The energy saving is the state-of-the-art of our time

Molding factories also need to be environmentally friendly

In recent years, we often hear terms such as SDGs and carbon neutrality. As a government policy, sustainable development and a decarbonized society are being promoted. Along with this trend, companies are also required to act responsibly.

The SDGs (Sustainable Development Goals) are sustainable development goals, i.e., they aim to establish economic development while taking the environment into consideration. Especially attracting attention is ESG investing.

ESG refers to investment that considers Environment, Social, and Governance factors, and is already becoming an investment trend. In other words, consideration for the environment and society is directly linked to corporate evaluation and corporate value.

These themes are no exception in the plastics industry. In recent years, the plastics industry has faced many environmental load problems. For example, discarded plastic waste flowing into the ocean can cause landscape destruction, environmental pollution, and adverse effects on marine ecosystems. In addition, there are concerns that eating such seafood containing microplastics of 5 mm or less may affect the health of the human body. Given this situation, environmental measures such as CO2 reduction will become essential in molding factory as well.

Therefore, this time, the theme is "environmental measures of plastic molding factory", and the energy conservation activities that molding factory can work on are divided into two parts: The first part and The latter part. In this article, we will focus on CO2 reduction.

Turn “waste” into “value”

It may be difficult to know exactly what to do when it comes to "consideration for the environment and society," but how about starting by eliminating the "waste" energy in front of you? Uka Energy saving means not only reducing our own electricity costs, but also reducing CO2 emissions in the process of generating electricity.

So, what kind of solutions are there to convert the energy wasted in the molding factory into "value"?

What consumes the most electricity in molding factories?

Is it wrong to say that molding machines consume most electricity?

Have you ever thought like this? It is difficult to save energy, because a molding factory is a large factory with a large number of molding machines. Because molding factories use a lot of electricity for the molding machines, and if we shut them down, our work will not get done."

In fact, the perception that "molding machines consume the most electricity" may be out of date.

It is true that conventional hydraulic molding machines consume a lot of electricity. Hydraulic molding factory have a simple structure, are hard to break, and have power. However, it seems that more and more factory are adopting electric molding machines for small items and precision molded products.

Compared to hydraulic molding machines, electric molding machines consume significantly less power, about 40 to 50%, and Power is overwhelmingly lower than before.

The key point under these circumstances is the auxiliary equipment.

Percentage of energy consumption

Molding machines are not the only equipment that consumes electricity in a molding factory. A large number of peripheral devices that require large amounts of power are used, such as dryers, Temperature controllers, Conveyors, and air conditioners.

Now let's look at the percentage of energy used in the molding factory.

This graph shows the ratio of actual molding using a 100 ton electric molding machine and measuring the Power consumption of each Equipment. As the graph shows, it was actually the dryer, not the molding machine, that had the highest percentage of Power consumption.

Waste leads to more wastes

What is wasted energy in the context of diverse power consumption?

For example, even when the molding machine is not running, peripheral devices such as Mold Temperature Controller and dryers are in operation and continue to dissipate heat. On the other hand, don't you always run the air conditioner so that the site doesn't get too hot?

Using electricity to generate heat and electricity to cool it down. In a sense, this is a situation where waste is leading to more waste.

To reduce such wasted energy, it is necessary to take measures for each equipment.

In this column, we introduce three of them: dryers, chillers, and  molding machines.

How to improve energy efficiency

Dryers

In the previous section, as a result of actual measurement in the test environment, we showed the data that it was the dryer that used the most energy in molding. In other words, the most effective way to save energy is to reduce the Power consumption of the dryer.

iplas dehumidifying dryer

Dehumidifying dryer equipped with a self-control function monitors the drying condition of the resin and controls Drying air flow rate and regenerated Air flow rate to maintain the optimal drying condition. Furthermore, the "Dehumidifying dryer MJ6-i" achieves significant energy savings by operating with the minimum necessary energy according to the amount of resin and the operating status of the molding machine.

There are also options that can be installed in existing equipment.

Valve-type drying optimization system

By adding a valve-type drying optimization system to the existing Dehumidifying Dryer (MJ3), the sensor monitors the temperature of the drying hopper and controls the Air flow rate, minimizing the power used by the heater. can be suppressed.

Exhaust heat recovery unit

By attaching the waste heat recovery unit to the existing hot air dryer (HD2) and reusing the waste heat, the electricity consumption of the Main body can be saved by up to 33%. As a result, it leads to reduction of waste heat to the work environment.

These solutions have the advantage of being relatively low cost and easy to realize the energy saving effect.

Hopper insulation cover

Wrapping the hopper with a heat insulating cover prevents heat dissipation and reduces the temperature around the hopper by 10 degrees or more. This stabilizes temperatures, saves energy and improves worker safety.

All of the energy-saving solutions related to dryers up to this point not only save energy in the equipment, but also reduce heat radiation to the work environment, which reduces the air conditioning load and makes it possible to use it with an air conditioner. It also reduces the amount of electricity consumed, which leads to improvement of the situation where "waste" produces "waste".

Chillers

Free-cooling system

Free-cooling system is a solution that saves energy by using the outside air temperature. The chiller is stopped when the outside temperature is low, such as in winter, and the water from the cooling tower is used directly as cooling water. It can save up to 54% of power compared to a normal continuous chiller.

Water cooling chiller

Our chillers equipped with self-control function enable significant energy savings by using an inverter to control operation according to the heat load situation.

Click here for details ⇒ Water-Water cooling Chiller inverter control MCC5-i

Molding machines

The main body of molding machine is difficult to reduce energy consumption by modifying the moving parts. However, it is possible to suppress the energy required for temperature rise by suppressing heat dissipation and heat transfer generated from the heating cylinder and mold during molding.

Cylinder heat insulation cover

By wrapping a heat insulating cover around the heating cylinder (cylinder), heat dissipation is suppressed and the heating efficiency of the heater is increased, which simultaneously realizes energy saving and reduction of the load on the work environment, and also helps prevent burns to workers. Wiring is required, but the ease with which it can be installed simply by winding it is also fascinating.

Mold insulation plate

The temperature of the mold is controlled by Temperature controllers, but if left as it is, the heat will escape from the mounting part between the same metals. By inserting a heat insulating plate between the mold and the mounting plate (platen), unnecessary heat transfer is suppressed, which reduces the temperature control load and saves energy. In addition, since the temperature distribution in the mold is constant, stable molding can be achieved, leading to improvements in the dimensional accuracy and appearance quality of molded products.

In addition to the solutions introduced above, we offer a wide variety of methods and items. We will work with you to realize an energy-efficient and comfortable molding factory that meets your factory facilities, budget, and initiatives.

Summary

When we talk about CO2 reduction and sustainability, we tend to see it as a topic in the distant world, but if we start by reducing wasted energy in our factories, the topic becomes more familiar.

Saving energy in a factory can start with simple things such as keeping things tidy and turning off equipment that is not in use. Then, new solutions can be introduced to achieve higher effects. This is a good time to invest in this area, as the cost of power is skyrocketing.

Savings on power costs will directly reduce CO2 emissions, which increases the value of your company. We, Matsui, offer solutions to reduce resource consumption and increase corporate value. Please feel free to contact us if you have any questions about environmental measures or energy saving in plastic molding.

CX Design Department Yasuhiko Iijima