When dust escape, restricted discharge, bag leaning, or equipment-connection problems occur, the cause is not necessarily a general “bag quality” issue. Many problems result from a mismatch between the material, filling equipment, spout dimensions, liner, lifting belts, and storage conditions.

A practical troubleshooting structure is:

Problem → Possible Cause → Bag Configuration to Check

On-Site Troubleshooting Table

Problem 1: Dust Escapes Around the Filling Spout

Possible Cause

Material entering the bag displaces air. If there is no suitable route for the air and fine particles, dust may escape around the equipment interface, folds in the filling spout, or sewn connections.

Possible causes include:

• Filling spout substantially larger than the equipment outlet;
• Spout cannot be secured with a clamp or tie;
• Equipment outlet is not aligned with the bag center;
• Filling rate exceeds the capacity of the venting or dust-collection system;
• PE liner is not connected correctly;
• Uncoated or damaged material around the top panel;
• Open areas around seams or folds.

Bag Configuration to Check

Compare the measured equipment-outlet diameter with the effective internal spout diameter. A Ø45 × 60 cm filling spout has a 45 cm diameter and 60 cm length, but overlap and fastening still require confirmation.

Also inspect the coated top, PE-liner position, closure method, and need for an enclosed connection or separate dust-extraction system. Coated fabric can limit dust escape through woven openings but cannot correct an unsecured equipment interface.

Problem 2: Slow or Incomplete Discharge

Possible Cause

Discharge difficulty is not always caused by outlet size. Nickel sulfate particle size, moisture condition, compaction, and flowability also affect emptying.

Possible causes include:

• Moisture-related agglomeration;
• Powder bridging above the outlet;
• Twisted liner blocking the discharge path;
• Mismatch between the outlet and receiving equipment;
• Downstream equipment cannot receive material at the actual discharge rate;
• Pallet or bottom construction obstructs the outlet.

Bag Configuration to Check

Check the outlet diameter, length, and connection to the downstream hopper. A Ø45 × 45 cm outlet provides a 45 cm diameter path, but actual discharge performance still depends on material flowability.

Where bridging occurs, the outlet, liner arrangement, or assisted-discharge equipment may need adjustment. The bag bottom should not be cut open as an improvised method of increasing the discharge area.

Problem 3: Uneven Tension Across the Lifting Belts

Possible Cause

Bag leaning during lifting can be caused by twisted belts, partial loop engagement, off-center material, or unsuitable forklift-fork spacing.

Using only one or two loops concentrates the load on part of the lifting and seam structure. Sudden lifting, stopping, or turning may further increase load differences between the four points.

Bag Configuration to Check

Inspect the number and position of the lifting belts, loop height, and cross-bottom structure. The reference configuration uses four 7 cm wide cross-bottom belts positioned along the corners, with an approximately 45 cm loop height.

Confirm that the forklift can engage all four loops and that no belt is folded or positioned near a fork tip. Stop lifting if the belts are cut, seams are loose, or the filled bag leans visibly. Do not adjust the belts while the filled bag is suspended.

Problem 4: Bag Deformation or Excessive Footprint

Possible Cause

Filled-bag shape is affected by bag dimensions, material bulk density, filling height, and bottom support. Warehouse or pallet planning based only on empty-bag dimensions may not allow for lateral expansion.

Other possible causes include:

• Actual bulk density differs from the design data;
• Filling weight exceeds the confirmed value;
• Filling equipment is not centered;
• The pallet does not support the complete bottom;
• Bags are compressed during side-by-side storage;
• Material settles again during transportation.

Bag Configuration to Check

Review the relationship between target weight, bulk density, and effective bag volume. The 93 × 93 × 105 cm value represents nominal finished dimensions, not guaranteed maximum filled dimensions.

Pallet, warehouse, and transportation planning should use a filled sample. Where shape control is important, record the maximum filled length, width, and height during sample approval.

Problem 5: Spouts Do Not Fit the Equipment

Possible Cause

Equipment-interface problems often occur because only the equipment name was provided during purchasing, without actual diameter, connection length, or installation-height measurements.

Even matching nominal diameters may not provide sufficient room for fabric thickness, clamps, or the specific interface design.

Bag Configuration to Check

At the filling side, confirm:

• Equipment-outlet outside diameter;
• Effective connection length;
• Clamp or tie position;
• Filling-station clearance;
• Whether the PE liner connects separately.

At the discharge side, confirm:

• Receiving-hopper inlet dimensions;
• Required outlet insertion depth;
• Discharge connection method;
• Complete or partial discharge;
• Enclosed or dust-controlled connection requirements.

Spout dimensions should be based on measured equipment data rather than automatically copied from a previous order.

Problem 6: The Liner Does Not Provide the Expected Isolation

Possible Cause

Adding a PE liner does not automatically create a completely moisture-proof or leakproof package. The liner may become folded, twisted, punctured, or incompletely closed during installation, filling, or transportation.

An unsuitable liner size can also cause excessive stretching during filling or blockage around the discharge outlet.

Bag Configuration to Check

Check:

• PE-liner material;
• Liner dimensions and thickness;
• Whether the liner is fully extended;
• Tying or heat sealing at the top;
• Attachment to the filling and discharge spouts;
• Electrostatic compatibility between the liner and outer bag;
• Storage duration and ambient humidity.

The reference configuration uses a 200 × 340 cm PE liner with an approximate thickness of 90 μm. This does not by itself prove suitability for every humidity level or extended sea transportation.

Problem 7: The Package Does Not Fit the Pallet or Warehouse

Possible Cause

Storage-fit problems are often identified only after filling because the initial plan used nominal dimensions without allowing for lateral expansion, pallet edges, forklift aisles, or vehicle-door clearance.

Bag Configuration to Check

Before ordering, confirm:

• Nominal empty-bag dimensions;
• Maximum filled dimensions;
• Pallet length and width;
• Forklift-entry direction;
• Warehouse vertical clearance;
• Required bags per row;
• Truck or container internal dimensions;
• Stacking requirements.

A fixed stacking level should not be stated without a filled-bag sample or relevant stacking tests.

Troubleshooting Sequence

When leakage or handling problems occur:

1. Record whether the problem occurred during filling, closing, handling, storage, or discharge;
2. Identify whether it is concentrated around a spout, seam, lifting belt, or liner;
3. Measure both the equipment interface and FIBC spout;
4. Check whether particle size, bulk density, flowability, or moisture condition changed;
5. Compare the actual filling weight with the original specification;
6. Inspect the liner for twisting, damage, and incomplete closure;
7. Confirm that all four lifting loops are engaged evenly;
8. Recheck the pallet, warehouse, and transportation space with a filled sample;
9. Provide site photographs, equipment dimensions, and material data to the supplier;
10. Confirm structural revisions and sample validation before the next production batch.

Troubleshooting should identify where the material, equipment, and FIBC configuration no longer match instead of automatically increasing fabric weight or replacing one component.