Blown Film Extrusion Introduction

Blown Film Extrusion Introduction
Blown film extrusion is a technology that is the most common method to make plastic films, especially for the packaging industry. The process involves extruding a tube of molten polymer through a die and inflating to several times its initial diameter to form a thin film bubble. This bubble is then collapsed and used as a lay-flat film or can be made into bags. Usually polyethylene is used with this process, and other materials can be used as blends with these polymers. A diagram of a polyethylene chain is shown in Figure 1 to the right.
Background Theory on Polymers

In the cooling step of blown film extrusion, the amorphous, transparent melt crystallizes to form a translucent, hazy, or opaque film. The point where opacity begins in the bubble is known as the frost line. 
Fig 1: Model of polytheylene chain frompolyethylene Wikipedia article.The frost line height is controlled by several parameters: the air flow, film speed, and temperature difference between the film and the surroundings. Properties of the film, such as tensile strength, flexural strength, toughness, and optical properties, drastically change depending on the orientation of the molecules. As the transverse or hoop direction properties increase, the machine or longitudinal direction properties decrease. For instance, if all the molecules were aligned in the machine direction, it would be easy to tear the film in that direction, and very difficult in the transverse direction.

The Film Blowing machine Process

Fig 2: Schematic of set-up from User:J.Chiang.

Typically, blown film extrusion is carried out vertically upwards, however horizontal and downward extrusion processes are now becoming more common. Figure 2 shows a schematic of the set-up for blown film extrusion. This procedure consists of four main steps: The polymer material starts in a pellet form, which are successively compacted and melted to form a continuous, viscous liquid. This molten plastic is then forced, or extruded, through an annular die. Air is injected through a hole in the center of the die, and the pressure causes the extruded melt to expand into a bubble. The air entering the bubble replaces air leaving it, so that even and constant pressure is maintained to ensure uniform thickness of the film. The bubble is pulled continually upwards from the die and a cooling ring blows air onto the film. The film can also be cooled from the inside using internal bubble cooling. This reduces the temperature inside the bubble, while maintaining the bubble diameter. After solidification at the frost line, the film moves into a set of nip rollers which collapse the bubble and flatten it into two flat film layers. The puller rolls pull the film onto windup rollers. The film passes through idler rolls during this process to ensure that there is uniform tension in the film. Between the nip rollers and the windup rollers, the film may pass through a treatment centre, depending on the application. During this stage, the film may be slit to form one or two Read More..

Lessons Learned About Technology


The exclusive right to do something defines the term patent. It is also commonly known as copyright. These rights are provided for legally making them legally enforceable. Getting a patent is quite a tedious procedure. There are several considerations that one as to put in mind. The most important should be the cost of obtaining a patent. This is because there is a certain cost to be met to obtain a patent and this cost varies.

In order to obtain a patent for a certain product, its subject matter should meet the legal provisions regarding the same. It is beneficial to check if your product can be patented as per the legal provisions.This will save you the energy of going through with the process if your product does not qualify. Your new idea should have the chance to provide utility. This translates to the idea that the innovation should be usable in its field of use. This idea should not have been advanced before as it should be at its first instance making it new.
The innovation should be unique in that it should not be an obvious idea. Some energy should have been utilized in coming up with the idea. The information regarding the idea should be a secret and kept away from the public.

There are three general categories of patterns. These categories cover various items that can be patented. Utility patent is the first category. It is available for ideas that govern processes such as improvements to products already in existence. Design patents legally protect the matters concerning the appearance of the product. Newly invented products which did not exist prior to this event are patented under the category of plant patents.

It is burdening to obtain a patent as already stated. It is important to hire legal help to ease this process. The help needed throughout this process can be given by patent lawyers. Hiring the services of a patent attorney is therefore very useful. The attorney should be very conversant with all matters concerning patent laws. The time spent on searching for the patent attorney manually can be saved by carrying out a google search. It will avail you various options of patent attorneys from which you can choose from. Once you settle one, agree on a certain amount of fee and let them start their work. Obtaining a patent is a very smart business move. The idea of obtainig patents shoud be instilled in creatives and innovates and this service offered to them.… Read More..

Lessons Learned About Services

Guidelines for Picking the Right Masonry Services

The current days have seen an increased use of new building materials in the construction industry. This is on the grounds that people are trying to come up with sustainable building materials. You will get that building a house or any building for that nature as a lot of processes involved in it. You will need to first start with designing the building in question. A structural engineer will have to help you in designing the building. This mostly applies for skyscrapers. A structural engineer is not needed in the design of all the buildings. There are buildings where the masonry is the one that carries all the loads that are applied to the building. Masonry services are required in both the first and the second instant. There are a lot of challenges that may be involved when trying to come up with the right masonry contractor. This is due to the fact that the construction industry today as so many masonry contractors. Therefore, it will be a problem for you to select the right contractor. Nonetheless, you are in the right track in starting to conduct research about these masonry services. This article is meant to guide you on picking the right masonry contractor. Some of the tips that will help you in choosing the right masonry services are discussed beneath.

To start with, you will need to find masonry services that are within your budget. You should remember that for you to get quality services you will need to spend. Therefore, you will need to spend more money to get these quality services. For those that do not have the right amount of money to get quality services, you can begin saving. Those that choose cheap masonry services should know that in the end, they will pay for them. This is on the grounds that cheap products will ultimately make you spend more money.

Moreover, it is important to look at the experience of the masonry contractor in question. You should go for those masonry contractors that have been in the market for a long period. This is on the grounds that they are used to the industry and thus can tell any change that occurs. Thus, they can be able to handle any challenge that they may encounter. Likewise, a long period in the industry means that the public trusts them.

Lastly, you should ask for a recommendation from your relatives and colleagues. You might have close friends or member of the family that at one point may have used masonry services. This is the perfect place you should begin from. This is due to the fact that you will get masonry contractors that you will trust.

Smart Ideas: Services Revisited

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The Path To Finding Better

Information You Need to Have When Selecting an Insurance Company

Purchasing an insurance policy is very important and can be overwhelming when you are buying. There are many oakville insurance brokers and new people who are trying to sign up a contract, people may have a hard time trying to distinguish between the best one and those that are just online to end up scamming people. There is a need to have an insurance as an individual, you can imagine losing everything to fire starting from your home, cars and other assets, an insurance will help you get life on track once more. This blog will guide you on the important things that you need to consider when you are choosing the right Home and Car Insurance in Hamilton.

Ensure that you know a procedure that should be used to verify more and check the reputation of the error and omission insurance ontario that you are working with. There are a number of websites that you may know in your local area, ensure that you list them down. You will know how long the business has been able to exist. You would like a company that has a vision, mission that go hand in hand with what you want in life with your family. There are also clients who normally place reviews on the sites, be sure to check so that you get more details on the best one of them.

Once you have figured out who will be your referrals, you can prove that everything works best for you now the one thing you need to do is ask. Now that the job is going to be very easy, you do not have to go through all the hassles of the internet now that friends and relatives can lead you to the best referrals. Therefore, ask the friends you have had talking about how they deal and pay for their insurance. If the providers usually offer them with the right experience; then there is no need to keep searching because you now have the right company. All you need to do is to ensure that you will have the best experience when you choose Morison Insurance Hamilton.

Before you can sign that contract, it is essential that you ensure that you have chosen a company that will be existing for long. Some error and omission companies with a weak financial strength will not deliver its services to you for a long time. This is because it does not have the ability to support itself in the industry. If you choose a company whose strength of finance is very weak, you will be surprised because, at the end of the period, you will not get the kind of claim that you needed. It is essential to ensure that the Morison Insurance Brokers Inc. will be worthwhile for the charges you pay for.

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Case Study: My Experience With Patches

Custom Patches and Emblems

Emblems and patches are very popular in the modern day because we see them on a lot of items . Emblems and patches can either be embroidered or woven. Custom patches have some very unique shapes that make them unique. Patches are permanent when put on fabric. Unlike clothing labels patches are fixed on the outside and are not to be cut off. Patches can be made to look conspicuous and they come with logos, emblems and some written information written in them.

Woven patches have higher definition in terms of the lettering, edges and generally how they are put together if compared to embroidered patches. They are also surprising cheaper to manufacture with almost half the cost difference making them very ideal if you have a project at hand to consider. Laser cut and die cut are shapes of patch work that are not in square. Patches are a lot larger than the normal clothing labels and that allows them to contain logos, emblems and even writings. The unique thing about the embroidered patches is that they have a higher three dimensional lift to the fabric . Creating such a masterpiece however requires dense stitching and the use of thick embroidered threads. Embroidered stitching gives you a classy look but if you want to capture finer details of a loo or writing it does not work out that well. If you have a project that you want done with customized emblems and patches you need to think about the budget and graphic requirements first.

Manufacturers know a lot about patches and emblems, consider having sit down with them so you can brainstorm on your customized order, The ideas that the manufacturer has might impress you enough such that you want them on the product that you ordered. Consider the time gap that you want the product finished once you place an order with the manufacturer , custom pieces could have a lot of work involved and hence the need to ensure that everything falls within the time gap that is suitable for you. If the order that you placed is to grace an event consider placing it as early as you can so that you can beat the last minute rushes that come with placing an order late. You will have an easy time when you make an order during that time when the manufacturer does not have a lot of clients to serve than the peak season when everyone is rushing. Check to see of the manufacturer is using the quality of thread that you want.

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