You have just purchased our big bag with loading valve and flat bottom—the professional format for bulk packaging of powders, grains, and binders in the plant—and this guide explains how to connect it to your filling line, load it, close it, and lift it safely. The inner liner and top valve require different handling than an open-mouth bag.
Below, you will find the technical specifications, the step-by-step procedure, recommended complementary products, and maintenance guidelines that will extend the lifespan of your big bag.
Product specifications
These are the technical characteristics that define this specific model and will allow you to quickly identify which units apply to your order.
| Specification | Value |
|---|---|
| SKU | 972400 |
| Material | Virgin woven polypropylene with UV treatment |
| Opening | Top loading valve compatible with hoppers and filling spouts |
| Bottom | Flat bottom |
| Inner liner | With liner (additional plastic barrier against moisture and contamination) |
| Dimensions | 90 × 90 × 100 cm (3 × 3 × 3.3 ft) |
| Payload capacity | 1500 kg (3300 lb) |
| Safety factor | 5:1 |
| Handles | 4 reinforced lifting loops |
| Color | Translucent white |
| Packaging | Pack of 30 big bags |
Step-by-step usage guide
Follow this procedure from the first time to integrate the bag into your operation safely and leverage the 5:1 safety factor it is designed with.
Inspect the bag before loading
Unfold the bag and check the seams of the handles, base, and top valve area. Verify that the inner liner shows no excessive wrinkles, perforations, or tears. The integrity of the liner is the barrier against moisture and cross-contamination; if damaged, replace it before packaging.
Position the bag under the hopper or spout
Center the big bag on a clean pallet and under the hopper outlet. Lift the four handles and secure them to the filling station guides; keep the bag vertical and stable. Unfold the top valve upwards to connect with the hopper spout.
Connect the valve to the filling spout
Fit the loading valve over the hopper's discharge tube or spout, ensuring it covers the entire circumference. In systems with a clamp, adjust it to seal the connection and prevent dust dispersion. Correct connection allows for packaging flours, cements, or pigments without environmental contamination.
Load in a metered and controlled manner
Activate the hopper discharge and load up to the target weight (maximum 1500 kg). Monitor the weight with a platform scale; if the system allows, program automatic cutoff when the target is reached. Keep the bag stable throughout the filling process for the flat bottom to form correctly.
Close the valve and prepare for lifting
Once the weight is reached, tie, knot, or seal the top valve according to the system (inner cord, clamp, or heat-sealing). Verify that the seal is watertight if it will be stored outdoors or for a long period. Check that all four handles are free and use a spreader bar or central hook to lift, distributing the tension.
When packaging cement or fine dusty materials, lightly moisten the outside of the valve with a cloth before connecting it to the hopper. This reduces static electricity that disperses dust during filling and keeps the packaging area much cleaner.
Compatibility with your packaging line?
If you need to confirm whether the standard 35-40 cm loading valve fits your hopper or if special measurements are required, ask the Dodom Virtual Assistant for a recommendation based on your equipment.
Complementary products
If your process also requires metered discharge into mixers, consider the big bag with loading and discharge valves. For volumes with coarse or irregular material that do not fit the valve, use the open-mouth model. Stretch film for machines secures pallets of several filled big bags with automated wrapping.
Maintenance and care
A well-maintained big bag can be reused for several cycles; one that is poorly stored will fail during the first lift of its second use. These guidelines are what will extend the bag's lifespan the most:
- Before reusing, completely empty the bag and check the condition of the inner liner. Replace the bag if the liner shows cracks, punctures, or non-removable adhered residue.
- Store empty bags in a dry area, without compression, and in the shade. Avoid the top valve being sharply folded for long periods; this can create permanent creases that make it difficult to connect to the hopper.
- Periodically inspect the valve area and the liner seams. Any tear here compromises the barrier against moisture and contamination.
Do not force the valve onto the hopper nozzle if it does not fit smoothly. A forced connection can tear the seam area, scatter material during filling, and ruin the bag for future cycles. If the valve does not fit, check the measurements with your supplier before proceeding.
Frequently asked questions
Can I use this big bag for product without a liner?
Yes, the inner liner adds protection against moisture and contamination, but it is not mandatory for all materials. If you are packing dry, non-hygroscopic, low-value product, the liner is optional. For cement, flours, salt, or moisture-sensitive products, the liner is highly recommended.
How much does the standard loading valve weigh?
The standard top valve is a woven polypropylene sleeve made of the same material as the bag. It does not add significant weight and typically fits hoppers with a circular nozzle of 35-40 cm in diameter. For different measurements, consult with the technical team.
Can I close the valve with any knot?
The closure depends on your line's system: manual knot with inner cord, mechanical clamp, or heat sealing. For prolonged storage or transport, use the most airtight method possible. A simple knot is sufficient for short cycles in the plant; for export, heat sealing or using a clamp is advisable.