What Is a Pallet Wrap?
A pallet wrap—also called stretch film or stretch wrap—is a highly stretchable plastic film primarily made from polyethylene variants like linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), or high-density polyethylene (HDPE). It is used to tightly secure and stabilize goods stacked on a pallet for transport and storage. Pallet wrap holds items together, protecting them from shifting, contamination, dust, moisture, and even theft attempts by creating a tight, tough barrier around the load. The film can be applied either manually by hand or via specialized wrapping machines.
How to Wrap a Pallet Correctly
Wrapping a pallet effectively is crucial to ensure load containment and prevent damage during transit:
- Preparation: Use a strong, undamaged pallet sized appropriately for the load. Stack products tightly, distributing weight evenly with heavier items on the bottom.
- Securing the Film: Attach the start of the wrap by threading film around a corner or tying it securely to the pallet or products.
- Base Wrapping: Wrap around the base of the pallet 3-5 times to lock the load to the pallet and prevent sliding. Cover the bottom 30-50% of the pallet wood to avoid the risk of film tearing when forklift prongs are inserted.
- Layering Upwards: Continue wrapping upwards, overlapping at least 50% of the previous layer for good coverage and strength. Maintain firm tension in the film to hug the load tightly.
- Top and Downward Wrap: Stretch the film over the top corners and wrap downwards slightly before finishing the wrap to secure the entire load firmly.
- Finishing: Tear off the film and tuck or stick the end firmly to avoid loose tails. Test stability by gently pushing the top items—they should not move.
Consistent tension and coverage around the top, middle, and bottom are key to effective containment force, which is the hugging pressure that prevents load movement.
Differences & Ideal Use Cases for Pallet Wrapping Patterns
There are several wrapping patterns, each with distinct benefits:
- Spiral Wrap: The film spirals continuously around the pallet from bottom to top (or vice versa). This is the most common pattern and provides good vertical and horizontal containment for uniform loads.
- Cross Wrap (Crisscross Wrap): Layers are wrapped in a crisscross pattern, alternating direction between layers. This increases lateral stability and is good for fragile or irregularly shaped loads, reducing shifting and spreading containment force.
- Skirt Wrap: Often deployed as an added layer around the base or as an external cover, a skirt wrap can protect against dust and moisture while also improving load stability. It’s distinct from regular film wrap and sometimes custom-printed for branding or security.
Choosing the right pattern depends on load shape, fragility, and transportation needs. For delicate or uneven loads, cross wrapping offers superior stability, while spiral wrap suits uniform pallet stacks for efficiency.
Pros and Cons of Hand Wrapping vs. Machine Wrapping
Hand Wrapping:
- Advantages: Lower upfront costs, high flexibility, portability, and suitability for small operations or varied load sizes.
- Disadvantages: Inconsistent tension and coverage quality due to human variability, more labor-intensive and time-consuming, higher film waste, and increased risk of weak spots and damage.
Machine Stretch Wrapping:
- Advantages: Consistent tension and coverage, stronger and more secure wraps, higher speed and efficiency, reduced labor costs in high-volume use, less film waste due to controlled stretch.
- Disadvantages: Higher initial investment for equipment, less flexible for oddly sized or positioned loads, requires maintenance and space.
Choosing between these depends on operational scale, budget, and load requirements.
Choosing Film Thickness and Type: Blown vs. Cast, LLDPE vs. HDPE
- Thickness: Typical pallet wrap thickness ranges between 12 to 35 microns. Thicker films offer higher durability and puncture resistance for heavy or sharp-edged loads but are less stretchable and more costly. Thinner films are economical and easier to stretch but less durable.
- Blown Film: Made through blown extrusion, noted for higher toughness, puncture, and tear resistance due to slower cooling and molecular structure. Best for sharp-edged or heavy loads needing robust protection.
- Cast Film: Made through cast extrusion, faster to produce, offers better clarity and cling but is less durable than blown film. Suitable for lighter, more uniform loads.
- Material Types:
- LLDPE (Linear Low-Density Polyethylene): Offers excellent puncture resistance and flexibility, making it the most common choice for stretch wrap, versatile for varied load shapes.
- HDPE (High-Density Polyethylene): Most durable, high tear resistance, best for very heavy or abrasive loads but less stretchable.
- LDPE (Low-Density Polyethylene): Less durable, often used in blown films but not as strong as LLDPE.
Stretch Tension Guidelines
Optimal stretch tension is vital to secure loads without tearing the film:
- Apply enough tension to create firm containment force (the hugging pressure) that locks the load together and to the pallet.
- Typically, stretch film can be safely stretched 100% to 300% of its original length depending on the film type and quality.
- For hand wrapping, aim for 30-50% film stretch to balance stretch and tear-resistance.
- Machine wrapping can control tension precisely; use data or trial testing to determine the ideal tension considering load type and weight.
- Avoid overstretching which leads to tearing or breaking; inadequate stretch results in loose, unstable loads.
Testing load stability by manually pushing ensures enough tension was applied without damage to the film.