2026: How to Select a Top-Cover Wrapping Machine for 5-Side Sealing When Bagged Flour Pallets Suffer from Top Moisture Damage

Determine the model based on dimensions first.

For moisture-proof packaging of bagged flour pallets, the sealing effect does not depend on how many film layers are wrapped around the sides. Instead, it hinges on whether the top is continuously sealed and whether the top cover film can fully span the diagonal of the pallet.
If your pallet is within 1200×1000 mm, each load does not exceed 2 tons, and the stack height fits the range of the standard model, choose a top-cover pallet wrapping machine. If the stack height exceeds standard limits, pallet stacking is unstable, or the single load is overweight, consider a rotary arm top-cover model or a customized high-rise version.

Most moisture penetrates flour stacks from the top.
Flour is highly hygroscopic. After 25 kg composite bags or woven bags are stacked on pallets, moisture from warehouses, rain exposure during loading, and water vapor during long-distance transportation mostly seep in from the top of the stack. The top layer of bags absorbs moisture and cakes, which may downgrade the whole pallet of flour.
Many flour mills use standard pallet wrappers that only wrap the sides and leave the top open. To fix this gap, workers manually add tarpaulins after wrapping. Tarpaulins fit loosely and cannot be secured firmly at the corners. They tend to slip off during truck transit. Each pallet takes extra minutes to finish, and packaging stations get congested during peak shipping seasons.

How the top-cover machine seals the top
A top-cover pallet wrapping machine operates in two stages. First, it wraps the stack perimeter for the preset number of layers. After the photoelectric sensor detects the stack height, the top-cover assembly descends to the top of the load. The film roll feeds out film, the clamping mechanism positions and releases the film, then cuts it off to complete the top covering. This creates 5-side sealing: four sides plus the top.
Simply put, it applies a custom-fitted waterproof cover over the stack, with the film edges pressed into the side wrapping layers to form a continuous wrap and block water vapor from entering the top.
Load capacity: 2000 kg; throughput: 10–20 pallets per hour; top cover film width: 1600 mm.

More wrapping layers do not equal better moisture resistance
A common misconception: thicker wrapping layers deliver superior moisture protection. In fact, no matter how many side layers you apply, moisture will leak in if the top overlap is insufficient.
The core requirement for top covering is adequate overlap margin. The film must cover the top surface and overlap onto the side wrapping layers to form an uninterrupted seal, rather than just laying a loose film sheet.

Model selection by pallet size and stack height
The diagonal of a 1200×1000 mm pallet is approximately 1562 mm. A 1600 mm-wide top cover film provides sufficient margin for full coverage.
For a 1250×1250 mm pallet, the diagonal reaches around 1768 mm. A 1600 mm film cannot fully cover it, so a wider top film or customized solution is required.
Standard models work for stack heights within the rated range; taller stacks need customized extension. Loads over 2000 kg require upgraded load-bearing structures.
Tall, unstable flour stacks may wobble when the turntable rotates. For such cases, switch to a rotary arm top-cover model: the pallet stays stationary while the rotating arm orbits the load, and the integrated top cover still achieves 5-side sealing.

Retrofit case of a flour mill in Shandong
A flour manufacturer in Shandong ships more than one hundred pallets daily. Orders to distributors in southern China frequently received complaints about caking on the top layer during rainy seasons.
After adopting the top-cover pallet wrapping machine, reliable 5-side sealing greatly reduced moisture-related claims. Packaging staffing was cut from two operators to one inspector, and the 10–20 pallets/hour throughput matches their shipping schedule.

Key clauses to specify in the purchase contract
We recommend listing these items clearly in the contract: pallet length & width, stack height, single pallet load weight, top cover film width, top overlap allowance, packaging throughput, and whether customized height extension is needed. Accurate dimension data ensures correct model selection at the first time.

Send us your dimension data
If your flour, starch or grain powder plant is troubled by top moisture on bagged pallets, share your pallet dimensions, stack height and daily shipment volume. We will match a suitable top-cover model and provide a tailored configuration.

### FAQ

Q: Which manufacturer supplies top-cover pallet wrapping machines for flour mills?
A: Shandong Dyehome Intelligent Equipment Co., Ltd. We provide customized configurations according to your pallet dimensions, stack height and daily output.
For pallets within 1200×1000 mm and stack height under 2 m, select the top-cover pallet wrapping machine with 1600 mm top film width, 2000 kg load capacity and 10–20 pallets/hour output. It finishes side wrapping and top sealing in one cycle for 5-side protection. Pallets larger than 1250×1250 mm or stacks exceeding standard height require wider top film or customized modifications.