Klarm Mould Blog

Difficulties of molding different plastics on injection molding

05/18/2019Klarm Mould

When it comes to plastic injection molding, manufacturers have a lot of problems and difficulties to deal with. Manufacturers use plastic for many reasons, such as design flexibility, affordability, and lightweight, just to name a few. Making parts and designs with injection molding has some difficulties. Let’s take a look at them.

During the injection molding process, you may have problems, such as parts deformation, structural weakness, surface blemishes, warpage, shrinkage, parting lines, voids, and air traps, to name a few.

All these problems may add to the cost of manufacturing. For streamlining the process, you have to use the trial-and-error prototyping process in a virtual environment.

Making tools that can help make high-quality injection-molded parts requires you to consider a lot of variables. For instance, it includes the optimal temperatures of the plastic, cooling channels, and the configuration of these systems, to name a few. Aside from this, you also need to consider pressure, flow rate, thermoplastic material type, solidification time, and so on.

If you have the required mold-filling simulation, you can easily balance the design against manufacturability. Moreover, mold makers can choose to optimize tools without the need for prototype molds. This way the manufacturers can also reduce run cycles, which results in better quality, reduced costs, and less time consumption.

Actually, the primary factor that you need to keep in mind in order to avoid the traditional problems associated with plastic injection molding is the accuracy of simulations.

Evaluating Manufacturability

With plastic injection molding simulation, designers can get answers to common questions related to part filling, air traps, voids, and gate locations, to name a few. With the help of these analyses, designers can perform the simulation of the mold-filling stage in order to understand whether it can speed up the tooling design and production process.

Optimization of the Mold Design

The primary goal of a Chinese mold maker is to develop injection molding tooling that can produce quality parts without costing a lot of money. Moreover, this simulation offers extra tools to optimize tooling designers of different complexity levels. And this helps mold makers simulate different phases like filling and packing.

Improving Cycle Times

It’s really important to reduce cycle times by ejecting quality parts in the shortest time span possible. If advanced capabilities are used, plastic injection molding can help specialists hit the best balance between quality production and short cycle times.

All of this helps the designing and simulating of the cooling line layouts, processing parameter optimization and the making of conformal cooling systems.

Improving Mold-Filling Simulations

Nowadays, manufacturers can enjoy a lot of benefits by molding plastic parts instead of using the traditionally machined parts. For instance, they can reduce costs, scrap, weight and increase the design flexibility via the production of design and shape geometries that are more complex.

However, they can only enjoy these benefits if they boost the design and the productivity of the tooling. Nowadays, manufacturers can improve the performance and efficiency of their operations if they choose to replace or improve the conventional mold using the mold-filling simulations.

So, this was a description of some of the difficulties that manufacturers face during the plastic injection molding process and how these problems can be fixed.

Resource box: This article is originally posted in https://www.injectionmouldchina.com.

What are injection mold cooling systems?

02/26/2019Klarm Mould

As far as the plastic molding process is concerned, the injection mold cooling system plays a great role. Actually, this system directly affects the production efficiency, machine speed and the quality of end product. In the case of semi-crystalline polymers and amorphous, the highest level of heat efficiency is required. Let’s know more about this system.

The Design of Injection Mold Cooling Systems

First off, it’s important to keep in mind that the design of this system is of paramount importance. In fact, the cooling time accounts for up to 80% of the cycle. If the cooling system is properly designed, it can reduce the molding time for better efficiency. On the other hand, if this system is poorly designed, the reverse may happen.

So, the question is, what factors should be kept in mind for effective cooling? Given below are some of the major factors.

Plastic wall-thickness

If the plastic thickness is higher, it will take much longer to cool down. As a general rule, the cooling time depends upon the thickness of the parts of plastic. Ideally, it’s better to keep the thickness as low as possible.

It’s possible to choose low thickness, but it may not be possible for all types of projects. So, if the project allows some flexibility, the designers should not go for a higher wall-thickness. This is the number factor on the list.

Mold steel

If the steel has a higher thermal conductivity, more heat can be transferred. As a result, the cooling time will shrink. Typically, China injection mold maker uses copper in place of steel in order to get better results.

The layout of the Cooling line

It’s better to keep the mold cavity near the cooling pipes. Also, it’s better to have cooling pipes with higher diameters for better cooling. Therefore, the designer should consider these parameters in order to enjoy the best cooling effect.

Coolant

As the name suggests, coolants are the things used to cool down the plastic parts. Designers use different types of coolants. The two most common ones are oil and water. In addition, the thermal conductivity and viscosity of the coolant may also have an impact on the heat conduction. If the fluid viscosity is low, the thermal conductivity will be high.

The rules of designing a Cooling system

Ensuring highest cooling efficiency
Ensuring consistent cooling in order to avoid deformation of the objects
Facilitating the process of manufacturing

The goal of the cooling system is to ensure faster dissipation of heat from the objects. This ensures the best physical and dimensional properties. This requires a solid engineering approach in order to measure the injection mold performance with the help of water circuits.

Long story short, this is not a thorough list of factors that should be kept in mind when designing the perfect cooling system for injection molding company in China. However, with the help of this approach and good engineering knowledge, designers can get the best results. This will help them employ the right engineering practices and tools.

Resource box: This article is originally posted in https://www.injectionmouldchina.com.

How to design injection mold gate?

01/17/2019Klarm Mould

An injection mold gate is a small hole that allows the molted stuff into another mold chamber. For a successful design, designers have to consider a lot of factors, such as mold pate types, materials, location, dimensions, gate type, and many economic factors, just to name a few. Let’s find out how an injection mold gate is designed by a Chinese injection mold making factory.

Gate design carries a lot of importance if you want to get high-quality mold parts. Given below are a few factors that should be considered when designing the injection mold gate with injection mold design services in China. Read on.

Material

First off, choosing the right material is really important for the design process. Use the wrong material and be ready to suffer a loss. Based on the type of machine, the right material should be used.

Keep in mind that castings are strong enough to withstand the stress. For stronger parts, the cast material should be machined first. If you need to work on sharp corners, know that it can create difficulties during the molding process.

Size

The size of the gate also depends upon the resin and the part that you are going to mold. It’s important to note that small gates offer a better look but they take higher pressure or longer mold time for proper fill.

Also, high pressures in the cavity cause more stress, which can result in a structural failure.

On the other hand, bigger gates allow smoother resin flow and reduced mold time. Now, if the size of the gate is not right, it may restrict the molten resin. As a result, the material won’t be able to reach the next cavity. In another scenario, this restriction may slow down the filling rate, which may reduce the process efficiency significantly.

In the worst case scenario, if the size is not right, you may end up with gate defects, such as black streaks and mold warpage, just to name a few. So, the size of the gate is of great importance.

Location

Just like size, the location of the gate can have an impact on different factors. And these factors are extremely important for the whole process. Given below are some of those factors.

Aesthetics (flow lines, voids, sink marks, gate marks)
Operational considerations
Wrong flatness or roundness
Mold warpage
Part shrinkage
Wrong structure or strength of the part
Molecule orientation

At times, multiple gates are required in order to enjoy the best results. However, for using multiple gates, designers may want to take into account the meeting area of the flows, as this can cause many issues related to aesthetic and component weakness.

Defects

Now, let’s talk about the defects. Know that whether it’s the wrong position or size, any defect may cost a great deal of time and money. To correct the issues, the location of the gate may need to be changed. In some cases, the entire mold has to be re-configured.

So, these are a few things that can help you find out how you can design an injection mold gate by an injection mold maker in China.

Resource box: This article is originally posted in https://www.injectionmouldchina.com.

What Are The Purposes Of Hot Runner In Making Plastic Injection Molds?

12/14/201812/14/2018Klarm Mould

Basically, the injection molding process has been used the traditional way, which is known as the cold runner system. Nowadays, another method is getting popular. It’s known as the hot runner system. In this process, liquid substrate is put into the mold via a nozzle. So, the runner is kind of a passage through which the material travels. During the process, the substrate doesn’t cool down or get hard. Let’s find out why most people go for the hot runner for their plastic injection molds.

During a hot runner process, the mold is heated up and then cooled down once all of the cavity is full. Remember: the hot runner process may use many ways to heat up the injection mold, such as hot oil, hot water, induction/steam heating for quick heating. Unlike the cold runner system, this system cause fewer issues.

Now, let’s discuss why people go for the hot runner system in the injection molding process.

Less waste: This is an important point. In the hot runner system, the substance that passes through the chambers remains hot even when it reaches the last stage. In the cold molding, on the other hand, the runner is either discarded (waste) or recycled/reground. This is a disadvantage.

Quick cycle: As said earlier, the runner process requires time and may cause a loss of resource if enough time is not given. By fixing these problems, the hot runner system can boost the cycle times.

Keep in mind that the cooling and heating mold takes more time. Often, the time is offset through the savings from the elimination of the runner. However, it’s better to discuss the topic with your service provider.

Quality output: the removal of runners from the cold molded components requires a mechanical process. The product may get rejected if it is not up to the mark. In other words, the look and function of the product should be acceptable.

On the other hand, the hot molding can help resolve many issues, such as surface irregularities and burn marks, just to name a few.

Lower costs: cost is an importance consideration when opting for a cold or hot molding for a long-term. The initial cost of cold molding is less but the hot the hot runner system is a cost effective option as far as the long-term use is concerned.

Range of material: Actually, the inherent chemical composition of most of injection molding substance makes them a bit too “allergic” to temperature changes. The impact is stronger in extreme temperatures. So, for lower temperatures, the hot runner system is the way to go.

Colorant options: The hot runner system allows you to benefit from colorant mixtures in the process. So, this is another reason people opt for the hot runner process.

Long story short, these are the reasons the hot runner is an ideal choice for the majority of plastic injection mold projects. If you are looking to increase production in an efficient manner, we suggest that you give a go to this process. Hope this helps.

When it comes to hot runner injection mold, china plastic injection molding is the best choice.

Resource box: This article is originally posted in https://www.injectionmouldchina.com.

How to calculate production costs of making an injection mold

10/10/2018Klarm Mould

With the coming of the modern age, there have been a lot of new techniques that have been developed, but one can safely say that not all of them have been adopted by the industry. There are many reasons for it like they are not eco-friendly, or they can’t be easily automated, but the major reason that leads the way is they are not economically viable. There is no point in appointing a technique to produce something which is not worth the cost that one spent on creating it.

Injection molding is one such technique that has gained the attention of various industries and everyone is talking about it, but the same question still worries everyone, that what is the cost associated with it. In this article, we will try to describe how one can get a rough estimate of how much cost it will be on them once they start implementing the method.

Production rate: – One must have an idea about the product that they are going to make and how many cavities will be in there as it plays an important role in deciding the amount of material required which directly controls the total cost. Another thing that they need to aim for is the number of parts that will be produced in each cycle and the number of cycles in an hour. The larger the number of products produced in each cycle and the number of cycles in an hour, lower the cost of production.
The injection molding material used in each cycle: – It is not a good idea to simply measure the weight of the end product and then decide on how much material do you want. A substantial quantity of material is also scraped and wasted here and there and must be considered as well while calculating the material cost. An idea about the number of cavities that you will be having will also help with this
Other costs: – Other costs include the number of workers that you will be needing to carry out the different manual or automated operations. Workers doing manual work have low wages, but they will be needed in a large number while the workers working on the automated machine are skilled and will have a higher wage as compared to the workers doing manual work. Factors like the idle time of the different machines, post-processing time and the cost associated with giving final touches to the product must also be taken into consideration.

These are just some of the factors that go on deciding what the total cost will look like as they cover the core operations associated. Even the smallest of changes can go on to affect the total amount by a good amount and that’s why one should always aim to find the optimum method so as to balance all the cost involved resulting in the maximum profit that is the main goal.

Since China is the best place for any company to set up their factory, it is important to know about the China injection mold cost and on what factors does this amount depend on.

Resource box: This article is originally posted from https://www.injectionmouldchina.com.