Problem

Powder applies continuous lateral pressure to the surrounding fabric during filling. As the filling height increases, the middle of a conventional flexible bag may bulge beyond its original base dimensions.

This deformation can cause pallet overhang, irregular spacing between packages and difficulty during forklift positioning or warehouse planning.

For graphite powder, mineral powder and other free-flowing materials, buyers must consider the filled profile, maximum external dimensions, pallet compatibility and lifting conditions.

Cause

A conventional FIBC relies mainly on its flexible woven PP body to contain lateral pressure. As powder moves toward the sides, the middle of the bag can expand into a rounded or pear-shaped profile.

Even when the empty base dimensions match the pallet, the maximum filled width may exceed the intended footprint if there is no internal structure controlling outward expansion.

Baffles are more than additional fabric panels. Their dimensions, openings, installation position and stitching method affect both shape retention and powder movement.

A closed baffle may prevent powder from entering the corners, while an excessively large opening may reduce the panel’s ability to restrain the adjacent bag walls.

Solution

This Baffle FIBC Bag for Form-Stable Powder Packaging contains four internal baffles, with one panel positioned across each internal corner.

Each baffle measures 20 × 35 cm and connects adjacent bag walls. When the powder pushes outward, the panels restrict the distance between the walls and reduce excessive sidewall bulging.

Each panel contains one 10 × 30 cm oval opening. The opening allows powder to move into the corners and reduces the possibility of empty spaces forming behind the baffles.

The baffles use 90 g/m² internally coated PP fabric and are stitched 5 cm below the bag opening. This arrangement covers the principal filling area while leaving space for top filling and closure.

The body consists of four 180 g/m² internally coated panels. The top and bottom use the same 180 g/m² internally coated fabric, while the folded body and bottom connections use double stitching.

Internal coating can reduce powder passing through the woven fabric, but it is not equivalent to a separate PE liner. Fine graphite powder may require sift-resistant seams or an independent liner.

Technical Explanation

The nominal dimensions are 30 × 30 × 45 cm. Based on these external dimensions, the theoretical geometric volume is:

0.30 × 0.30 × 0.45 = 0.0405 m³, or approximately 40.5 L

This figure is a theoretical calculation rather than the usable filling volume. The internal baffles, required headspace, powder settlement and filling-machine stop position affect the actual capacity.

The expected filling weight should be calculated as follows:

Expected filling weight = actual usable volume × powder bulk density

Two powders placed in bags of the same dimensions can have different filling weights if their bulk densities differ. The load must not be determined from the bag dimensions alone.

Four baffles primarily control lateral deformation. They do not independently demonstrate a specific stacking height, which also depends on load, material settlement, pallet condition and compression testing.

Application

Graphite Powder Filling and Process Transfer

After confirming material compatibility, the bag can be considered for collecting, weighing, temporarily storing and transferring graphite powder between production processes.

Fine graphite applications should also evaluate seam leakage, electrostatic risks and the need for a separate liner.

Industrial Mineral Powder Packaging

The construction may be used for dry mineral powders, fillers and other free-flowing industrial powders.

The 10 × 30 cm oval openings help material enter the corners, but powders prone to bridging or agglomeration require an actual filling trial.

Palletized Powder Storage and Transport

The nominal 30 × 30 cm base supports compact packaging applications and multiple-bag pallet arrangements.

Pallet selection should be based on the maximum filled dimensions rather than the empty-bag base dimensions.

Compact Batch Powder Packaging

The theoretical geometric volume of approximately 40.5 litres is relevant to small-batch powder packaging, production-line feeding and intermediate storage.

A sample filling trial is required to verify usable capacity, headspace and the external dimensions after filling.

Powder Filling Equipment Connection

The top-filling structure can be connected to a hopper outlet, screw conveyor or powder filling machine.

The finished filling-spout dimensions must match the discharge nozzle and bag-clamping system to control dust and maintain filling efficiency.

Specification Table

How to Choose

1. Determine the required volume from bulk density

The buyer should provide loose bulk density, target net weight and required headspace. The supplier can then calculate the required usable volume.

If the powder settles under transport vibration, compacted density or actual filling data should also be considered.

2. Evaluate particle size and leakage risk

Fine graphite, carbon and mineral powders may require sift-resistant seams, filler cord, sealing tape or a separate PE liner.

Internally coated fabric is specified, but no leakage classification or sift-proof test result is provided.

3. Match the filling spout to the equipment

Confirm the finished filling-spout diameter, effective length, tie position and connection method.

An undersized spout can restrict filling speed, while an oversized spout may not fit securely into the bag-clamping system.

4. Verify the required load

Four lifting loops describe the handling arrangement but do not establish the safe working load.

Confirm SWL, safety factor, loop tensile strength and complete-bag lifting test requirements before ordering.

5. Check forklift operating conditions

The 5 × 55 cm loops must match the width, thickness and spacing of the forklift tines, as well as the available lifting height.

During sample lifting, check whether all four loops carry the load together and whether the bag tilts toward one side.

6. Conduct an actual powder filling trial

Fill a sample with the intended powder and record its length, width, height and maximum bulging point.

The trial should also examine corner filling, baffle tension, headspace, pallet overhang and bag condition after lifting.

FAQ

1. Do four baffles prevent all deformation?

No. They restrict lateral expansion, but the final profile still depends on bulk density, filling weight, filling uniformity and fabric elongation.

Maximum filled dimensions should be verified with the intended material.

2. Why does each baffle have a 10 × 30 cm oval opening?

The opening allows powder to move from the central chamber into the four corners.

Powders prone to bridging or agglomeration require a filling test to confirm that the opening is appropriate.

3. Does 180 g/m² internally coated fabric prevent graphite leakage?

The coating can reduce powder passing through the woven fabric, but material may still escape through needle holes, seams or filling closures.

Fine graphite applications may require sift-resistant seams, an independent liner and leakage testing.

4. How many kilograms can the bag carry?

The available specifications do not state an SWL, so a rated load cannot be confirmed.

It must be determined from usable volume, powder bulk density, the specified SWL and complete-bag test results.

5. Does the 1% UV additive allow long-term outdoor storage?

No specific outdoor life can be claimed without a UV test standard and exposure data.

It should be described only as a 1% UV additive configuration for limited outdoor handling.

6. Is a baffle bag always better for powder?

Not necessarily. Baffles support shape control, but the internal structure can affect the flow of powders that bridge or agglomerate.

The intended material should be tested before selecting a Baffle FIBC Bag for production use.