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When it comes to securing and protecting your packages for storage or shipping, stretch wrap is an indispensable tool. But did you know that there are two main types of stretch wrap – cast and blown? In this guide, we will explore the differences between these two types of stretch wrap and help you determine which one is best suited for your needs.
Cast and blown stretch wraps are two distinct processes to produce distinctive film types. The cast extrusion process starts with a granular resin fed into an intense, heated barrel containing a screw-like device that transforms the ingredients into usable plastic wrap. Blown film extrusion has the same beginning but ends differently; instead of coming out as one flat sheet, it comes out in hollow tubes filled up like sausage casings! Both methods lead to strong, long-lasting materials – make sure you choose wisely for your next project!
Packing materials are an essential part of the shipping process. To keep your items safe and secure during transport, you need to use a material that will protect them from damage. The most common packing materials are cast stretch film and blown stretch film. Cast stretch film is made from a mold, while the blown film is created through the blowing process. So what are the main differences between these two types of stretch wrap? Let’s take a closer look!
What is cast stretch wrap, and what is blown stretch wrap?
Cast stretch wrap film are the premium choice for businesses seeking reliable plastic film solutions. Using a cast extrusion process, these films boast superior cling and significantly lower force-to-stretch requirements than a blown stretch wrap film. Cast film also stand out in terms of higher tear resistance and quiet unwinding from machines. Blown stretch wrap film can come close in terms of its lower cost, but it cannot match the superior performance of cast stretch films. In light of this, businesses seeking reliable packaging options should carefully consider the advantages of switching to cast wrap films for their operations.
Blown stretch films effectively wrap and secure materials from impacts, moisture, or dirt. This unique plastic is made with a blown extrusion process that yields greater load-holding power than most other film types due to its higher mechanical properties. Air is blasted through the center of the die for the tube structure of this material to expand like a balloon – and then cooled by air rings on top – leaving you with more durable protection against transportation harm!
Creation Of Cast Stretch Wrap
Cast stretch wrap is a highly advanced film created using an innovative process. Resin beads are fed into a heated barrel and then forced through slots in the die, creating a thin sheet. This sheet undergoes cooling to solidify it while traveling along its rolling path, resulting in more outstanding production per hour than other methods like blown extrusion. Cast stretch wrap has advantages over regular wraps, with superior clarity, puncture resistance, and tearing strength. That makes it ideal for use even under humid or wet conditions where most films may absorb moisture quickly, otherwise making them unfit for usage!
The benefits of using cast stretch wrap
High transparency – This allows for goods to be easily seen through the film, which is helpful when trying to track inventory.
Excellent barrier for moisture, gases, and aromas – This prevents products from being affected by outside elements, ensuring that they are stored and shipped in the best condition possible.
Uniform thickness throughout – This ensures that the film will not be too thick or too thin in certain areas, providing a consistent level of protection for the products.
No limits on the thickness of the film – Unlike some other forms of stretch wrap cast, the stretch wrap can be made as thick as needed, providing an added layer of protection for sensitive products.
Cast stretch wrap has a very quiet unwind – This means that it does not produce a lot of noise when used, which can be helpful in areas where sound needs to be kept to a minimum.
Creation Of Blown Stretch Wrap
The blown film extrusion process creates the blown stretch film. The resin beads are fed through a heated machine with a circular die, then forced through the die and blown out vertically into a bubble. As this formed bubble finishes transforming into rolls of stretch film, it is cooled by the surrounding air. This type of film costs more because the output per hour is less than with cast films.
The benefits of using blown stretch wrap
1.Increased stability
When you use blown stretch wrap, you’ll find that your wrapped products become much more stable. This is because the wrap clings to the product tightly, making it less likely to move around or fall off during transport.
2.More protection
This type of wrap is thicker than a standard stretch wrap, so it’s better able to withstand bumps and other impacts. Additionally, the wrap’s clingy nature helps keep dust and dirt off your products.
3.Enhanced appearance
In addition to increased stability and protection, blown stretch wrap enhances your products’ appearance. The tight fit of the wrap gives your products a neat and polished look, which can help to increase sales.
4.Easy to use
Blown stretch wrap is also easy to use, which is another benefit. This wrap comes on a roll, so it’s easy to dispense and apply. Additionally, the clingy nature of the wrap means that it will adhere to your products easily.
5.Affordable
This type of wrap is typically less expensive than other packaging options, such as boxes or bags.
How to choose the right type of stretch wrap for your needs
1: Consider the type of material you need.
There are two main types of stretch wrap: plastic and paper. Plastic stretch wrap is more durable and moisture-resistant than paper, making it ideal for wrapping heavier items or items that will be stored for an extended period. Paper stretch wrap is more lightweight and breathable, making it suitable for wrapping lighter items or items that need to breathe (such as produce).
2.Consider the size and shape of your item.
If you are wrapping a large, bulky item, you will need a heavy-duty stretch wrap that can accommodate its size and weight. If you are covering a small, delicate thing, you will need a light-duty stretch wrap that will not damage the item.
3.Consider the storage conditions.
If you are storing your wrapped item in a humid or moist environment, you will need a moisture-resistant stretch wrap. If you keep your wrapped item in a dry climate, you will need a breathable stretch wrap.
4.Consider your budget.
Stretch wraps vary widely in price, so choosing one that fits your budget is essential.
When to use cast vs. blown stretch wrap
The ever-evolving world of stretch wrapping applications has made it challenging to decide when and where one should use cast stretch wrap or blown stretch wrap. In general, cast stretch wrap stretch easily and it is most often used for shorter loads that are more prone to dust, dirt and moisture. In contrast, blown stretch film is ideal for heavy loads since its extra toughness makes it more reliable for securing large items and protecting them from damage during transportation. Furthermore, blown stretch wrap stretches 200-300% compared to just 150-175% with cast films, allowing users to create optimal tension on the load during application. For added safety, while transporting, blown wraps typically range in thickness between 40 and 80 microns, while cast film range between 19 and 35 microns. Ultimately what makes the most significant difference and determines which type of film is best suited for any particular needs is the size, shape, weight, and destination of the palletized load.
Cast Stretch Wrap is an excellent choice for heavier and more sensitive items. Additionally, the quiet unwind of Cast Stretch Wrap makes it ideal for areas where sound needs to be kept to a minimum.
Blown Stretch Wrap is a better choice for lighter and less fragile items. The blown film extrusion process creates a thinner and more breathable film than the cast extrusion process, making it better suited for products that need to breathe. Additionally, Blown Stretch Wrap is an affordable option for packaging your products.
Which type of stretch wrap is best for you
By taking a few key factors into account, you can be sure to select the wrap that best meets your needs.
First, consider the type of surface you will be wrapping. If you are wrapping rare or delicate items, you will need to choose a wrap with a softer texture that will not damage the goods. Second, think about the level of protection you need. If you are wrapping goods for storage or transport, you will need a strong and sturdy wrap to keep them safe from bumps and scratches.
Finally, take cost into account. Some wraps are more expensive than others, but if you plan to use them regularly, it may be worth investing in a higher-quality product. By considering these factors, you can be sure to choose the right type of stretch wrap for your needs.
Cast stretch wrap is made with linear low-density polyethylene, while the blown stretch wrap is made with high-density polyethylene.
The significant difference between the two types of stretch wraps is that cast wrap clings to itself, whereas blown film does not. This means cast wrap will often provide a higher level of security for your items because it can be applied more snugly. However, in cases where you need to quickly apply and remove the wrapping (such as when packaging frequently shipped items), the blown stretch wrap may be the better option since it is easier to work with.
