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viscosity curve injection molding 주제에 대한 동영상 보기
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This video shows a Viscosity curve \u0026 how to set up a graph to tell you what speed to use. I hope this helps, I am not very good of explaining how to do this. I always start low \u0026 bring the speed up slowly till I have the part almost full. I do appreciate everyone’s support \u0026 help to the channel.
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The Importance of Viscosity Curve Injection Molding
The plastic flow curve shows how much material will be injected. The scale changes from the highest point to the lowest point depending on the …
Source: pro-plastics.com
Date Published: 2/12/2021
View: 4738
GeneratingViscosityCurve – Injection Molding Online
The figure below shows a typical viscosity curve that as generated at the molding machine. How to use this information: Looking at the above curve, one can …
Source: injectionmoldingonline.com
Date Published: 5/3/2022
View: 9400
How to define the viscosity curve of injection molding?
How to define the viscosity curve of injection molding? … 1) Set the melt temperature in mdle of range a described by manufacture. 2) Set all the holding …
Source: www.acomold.com
Date Published: 4/18/2022
View: 8406
(IR)Relative Viscosity – Trouble with the Curve
The Relative Viscosity (RV) test is often used to help entify an eal fill speed/time for the mold. Fill speed and the resulting fill …
Source: www.beaumontinc.com
Date Published: 12/4/2021
View: 1442
Viscosity Curve (inmould viscosity) – Udemy
… plastics process technology injection moulding and need to optimise processes. Practice informs practice Module 01. Viscosity Curve (inmould viscosity).
Source: www.udemy.com
Date Published: 4/24/2021
View: 926
What Is Viscosity and How to Monitor It in Injection Molding …
Viscosity is a flu’s resistance to flow, or the amount of friction that exists in the material. The higher the viscosity, the more friction …
Source: rjginc.com
Date Published: 12/7/2022
View: 2623
주제와 관련된 이미지 viscosity curve injection molding
주제와 관련된 더 많은 사진을 참조하십시오 Viscosity Curve. 댓글에서 더 많은 관련 이미지를 보거나 필요한 경우 더 많은 관련 기사를 볼 수 있습니다.
주제에 대한 기사 평가 viscosity curve injection molding
- Author: Injection Molding Skills \u0026 More
- Views: 조회수 456회
- Likes: 좋아요 17개
- Date Published: 2021. 11. 1.
- Video Url link: https://www.youtube.com/watch?v=-0rGauI4RkU
What is viscosity curve in injection molding?
The viscosity curve is a plot of the polymer viscosity vs. shear rate. Data is plotted here on linear scales rather than the log-log method. Interpreting this data will guide you to an appropriate fill time for this particular mold and resin.
What is a viscosity curve?
A flow curve – also known as a rheogram – is a graphical representation of how a flowing material (fluid) behaves when it is subjected to increasing or decreasing shear rates. The corresponding shear stress and viscosity are calculated from the instrument’s parameters.
What is viscosity in plastics?
What is viscosity in a plastic? Viscosity is the resistance to flow that the plastic faces when it is melted, ie if the plastic is too viscous it has difficulty draining through the nozzle of the injector or die of the extruder, as opposed to a plastic of low viscosity that will drain easily.
Why viscosity is important in plastic manufacturing process?
In a very simplified definition, viscosity is the resistance to flow. Why does viscosity matter for materials? In general terms, polymers are injection molded, compression molded, or extruded– all of which require forcing a polymer into a shape. Therefore, viscosity is especially important for polymer processing.
What is shear rate in fluids?
Shear rate is the rate at which a fluid is sheared or “worked” during flow. In more technical terms, it is the rate at which fluid layers or laminae move past each other. Shear rate is determined by both the geometry and speed of the flow.
What are types of viscosity?
Viscosity Types
There are two ways to measure the fluid’s viscosity as follows: Dynamic Viscosity (Absolute Viscosity) Kinematic Viscosity.
How does a viscometer work?
This type of viscometer uses a rotating apparatus, known as a spindle, which you submerge within the fluid you are testing. The torque on the rotating shaft of the spindle will then measure the fluid’s resistance to flow. The rotational viscometer measures the absolute viscosity of the fluid.
What is the units of viscosity?
The unit of viscosity is newton-second per square metre, which is usually expressed as pascal-second in SI units.
What is rheology curve?
Rheology. In order to determine the general flow behaviour of a sample the viscosity is measured as a function of the shear rate in a rotational rheometer. For the presentation of the data either the viscosity or the shear stress is plotted against the shear rate. The thus obtained graph is called flow curve.
What is flow curve?
A flow curve is a graphical representation of how the shear viscosity of a sample changes when it is subjected to different shear rates or shear stresses.
How is plastic viscosity determined?
Trenchlesspedia Explains Plastic Viscosity (PV)
To reduce PV, the solid contents can be reduced by diluting the mud. PV is measured using a viscometer by measuring the shear rate at 600, 300, 200, 100, 6 and 3 rounds per minute (rpm). PV value is obtained by subtracting the 600 rpm reading from the 300 rpm reading.
How is plastic viscosity calculated?
The plastic viscosity (PV) of the drilling fluid is calculated by subtracting the 300-rpm shear stress (R300) from the 600-rpm shear stress (R600). The yield point of the drilling fluid (YP) is calculated by subtracting the PV from the R300 reading. Multiplying the rpm by 1.7 changes the units to re- ciprocal seconds.
What’s the difference between plastic and viscosity?
Answer: Plastics, which are non-newtonian solids, can and do flow as a liquid, relative to outside forces. … For a Newtonian fluid, the apparent viscosity is constant, and equal to the Newtonian viscosity of the fluid, but for non-Newtonian fluids, the apparent viscosity depends on the shear rate.
What is mean by flow curve?
A flow curve is a graphical representation of how the shear viscosity of a sample changes when it is subjected to different shear rates or shear stresses.
What is rheology curve?
Rheology. In order to determine the general flow behaviour of a sample the viscosity is measured as a function of the shear rate in a rotational rheometer. For the presentation of the data either the viscosity or the shear stress is plotted against the shear rate. The thus obtained graph is called flow curve.
What is viscosity of water?
The viscosity of water at a temperature of 20 degrees Celsius is roughly equal to 0.01 poise or 10–3 Pa. s (Pascal seconds). Alternately, this value can be represented as 1.0016 mPa.
What is Rheogram in pharmacy?
Rheology is the science of flow and deformation of matter. Particularly gels and non-Newtonian fluids, which exhibit complex flow behavior, are frequently encountered in pharmaceutical engineering and manufacturing, or when dealing with various in vivo fluids.
What are Viscosity Flow Curves?
What are Viscosity Flow Curves?
A flow curve – also known as a rheogram – is a graphical representation of how a flowing material (fluid) behaves when it is subjected to increasing or decreasing shear rates. The corresponding shear stress and viscosity are calculated from the instrument’s parameters. You can tell what type of fluid (Newtonian/Non-Newtonian, thixotropic, dilatant, etc.) the sample is by the shape of the flow curve.
It is essential to know the fluid type and understand the flow curve so that you can make sure your product will be suited to its applications. For example, say that you have toothpaste that you need to pump through a tube. You’ll need to make sure that the toothpaste is shear thinning. That is, the force required to pump the toothpaste through the tube will make the fluid less viscous, and therefore it will flow more easily through the tube.
Creating a flow curve involves testing a sample over a range of shear rates. It’s most useful to make the testing parameters relative to how the sample will be processed in manufacturing or how the consumer will use it.
How to Create a Flow Curve:
Decide what you want to test. Determine your testing parameters. Prepare a chart to document the test results. Program and run the test, recording the results in your chart. Create a graph based on the results in the chart.
Here’s an example:
(1) Let’s say you make toothpaste and you want to make sure it will flow easily when the user squeezes the tube, but won’t leak out when the tube is not being squeezed.
(2) You decide that you want to test your product at room temperature, starting at 0 rpm and gradually ramping up the speed. At a certain point, you will gradually lower the speed back to zero.
(3) You create an Excel spreadsheet to log the viscosity and shear rate (rpm) results.
(4) Program and run the test, recording your results every time the speed ramps up, and again when it ramps down.
(5) Use Excel to create a graph from your chart.
Common Terms Associated with Flow Curves: Yield Stress and Zero Shear Viscosity – What Do They Mean?
Yield Stress is the force needed to initiate flow of fluids that do not flow when they are stationary. This type of fluid is called “plastic”. You can see yield stress in your testing if the viscosity of your product increases as the shear rate decreases to zero.
Zero Shear Viscosity is a term for non-plastic fluids. With this term, the viscosity of the fluid will plateau as the shear rate decreases to zero. This indicates that the fluid flows like a liquid when stationary.
Got questions about flow curves? Know of any good resources that explain this concept? Leave us a comment below!
Until next time,
Amanda
P.S. Be the first to know when we post a new blog article by subscribing at the top of the page!
Fluidity and Viscosity
Bibliography:
HARPER, Charles A.; PETRIE, Edward M. Plastics Materials and Process: A Concise Encyclopedia. Hoboken: John Wiley & Sons, Inc., 2003.
CANEVAROLO JR., Sebastião V. Ciência dos Polímeros: Um texto básico para tecnólogos e engenheiros. 2.ed. São Paulo: Artliber Editora, 2002.
WIEBECK, Hélio; HARADA, Júlio. Plásticos de Engenharia: Tecnologia e Aplicações. São Paulo: Artliber Editora, 2005.
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A very important property for choosing a particular thermoplastic is the melt flow index, especially in the case of polyolefins and styrene. The higher the flow rate, the lower the viscosity of the polymer and vice versa.Viscosity is the resistance to flow that the plastic faces when it is melted, ie if the plastic is too viscous it has difficulty draining through the nozzle of the injector or die of the extruder, as opposed to a plastic of low viscosity that will drain easily.A simple example is to compare honey with water. The honey flows with difficulty, therefore it is viscous and consequently it has low fluidity. The water flows very easily, therefore it has low viscosity and consequently high fluidity.The melt flow index in practiceThe melt flow index (MFI) is verified in a device called plastometer, common in petrochemical laboratories and plastics recyclers. The result of this analysis is used for quality control and as a guideline for the process in which the plastic will be destined, with polymers with low melt flow being used in extrusion processes, while the medium and high are directed to injection molding.The laboratory test does not accurately reflect what occurs during processing in a plastic injector, for example. This happens because inside the plastometer channel there is not the same shear that occurs inside the barrel of the injector, just as the plastometer has no screw but a piston; and its channel is vertical, unlike the horizontal injector. Besides those that I mentioned there are infinite variables …What I mean by that is that there is not much difference between resins with 38, 39 and 40 MFI, for example; but there is a lot of difference between resins with a MFI between 3 and 40. In the case of recycled, the MFI is very important to verify the uniformity of the batches, because if one batch presents fluidity 10 and the other 20 it means that there were big changes In the raw material used, which may cause some changes in process parameters of the transformer.The table below shows the relationship between the melt flow index and the different transformation processes for PE and PP . Blue cells indicate adequate fluidity for each process:You can do both, but there are no miracles in the world of plastic …Well, to increase fluidity, nucleating agents and lubricants such as molybdenum disulfide or PTFE are used. Talc, for example, works as a nucleating agent when in proportions less than 10%, slightly increasing the flowability. But when in larger proportions than this can promote opposite effect, as well as other loads (glass fiber, polybutadiene, TPU , and etc.).A common misunderstanding when reading the MFI in a datasheet is not paying attention to the method that was used in the test. Let’s see the example below:This is a part of the technical data sheet for Terluran GP-35, Basf’s famous high-flow ABS, where the results of flow tests are presented in three different test methods:* Plastometer at 230°C and 3.8kg of load* Plastometer at 220°C and 10kg of load* Plastometer at 200°C and 5kg of loadThe result in each of the tests was 11, 34, and 3.1, respectively.If you use this material, you called a piggy dealer asking for a alternative resin of 11 MFI, and they sent you one of 11 MFI by the 10kg method, I’m sorry to say you screwed up…And as in the plastics world, “there are always complications”, there are two ways to do the test: measuring the melt flow rate with the result in g / 10min, and measuring the volumetric flow rate with the result in cm³ / 10min as in the case above. The difference between the results of the two forms is not very significant for most thermoplastics, since they have a density close to 1g / cm³, but we must pay attention to denser materials such as polyacetal
The Importance of Viscosity Curve Injection Molding
The Importance of Viscosity Curve Injection Molding
The plastic flow curve shows how much material will be injected. The scale changes from the highest point to the lowest point depending on the fill time. This can help ensure consistency when making parts. The best data will show the same shape. When using the viscosity curve, remember to balance the fill time with other components of the part. If the process is too complicated, you can reduce the amount of plastic and increase the speed.
The viscosity curve is determined by testing multiple settings of injection speed. The process is scientific and is based on calculations of the plastic pressure at transfer. Using the results of the study, you can design a mold with a desired shape and size. The best way to achieve consistency is to choose the correct fill time. Then, you can adjust the speeds accordingly. For a particular mold, you can add or remove heat to reduce the viscosity.
Another important aspect of viscosity curve injection molding is the fill time. This affects the mold’s filling speed. The molding machine creates the viscosity curve for a specific material. A non-Newtonian shear rate causes the material’s viscosity to shift drastically. Changing the fill time can result in inconsistency and poor quality parts. You must have a solid grasp of the flow control of the mold to make the process run smoothly.
Injecting resin and plastic using a viscosity curve helps you understand how the plastic will react to different viscosities. It allows you to control the speed of the injection. The injection speed should be adjusted to suit the type of material. Increasing the speed will increase the filling time, thus increasing the injection time. The process will not produce a large amount of waste in the end. This makes the viscosity curve in the plastic more reliable and durable.
A good viscosity curve will allow you to determine the best fill time for your part. Injection speed is determined by a combination of temperature, shear rate, and resin thickness. This is the most important factor in the fill time. If your parts are filled at the right time, they will be perfectly molded. So, it’s crucial to select the right temperature and fill speed for your material. It will help you determine how much plastic you need to produce.
The viscosity curve is the measurement of the plastic’s viscosity with the right speed and pressure. It is an essential part of the mold’s design. During the mold’s manufacturing process, your plastic should be consistent in the fill time. This process has several steps. The first step is to record the maximum volume in each cavity. Then, you should measure the fill rate of the entire piece with the other side of the same mold.
Once you have the desired viscosity, you can start the molding process. The viscosity curve is an essential part of the process. It is a way to monitor the material’s flow and avoid possible defects. This is a very important step in the molding process. If you are using the proper mold, it will help you avoid part defects. If the part is damaged, it will require additional work.
When molding a part, you must evaluate its viscosity. If the part does not fill properly, you should try to remove it. Then, you should test the part again. After the mold has been removed from the mold, you should test it to make sure that the mold works in the correct condition. The injection speed profile is an important factor in molding. The machine’s accuracy depends on the viscosity.
To increase the consistency of your parts, you can use the viscosity curve. The viscosity curve is a useful tool in the injection molding process. By utilizing this tool, you can test the material’s viscosity and how it will affect the part’s quality. You can also test the part’s consistency by testing its consistency. It is very important to make sure the part’s flow does not change during the mold filling.
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How to define the viscosity curve of injection molding?
How to define the viscosity curve of injection molding?
Viscosity = Peak Injection pressure* fill time * Intensification factor
1) Set the melt temperature in middle of range a described by manufacture.2) Set all the holding phase parameter to zero. This means only injection no holding.3) Set the Injection pressure to maximum to available.4) Set the cooling time sufficient to ejection.5 Set injection speed slow, and make sure component should be short only 50% filled, if not adjust the material position.6) Increase the injection speed in steps and sure that part should be still short. When injection velocity is full adjusting the material position that only 95% component is filled.7) Now make another shot and note the Fill time and peak pressure.8) Now lower the injection speed to 90%, 80% so on and note down peak pressure and fill time.9) Find the screw intensification factor of screw (for electric machine it is 1:1, for hydraulics it is Area of ram/section area of screw)10) To get viscosity use the formula.11) Plot the graph Injection speed vs Viscosity.You get the region in curve where viscosity is constant w,r,t to Injection speed . This is you region of processing for injection speed, where the consistency in maintaining shot to shot. (Now shearing at nozzle and at gate point not changed the viscosity).Sometime solution is depending on shape of the component. For example we face warpage problem in Car interior view mirror housing, As a result mirror is not assembled properly. But I did, tighten two component of housing with rubber band after produced from machine and store these as it is. These are opened on assy line when mirror is to be fitted problem is resolved.
(IR)Relative Viscosity – Trouble with the Curve %%sep% Beaumont Technologies, Inc.
The Relative Viscosity (RV) test is often used to help identify an ideal fill speed/time for the mold. Fill speed and the resulting fill time are an indication of how fast the plastic is injected into the mold. The speed affects how much shear heating and shear thinning the plastic experiences, which in turn affects the material’s viscosity, the pressure, the temperature of the plastic inside the cavities, and the overall part quality (dimensional, aesthetics, strength, etc.). Though there are many different approaches to selecting the idea point, those who teach this method generally agree that for most parts the fill time should be located somewhere on the flatter portion of the curve (Figure 1).
When researching this procedure to better understand what it is telling us, some nuances were uncovered. For example, the results are completely dependent on the scale of the graph. Also, the graph may be harder to interpret when using fewer data points because the traditional “flat” part of the curve will not look as flat as it normally would. And finally, when you graph a number versus its reciprocal (Fill Time and 1/Fill Time are in both the Y and X-axes respectively), the shape of the curve shown in Figure 1 is expected.
Interestingly, we found that when evaluating the typical RV data differently you would see a nearly straight line. From this it was theorized that we could very closely recreate the original RV curve by utilizing only two data points (“2 Point Rheology Curve”). The result was a near identical RV curve calculated by using only two data points as a reference versus the original RV curve which took twelve (12) data points to generate (Figure 2).
It was also theorized that when using the RV method and matching fill times to establish the X-axis scale that every mold would actually produce the same general RV curve. To test this theory, a RV test was run on several different molds by matching fill times as closely as possible. Figure 3 shows the overlaid RV curves from two of the test molds. As shown, the general shapes of the curves are nearly identical. This would indicate that one would more than likely select the same fill speed for both molds regardless of material, cavitation, cooling, temperatures, machine, and runner system.
There are numerous alternate approaches that are practiced and that we continue to study. One such alternative is to evaluate Pressure vs. Fill Time (Figure 4). Though certainly having its limitations, this approach provides valuable information including: a quick indication of the fill time at which the process will be close to being pressure limited, one can evaluate thermal vs. shear dominated flow transitions (U-shape part of the curve), and it is performed using simple terminology without the need for calculations. Most certainly “fill time” and “pressure” are terms that a processor is familiar with and are more easily understood and interpreted.
No matter which method you use, neither method should be the end all determining factor for setting a fill time. The molder must understand the limitations of the chosen method and adapt based on the molded part.
For additional research data and understanding, please contact our Continuing Education & Training department at 814-899-6390 ext. 131 or visit our Featured Articles page (select “Optimizing Fill Time” under Plastics Technology Magazine).
Viscosity Curve (inmould viscosity)
This lecture is for beginners and experts who are interested in plastics process technology injection moulding and need to optimise processes.
Practice informs practice Module 01
Viscosity Curve (inmould viscosity)
Introduction and Chapter 01 (public) Length 24 min 18 sec
– The history of the relative viscosity curve
– An example of the difficulties of collecting data to create a viscosity curve in the past.
– The learning objectives of this module “Setting the maximum injection speed using the relative viscosity curve”.
– What we can detect and influence in the injection phase.
– And methods of filling time determination
Chapter 02 – Length 24 min 24 sec
Topic Shear
– the influence of shear during melting
– the MFI or MFR
The apparent shear rate
Chapter 03 – length 22 min 12 sec
– The filling time
– The shear rate
– The creation of a Relative Viscosity Curve.
Chapter 04 -Length 11 min 51 sec
– The ideal relative viscosity curve
– Reference to tool optimisations and machine maintenance data (recognisable from the Relative Viscosity Curves.
Chapter 05 – Length 28 min 10 sec
– Relative viscosity curves created in practice with explanation and evaluation.
On one of the curves the possible tool optimisations and which maintenance data we can generate with the curves.
Chapter 06 – Length 07 min 52 sec
– Summary
– In the end credits we talk about our technical injection moulding technique.
Chapter 07 – length 00 min 37 sec
Questions and answers is empty in the basic version
Total time 120 MInutes
What Is Viscosity and How to Monitor It in Injection Molding Processes
A student once joked that, “9 out of 10 times when you ask a question, the answer is viscosity.” While it’s probably not quite 9 out of 10, the student did have a point. We like asking why things happen, and quite often viscosity is indeed the answer. If the viscosity of the material was either consistent or predictable, this whole injection molding thing would be easy.
If, by the student’s estimation, 90% of our issues come back to viscosity, it sure would make sense to track it. This article covers the definition and characteristics of viscosity, why it’s important to monitor viscosity, and how to measure viscosity.
What Is Viscosity?
Viscosity is a fluid’s resistance to flow, or the amount of friction that exists in the material. The higher the viscosity, the more friction that exists, so the more pressure you need to inject it into a mold.
Picture a plain chain necklace and a necklace with a lot of large beads on it. Which necklace would go down the drain easier? The plain chain, right? That’s the same idea with viscosity—with low viscosity, the molecules are lined up in a plain, simple chain. Higher viscosity means more complexity and friction (beads), so it is more difficult to inject.
Viscosity often changes from lot to lot of the same exact material. As you can imagine, a viscosity change could greatly affect how your process runs, leading to poor quality parts when nothing else has changed. Without knowing it’s viscosity, this can be quite confusing and lead to a lot of unnecessary button pushing and scrap. Or worse, shipping bad parts.
Another cause of viscosity change is plastic degradation. Plastics can degrade in different ways, one of which is polymer chain degradation, a simple breaking of the polymer chains. Two important things happen when polymer chain degradation occurs: the material becomes weaker and the viscosity lowers. There are clear part performance issues with weaker material, and lower viscosity plastic will tend to give us issues, such as out of spec dimensions or flash.
Why Is It Important to Monitor Viscosity?
If we track viscosity changes over time, we can often be alerted to problems well before quality has a chance to inspect the parts. When viscosity rises, pressure in the cavity drops, which yields smaller parts or parts with sinks and shorts. As contradictory as it may seem, higher injection pressures typically indicate lower cavity pressures.
More often than not, short shots correlate with higher viscosities, and flash correlates with lower viscosities. Figure 1 shows an example of data over time. Notice the clear correlation between viscosity and cavity pressure—molders who are already using instrumented molding are likely familiar with this correlation. Since variations in cavity pressure influence most of our issues (dimensional variation, shorts, sink, flash, warp, etc.), tracking one of its drivers is tremendously valuable.
Tracking viscosity is a vital step in solving a great deal of your molding problems. Next time a solid process turns into a headache, you won’t have to guess whether the viscosity changed, or by how much.
How Do You Measure Viscosity?
Determine Melt Flow Index
One of the most common ways of measuring viscosity is MFI, or melt flow index. The melt flow test measures how much plastic can be pushed out of a small hole in a given amount of time.
The test is very simple: plastic is put into a heated pot and then pushed out of this pot through a small hole via a piston with weights pushing on it. Each type of material should have specified temperatures and weights that are used to make the test valid. After ten minutes, the material that has been pushed out of the heated pot is weighed. This value in grams is the MFI.
Materials with lower viscosities will result in more material being pushed out of the heated pot, therefore a “16 melt” has a lower viscosity (is easier to flow) than a “12 melt”.
When a new lot of material comes in, the vendor will often specify what results that lot received from the MFI test. In our classes, we teach that we can expect up to a 20% viscosity shift in the material itself, irrespective of any damage the molder may or may not do to it. If this sounds like a large number, look at your next lot and you will see that the tolerance range on a “12 melt” material maybe as large as 7 to 15 percent, or even a bit over 20 percent!
As valuable as knowing the MFI of a particular lot is, consider that this is a very small sample (quite literally a few grams) of a tremendous amount of material—perhaps hundreds of tons. Even molders who are aware of MFI often relegate it to the realm of the material suppliers. Once the lot is out of the shipping dock, MFI becomes a forgotten concept, which is unfortunate, because the MFI test can tell us a great deal about our material.
Melt Flow Indexer Tool
A Melt Flow Indexer can be purchased for much less than the far more common moisture analyzer and can be a very helpful tool for determining if a material has degraded. It uses a weighted plunger to push plastic out of a heated pot, and although not every molder has this particular piece of equipment, they all have something very similar—an injection molding machine.
For example, if we compare the condition of the plastic in the feed throat to the condition of the plastic after it has been molded, we can determine if we are indeed degrading our material and take action to correct the situation. Although we often assume that all degradation occurs in the barrel, we can damage plastic at multiple phases of the value stream. Chemical contaminants during shipping, over drying, or exposure to UV light can all cause polymer chain degradation, and isolating the root cause is the first step in fixing the issue.
Viscosity can be thought of as how hard we are working to flow the material. If I asked you, “What is more work: moving 50 pounds, 10 feet or moving 100 pounds, 5 feet,” you could make the argument that they are both equal amounts of effort. We can use the same thought process to calculate the effective viscosity of our material. By multiplying the fill time by the injection pressure at transfer, we can approximate how hard the machine is working and for how long.
Conclusion
Determining viscosity, knowing when a material has degraded, and monitoring viscosity during the injection molding process is vital to preventing part defects before they happen, or stopping them quickly with minimal scrap. With the right tools, it’s an easy task with a huge payout.
Learn more about viscosity in our Fundamentals of Injection Molding training course.
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Viscosity #Curve
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주제에 대한 기사를 시청해 주셔서 감사합니다 Viscosity Curve | viscosity curve injection molding, 이 기사가 유용하다고 생각되면 공유하십시오, 매우 감사합니다.
