Stretch Wrap - Basic Q's and A's

Do I need Shrink Wrap or Stretch Wrap and what's the difference?

Most people who order stretch wrap from us call it shrink wrap; but the products are very different. Shrink wrap film is made from polyolefin plastic, while stretch wrap is made from polyethylene plastic. Shrink wrap is generally used to protect a single product, such as the plastic over toys at the toy store or CD's when you first buy them. Shrink wrap gets its tight seal through a heating process. The product is wrapped and heated with a hairdryer-like tool or put through a heat tunnel. Shrink wrap can also be used for bundling products together, such as bottles of soda. We supply both stretch wrap and shrink wrap.

Stretch wrap is generally used to hold boxes on a pallet for transport. Stretch wrap is pulled around the load and stretched. The plastic has a memory and wants to return to its original size. This "elastic band effect" holds the load tight.

Ok, now I know the difference between Stretch Wrap and Shrink Wrap, what are the key features of Stretch Wrap?

Since its early introduction in the early 70’s, stretch film has become the most important method of unitizing product loads for transport. There are a number of key features for this including:

The uniform and relatively high holding force that stretch film applies to a load
The protection from dust and damage it provides versus other unitizing methods
The optics that allow for customers and shippers the ability to identify the product while also keeping it clean
It is the most economical method of unitizing

Why is some film called CAST and some BLOWN? Is this plastic or gum?

Originally, all stretch wrap was blown, a process much like blowing bubble gum. Resin is heated and passed over an opening through which air is blown. Most state-of-the-art film today is cast. It is extruded through rollers and "laid out" in sheets. This process allows the film to be made in multiple layers. The layers allow the film to be made with cling on only one side. This optional one-sided-cling film is great where you don't want one pallet to stick to the one next to it. Also, these films layers can make the film stronger by adding tough layers to the inside. Cast film is also clearer and quieter coming off the roll. Our film is all cast film.

What is a mil and what does it mean to stretch wrap? What does 80 gauge mean?

A mil is simply a measurement of thickness. One mil is one thousandth of an inch. So .80 stretch wrap is .8 thousandths of an inch thick. 80 gauge is the same as .80 mil. That sounds pretty thin, but 80 gauge or .80 mil thick stretch wrap is great for most applications.

Why are there so many sizes? What do I need?

First, are you applying the stretch wrap by hand or with automated equipment? If you are stretching the film by machine, you will generally use a film over 20" high and 5000 or 6000 feet long. These rolls are heavy -- about 32 lbs. Since that's a little too much to carry around a pallet, most people use 18" x .80 x 1500' rolls to stretch their pallets by hand. If your skids are not very high or if you just need to wrap the top and bottom of the loads, you could use 15" or 12".

I've seen stretch wrap used to bundle things like millwork, plastic pipe and small boxes. What's that?

This is bundling stretch wrap. It's used like tape, but it won't stick to the product or leave residue. This wrap comes in 2-6" sizes.

Can I use stretch wrap for covering my food?

NO!!! Stretch wrap is not made for food contact and this industrial product should be kept away from children. Like any plastic, it can be dangerous.

Is stretch wrap recyclable?

Yes, stretch wrap can be recycled through many local and state recycling centers

Types of Stretch Wrap

Do I need Shrink Wrap or Stretch Wrap and what's the difference?

Ok, now I know the difference between Stretch Wrap and Shrink Wrap, what are the key features of Stretch Wrap?

Since its early introduction in the early 70’s, stretch film has become the most important method of unitizing product loads for transport. There are a number of key features for this including:

The uniform and relatively high holding force that stretch film applies to a load
The protection from dust and damage it provides versus other unitizing methods
The optics that allow for customers and shippers the ability to identify the product while also keeping it clean
It is the most economical method of unitizing

Why is some film called CAST and some BLOWN? Is this plastic or gum?

What is a mil and what does it mean to stretch wrap? What does 80 gauge mean?

Why are there so many sizes? What do I need?

I've seen stretch wrap used to bundle things like millwork, plastic pipe and small boxes. What's that?

This is bundling stretch wrap. It's used like tape, but it won't stick to the product or leave residue. This wrap comes in 2-6" sizes.

Can I use stretch wrap for covering my food?

NO!!! Stretch wrap is not made for food contact and this industrial product should be kept away from children. Like any plastic, it can be dangerous.

Is stretch wrap recyclable?

Yes, stretch wrap can be recycled through many local and state recycling centers

Stretch Wrapping Benefits

Stretch wrapping is one of the most popular unitizing and pallet wrapping methods on the market today. The following lists some of the main benefits of stretch wrap

Cost Reduction

LOWER HANDLING COSTS

In general, whenever a load of packaged products increases in quantity, size & weight, the cost per unit handled becomes lower. Unitizing products therefore, significantly reduces handling costs.

LABOR SAVINGS

Without exception, the handling of loose boxes is more "time intensive" than handling a unitized load. Thus, another benefit of unitization is the amount of man hours saved in the movement and shipment of packaged goods. The end result is a quicker flow of goods throughout factories, warehouses and cross dock operations while utilizing fewer hands

TRANSPORTATION SAVINGS

Since unitizing accelerates the speed at which goods are moved, carrier vehicles spend less time at loading docks. This reduction in loading time provides valuable cost savings to the company which unitizes as well as the customers receiving the unitized products.

Protection

SECURITY

First, unit loads reduce incidents of pilferage and theft because packages from an enclosed load are difficult to remove.Moreover, unit loads are much easier to track than individually packaged products, making the "disappearance" of goods more detectable.

MINIMIZE WAREHOUSING DAMAGE

Unitized loads moved by forklift or pallet jack, are less likely to suffer damage than loose boxes carried by hand. Moving a unitized load throughout a warehouse minimizes the risk of product damage, for instance, a small carton or box may receive impacts from 30" or higher when accidentally dropped by hand, a unitized load will seldom receive 12" in drop.

MINIMIZE TRANSIT DAMAGE

It is less likely in LTL shipments that dense, heavy items will be parked on top of palletized unit loads. Hence, your goods stand a greater chance of not being damaged. The same cannot be said of cartons shipped individually.

Additional Benefits

INVENTORY CONTROL

Unitizing products facilitates improvements in control of inventory since large unitized loads (as opposed to parcels of smaller ones) can be identified, counted and managed more easily.

CUSTOMER SERVICE

Customers appreciate the effects of unitizing because it allows them to unload their trailers and move goods through their warehousing systems more efficiently.

Why Unitize With Stretch Film ?

LOW SUPPLY COST

Compared to other packaging and bundling materials, stretch film is the lowest cost to use because it offers the most yield for the dollar.

PROTECTION FROM MOISTURE, DIRT & ABRASION

Stretch film protects against these elements, safeguarding the goods it wraps.

RELIABLE PEFORMANCE

The security associated with holding performance and protection is readily evident. The holding power of other packaging materials such as adhesives can be deceiving. They unravel, loosen or come undone without being noticeable a few minutes or hours after application.

FLEXIBLE

The very nature of Stretch Film is flexibility. Inherent Properties of Stretch film allow for Economy by variable controlled " Pre-Stretching" and Load Integrity with variable controlled "Post- Stretching".

AUTOMATION

Stretch film machines are either partially or fully automated, which improves the productivity of the packaging process, reduces labor and alleviates back-breaking and time consuming work.

SCAN-THROUGH OPTICS

The clarity of stretch film enables UPC codes to be quickly scanned and read while protecting labels and lot codes printed underneath the film.

EASE OF REMOVAL

Stretch film only clings to itself and not surfaces, making its removal fast,safe,clean and easy.

ELIMINATION / REDUCTION OF OTHER PACKAGING MATERIALS

Stretch film's superior load holding capability either eliminates the need for or helps scale down the bulk of other packaging materials.(e.g. In some cases stretch film may enable thinner corrugate to be used for packaging goods)

RECYCLING

Stretch Film is recyclable.

VERSATILE

Stretch wrap films come in a wide variety of standard and special attribute blends to address many stretch wrap packaging application needs. Two examples include: Colour Stretch Fims and Speciality Stetch Fims.

Colour stretch film types: tinted stretch wrap films, opaque white stretch film, opaque black stretch wrap, clear stretch wrap
Specialty stretch film types: uvi stretch films, vci stretch films, heavy gauge films, roll wrap films, bundling film, banding film, wide web pallet wrap, vented stretch wrap, stretch wrap netting, pallet covers and top sheeting film, anti-static stretch wrap and more pallet wrap solutions.

Stretch Wrap Buying Criteria / Guide

The following represent important criteria to consider when choosing a stretch film to meet your specific unitizing requirements.

Stretch Film Application

What is the required level of hold force retention?
Will load require greater puncture resistance or tear resistance?
Is load value high or low? Ex: High value loads may need to conceal contents?
Is shipping distance short or long and by what method?
Storage conditions. Ex: If Long term outside, may need UV stretch film.
Does product require a specialty stretch film? (Such as: uvi stretch films, vci stretch films, heavy gauge films, roll wrap films, bundling film, banding film, wide web pallet wrap, vented stretch wrap, stretch wrap netting, pallet covers and top sheeting film, anti-static stretch wrap, etc).

Stretch Equipment & Operation

Will packaging operations require a quiet unwind film machine film (ex: cast) or very high decibels of noise is tolerable (ex: blown)?
Is higher production speed, stabler loads and cost efficiency important?
Will film need to allow scanning of bar codes or reading of labels?
What size and gauge of film is required?

The Stretch Wrapped Load

What is the pallet /load profile (ex: height, weight)?
What is the Load Stacking Pattern (ex: column, interlocked, mixed)
Is the load profile type A, B or C?

“A” Profile : These loads are typically cubed with no protrusions and relatively clean. These are the easiest loads to wrap.

“B” Profile : These pallets may have an object protruding or do not have clean vertical sides but rather an irregular sides. The puncture hazard may require a better performance film.

“C” Profile : These pallets have a very irregular load with many corners, sharp edges, or protrusions and are difficult to wrap. A higher performance stretch film will be required to handle this type of difficult load.

Stretch Wrap Calculations

Stretch film specifications for common machine film and hand wrap (microns per gauge, roll weights per gauge, case weights per gauge). See stretch film quick reference.

For more information on stretch film buying criteria, stretch wrap products, stretch wrap equipment, pallet wrap, other unitizing products and industrial packaging supplies, contact us today!

Stretch Wrap Packaging Equipment Basics

What Stretch Wrap Equipment is Right for YOUR NEEDS?

Generally operations wrapping 15 or more pallets a day will find it beneficial to move from manual stretch wrap application to automated stretch wrap packaging machines. Today's new stretch film and stretch wrap equipment technology allows any packaging operation to gain the production speeds, cost efficiency and higher quality stretch wrap packaging solutions that were previously only attainable by much larger packaging operations.

For greater stretch wrap packaging capacity the following types of stretch wrappers can be used. These units can accommodate low to very high capacity packaging operations:

Turntable, Low Profile, Semi-Automatic
Turntable, High Profile, Semi-Automatic
Conveyorized Turntable, Automatic
Rotary Tower, Semi-Automatic
Rotary Tower, Automatic

By using the right stretch wrap machine your busines will achieve the optimal production efficiencies and cost saving benefits that stretch wrap offers. For stretch packaging equipment solutions, that you can buy, lease or rent, we have you covered! We offer a complete line of stretch packaging equipment.

For more information on stretch packaging equipment systems, stretch wrap, special application stretch film, pallet wrap or for other industrial supply or packaging material solutions, contact us today!

Stretch Wrap Standard Measurements & Charts

Standard Stretch Wrap Gauge, Weight and Roll Lengths:

Machine Film		Hand Wrap
Microns Per Gauge
Gauge	Microns	Gauge	Microns
50	12.7	49	12.5
51	13	51	13
57	14.5	53	13.5
59	15	55	14
60	15.2	57	14.5
61	15.5	59	15
63	16	61	15.5
65	16.5	63	16
67	17	65	16.5
69	17.5	67	17
70	17.8	69	17.5
71	18	70	17.5
73	18.5	71	18
75	19	73	18.5
77	19.5	75	19
79	20	77	19.5
80	20.3	79	20
83	21	80	20.3
85	21.5	81	20.5
87	22	83	21
89	22.5	85	21.5
90	22.9	87	22
91	23	89	22.5
100	25.4	90	22.9

Roll Weights Per Gauge
Hand Wrap
Gauge	Feet	Pounds
50	9000	36
55	8000	35.2
60	7500	36
60	8000	38.4
65	6000	31.2
65	6500	33.7
70	6000	33.6
75	6000	36
80	5500	35.2
80	6000	38.4
90	5000	35.2
100	4500	36
115	3500	32
135	3500	37.8

Roll widths vary as follows: *406mm/16" **325mm/330mm *** 330mm/338mm,

Case Weights Per Gauge
Hand Wrap
Gauge	Feet	Pounds
51	2476	19.3
55	2000	23.2
63	2476	18.8/19.3
65	2476	20/20.4

Stretch Wrap Terminology and Definitions

Banding:

Applying multiple wraps of stretch film to reinforce a specific area of a pallet or to band together multiple units.

Product example: banding stretch film

Blown Film:

Stretch films manufactured by the blown film extrusion process are called blown films. Stretch film extruded by the blown method typically produces greater puncture resistance but less aesthetic values than cast films.
Product example: blown hand stretch film

Bottom Wraps:

The rotations a stretch wrap machine makes applying stretch film to the lower portion of a unitized load. Bottom wraps of more than one rotation augment pallet stability.

Cast film:

Stretch films manufactured by the cast film extrusion process are called cast films. Stretch film extruded by the cast method typically have greater tear resistance, greater aesthetic values and are quiet to unwind, which is not typically found in film manufactured by the blown method.

Product example: machine cast stretch film, hand cast stretch films

Cling :

Cling provides the sticking to self but not to the product attribute. Films will be designed as a single side cling or a two sided cling. The cling bonding agent is typically added in as a single side or two sided layer in the co-extrusion process.

Co-extrusion:

The process of taking materials that are; fed, melted and or pumped in through other extruders, which are then merged to create a multi-layer film.

Dart Drop:

A technique used to measure the impact strength or sturdiness of a film; this is ascertained by dropping a crescent shaped weight (aka dart) onto a film.

Elastic Recovery:

When the stretch film is stretched, strained and / or deformed its ability to recover and return to its original form indicates its elastic recovery capacity.

Elmendorf Tear:

A testing means for measuring a materials ability to resist tearing forces. This method initiates a tear in a sample material, then measure to the amount of force needed to tear the sample apart. Test result value is referred to as the tear value.

Extruder:

A piece of equipment hat uses mechanical and thermal actions to change solid polymer into a molten polymer.

Extrusion:

A manufacturing process that takes materials from one or more extruders, the resulting extradates are then configured to the fabrication of the end product.

Film Feed:

The speed at which the film is supplied to the load is the film feed. Film feed rate adjusts as needed on load corners to maintain consistent film tension.

Film Force:

As the film is applied the rate of tension in the film is called the film force or film tension. The rate is usually measured in pounds.

Film Memory:

Is the memory of the stretch film trying to return to its original un-stretched form and in the process makes the load tighter and more consistently secure. This prevents loosening of the load that can occur later as the load settles. To achieve optimal film memory and film efficiency, proper film and application settings are essential.

Film Tail:

The film tail refers to the start and end pieces of stretch film that are initially applied and then later cut off from a pallet in the stretch wrapping process.

Gauge:

An imperial measurement used to measure stretch film thickness or caliper. An example value would read as: 70 gauge, 80 gauge or 100 gauge. Also note: Often used as a synonym for film thickness.

Gloss:

Refers to a surfaces shine or sparkle, in LDPE stretch films it refers to the amount of light that is reflected from the stretch films surface. High gloss attributes are typically found in cast stretch films.

Product example:Product example: machine cast stretch film and hand cast stretch film

Hand Film:

Hand stretch film used for manual stretch wrap packaging application. Designed for hand wrapping application, hand film rolls are lighter and smaller than machine film rolls to make application easier. Also known as hand wrap, hand stretch wrap and hand stretch film.

Product example:hand stretch film

Haze:

Refers to lack of clarity and inability to see through a film, it is measured by the percentage of light not transmitted through a film sample. Characteristic is typical of blown stretch films.

Product example:blown stretch film and hand blown stretch film

Impact Strength :

The capability of a stretch film or other material to defy rapidly applied destructive forces.

LDPE Stretch Film:

Stands for 'Low Density Polyethylene Stretch Film'

Product example:stretch films

LLDPE Stretch Film:

Stands for 'Linear Low Density Polyethylene Stretch Film'

Product example:stretch films

Product example:

Machine Direction:

Refers to the direction perpendicular to the film width. Acronym: MD.

Machine Films:

Also referred to as Machine films, is stretch film designed for stretch film equipment.

Product example:machine stretch films

Metallocene:

New polyethylene resins developed using "Metallocene" change the polytheylene chain structures resulting in a new breed of stretch films. Metallocene stretch films can achieve increased puncture resistance and clarity while blends offer balanced film properties and universal stretch percentage applications (ex: machine film, hand film).

Product example: machine stretch films and hand stretch films

Microns :

Microns is a metric measurement used for measuring film thickness. One micron is equal to one millionth of a meter.

Also see: standard stretch film sizes, weights and gauges

Neckdown:

Neckdown is when a film losses its dispensing roll width / breadth and narrows down while being stretched. Neckdown reduces coverage each wrap provides thereby making it likely that more wrap rotations and more film will be needed to wrap a load or pallet.

Overwrap:

Refers to the amount of stretch film applied over the top of load. Overwrap provides a downward force on a pallet load and is often used to secure a pallet top sheet or corrugated top cap in place.

Pallet Covers:

Poly film covers commonly used to protect pallets from dirt, dust and/or conceal pallet contents.

Product example:palletizing products, pallet covers and sheeting film

Poststretch:

Poststretching is stretching a film by using the load to pull the film out at the same time as it applies film. Although this allows for the benefit of film tension, the tension levels are inconsistent and as such can damage many load types. Attempts to attain higher tension stretch can be done but can increase risk of damaging some load types and increase chances of stretch film breakage.

Prestretch:

Prestretching is stretching the film prior to application. The process can increases film strength, improve load integrity, reduce amount of stretch wrap film needed and save on stretch film packaging costs. Today many stretch films are designed to achieve optimal prestretching values that can be attained with leading edge high performance stretch wrap machines as well as prestretched films for manual application operations.

Product example: machine stretch films and hand stretch films

Roping:

Bunching the stretch films full width to create a rope is known as roping. Stretch film roping is extremely strong and is often used to further secure a pallet to its load. Bunching stretch film is a feature function of many stretch wrap machines (ex: turntable stretch wrappers).

Tackifiers:

Additives used in the material fabrication process to increase the "tack" of the film or material.

Tear Resistance:

Refers to the resistance of the film to tear. Attribute is quantified by measuring the force needed to propagate an initiated tear.

Tensile Strength:

Tensile strength a measurement of the maximum amount of force a material can take without breaking. The greater the tensile stretch measurement, the stronger the material.

Tension stretch:

Tension stretch is a pulling force that stretches materials. For example: stretching a rubber band will make it longer, as it gets longer its tension increases. Also referred to as poststretch.

Transverse Direction:

Refers to the direction across the stretch film web. Also referred to as TD.

Wide Web :

A specialty sized large film roll designed for equipment that wrap using larger widths.

Product example:wide web pallet wrap

Yield Strength:

The amount of stress a material can withstand without permanently having plastic deformation. Prior to reaching the yeild point a material will elastically deform but will return to original shape once the stress is removed.

Zippering:

Refers to the lack of resistance to of an initiated TD tear or cut. Once initiated, the tear will rapidly spread.

10 Reasons to Stretch Wrap

10 Reasons to replace Hand Wrap with a Stretch Wrapper for your Pallet Wrapping Applications.

Have you ever asked yourself if hand wrapping is the most cost effective, fast and safe way for your packaging applications? We can give you at least 10 reasons why it is not, and that is time for a Stretch Wrapper! (However, we do also carry a full line of hand held stretch wrappers for those who prefer or need to hand wrap).

1. Consistent and uniform application:

An operator who wraps pallets with hand wrap stretch film is not able to wrap every load exactly the same way, time and time again. A load wrapped by one operator Monday morning will not be wrapped the same way as another operator on Friday afternoon.Pallet wrapping with a stretch wrap machine eliminates this issue.

2. Professional Appearance:

Wrapping a pallet using a stretch wrap machine produces a clean professional finished product. Pallet wrapping with hand wrap leaves a rather erratic and uneven look. The look of your pallet load on your customer’s floor must project the professional image you want for your company. Pallet wrapping with a stretch wrap machine eliminates this issue.

3. Training:

There is a right way and a wrong way to wrap a pallet with hand wrap. Applied incorrectly, hand wrap may crush the product or allow the product to shift during transport. Employee turnover or multiple operators mean that you must continually train employees on how to correctly wrap the loads to ensure customer satisfaction while ensuring they do not injure themselves. Pallet wrapping with a stretch wrap machine eliminates this issue.

4. Employee Safety:

Hand wrapping pallets is an extremely difficult job if it is done correctly, and a common source of employee back injuries when performed incorrectly. The human form is not designed to walk hunched over manipulating an 8-10 lbs weight while also trying to pull enough tension into the film to hold the pallet load together. Then 20 seconds later you are holding the same roll of stretch film above your head to do the top of the pallet, again tugging on the film using only your back and arm muscles. Many accidents and work related injuries are caused by hand wrapping pallets. Review OSHA (Occupational Safety & Health Administration) stretch wrapping guidelines before making your pallet wrapping decision. Pallet wrapping with a stretch wrap machine eliminates this issue.

5. Load Integrity:

No one likes hand wrapping. At some point the “good enough” syndrome takes over. Knowing what is required to keep your product unitized during shipping, and while it is on your customer’s floor, is essential in setting your stretch wrapping specifications for your operator’s to follow. When an employee is hand wrapping pallets the responsibility of meeting minimum tension requirements is left up to him. Fatigue, ignorance, training, or lack of motivation can affect the employee’s “good enough” point resulting in potential complaints or damage due to poorly wrapped product.Pallet wrapping with a stretch wrap machine eliminates this issue.

6. Damage Control:

As employees deal with the difficulty of hand wrapping the goal becomes just wrapping it enough to get it out the door. Wrapping the load to eliminate damage during transit and at your customer’s warehouse becomes secondary. Pallet wrapping with a stretch wrap machine eliminates this issue as it wraps the same way every time reducing the potential of a pallet being damaged during transit.

7. Customer Satisfaction:

Pallet wrapping your product is the LAST operation you perform and the FIRST operation your customer sees of your capabilities as a supplier. Your customer’s perception of your competence as a supplier starts the minute your pallet of product arrives at his dock. Inconsistently hand wrapped pallets can give the perception of a low-end manufacturer. Lowering your standards of production during this last operation can be costly. Pallet wrapping with a stretch wrap machine eliminates this issue.

8. Film Savings:

Although the key to stretch wrapping is to make sure that we get the product to the customer intact, we all want to do it for the least amount of cost. With the machine set to wrap the loads with the least amount of stretch film required to hold the load together, you eliminate unnecessary extra revolutions of film being applied by well meaning operators. At a point, more film does not hold the load better, it is just waste. Pallet wrapping with a stretch wrap machine eliminates this issue.

9. Damaged Hand Wrap Rolls:

An expensive hidden cost of hand wrapping is the cost of all the rolls of stretch film that are thrown away because they have been nicked or damaged when thrown to the ground or left lying around. This cost can sometimes be as much as 15-20% of your hand wrap costs. Pallet wrapping with a stretch wrap machine eliminates this issue.

10. Quality Control:

By definition, hand wrapping a pallet manually prevents you from obtaining any type of repeatability. Multiple operators, time of day, fatigue and many other variables prevents any type of QC standards. Pallet wrapping with a stretch wrap machine allows you to either eliminate, or preset these variables. This ensures repeatability, allowing loads to be wrapped to a set quality standard. Pallet wrapping with a stretch wrap machine eliminates this issue.

As you can see there is no easy way to hand wrapping. Eliminating any one of these issues justifies pallet wrapping with a stretch wrap machine. Let us show you the right Pallet Wrapper for your stretch wrapping application. Contact us today to talk to one of our stretch wrap specialists!