Stretch Wrap Films

• Stretch wrap loads are more secure which minimize shipping damages
• UVI stretch films can protect products stored outdoors from UV rays.
• Strong opaque films conceal load contents and reduce instances of pilferage
• Stretch films keeps products free of dust, moisture and dirt

• Stretch wrap film is more cost effective than alternatives such as strapping, corrugated or heat shrink film
• Stretch wrap equipment typically cost less than same caliber alternatives like shrink wrapping and strapping equipment.
• Stretch wrappers uses less energy to operate than other unitizing methods like shrink wrap systems.

• Increased packaging operation efficiency
• Improved Inventory control
• Increases worker productivity
• Scan-through optics
• Versatility of pallet load types

• Stretch film is recyclable. Learn how to start stretch wrap recycling see: Stretch Wrap Recycling - A How To Guide
• Learn how to save on tipping fees and make money recycling stretch wrap, see article: Plastic Stretch Wrap - In Big Demand

• Colour stretch films examples: tinted stretch wrap films, opaque white stretch film, opaque black stretch wrap, clear stretch wrap)
• Specialty stretch films examples: 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.

Types of Stretch Film - About:Stretch wrap packaging films

There are many types of stretch wrap film. Each has qualities that are particularly suitable in addressing the specific needs of your stretch wrapping operation, such as load size and type, performance requirements as well as budget. The following lists some of the most important types of stretch film, their attributes and applications. Click on a stretch wrap film below for details.

Blown Stretch Film Cast Stretch Film

Machine Stretch Film Hand Stretch Film

PreStretched Film Specialty Stretch Film

Cast Stretch Film
Cast stretch film also called cast film or cast wrap, is manufactured using the cast extrusion process. Typical characteristics of cast stretch films are: excellent optics, clear, glossy, superior tear resistance, quiet unwind, consistent cling and consistent film thickness. Cast stretch film products: hand stretch wrap film - cast, machine stretch wrap film - cast.

Blown Stretch Film
Manufactured using the blown film extrusion process and also referred to as blown film. Typical blown strecth film characteristics are: poor optics, hazy, dull, excellent puncture resistance, very noisy unwind and high force on load. See products: hand stretch wrap- blown

Hand Stretch film
Stretch film designed specifically to be applied manually is referred to as hand stretch film. It is also referred to as hand film, hand stretch wrap, hand wrap or manual pallet wrap. It is typically utilized in lower capacity packaging operations. However the efficiency of manual stretch wrap packaging should be regularly re-evaluated against potential benefits of upgrading to a machine wrapper. Choosing the right stretch applicator will result in more efficient and cost effective packaging operations. See products: hand stretch film - cast , hand stretch film - blown, prestretched hand film.

Machine Stretch film
Stretch film designed to be applied with a stretch wrap machine is referred as machine stretch film. It provides many advantages over hand film including: faster and more efficient packaging, reduced packaging material costs, safer application, more secure loads and more. Common machine stretch film types: cast machine stretch film, blown machine film and prestretched films. See products: machine stretch wrap film - cast and prestretched.

Prestretch films
Prestretched film is film that is stretched before wrapping a load. Prestretch film benefits include:

Specialty Stretch film
Specialty stretch films are designed to answer very specific packaging needs that more general purpose stretch packaging solutions cannot accommodate. A small sample of some specialty stretch packaging films are below, each are linked to a product details page.

UVI stretch wrap VCI stretch wrap Roll wrap film Wide web wrap Pallet wrap netting Pallet covers

Tinted stretch film Pallet stretch film Heavy gauge film Bundling film Vented pallet wrap Banding stretch film

Opaque black stretch wrap Anti-static stretch wrap Palletwrap adhesive Clear stretch wrap

Access Your Stretch Wrap Use

• Examine all applications of stretch wrap in the facility. Determine the quantity and types of stretch wrap being used, i.e., HDPE, LLDPE, LDPE, PVC and/or PP. Ask your supplier for data sheets on the film to be purchased.


• Note the quality of stretch wrap in the facility. Are there paper or plastic labels attached to the wrap? Is the wrap clear or colored? Is it free of dirt and grease?


• For each application, evaluate ways to reduce the amount of stretch wrap used in the facility. For example stretch wrap machines wrap pallets tighter and with less material. Pallet wrappers also can be trained to optimize film use.

Stretch film is made from high-grade polyethylene resin that is extruded into a very strong thin film. The film is then slit into specific widths and wound onto thick cores for shipping to the customers.

Should I use Cast or Blown film?

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 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 one-sided cling film is great where you don't want one pallet to stick to the one next to it. also, these film layers can make the film stronger by adding tough layers to the inside. cast film is also clearer and quieter coming off the roll.

Buying Guide - What to consider when buying stretch film

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 (see: opaque black stretch film)
• 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?

Stretch Wrap Calculations

• Easily calculate stretch film roll weight, roll length and film thickness conversion (micron : gauge). See stretch film calculator.
• 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.

Where to Buy Stretch Wrap film

• Buy Stretch Wrap Film wholesale directly from the manufacturer & Save your money!
  Polybags Limited are manufacturers and suppliers of polythene bags, stretch wrap film and packaging products. They supply Clear or Coloured Stretch wrap. Low Prices on the internet and Free U.K delivery!
  www.polybags.co.uk
• Discount Stretch Wrap
  Specialists in stretch packaging with great prices and discounts on clear stretch wrap, coloured stretch wrap and stretch wrap dispensers. Find the best suppliers and useful information about stretchwrap.

• Did you mean Shrink Wrap?

  Discount Shrink Wrap
  Experts in shrink packaging with great prices and discounts on shrink film, wrap, bags and shrink guns. Everything you need to know to help you choose the best type of shrink packaging for your needs.

Stretch Wrap Terms - Stretch film & stretch wrap packaging terms defined

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


• 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.


• 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.


• 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.


• 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.


• 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.


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


• LDPE Stretch Film
  Low Density Polyethylene Stretch Film


• LLDPE Stretch Film
  Linear Low Density Polyethylene Stretch Film


• 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.


• 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).


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


• 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.


• 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.


• 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. Also see: cling


• 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 teh 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.


• 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.

Stretch Wrap Packing Tips

PREVENTING DAMAGE

• most damage in moving comes from one item vibrating against another
• it pays to purchase the right packing materials to protect your valuables
• supplement bubble wrap and paper with blankets and pillows
• even clothing can serve as a buffer between breakable objects
• there should be no empty space in a box
• however don't overpack the box either
• use heavy-duty packing tape (not masking tape) for the boxes

CHOOSING THE RIGHT BOX

• a good packing job starts with strong, sturdy boxes
• boxes have a seal on the bottom that gives their strength and capacity
• indicates a weight limit and an "Edge Crush Test" rating
• 32ect is standard for most moving boxes
• 44ect is standard for most wardrobe and larger specialty boxes

PACKING TECHNIQUES

• keep the weight of your boxes reasonable
• put heavy items in small boxes to make them easier to carry
• double-box fragile items and add plenty of cushioning
• common sense is essential when loading the truck -- heaviest boxes on the bottom

APPLIANCES

• pack small appliances in original container or a box cushioned with packing paper
• do not use shredded paper -- it can clog the appliance
• check with major appliance dealer for any special moving instructions
• remove loose fittings and accessories on large appliances and pack separately
• pad exterior well
• tie down, tape, or wedge all movable parts and doors
• stuff towels between dishwasher or washing machine sides and tub to keep tub from rotating
• defrost and dry interiors of freezers / refrigerators well
• fill interior spaces with lightweight linens, clothing or stuffed toys

BEDS

• disassemble the bed frame
• tie rails and cross-pieces together with packing tape
• be sure to mark on tape to show where pieces fit together for reassembly
• protect your mattress and boxspring with a mattress cover or large sheets of plastic

OTHER FURNITURE

• fill bureau and dresser drawers with small breakable items and cushion well with loose clothes
• secure drawers with pad or blanket and tape
• do not overload drawers with heavy items
• wrap chair arms and legs to prevent scratches
• bundle armless chairs in pairs, seat to seat
• place a folded blanket or other padding between and tie seats together
• remove table legs and tie together
• put hardware in small sealed envelope taped to underside of table top
• pad tops, pad and tie spare table leaves
• for small tables, pad top and wrap legs to prevent scratching
• wrap your best furniture in bubble wrap, to protect from scratching
• also keeps dust and dirt off the upholstery
• stretch wrap can help to prevent small scratches and dust from damaging your furniture
• make sure to wrap the item very tight to prevent snags while you are moving

KITCHENWARE

• individually wrap each breakable dish, glass, etc. in packing paper or bubble wrap
• kitchen boxes will fit most kitchenware without making the box too heavy
• place saucers, plates and platters on edge
• DO NOT STACK FLAT
• cups and bowls may be placed inside each other and wrapped 3 or 4 in a bundle
• pots, pans, etc. can be stacked in a box with packing paper between them
• remember not to make the box too heavy -- someone has to carry it

OTHER HOUSEHOLD ITEMS

• extra large boxes best for packing light bulky items -- comforters, pillow, etc.
• can pack a few small fragile items in between the pilows for extra protection
• just don't forget they are there!
• put curtain rod hardware in a plastic bag and tape to rod or pack in dresser drawers
• disassemble lamps before packing
• pack small bases in dresser drawers surrounded by loose clothing
• pack large bases in boxes stuffed with packing paper or bubble wrap
• box shades individually in boxes with plenty of packing paper for stuffing
• don't use newspaper because it smudges
• small mirrors can be well wrapped in paper and packed in boxes
• for larger mirrors and large picture frames, frame boxes work best
• mark GLASS on the outside to prevent mishandling
• always pack and store on end
• after vacuuming rugs and pads, sprinkle with moth flakes
• roll up and tape

ELECTRONICS

• box radios and TVs upright and make sure items are well padded on all sides
• for console-size equipment, surround with furniture pads, then move and load upright
• separately pack stereo, CD, and cassette components
• pack in well-padded box marked FRAGILE
• pack CDs upright in their cases in a sturdy box with tape-reinforced bottom
• tie CDs in small bundles before packing, then fill air space with packing paper
• cassettes can be packed in a similar manner, although you can group them in larger bundles

CLOTHES

• dresses, coats, suits -- anything hanging -- travel best in reusable wardrobe boxes
• do not remove from hangers -- simply hang across rod in wardrobe box as is
• these boxes can also be used seasonally as "extra closets" for wardrobe storage
• ther clothes can remain folded in their regular dresser drawers
• large boxes can hold a lot of clothes without making the box too heavy

BOOKS

• they're heavy, so use medium boxes
• don't mix books with other items
• pack books flat, alternating bindings
• fill empty spaces with packing paper or bubble wrap

OUTDOOR EQUIPMENT

• loosen, lower and turn handlebars at right angles on bikes, carriages to save space
• clean and cover chains and pedals to protect other items from being snagged or soiled
• drain fuel and oil from lawnmowers before loading
• remove handle from hand mowers and place blade end in sturdy box
• drain garden hoses, coil and pack in boxes
• fill remaining space with lawn sprinklers, small garden hand tools, etc.
• combine rakes, shovels, and other long-handled tools together with tape
• don't move paint, gas, or flammables!
• the same goes for alcohol, solvents, lighter fluid, ammunition and greasy mops or rags

VALUABLES

• set aside jewelry, important papers and safe deposit box contents
• pack in a small container you can keep with you throughout the move

Stretch Wrap or Shrink Wrap - Clearing up the confusion

The majority of our customers who order stretch wrap call it shrink wrap and these are people who use the product daily. What hope is there for those who are not regular users of these products? And for that matter, who cares?

Well if you need one or the other, you should care and just about every industrial, commercial or distribution company uses these products. The last thing you need is to order a product that won't work for your application, especially in these time sensitive days. These are two very different products used for very different applications.

Let's clear up the confusion. 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. In some cases, shrink wrap is used for palletizing although it is far less common that stretch wrap for this application.

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.

Generally stretch wrap comes in 12', 15' and 18' sizes for hand wrapping and 20'-60' sizes for machine applications. Shrink wrap is available in most even number sizes between 4-20' and is generally 'center-folded', that is the film is folded over itself to form two layers. The product is inserted between the two layers and sealed on the remaining three sides, then shrunk by heat.

For more information on these products you can take a look at 'Stretch Wrap 101' at website www.polybags.co.uk

For more difference on stretch wrap and shrink wrap please refer below:

Shrink wrap is a packaging technique where the plastic film is wrapped around a product and heat sealed to form a loose envelope. It is then heated all over causing the wrap to shrink more or less tightly around the product.

Stretch wrap is an elastic film that is mechanically stretched around the product like a wide rubber band. It is not heat sealed but relies on a self adherence - so it is applied in plys; overlapped on itself.

To visualize the difference, a toy or a box of software might be shrink packaged. You can see the line of the heat seal that was made before the shrinking took place, but the print on the product is clearly visible through the film. The film is clear and relatively slippery.

On the other hand, a pallet or skid of boxes is stretch wrapped. A stack of shrink wrapped boxes of software might be stretch wrapped. The film used is a lot like, if not identical to, the household wrap which we use to call "saran wrap" ( it's usually not saran anymore). It is clear, but many wrinkles occur where the film overlaps itself so it is less appealing aesthetically.

Stretch wrap is therefore more of a shipping tool, while shrink wrap is more to keep a product clean until after it is in the hands of the customer.

There is lot of overlap in the function of the two products. Shrink wrap is also used to package cases of dog-food and other products shipped in bulk where the package is opened at the market and is not seen by the customer. Stretch wrap is used more and more to unitize small bundles for shipping.

Shrink wrap is an older technique preceding stretch wrap by more than 10 years. Before stretch wrap was used, shrink wrap performed many of its functions. It was soon discovered that stretch wrap was better than shrink wrap for heavy duty industrial packaging since it was no less effective and cheaper and easier to use. Shrink wrap is energy intensive since heat must be produced to shrink the film. The shrink machinery usually requires more maintenance since heat sealing of the film is necessary.

Stretch wrap film is designed to adhere to itself ( no adhesive is used though), The film has a high coefficient of friction. It can prevent a package from sliding when a stack of product is handled. The prevention of sliding may not be an asset when the high friction creates handling difficulties for people, or sliding difficulties for certain types of machine handling.

There are two major classifications of shrink wrap:

1. For 'point-of-sale' where the wrap has to sell the product - usually by not being in the way visually - rather expensive, special, oriented films are used. These films are very clear. When they shrink, they do so with alacrity, exerting energy on the product and shrinking with few or no wrinkles or distortion. This is hi-tech packaging where the film can be pre-printed with appropriate distortion so that the printing comes out perfect after it shrinks.


2. Industrial shrink packaging, on the other hand, is done with more ordinary films which are less costly and shrink,when heated, in attempting to regain the form it was in, in; or on its way out of; the extruder.

Stretch Wrap Recycling: A How to Guide

The purpose of this guide is to encourage and promote the recycling of a product commonly used by distributors in a wide variety of industries ' stretch wrap.

Stretch wrap is most commonly made of linear low density polyethylene, or LLDPE. Most of us know it as the material that secures pallets of individual containers. Pallet stretch wrap is used by product manufacturers and distributors to bind shipping cartons to pallets going to a warehouse/distribution center (W/DC). It is also used at the W/DC to wrap pallets sent to outlets/customers.

This guide takes you step-by-step through the design and implementation of a stretch wrap recovery program ' from locating markets and developing a collection system to assessing how a successful stretch wrap recovery program can affect your bottom line.

The guide is targeted primarily to firms with one or more W/DCs where products are received from manufacturers and then distributed to downstream outlets/customers. The fundamentals should assist any location receiving and unwrapping stretch film from pallets in developing a viable stretch wrap recovery program. Four case studies have been provided to demonstrate how a stretch wrap recycling program can be adapted to meet the needs of a given organization.

Why Recycle Stretch Wrap?

Stretch wrap is one of the largest components of a W/DC's waste stream. Those that do not recycle stretch wrap must pay to have it hauled away with the rest of the trash and disposed. A large W/DC can generate thousands of pounds of stretch wrap per year ' and that carries weight on the bottom line.

Recycling stretch wrap offers an attractive alternative to disposal. There are ready markets for clean material and many firms are especially interested in working with businesses. Also, stretch wrap is relatively easy to identify and recover. It arrives at the dock in a fairly clean, uncontaminated state. If kept that way, it has real market value. In fact, pound for pound, stretch wrap may be the most valuable scrap material a W/DC can recover.

For more information please click here.

Stretch Wrapping Pallets - Potential Hazards and Possible Solutions

Potential Hazards:

• After a load has been built, it is generally wrapped with plastic to maintain its integrity during transit.



Employees may be injured when performing this task manually.

They must bend at the waist to wrap the bottom of the pallets while supporting the plastic dispenser (Fig. 1)

• Employees often stick their fingers into the open end of the tubes to stream off the wrap.

This increases the risk of cuts to the fingers.

Possible Solutions:

• Use an automatic plastic wrapping machine with palletized product sitting on a turntable (Fig. 2).



This ensures the employee will not have to bend at the waist to wrap the pallet.

• If manual wrapping must be performed, use rolls that weigh as little as possible to minimize the lifting hazard.



A handle (Fig. 3) will prevent employees from placing their fingers into the tube, thus decreasing the risk of cuts.

News on Stretch Wrap

Stretch wrapper keeps its cool

Keeping cool in the summertime is a full-time job in Texas. Friedrich Air Conditioning, San Antonio, TX, provides assistance in this endeavor by manufacturing self-contained commercial air-conditioners (AC) for various types of installations, including temporary construction sites and standalone school buildings, to name a few. The unique air-conditioning units are taller than Shaquille O'Neal'more than 7 ft'and weigh up to 490 lb, providing a new packaging challenge for Friedrich.

The new air-conditioner line, the wall-mount series, was introduced in March, '00 and includes seven different models. Before this product introduction, Friedrich was packing smaller air-conditioning units in corrugated cases and did not own a stretch-wrapping machine. With help from distributor Pack-Mark, Inc., Friedrich bought an Orion FA-66 fully automatic, rotary turntable, conveyorized stretch-wrap system. The system features a 4,000-lb load weight capacity, a programmable logic controller (PLC) from Allen-Bradley, structural steel components and powered roller conveyors.

With all of the units in the wall-mount product line weighing more than 200 lb, Ralph Fuentes, manufacturing engineer for the assembly line at Friedrich, needed a stretch wrapper that could convey the large air-conditioners to the wrapping station in a reliable manner. Fuentes says, "The main attraction to the system was the relative ease with which the stretch wrapper conveyed the wall-mount units. The motorized, powered rollers on the conveyor are very sturdy, and I really like that the operator is not getting involved with moving these units in the stretch-wrapping area."

The air-conditioner, pictured at the top, measures 24 x 48 x 90 in. Orion customized the FA-66 with a 12-in. mast-height extension for wrapping the upper section of the tall units. Friedrich bought the machine in September, '01, but the stretch wrapper was not connected to infeed and outfeed conveyor lines at that time. In June, '02, the stretch wrapper was integrated with the infeed and outfeed conveyors.

Moving time

After the wall-mount air-conditioner unit undergoes final inspection (proper freon distribution within the unit), it is placed on a 25 x 48-in. wooden pallet. Due to the large size of the units, one resides on each pallet. From the inspection system, the air-conditioner rolls forward on a gravity-fed, metal-roller infeed conveyor to the first station on the packaging line, the corner-board application area. Here, an operator manually places double-wall, 200-lb corrugated corner boards around the four corners of the unit. Supplied by Gaylord Containers, the corner boards are affixed with tape to the 90-deg edges, providing protection during distribution.

The unit moves forward on the infeed conveyor'manually moved forward'after placement of the corner boards and approaches the FA-66's motorized conveyor system. At this point, the infeed conveyor rises approximately 14 in. to meet the stretch wrapper's conveyor. The infeed conveyor tilts downward, and the pallet slides forward. From there, the conveyor moves the pallet to the wrapping station.

At the stretch-wrapping station, the pallet is secured on the turntable. The film carriage, after being loaded with 70-ga polyethylene stretch film, moves vertically up and down a stainless-steel tower while the turntable rotates. The combination of these two actions creates the stretch wrapping action. The stretch film is supplied by AEP Industries. Friedrich's packaging line is able to stretch-wrap 20 to 30 units per day.

The FA-66 comes equipped with Orion's Insta-Thread' film-delivery system. The system provides simple loading of film into the carriage by opening a hinge that guides the film tail through to the rollers. Also, the Insta-Thread system provides prestretching of film to 245 percent by using two textured rollers inside the delivery system to stretch the film, with one roller turning faster. This prestretching cuts film After wrapping, the film's tail is cut using an impulse hot-wire. The pallet then moves to an outfeed conveyor. usage costs. Friedrich uses 84 ft of film for each unit, PD is told.

After the pallet is wrapped, it moves past a sensor that provides logistical information on the pallet to the PLC. From there, the wrapped pallet then travels 35 ft on an outfeed conveyor. At the end of the conveyor, a forklift operator picks up the unit and places it in storage.

For this new product introduction, Friedrich needed this "lift" to keep up with the new demands placed on its packaging operations. While shopping around for a stretch-wrap system, Fuentes saw an Orion video of the FA-66 and knew immediately that the system was the one to purchase, PD is told. With this successful installation and operations running smoothly, Fuentes and Friedrich feel cool as a cucumber in the Texas heat.

Lantech has success all wrapped up

Growing a small Louisville business into an industry-dominating global enterprise might seem a stretch, but stretch is what it's all about at Lantech.

The company pioneered using plastic film to wrap multipackage shipments into a tightly bound unit on a wooden pallet.

Brothers Pat and Bill Lancaster developed the concept at a kitchen table using rubber bands to visualize how plastic film could be stretched around stacks of boxes. It was an almost immediate success.

"It was such a better mousetrap," said Pat Lancaster, company chairman. "That's how a company with no money can get started."

Today, Lantech has 420 employees, 60,000 machines in the field and annual revenue of about $110 million. The company has more than 175 patents in packaging machinery, holds the dominant share of stretch-wrap machinery sales in North America and has strong sales in Europe, Asia and Australia.

"They are the best and everybody knows them, and they recognize how important they are to the industry," said Mark Matthews, vice president of marketing for packaging for Xpedx, a packaging equipment and supplies distributor.

The technology that Lantech invented can be seen in almost any warehouse and in big-volume retailers such as Sam's Club. (WMT) Boxes, bags and other containers are "unitized" onto a pallet for fast loading with a forklift.

About 80% of everything shipped arrives on pallets. And of that, 90% is bundled by stretch wrap, said Jim Lancaster, CEO and son of Pat Lancaster, who turned over the company reins in 1995 and now concentrates on research and development. Bill Lancaster sold his share in the1990s.

Before the Lancasters developed their technique, shippers worked with large shrink-wrap bags, which were heated to seal the plastic, Jim Lancaster said. Lantech was founded in 1972 to make and sell the ovens needed for the shrink-wrap.

But rising energy costs prompted the Lancasters to look for a different approach. With stretch wrap, they discovered, the plastic would stick to itself ' no heating required.

Also, the new method was cheaper and required less plastic. At the time, strapping cost $2 to $5 per load, and shrink bags cost $1.35 to $1.40. Stretch wrapping a pallet load cost $1 or less then ' and today is 25 to 35 cents per pallet load.

When the Lancasters made their discovery, shrink bags took 2 pounds of plastic to encase a loaded pallet. The first stretch machines cut that by half. The latest, out last year, can wrap a load of paper products with 3.5 ounces of film, and beverages with 4.5 ounces.

Lantech introduced its machines at a trade show and "for the next four years, our only problem was figuring out how to make them fast enough," Pat Lancaster said.

Lantech patented its stretch-wrap technique, but in 1989, a court stunned the company by voiding its primary patent. As royalty payments from other companies for using the technology dried up, it also became clear that production at Lantech's Louisville plant was ailing and it could lose out to competitors, Pat Lancaster said.

In response, the company switched to the "just-in-time" production methods pioneered by Toyota, which lowered costs and raised quality and delivery speed. The improvements were dramatic, Pat Lancaster said.

Innovation, quality and efficiency are "what allow us to stay competitive" when many manufacturers have shifted their work to low-wage nations, Jim Lancaster said. He added that the company's fastest-growing markets are China and Southeast Asia.

FAQ on Stretch Wrap

Find out Answers on Common Stretch Wrap Film Questions

• What Is Prestretch?
• Why Use Prestretch?
• How Is Film Prestretched?
• What Is Post Stretch?
• Benefits Of Post Stretch
• How To Post Stretch?
• What Is Film Force? (film tension)
• Why Have Film Force?
• How To Create Film Force?
• What Is Film Feed?
• How To Control Film Feed?
• Cost Reduction
• Protection
• Additional Benefits Of Unitizing

What Is Prestretch Film?
· A process that allows stretch film to be stretched before being applied.
· The stretch film is prestretched by two rollers. The second rollers rotational speed is quicker than the first, thus stretching the film between them.

Why Use Prestretch Stretch Film?
· STRENGTH
By stretching the film, the tensile strength of the film increase so that it becomes drastically stronger.
· FILM MEMORY
After the film is stretched it wants to return it to its original form. The more you use this prestretching process, the worst the film memory becomes.
When the stretch film is applied to a load with no force to load, quickly it will be able to detect that the film has tightened due to its memory as it tries to return to it original size.
Stretch film memory is what distinguishes stretch film from other means of packaging unitizing. Settling that can happen during shipment can loosen other methods of unitizing products. Stretch film memory takes up the slack and continues to secure the load during shipment.
· FILM ECONOMIES
Your cost of stretch film is reduced when it is prestreched compared to stretch wrapping a load with film that has not been.
· STRETCH CONSISTENCIES
Using just hand or machine to add tension to stretch film does not provide uniform stretch and is not able to have reliable performance. This type of stretching can lead to intermittent load failures.

How Is Film Prestretched ?
· When film is stretched mechanically between the film carriage rollers due to the gearing ratio and diameter of the rollers it is prestretched.

What Is Post Stretch ?
· The stretch in the film produced by the film tension between the film carriage and the load being wrapped, which is also known as force to load.
· If the film tension is increased the post stretch will be intensified.
Benefits Of Post Stretch
· PROS
Maximizes load retention of the film.
· CONS
This "Tension" stretch is generally on the corners of a load, which can cause damage too high.

How To Post Stretch ?
· The amount of film force applied is directly proportional to Post stretch.
· Increase film force and the post stretch will be increase.

What Is Film Force ? (film tension)
· The tension created in stretch film due to the films attempt to return to its original state after having been stretched.

Why Have Film Force ?
· Low film force restrains the film from returning back to its original state.

How To Create Film Force ?
· Film Force is formed by creating tension between the load and the film carriage that can be produced both mechanically and electrically.
· Electrically reducing the speed of the film leaving the carriage compared to what the load requires increases the stretch film force which causes the film to stretch between the load and the carriage.
· Mechanically postpones the dancer arm which measures the speed demand of the load will reduce the film feed leaving the carriage which increases the force.

What Is Film Feed ?
· Provide the stretch film required to wrap a load while keeping the tension of the film constant.
· The carriage must vary the supply of film with the demand of the load while the load revolves.
· A dancer roller reads the demand of the load.

How To Control Film Feed ?
· SENSOR: The stretch wrappers dancer arm rotates a cam shaft which sends a varying signal to the drive board then it sends varying voltage to the motor. The larger the dancer size the larger the output voltage. The larger the output voltage means the faster the film is fed.

Cost Reduction
· LOWER HANDLING COSTS
Unitizing products with stretch film, greatly decreases handling costs.
· LABOR SAVINGS
Handling of individual boxes is more time consuming than handling a unitized load. Another benefit of unitization packaged goods is the amount of man hours saved in the movement and shipment.
· TRANSPORTATION SAVINGS
Unitizing packaged goods increases the speed at which they are moved, carrier vehicles spend less time at docks. This time saved also offers valuable cost savings.

Protection
· SECURITY
Reduce the risk of pilferage and theft because packages are in a enclosed load and are complicated to remove. The loss of packaged goods is much easier to keep track of if they are shipped out in unit loads rather than individually, which reduces the occurrences of lost or stolen items.
· MINIMIZE IN PLANT DAMAGE
Stretch Film wrapped goods moved by forklift or pallet jack, are less likely to substain damage than loose boxes carried by hand. Moving a unitized load in a warehouse reduces the risk of product damage.
· MINIMIZE SHIPMENT DAMAGE
It is less likely in shipping that dense and or heavy items will be packed on top of palletized unit loads. You stand a greater chance of not being damaged because of this.

Additional Benefits Of Unitizing
· INVENTORY CONTROL
Unitizing products speeds up control of inventory since large unitized loads can be recognized, counted and managed more easily and individual boxes.
· CUSTOMER SERVICE
Unitizing products and goods for your customers allows them to offload and move goods through their warehouse more efficiently.