Tag: <span>cooling process</span>

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Thermoforming is the process of heating huge plastic sheets into a very high temperature and cooling them in the required format. Vacuum forming is a sub process or a type of thermoforming where vacuum is applied in between the molds and the plastic to create various shapes. Thermoforming has several advantages and disadvantages compared to the other plastic molding methods like injection molding. In addition to vacuum forming, several other methods like drape forming, twin sheet forming and pressure forming can be incorporated along with thermoforming to produce different kind of products. Several types of plastic can be molded in the method.

Disadvantages of thermoforming

1. Thermoforming is quite costly. Compared to other methods like injection molding, this method can cost up to 50% more.

2. Large plastic sheets are used in the method. They have to be fed into the rollers again and again. This leads to lots of extrusion.

3. The plastic street is stretched in the under pressure in this method. Hence the products formed using thermoforming break at a certain temperature.

4. Thermoforming uses more plastic than other methods. Nearly 10 to 20% more plastic is used to make any product in this method. This adds to cost and creates extensive wastage too.

5. Vacuum forming process done along with thermoforming does not give the required shapes sometimes. The whole process has to be repeated which is expensive as well as time-consuming.

Advantages of thermoforming

There are several advantages in using this method in spite of all these disadvantages.

1. Thermoforming is the only method in which huge plastic sheets can be molded into huge objects. All other methods are used for making small objects only.

2. Though the process is costly, the tools required for the trade or quite cheap. Injection molding machinery is nearly 33% costlier than the Thermoforming machinery tools.

3. Several different products can be prepared in the thermoforming machines. Only certain products can be prepared in other machines. Nearly all types of plastic can be used for the plastic. Other methods use only specific plastic for production.

4. Skilled labor to operate the thermoforming machineries are available in abundant. But, laborers capable of operating machineries of injection molding or vacuum forming are quite less.

5. Superior quality products using more plastic are formed in the method. Hence, they are more durable than the objects created through other local methods.

There are many more advantages in the method. Though costly and a bit time-consuming thermoformed products are preferred by most of the packaging industries due to their high quality.

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Source by Lavanya Senthil

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Plastic injection molding is a popular section of the plastic industry. This process is used for producing plastic components. Typically, this process is fast and produces a lot of components in a short period of time. Common materials used for the production include metals, elastomer, thermoset, and thermoplastic just to name a few. Let’s find out more.

Plastic Injection Molding Industry

Plastic injection molding is used all over the world for making plastic components of toys and medical equipment. In the automobile and aerospace industry, millions of components are made using the same process. If you look around, you will find hundreds of things made with plastic molding.

Recently, this industry has gone through a lot of changes. Nowadays, manufacturers work with different tooling partners in order to reduce the lead time.

How does the Process Work?

Basically, the injection molding process involves melting plastic in the machine. Afterwards, the melted plastic is put into a mould with high pressure. In the mould, plastic is solidified and released through the opening. This technique helps produce different objects.

Before the production begins, the components are carefully designed by an experienced designer or engineer. In the next phase, an experience professional prepares the mould. Typically, aluminum and steel is used for making the mould.

The plastic is put into the molding machine. The machine stays closed throughout the injection molding process.

Typically, the plastic is injected into the mould in the form of pellets or granules. The machine keeps on heating the plastic in order to liquefy it. At the end of the process, ejectors push the component out of the mould in the form of a finished product. This is how the whole process works.

How to Speed up the Process

The injection molding process can be boosted by reducing the injection time, resetting time or cooling time.

How to Reduce the Costs of Injection Molding

For best results, you need to you choose an automated mode change. This will reduce the changeover time and make the manufacturer more flexible as far as the production quantity goes.

Magnetic Clamping Systems

With the help of magnetic clamping systems, it is possible to speed up the process of injection molding. This system is engineered to be used in molding machines with mold.

Given below or three things that are taken into account for innovative design:

• Temperature Range
• Opening and Holding Force
• Daylight Opening

Nowadays, you can choose from a variety of magnetic clamping solutions. There is a lot of variety because one machine cannot meet the needs of all manufacturers

Based on your needs, you can choose a small or large molding machine. For example, if you have a large unit, you can choose a machine that weighs more than 400 tons. Most of these machines feature touch screen controls so you can operate the machine accurately. This way the machine can work better and you can rely on it to meet your needs.

So, this is a brief introduction to the molding and the process it follows.

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Source by Dong Wong

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Goji berries can be used in any form – some people love to buy dried goji berries while others love to have these berries in its fresh form. If you are a lover of goji berries, you can also dry these goji berries all by yourself and enjoy the benefits of this wonder fruit. Goji berries are said to be one of the newest forms of super fruits that are available. These tiny berries are richly sourced in antioxidants which make them highly beneficial. If you dry them, it means you are in a way concentrating their potency factors. If you are growing these goji berries at home and would love to dry them, you can carry out some of the following steps.

Goji berries is an easy task, you just need to know about the right way to do it. In order to dry these berries, you will need a baking sheet which has half inch high edge all around it. You will also need a cooling rack that is used by bakers so that it fits on the baking sheet. You will also need a cheese cloth so that you are able to cover the cooling rack properly. Besides this, you will also need an oven and zip top storage bags for the drying of these berries.

The process of drying goji berries starts with rinsing and drying of these berries. You have to discard all those berries which are not fully ripe and also those that have become quite moldy. This means that these berries are not fit for the process of drying. Once all these berries have been cleaned properly, these need to be placed in the cooling rack just on top of the baking pan. This initiates the drying process of these berries. Once you have placed them on the baking pan, you can now cover the rack with the berries on it with the help of a cheese cloth.

When you are using the cheese cloth, you have to make sure that you are spreading all the berries which you wish to dry evenly on the cheese cloth. There should be good space between each berries so that the berries do not touch each other or even stick to another. This is basically to ensure that the berries get dried well and through out are dried very well. It is now required to place this baking rack along with berries just inside the oven. You have to keep the door of the oven open and turn it to a low setting. No matter what type of low settings you have, you have to ensure that you are setting your oven at its lowest level.

Goji berries might take a lot of time in drying. They might take twelve hours to become leathery and pliable. The time which is taken for getting these berries dried, is usually dependent on the temperature they are kept in and the number of berries which are being dried. If there are many berries, it will surely take a lot more time.

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Source by Tim O’Shea

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Welding: An Introduction

Welding is commonly done to join two materials, usually metals. However, these days, the process of welding is used for joining plastic and glass items too. Metal welding process is fundamentally different from plastic welding or glass welding. Read on for more.

Difference in the Vibrations

In case of plastic welding, longitudinal vibrations are sent to the weld surfaces whereas parallel vibrations are responsible for successful metal welding. Also, in case of metal, friction does not lead to easy melting of the surface. In plastic welding, the material melts due to frictional action, and that too at a much lower temperature compared to that put in use during the metal joining process.

Welding Tools

Since the metal welding industry requires fusing of thicker materials, the apparatus used for the purpose are different than those in use for glass or plastic. Although both types of welding tools are manufactured on the basis of the common principle of acoustics, there are some differences in their shapes; which in turn sends out different kinds of vibrations to the weld surfaces.

Main Stages of Plastic Welding:

Plastic welding is primarily done to create a stronger molecular bond between two thermoplastics. The process consists of three main steps:

Pressure: Pressure helps in flattening the surfaces of the objects to be welded and has to be applied for keeping their different parts in proper orientation.

Heating: Intermolecular diffusion is allowed in the heating stage for better fusion.

Cooling: This stage is important for solidifying the newly created molecular bond and leads to proper weld strength.

Plastic soldering makes use of different types of processes such as spin, vibration, laser, ultrasonic, etc and each of these processes differ from each other in their individual methods.

Glass Welding Process

Glass welding is usually done at the time of manufacturing glassware, constructing neon signs, flash tube and scientific apparatus. Also, bottles and jars require glass welding to join the different glass molds. In glass welding, the glass is melted into a thick liquid mass, which in turn is heated under very high temperature. However, the temperature required in glass welding depends on the types of glass involved in the process. The melted glass is heated using a particular type of gas torch.

Conclusion:

Whether it is about welding metals or glass, the overall process is as simple as heating and joining with the use of technology. However, there exist certain differences, which need to be mastered for best results.

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Source by Nagender Singh Jatav

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A combination of steel with different elements in various proportions is called as Alloy Steel. The low alloy steels are generally referred as alloy steels, ranging between 1% and 7%. They are Chromium, Nickel, Molybdenum and Vanadium.

Properties of alloy steels:

It contains about 1% to 5% of steel that is combined with other elements. Different alloy elements have unique properties and adding these elements improve various qualities. Adding Chromium improves the temperature strength to heat treatment. Nickel is added to improve toughness. Molybdenum increases the strength of the material and vanadium increases the deoxidizing capabilities and offers corrosion resistance. All low alloy steels provide good toughness, torsional and fatigue strength. They also have photo active and semiconducting properties that make them fit for electronics applications. They are used as good catalysts for various industrial applications. With a range of properties they remain as the cost-effective additives that are combined with steel alloys.

The common properties of alloy steel are Corrosion Resistance, Machinability, Hardenability and Weldability.

Corrosion Resistance:

Corrosion is a phenomenon in which the metal is corroded or destroyed due to oxidation. This causes rusting of the metal surface. It has corrosion resistance properties to stop the rusting of the metal surface. Chromium, Nickel, Molybdenum and Vanadium alloys show high resistance to corrosion.

Machinability:

It is the capacity of the metal to undergo changes easily when subjected to various mechanical processes to get the desired result. Chromium, Molybdenum and Nickel show very good Machinability. In some cases it should be annealed.

Hardenability:

It is the property of the steel alloy to be hardened after heat treatment and cooling. In this process the metal transforms from an austenite to a martensite at a particular temperature condition. All the low steel alloys show good hardenability.

Weldability:

It is the ability of the metal to undergo the process of welding to be welded or joined to other surfaces. All alloy steels have good weldability. With the combination of Molybdenum, Chromium and Nickel, pre heating and post heating must be done while welding is carried out on large sections.

Uses of Alloy Steel:

They are used in various applications such as pipelines, auto components manufacturing, electric motors, axles and shafts of power transformers, generators, aircraft engines mounts, landing gears, wear resistant coatings, manufacturing power electronics components, hot zones of furnaces, electrodes manufacturing, solar cell coatings, magnets, radiation shields, forging dies, oil and petrochemical industries, production of lubricants and smoke suppressants.

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Source by Amy Anderson Lee

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We live in a world surrounded by electrical appliances. To beat the heat or to get a warm zones in our homes, appliances have made all this possible. All this happens because of the human brain and the technology. Where else to give the credit for it? We live in a life surrounded by technological developments. Especially the development made in the domestic electrical appliances market. So let’s have a look at the same, because it’s been long that we appreciated this boon.

So what all can be included in the domestic market? A lot of things, the whole house and the kitchen specifically, there are appliances. The best has been done in connection with room cooling and also heating. We need to see the same!

Room coolers: Air coolers have been on the upfront of technological developments. Also, it has been the oldest form of cooling in our homes. The simple motor uses water and sprinkles cool water over us. Delightful as it sounds, when you sit in front of it, you forget that its summer. Further, it has also evolved, from iron boxes to plastic and automated functioning there has been a lot of change.

Air Conditioners: A better and larger version of the technological developments is the air conditioners. Though they give a lot of cooling and also monitor the room temperature but at the same time, and on to pollution because of chlorofluorocarbons. Hence, to stay closer to natural air, better to opt for the other two options above.

Exhaust Fan: Well, small areas and too much cooking, disturbs are breath. So exhaust fans came in as savior to provide clean air. Exhaust fans help keep ventilation in process and also, in places which are compact or filled with lot of people, ensure that there is proper air.

Ceiling Fans: A more modern form of cooling, but have been around for quite some time. The looks for sure have changed. There has been modification in terms of the type of blades, designing and also the feature of having light installed on to it. Ceiling fan manufacturers have been working hard on this product and hence keeps working to enhance the motor to ensure better quality and also to have an edge over the competitors.

Room heaters: In winters, this comes handy to control room temperatures and provides an escape from all the winter chills and the freezing we feel. It is an upgradation of the fire places, because we can’t install it in all the homes as of now. The modern day electrical appliances still can’t beat this product. So, to improve the heating and because central air conditioning too expensive, we have heaters!

All these developments, help us have a better living. The end target is to enjoy life and have the state of the art products, to beat the climatic changes, but still caring about the nature at the same time. Let there be benefit of both and not just the humans. For, the love of human ease and environment peace, stick to those appliances which don’t harm others!

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Source by Karann S Singh

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The vacuum coffee maker has been around for over two hundred years when it was invented by the German company Loeff. They are very popular in Europe and Japan, but lost popularity in North America with the invention of the electric and drip makers. However, many aficionados recognize they make a delicious cup of coffee and these machines are making a comeback in the U.S. and Canada.

The reason why these machines make such delicious coffee is due to the fact that the vacuum created during the process of heating and then cooling down the water results in the coffee being brewed at an optimal temperature.

A vacuum coffee maker has two pots, sitting one on top of the other. The two pots are sealed together with a rubber gasket or some other type of seal and there is a siphon tube running between the two. When the water heats up in the sealed bottom pot, water vapor is created due to the vacuum or pressure that is created. The water is forced up the siphon tube by the water vapor and is combined there with the coffee grounds. This vacuum process creates an ideal temperature for brewing coffee.

Once the maker is removed from the stove or other heating source, the vacuum or pressure is released and the coffee runs back down the siphon into the lower pot. The coffee brewing process is now complete.

The coffee produced by a vacuum coffee maker is rich and smooth. No wonder these makers are making a comeback in North America!

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Source by Jules Wright

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Split air conditioners are an ideal choice for most consumers as far as purchasing air-conditioners are concerned. The word “split” is used because half of the system is installed inside a building and the other half is installed outside. In other words, the compressor is installed outside while the duct system is installed inside. This is the reason the installation and setup of this system take a bit more effort. In this article, we are going to share with you are few tips for AC installation. Read on to find out more.

The internal and the external part

The beauty of a split AC is that it requires no expensive duct system, which is why this system is an ideal choice for garages and other areas of your office or home.

First of all, there must be a hole to connect the inside unit to the outside one. For this purpose, you need to run the refrigeration lines to the ventilation system sitting outside.

So, your first move is to decide on a location where you want to mount the air conditioner inside your room. Apart from this, you need to cut a hole for these lines.

3 Sections of a Split AC

There is no need to mention that you need to follow a couple of important steps if you want to install a split air conditioner. The three primary parts of the AC are the connectors, the inside vent, and the outside condenser. Let’s find out more.

Outside condenser: This is the large part of the AC, which looks quite similar to the central air conditioning unit. Since a consumer air conditioner does not have a lot of cooling capacity, these condensers are smaller in size.

This unit is placed outside in order to prevent noise so that the residents don’t get disturbed. Apart from this, this component contains the ventilation system for the internal unit.

Inside vent: It refers to the brain of the AC. This section controls the temperature and delivers cool air. As a matter of fact, the condenser does the hard work and brings the cool air inside.

The connectors: This component is used to make a connection between the two parts of the air conditioner. The wise transfer electricity and the tubes dispense the water formed during the cooling process.

The entire setup is simple but requires some effort and time. So, if you follow the description given in this article, you will be able to install your split AC much more easily.

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Source by Abdul Waheed Zafar

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A good running vehicle is what most car owners would like to have especially if it is needed for their job. Police cars are examples of vehicles that need to be fast and always in great condition so they can catch criminals and respond to calls the fastest possible time. Now, for this reason, there are many vehicle accessories that can help speed up your unit, add more power and make it run more smoothly. A turbocharger is one of the most important accessories for your vehicle. Turbochargers can increase your engine power as much as 35% compared to having no turbocharger.

All vehicles whether it is run by diesel or gasoline must have a turbocharger in their engine. The turbocharger helps increase engine horsepower. Usually, a single turbocharger is used for diesel engine while two turbochargers are used for gasoline engine and it commonly referred to as twin turbo.

The main function of turbocharger is to increase the amount of air intake needed by the engine for better fuel combustion. It is actually connected on the exhaust manifold of the unit which is made of two kinds of impeller separated by a chamber. As the exhaust manifold releases air, it actually rotates the impeller of the turbo charger in the exhaust manifold side and since the two impeller of the turbo is directly coupled together, the impeller on the other end which is directly connected to the intake manifold would eventually turn itself adding air in the combustion process.

Turbocharger impellers rotate almost 3000 rpm and because of this it is prone to overheat just like the engine itself. There are two cooling processes done for turbo chargers to prevent overheat, the first is by using oil lubricants and the second one is through combination of water and oil lubricants. In oil lubricants, the turbo charger is regularly fed by engine oil through a steel pipe directly connected to the main engine. It cools down the turbo charger by lubricating its rotating parts which is the impellers and because of this it easily cools down itself. The combination of water and oil, it is usually used on large turbo charger, because engine oil is sometime not enough to cool down the turbo. A connection directly connected to the water passage way of the engine is connected and passes through the turbo to cool it.

One way of maintaining the good condition of your turbo charger is by ensuring that there clean engine oil is always present. You should also regularly check for any leak or damage in its connection. Avoid engine revolution especially when you have just started your engine. Owners have experienced turbo charger problem when they turn on their engine and run their car without allowing it to heat up especially on a cold weather. The usual turbo damage is mostly in the impeller itself because it is usually broke down into pieces when damaged. Now the most important thing to maintain the turbo in good condition besides checking its cooling system is by avoiding early engine revolution. It is also best to start the engine and wait until it reaches a designated temperature before running your vehicle.

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Source by Thomas Glickman

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Ice Thermal Energy Storage (TES) has the advantage of universal availability, low cost and transport ability through other system components. However, a conventional ice TES system for air conditioning application requires low temperature chillers and therefore standard water chillers must be replaced with low temperature glycol chillers which operate with a lower evaporation temperature and consume more power.

If we can offer designers an ice which freezes and melts above or below 0°C (32 °F) these new products will open new horizons for environmentally friendly and economical systems for both New and Retrofit type process cooling / heating load shifting applications.

Phase Change Material (PCM) Eutectic solutions are  mixtures of two or more chemicals which, when mixed in a particular ratio, have a freezing / melting point below or above water freezing temperature of 0 °C (32 °F) and they offer a thermal energy storage facility between -114 °C (-173 °F) and +164 °C (327 °F).

Eutectics are well-known and in fact early applications date back to the late 18th century however the separation and the life expectancy of these mixtures were unpredictable and therefore their wide spread usage was limited.

The disadvantages of a conventional HVAC chiller and ice (water ice) storage system can be overcome by utilising the latent heat capacity of various “Eutectic” mixtures without the need for minus circulation temperatures. 

Phase Change Material (PCM) thermal energy storage not only enables the designer to utilise existing chiller technology but also enables charging by means of free cooling, i.e. without running the chillers

Although the term “Eutectic” is widely used to describe the materials we are interested in, a better description would be “Phase Change Materials” (“PCMs”). Unfortunately, very few of the documented PCM solutions are true Eutectics and so many have to be modified to obtain a material suitable for long term use.

PCMs can be broadly grouped into two categories; “Organic Compounds” and “Salt-based Products”. The fundamental requirement for a modified Eutectic (PCM) Solution can be classified in three categories, namely stable solution (no separation or degrading), minimum supercooling / heating and finally close freezing and melting temperatures.

There are three fundamental additives commonly used to modify hydrated salt based Eutectic PCM solutions. These three components are firstly Nucleating Agent which encourages Crystal formation and therefore minimizes super cooling and the secondly additive is Freeze Depressant to achieve a lower phase change temperature and thirdly Gelling / Thickening Agent in order to overcome separation and degrading problems.

Once the above components have been carefully applied, a satisfactory Eutectic PCM Solution can be produced from the physical and thermodynamic point of views and commercially available solutions offer a range of  -114 °C (-173 °F) and +164 °C (327 °F).

However, majority of suitable PCM solutions for HVAC and refrigeration systems are corrosive to commonly used pipe and line components and therefore suitable encapsulation techniques must be applied to overcome this problem while providing the best thermal performance. Various encapsulation techniques such as tube, flat container or alternatively ball concepts have been developed whereby the PCM solutions are encapsulated in plastic and / or metal shell.

The heat transfer between the surrounding media, which flows around or inside the unit and the surrounding PCM solutions, takes place from the outer or inner or the combination of both surfaces of the encapsulated PCM unit. These techniques are generally eliminates the contamination risk and offers an efficient, cost effective, practical and flexible new type of TES designs.

Modern society’s reliance on refrigeration and air conditioning indicates that refrigeration and the associated environmental issues will be with us for a considerable time and therefore one has to utilize existing and available alternative technologies with minimum usage of energy.

A Positive Temperature Eutectic Phase Change Material (PCM) Thermal Energy Storage (TES) not only provides the end user with an Environmentally Friendly design but also the following additional benefits can be obtained:

o Reduced Equipment Size

o Capital Cost Saving

o Energy Cost Saving

o Environmentally Friendly Installation

o Improved System Operation

o Flexibility for the Future Capacities

The temperature ranges offered by the proposed PCM solutions utilize conventional chilled water temperature ranges for both the charging and discharging sides of the system. Hence, they can be applied to any new or retrofit application with minimal technical and economical impacts.

Furthermore, the possibility of Free Cooling Cycle, Absorption Chillers, Co-Generation, Solar, Hot Water and Heat Recovery TES system combinations offer new horizons for designers to control the energy balance to match the load and electricity demand / consumption of the system as a whole.

The task for designers is to explore all available technologies towards achieving improved efficiency regardless of which refrigerant is used, and apply where and when possible diversification technologies in order to minimize the overall CO2 emission related to energy usage. A carefully balanced Eutectic, Phase Change Material (PCM) Thermal Energy Storage (TES) may be the answer for some of the cooling applications for an Environmentally Friendly and Economical alternative.

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Source by Zafer Ure