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Have you been looking for a simple and easy way to package materials for transport or storage? If so, the stretch film could be the answer. This versatile product is inexpensive and provides effective protection against moisture and dirt. With our step-by-step guide, you’ll soon discover why the stretch film is one of the most popular ways to package items with advanced security! Here, you can find out how to use stretch film efficiently – from choosing the right type to achieving a secure seal – plus tips on calculating how much material your task requires. Whether you need it for shipment preparation or safeguarding stored goods in warehousing operations, this helpful guide has all the information needed to make sure you get professional-looking results every time.
Steps on making the stretch film:
Step 1. Extrusion
Step 2. Blown Film Extrusion
Step 3. Air Ring Cooling
Step 4. Winding
Stretch film is an important tool used to secure products and containers before shipping or storage. This flexible plastic wrap serves many purposes; it prevents unit loads from spilling or shifting during transit, protects products from dirt and dust while in storage, and can even help reduce warehouse costs by enhancing the visibility of inventory levels. It also provides an economical means of packaging as well as offers moisture protection for certain products.
The Step-By-Step Guide to Making Stretch Film is a comprehensive guide for anyone looking to understand the process of making and using stretch film. Whether you are a veteran in the industry or just starting, this guide will provide the expertise and knowledge needed to ensure you make a successful product. From selecting the right type of film for your needs to mastering application techniques, this resource has it all.
Definition of Stretch Film
Stretch film, also known as stretch wrap, is a highly elastic material made from thin plastic and is used to secure objects together. It is available in a variety of materials including polyethylene and PVC. Stretch film is applied by hand wrapping or with a machine wrapping, depending on the size and shape of the items being wrapped. Blown stretch film is created when heated air blows over molten resin which quickly cools it into thin sheets. This allows for faster production with lower thicknesses than can be achieved with regular stretch film
Stretch wrap film has many advantages compared to other packaging materials such as boxes or tape. It provides excellent protection against dust, moisture, abrasion, and shock while still allowing for quick and easy wrapping of products. Additionally, it uses less material than box packaging which saves costs without compromising product protection. Stretch wrap equipment includes stretch wrap machines that are designed to apply the film evenly over any size product at great speeds while using minimal amounts of film per application. Pre-stretch films are available where the length of the film has already been stretched out before application which reduces cost and wastage further while increasing the speed of application.
Stretch wrap is the perfect option for businesses wanting to bundle and protect their products during shipping and storage. It can be purchased in a variety of forms, such as a blown stretch wrap, pre-stretch film, and cast stretch film, that offer different levels of cover, cling, and strength depending on your packaging needs. Cast film offers great longevity and clarity for the user and is best for wrapping products that need to be on display. Businesses should consider using a stretch wrapping machine to quickly apply the right type of coverage and improve efficiency. Stretch wrap machines make it easy to quickly package even large shipments with consistency and reliability with the minimal manual effort required.
Overview of Production Process
The production process of the stretch film starts with the selection of appropriate raw materials. LLDPE, or Linear Low-Density Polyethylene, is the most commonly used stretch wrap material as it is highly flexible and durable. After sourcing the LLDPE, manufacturers will process it into pellets by melting down large pieces of the material. These pellets can then be mixed with other compounds such as tackifiers to achieve a desired level of stickiness. Once mixed, the pellets are extruded through a die to produce a uniform sheet of plastic film that has a specific thickness and width. The plastic sheet will then be passed through chill rolls where it is cooled off and hardened before being cut into strips or coils ready for packaging.
Once the wrapping process is complete, the coil typically gets rolled onto cores made from cardboard or plastic which makes them easier to transport and store until needed for use. Depending on their needs, customers may choose between different types of stretch film including hand stretch film, machine wrap as well as microwavable wraps for food packaging applications. Each type offers unique benefits such as increased puncture resistance or stronger adhesion when wrapped correctly around objects or pallets respectively.
Materials
A. Types of Polymers Used
1. Linear Low-Density Polyethylene (LLDPE):
LLDPE is the most widely used type of polymer in stretch film, providing an excellent balance between strength, puncture resistance, and flexibility. It is produced using a special process that results in a product with linear molecules with branches, which provide additional strength and elasticity. The increased strength and elasticity make LLDPE ideal for large rolls of stretch film.
2. High Density Polyethylene (HDPE):
HDPE stretch film is made from high molecular weight polymer chains, making it very strong and resistant to stretching or tearing. This strength makes it perfect for wrapping heavier loads, such as pallets full of boxes or large crates filled with products. HDPE also provides good clarity for barcode scanning and great protection against punctures and tears.
3. Metallocene Polyethylene (mPE):
mPE is made from a blend of polymers that have been treated with metallocenes (a special chemical) to make them much stronger than traditional plastic resins without adding any extra weight or thickness. mPE has excellent puncture resistance and outstanding clarity, making it ideal for protecting wrapped items while maintaining the visibility of barcodes or labels on the package surface during transit.
4. Blended Polyethylene:
Blended polyethylene stretch films are commonly used because they are economical yet still provide excellent tensile strength and cling properties when stretched around heavy packages or boxes being shipped. These blends combine different types of polymers to create a material with specific desired properties, such as higher tear resistance or greater elongation before breaking apart under stress or strain.
5. Ethylene Vinyl Acetate Copolymer (EVA):
EVA copolymer has great elongation characteristics and can easily wrap around objects without splitting apart due to its tear resistance capabilities. Together with its elastic memory capabilities, this makes EVA well suited for automating the wrapping process on packaging lines where speed and consistency are important factors in the performance of the machinery used to wrap products in stretch film.
6. Polyvinyl Chloride (PVC):
PVC stretch films are less common than other types but they offer some benefits over traditional plastic resins including good clarity and UV stabilizers that reduce deterioration from exposure to sunlight or extreme temperatures. While these films tend to become brittle when exposed to cold temperatures, they can be formulated with additives like plasticizers which improve their flexibility at lower temperatures so they don’t crack during usage or shipping in cold environments like wintertime climates
B. Additives Used
1. Paraffin Wax:
Used to improve the strength and durability of stretch wrapping, paraffin wax is added in small amounts to the plastic material during the manufacturing process. This helps create a stronger bond between the material’s fibers, providing better stretchability and preventing tearing. Paraffin wax also serves as an effective moisture barrier, keeping shipments protected from outside elements.
2. Polyethylene Resins:
Commonly used in high-grade stretch wrap films, polyethylene resins are a type of thermoplastic polymer that provides greater tensile strength and flexibility than other types of plastic materials. These resins are designed to be resistant to punctures and tears while still allowing for films to be stretched tightly around pallets or boxes. The polyethylene resins also provide superior clarity, allowing shippers to easily view their goods while still being assured they remain safe and secure throughout transit.
3. PVC Compounds:
To add additional abrasion resistance and tear strength, many stretch wrap manufacturers rely on PVC compounds during production. These compounds are formulated with special additives that make them resistant to extreme weather conditions such as heat or cold temperatures and windy environments, so shipments can remain secure no matter what conditions they’re exposed to during shipping.
4. Antistatic Agents:
Used when shipping electronics or other sensitive equipment, antistatic agents help keep static electricity from building up on the film’s surface by neutralizing the charge when it comes into contact with another object or surface. This helps reduce any potential damage caused by static discharges which could damage delicate electrical components inside packages during transit.
5. UV Inhibitors:
While most plastic materials degrade over time due to prolonged exposure to sunlight, some stretch wrap films are formulated with UV inhibitors that minimize this effect when exposed to direct sunlight for extended periods. These additives help maintain the integrity of wrapped items for longer periods, even if they’re subjected to harsh outdoor environments such as cargo placed on docks or in warehouses where UV rays may affect it over time otherwise
Manufacturing Process
1. Extrusion:
The process of extrusion involves pushing melted plastic through a die to create a thin, continuous sheet of film. This material is fed into an extruder, where it is heated and melted, before being forced through the die with tremendous pressure. This process is used to create films with specific thicknesses and widths.
2. Blown Film Extrusion:
After being pushed through the die by the extruder, the molten plastic moves through a bubble or tube, while air pressure forces it up and outwards against the die’s walls to form a cylindrical shape known as a ‘bubble’. The molten plastic then passes through an annular gap or nozzle where it cools down and solidifies, forming the desired film bubble or tube.
3. Air Ring Cooling:
Once the film has been created in its cylindrical shape, it needs to be cooled down for further processing. An air ring cooling system is used as part of this process; this consists of nozzles that emit jets of cold air at adjustable speeds from all sides of the cylinder which helps to reduce its temperature quickly and keep its shape unchanged throughout the cooling procedure.
4. Winding:
The cooled stretch film must now be wound onto spools for further processing and transport purposes; this is done using winding machines that rotate at high speeds, allowing for quick and efficient winding of large quantities of stretch film into rolls on different spools according to custom specifications such as size and weight requirements before packing in boxes or other containers for shipping or storage purposes.
Quality Control
A. Quality Control Tests Used
1. Moisture Content Test:
This test is used to measure the amount of moisture present in the stretch film and is conducted by weighing a sample of the film before and after it has been subjected to heat. The difference in weight can then be used to calculate the percentage of moisture content in the film.
2. Thickness Measurement Test:
The thickness of the stretch film is measured using a special gauge that determines how thick a sample of the material is when heated to a certain temperature. This test ensures that the stretch film meets industry standards for thickness and can provide additional information regarding its quality.
3. Puncture Test:
This test is used to determine how much force is required to puncture or penetrate through a sample of stretch film. A special device similar to an air pressure tester is used to measure this force, which helps ensure that the finished product will be strong enough for its intended use in packaging applications.
4. Tensile Strength Test:
This test measures how much force is required to pull apart or tear apart two samples of stretch film when they are placed under tension and then released simultaneously. The results from this test can help determine whether or not the material meets industry standards for tensile strength when it comes time for use in packaging applications.
5. Elongation Test:
This test measures how much a sample of stretch film stretches before it breaks or tears apart when pulled with increasing force over time; this indicates its degree of elasticity as well as its overall strength when put into practical use during packaging operations.
B. Meeting Industry Standards
Manufacturers of stretch films need to adhere closely to industry standards, both in terms of the quality control tests mentioned above as well as overall production requirements that must be met for their products to be accepted by end customers or during inspections by regulatory authorities such as those responsible for food safety regulations and other applicable laws related to product safety and efficacy. Quality control testing should also include regular inspections throughout all stages of production, starting with raw materials through every step until final delivery, including careful monitoring of all machinery used during manufacturing operations such as extruders, slitters, winders, vacuum formers, etc. Additionally, periodic tests should also be conducted on stored materials at regular intervals such as once per month or per quarter depending on storage conditions and shelf life considerations associated with the specific type(s) of material being stored or evaluated regularly during production operations like roll stock shrink wrapping machines or lay flat tubing machines used on automatic packaging lines where variance from established quality parameters may have an impact on product integrity and customer satisfaction levels down the line if problems are not caught early on during initial processing stages before final delivery occurs – mindful attention paid throughout all phases will ultimately lead towards higher quality assurance levels and better customer satisfaction ratings over time!
Conclusion
These are the basic steps of how the stretch film is made. Depending on the thickness or intended use, there may be additional steps involved in creating the perfect stretch film for your needs. However, this guide provides a general overview of the process so that you have a better understanding of what goes into making this versatile product.
