Naturally, you can also choose the transmission gear oil distributor, but that is more complicated. The next is the water circuit because the water circuit ensures the actual effect of refrigeration, all over the uneven will endanger the quality of products and mold life. The final is considered the air supply and power circuit. The order of placement on the mold is, near the TOP position is the power circuit, followed by the water circuit, the gas supply, and the bottom is the oil connection.

Other matters are not exhausted. After grasping this kind of information, you can start to design the mold. The first is the separation of the mold, this whole process may be the whole process that we all love more. Because the separation out of the mold to have a sense of satisfaction. The standard of pulling the parting surface is simple that is good, can pull Shen out of the decisive not scanner, or use other advanced instructions. The second is to have a global concept when pulling the parting surface, as simple as possible parting surface, do not have to get the seven or eight, not fine mold, these 0.1 to 0.5 of the insertion through the bit can prevent the need to prevent. In addition, the parting surface should also follow a standard, is as far as possible along the product development trend to do. Then the parting surface will be beautiful.

Insert an aside, in the study of training three-dimensional software, must bear in mind that the basic principles of each instruction are clear, then you know when you can use which instruction. The key in many cases is not that you certainly will not use the cell phone software, just that you certainly will not be unchanged in response to the cell phone software. The same command, there will be a lot of experience in the work of a variety of methods of use, which is reflected in the UG is the most significant.

In a word, the key is the idea, not the special tool itself. In the case of making a parting surface, it is only necessary to understand that the perspective of inserting through the surface can be as large as possible, the total area of touching through the surface can be as large as possible, and the pillow bit pulled out can be as wide as possible. To consider the future of this parting surface you pull in your hands today specific molds to do out, the others production plant to undertake the flying mold of the teacher will scold you on it. If you feel not easy to be scolded, then OK, again, when the future you do get scolded, this is your work experience.

In addition to doing the parting surface is certainly to take into account the arrangement of the guide slider and the oblique guide column, because these also involve the modification of the parting surface. Typical guideway slider construction is a trigonometric correlation, this is nothing more than their own calculations can be, but to ensure that the perspective of the oblique guide column does not have to be very large, as far as possible to ensure that the following thirty degrees.

Oblique guide column using the standard is to be able to thick, do not be petty, because the oblique guide column is to bear the force. In addition, the guide slider is also divided into many genetic variations of the structure, such as uphill starting guide slider, downhill guide slider, internal pumping guide slider, hydraulic cylinder pumping, front mold guide slider, guide slider with guide slider, guide slider with the countertop, guide slider with the slant top, these, this unique structure is all flexible use of trigonometric expressions, the purpose is to better complete the product out of the mold, and the mold All normal open and close the mold posture. Guide slider calculation method of major websites is the detailed introduction, I do not here too much to explain.

The next is the slant top, slant guide column is more convenient, but the typical slant guide column perspective does not have to be very large, as far as possible, do not have to exceed 15 degrees, naturally, you have to do 20 degrees also, but the service life is difficult to ensure, and the posture will be very smooth, the actual basic principle of reference trigonometry and theoretical mechanics.

Slant guide column looks like there are many ways to evolve, for example, uphill start slant guide column, downhill road slant guide column, neck skew slant guide column, set a spell to slant small chain of large slant guide column, set spell round rod of large slant guide column, set spell hanging table of small slant top, the top block under the go slant guide column, guide slider on the go slant guide column, slant top go slant guide column, slant top with the countertop, these, this all construction is all one purpose, the use of trigonometric function The product's molding to do out.

It is easy to see how critical it is to learn trigonometric functions! So for a variety of unique structures, all people want to go out, you can fully use your imagination, no matter what the structure can go to think at will, think well, to bold design, or you have creative inventions, but after the design, must be certified under the trigonometric function of the association, is a specific simulation under the mold opening and closing mold posture, and its consideration to the next injection molding processing time will not It is easy to have any problems with these.

Speaking of which, we divide the mold into good points. The following is the ranking of the mold structure, this content is all to sort out a thousand things beforehand, according to the specific circumstances of the product, using different kinds of mold structure, for example, two-plate mold, three-plate mold, hot runner system, IMD, IML, two-color, stacked mold these.

All of the mold structure characteristics are for the better to be very good to complete the product mass production and service projects. In the use of mold embryos, we need to take into account just mentioned 4 points of common problems.

The standard of the mold is to simplify the production process, save raw materials, and facilitate the product forming, such as the exhaust pipe. You think there are particularly thin areas on the mold, must be independent paneling out, easy to remove and replace in the future. In the case of the paneling take into account the compressive strength of the paneling, process performance, and its future waterway designability. After the paneling, it is necessary to add standard parts. 

The standard of adding standard parts is the key first after the part, as far as possible layout balance symmetry. Generally, to put the top bar first, adding the top bar must take into account the arrangement of the waterway. Under general conditions, priority should be given to the arrangement of the small chain, followed by the general design of the waterway, and then adjust the waterway small chain according to the specific situation, so that the two can be balanced. The standard of adding pressure shot is the area of high clamping force, in addition to the flute, table, side of the product, such as the compressive strength structure of the better area, to prevent top white or unbalanced pressure shot. The standard of the drainage road is the standard of the pressure shot, because generally speaking, the area of the product with high clamping force is also the hot spot of the product's network, which must be elevated to the position of refrigeration, and this difference must be adjusted.

For in the end is a small chain or with the top block or push plate, it must be the actual problem in-depth analysis. This to integrate the structural characteristics of the product to analyze, for example, the product is very easy to stick to the front mold, it is necessary to consider the need for the rear mold plus demoulding, or the front mold plus ejector, this is all logical thing, but many basin friends are not easy to think about the full range of what is going on, that or because there is no product structure features sufficient, no specific consideration of the next product in the injection molding process throughout the process. It is the importance of the puzzle. The small chain of waterway added full, the remaining is these messy standard parts, the big guys in the case of adding as much as possible to take into account the symmetry of the balance is.

After the full set of mold designs, be sure to do the following types of checks, the first is the mold pulling analysis of the insert, to see if there are areas of mold release, followed by the mold parts of the intervention checks, the top priority. Today's three-dimensional software is to have this role, convenient very. Subsequently is the mold open and close the mold posture simulation, and then simple mold if they are not too clear, they must be a specific simulation, in addition to the mold parts can be process performance and its mold installation process, don't work hard to design a proper structure, the basic theoretical calculations are not much problem, after the production and processing, the results can not be installed, or not very good installation.

At this point, I can congratulate you, the general steps have long been over. In fact, mold design is a matter filled with differences. Want to design some extreme, the mold cost is high, want to design some simple, it is likely that the product will need to change or mold compressive strength, the use of the period will have an impact. Therefore, the mold design is not sure.

If you look for a good balance, the mold you design is a success. Therefore, the structure designed by others may not always be suitable for you. If you follow the above key points of mold design, you may be able to design a more effective mold structure.