Intelligent injection process system

Intelligent injection process system

TechnologistsWorkerArtificial Intelligence
Reminiscence, using for referenceInitial process parameterCase-based reasoning
InstinctiveTrainSimplified model
Repeatedly mold testingEliminating defects of productsFuzzy reasoning
Continuously adjustingStable and efficient moldingMachine learning

The list is a Comparison of the intelligent “mold testing” process and the artificial mold testing process.

1. The system overview

The plastic injection molding process parameter intelligence system is the plastic injection molding process parameter setting and optimization system.

researched and developed by the national key laboratory of material forming and mold technology of Huazhong University of Science and Technology.

In the injection production, there are lots of complicated factors to influence the product quality, including raw material,

the injection molding machine, forming process and mold structure, etc.

after the plastic raw material, the injection molding machine and mold structure are confirmed,  it usually needs to adjust the injection molding process parameters, that is, the so-called “mold testing” process.

During the process of the traditional process of “mold testing”,

the determination method of process parameter is mainly trial-and-error method, i.e. to carry out “cut-and-try” repeatedly according to the experience of technologists and relatively simple calculation formula. 

However, as the flowing properties of plastic melt differ in thousands of ways,

the mold structure is infinite in variety, the process parameters affect each other,

it is difficult to consider and process these factors comprehensively just reply on limited experience and simple formulas.

Therefore, the length of time and the quality of “mold testing” depends on the level of technologists.

The plastic injection molding process parameter intelligence system adopts the artificial intelligence technology to simulate the “mold testing” thinking of technologists,

to conduct the process parameter setting and optimization of the plastic injection machine,

having the advantages of high success rate, simple operation and low requirements for the level of technologists, etc. 

The comparison between the “mold testing” process of the plastic injection molding process parameter intelligence system and the artificial mold testing process is shown as the list beginning.

The plastic injection molding process parameter intelligence system consists of two steps:

The setting of initial process parameters and defects amendment.

For the setting of initial process parameters, a group of process parameters will be set automatically according to material type,

mold information and the model of injection molding machine;

the defects amendment will automatically adjust process parameters according to the feedback defect type and severity of product through “mold testing” ,

and then the “mold testing” is continued till the qualified product is injected, its process structure is as shown in the list 2.

Along with the rapid development of the plastics industry and the increasingly fierce market competition,

the requirements for the production quality and production efficiency of plastic products become more and higher;

the plastic injection molding process parameter intelligence system can improve the quality of “mold testing”,

shorten the time of “mold testing” and reduce the requirements for the level of technologists.

List 2 “Mold testing” process of intelligence system
Automatically setting process parameters
Mold testing
Succeed Yes
No
Inputting the type and quantity of the defect of products
Inputting the information on mold and plastic, etc.

2. Instruction for use

2.1   “Initial” page

The injection molding machine with the module of plastic injection molding process parameter intelligence system will enter into the main screen of controller after starting up,

and after selecting the button “optimization”, it will enter into the plastic injection molding process parameter intelligence system. 

The plastic injection molding process parameter intelligence system interface consists of two pages:

“Initial” page and “Optimization” page.

After entering into the plastic injection molding process parameter intelligence system,

selecting the button “F1 Initial” and it enters into the “Initial” page.

The “Initial” page is shown as Figure 3, used for setting the information of materials and mold.

The initial process parameter page contains the information of material, mold cavity, mold, and others.

Besides, there is a button of “Initial derivation”.

After setting the information of material, mold cavity, mold and others in the page, click the button of “Initial derivation”,

the initialized process parameter can be acquired. For a pair of mold, the initial process parameters only need setting once. 

Each item of content on this page will be explained in detail as follows.

①    Material name

The material names are used to select the material type of the product,

at present, the optional material types include:

ABS, PA66, PC, HDPE, PMMA, POM, PP, PS, PVC, PA6, PBT, PET, PA12, and the default value is PP.

If the product materials are not listed, it is OK to select the materials of similar forming properties,

if you need more material information, you can contact the dealer.

②    Average wall thickness

Please input the average thickness of the product, unit: mm.

The average thickness of the product is used to describe the difficulty level for the molding of the product.

While using, you do not need to input the average thickness of the product very accurately.

③    Quantity of pouring gate

Please input the quantity of pouring gates, the quantity includes all the cavity. 

④    Runner length

Please input the farthest distance from the spray nozzle to the pouring gate, unit: mm.

Such as, in Figure 4, the length of the runner is the total length of the heavy line.

While using, you do not need to input the length of the runner very accurately.

Material nameWeight of product
Average thicknessFlowing length
Quantity of pouring gateWeight of runner
Runner lengthInitial derivation
QQ截图20170803135008.png
Figure 3 Initial process parameter page

⑤    Weight of product

Please input the estimated weight of the product (the runner part is not taken into account),

the unit is gram. You do not need to input the product weight very accurately while using,

but the more accurate product weight is inputted, the quicker the system can calculate the molding process parameters.

⑥    Flowing length

Please input the flowing length of product, unit: mm.

The flowing length refers to the longest length from the pouring gate to the extreme end that the product flows,

such as, in Figure 5, the flowing length is the total length of the heavy line. 

While using, you do not need to input the flowing length very accurately.

⑦    Weight of runner

Please input the expected weight of the runner part, unit: gram. 

You do not need to input the runner weight very accurately while using, 

but the more accurate runner weight is inputted, the quicker the system can calculate the molding process parameters.

⑧    Initial derivation

Click the button “initial derivation”,

the initialized process parameter can be acquired; the initialized process parameters can be checked in the page of “quick setting”, as shown in Figure 6.

The initialized process parameters include injection, pressure maintaining, material storing, temperature, injection and cooling time parameters.

After obtaining the initialized process parameters, the mold testing can be carried out according to these process parameters.

Please be sure to check whether your mold has been installed correctly before mold testing, and the manual mode should be adopted.

And pay attention to check whether the barrel temperature reaches the setting value.

2.2   “Optimizing” page

The plastic injection molding process parameter intelligence system can continuously adjust the process parameters according to the situation of mold testing,

to gradually calculate the molding process window and obtain appropriate process parameters thereby.

The results of the mold testing will be fed back to the intelligence system,

to input through the “optimization” page. After entering into the plastic injection molding process parameter intelligence system,

select the button “F2 optimization”, and it enters into the “optimization” page, as shown in Figure 7.

The system includes 12 kinds of common products defects in the plastic injection molding production process;

the system carries out the automatic optimization of process parameters according to the inputted defects type and severity of products.

While optimizing, multiple defects categories can be selected at the same time,

the defect degree of each kind of defect is divided into 4 kinds: None, light, normal, and serious.

Each item of content on this page will be explained in detail as follows.

①    Short shot

It is also named as the short injection, insufficient filling, incomplete product or irregular glue lying;

refers to the mold cavity is not filled completely which causes the product is not full and the shape is incomplete.

②    Shrink

It is also named as the sunken part, the sink mark or the shrinkage,

refers to the uneven surface of product, shallow pits or lacuna produced inwards.

③    Flash

It is also named as the flash, overflowing edge, rough selvage or excessive flash,

refers to the defect of plastic overflowing caused by excessive filling at the discontinued parts (usually the parting surface, gas vent, exhaust thimble, and sliding mechanism, etc.) of the mold.

④    Warping

It refers to the rotating or twisted phenomenon that appeared on the product, there is a wavy part on the flat place,

the straight edge is bent or twisted inward or outward.

⑤    Ripple

It is also named as flow mark, which refers to the wave-shaped scraggly phenomenon of growth ring shape, spiral or cloud shape.

⑥    Scorched

Scorched is also named as burnt spots, dark spots or black streaks,

it refers to the dark-colored spots or dark-colored streaks that appeared on the surface of the product.

⑦    Bubbles

It refers to the phenomenon that clusters of pore space with small volumes are formed inside the product.

⑧    Stripping

It refers to the phenomenon of layer stripping that happened on the product, just like the mica piece.

⑨    Dull color on the surface

Normally the gloss of the surface of the injection molding products is mainly determined by the type,

colorant and degree of finish on the surface of the mold. Frequently,

dull color on the surface of the product will be caused by some reasons. 

2019年9月24日 Industry News