Bulk Bag Filling and Discharge Spouts: Check Equipment Fit
FIBC selection for purchasing and production teams
Check both openings before the next bulk bag order.
A bulk bag can have the right body size and safe working load yet still need a different filling or emptying arrangement. The connection at each end deserves its own specification.
This guide helps Australian businesses compare open, duffle and spout tops, separate bag dimensions from spout measurements, and give suppliers the details needed to check equipment fit.
01 / Filling
Identify the inlet.
Record how material enters the bag and how the filling equipment connects. A top spout and a wide duffle skirt provide different openings.
02 / Emptying
Specify the outlet.
Confirm the bottom construction, discharge sleeve and closure. A spout-top bag can still have a closed base.
03 / Fit
Check the whole interface.
Bring the equipment model, connection dimensions and available clearance. Matching one diameter is only part of the assessment.
Start at the filling station
Open top, duffle top or filling spout?
Choose the top around the way material is introduced, the connection to the filling point and the required closure afterwards. Keep the material and operating environment in the discussion.
Open top
An open top gives broad access to the bag body. Consider it where the approved process uses open loading and does not require an integrated top closure.
Check the filling arrangement and how the contents will be protected through subsequent handling. An open mouth does not establish suitability for dusty or contamination-sensitive work.
Duffle top
A duffle, or skirt, provides a broad fabric extension that gathers for closure. It can suit a filling process needing a wide opening and a fabric top that can be tied afterwards.
Record skirt dimensions separately from body height. Check the actual closure instructions and whether a liner is part of the required specification.
Spout top
A filling spout is a defined fabric sleeve attached to the top panel. Compare it with the inlet, clamp or other connection specified by the filling-equipment supplier.
Request diameter, sleeve length and the attachment arrangement. The words “spout top” alone do not confirm that a bag will connect to a particular machine.
Build a useful dimensional record
Keep body size, spout diameter and sleeve length separate
A listing such as 90 × 90 × 120 cm describes the stated bag size. It does not describe a 90 cm filling opening or establish the length of the discharge sleeve.
Similarly, a 40 cm diameter × 50 cm height spout specification identifies two measurements of the sleeve. Preserve the supplier's wording and ask how each is measured, including whether the stated length includes any attachment or closure allowance.
When checking an existing bag, use an empty sample under your site's safe inspection procedure. Label photographs clearly: top, bottom, sleeve attachment, sleeve mouth and closure. Add the current bag label and SKU so a measurement can be matched to the correct product.
Clarify whether an opening measurement is diameter, circumference or width laid flat. These are different measurements. Ask the bag supplier to confirm the convention rather than transferring a flat-width measurement into a diameter field.
- Body dimensions
- Record the listed dimension order and units. Identify whether the source calls them internal, external or nominal. Keep skirt, spout and loop measurements separate.
- Filling spout
- Record stated diameter and sleeve length or height, measurement convention, material and closure. Include the filling-head specification.
- Discharge spout
- Record its own diameter and sleeve length, plus the closure and receiving connection. Check the outlet even when the inlet has the same listed dimensions.
- Liner and closures
- Record whether a liner is required, how it is retained and how its openings connect. Include petal covers, tie tapes and other specified closure details.
- Handling envelope
- Record filled height, loop arrangement, lifting equipment and clearances at both stations. Check the physical setup against the approved handling method.
Pacific Packaging Australia product examples
The same bag size can support different filling choices
These two active listings both state a 90 × 90 × 120 cm bag size and 1500 kg SWL. Their top configurations differ. The published detail also differs, so each needs its own equipment check.
Defined inlet and outlet
1.5 Tonne Spout Top Spout Bottom Bulk Bag
- Listed bag dimensions
- 90 × 90 × 120 cm
- Filling spout
- 40 cm Diameter × 50 cm Height
- Discharge spout
- 40 cm Diameter × 50 cm Height with Petal Closure
- Rating and use
- 1500 kg SWL; 5:1 safety factor; single-trip use
- Pack of 5 SKU
- SS90Z120(1)
Circular woven polypropylene construction with four cross-corner lifting loops. Compare both sleeves and the petal closure with the actual filling and discharge equipment.
View spout-top bag
Wide filling skirt and outlet sleeve
1.5 Tonne Duffle Top Spout Bottom Bulk Bag
- Listed internal bag size
- 90 × 90 × 120 cm
- Configuration
- Duffle Skirt Top, Spout Bottom
- Spout and skirt measurements
- Confirm the required dimensions with the supplier before ordering for equipment fit.
- Rating and use
- 1500 kg SWL; 5:1 safety factor; single-trip use
- Pack of 5 SKU
- DS90Z120(1)
Circular woven polypropylene with four cross-corner lifting loops. The current written specification does not state the discharge diameter or sleeve length. Keep those as open enquiry items.
View duffle-top bagProduct specifications checked on 5 November 2026. Pack quantities and SKUs above identify the selected ordering options. Check the current listing and confirm the full specification and availability before ordering.
The connection is part of the system
Check sleeve reach, clamping and material flow together
Send the equipment supplier the proposed bag specification. Ask them to confirm the accepted sleeve dimensions, connection method, available access and any liner requirements for the actual machine.
A useful manufacturer example is Flexicon's bulk bag discharger interface, which combines a spout clamp with a telescoping tube to manage the sleeve as a bag empties. Its description explains how excess fabric can create flow restrictions. This illustrates why sleeve length and connection design matter; it does not establish compatibility with a Pacific Packaging bag.
Before standardising the order
Run a documented equipment-fit check
Agree the assessment with production, the equipment supplier and the bag supplier. Begin with the specification and an empty sample, then use an approved trial plan for the actual material.
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Identify the existing setup
Record the current bag SKU, label, material, target fill mass, filling equipment and receiving equipment. Photograph both connections and note any problems the replacement should resolve.
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Resolve missing measurements
Request a specification drawing for the proposed bag and the equipment's connection requirements. Confirm diameter conventions, sleeve reach, skirt dimensions, closures and liner details before treating the shortlist as approved.
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Review an empty sample
Under the site's safe procedure, check the actual sleeve, closure and intended connection. Record access for connection and closure, fabric left at the interface and the equipment supplier's acceptance of the arrangement.
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Assess the complete cycle
Use the agreed trial method to review filling, closure, handling and emptying with representative material. Record connection difficulties, leakage, flow interruptions, residual product and any need for operator intervention.
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Measure the operational result
Compare connection time, discharge time and rework using the same material and agreed conditions. Keep bag cost, labour and product loss separate. Use measured results to support the purchasing decision.
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Retain the approved specification
Keep the SKU, drawing, pack quantity, equipment models and trial record together. Review the fit when bag construction, liner, machine or material changes, even if the body size and SWL stay the same.
Keep selection and handling aligned
Confirm closures, SWL and the handling method
FIBCA's safe handling guidance calls for the bottom discharge to be closed to the manufacturer's instructions before filling. It also requires people and body parts to remain clear beneath a suspended FIBC, and appropriate controls for dust and the operating environment.
Plan access to the outlet through a suitable, approved handling arrangement. Follow the bag and equipment instructions for connection, opening and closure. If a liner is specified, confirm its retention and closure as part of that process.
Keep the rated load in view
The two featured bags are listed for single-trip use at 1500 kg SWL with a 5:1 safety factor. The safety factor does not permit loading above the SWL or establish permission to reuse a single-trip bag.
ISO 21898:2024 covers FIBCs for non-dangerous goods. Its scope does not establish that an individual bag is certified or suitable for every product. Request the documentation needed for your application.
For the wider selection, see our FIBC bulk bag buying guide. Keep the opening-fit check alongside the bag's load rating, material requirements and approved site procedure.
Questions before a repeat or volume order
Bulk bag spout buying questions
Does every spout-top bag have a discharge spout?
No. Spout top describes the filling arrangement. The bottom can be closed or have its own discharge sleeve. Check both configurations on the selected product.
Are all bulk bag spouts 40 cm in diameter?
Use the exact product specification. The featured SS90Z120(1) option lists 40 cm diameter × 50 cm height at both ends. That detail cannot be transferred to another bag because its body size or load rating matches.
Can I choose a duffle top using the bag height?
Record the skirt measurement separately. For the duffle-top example, 90 × 90 × 120 cm is the listed internal bag size. Ask for the skirt dimensions and closure details needed by your filling process.
Will a larger discharge spout empty the bag faster?
Confirm performance with the equipment supplier and a representative trial. Opening size is one input alongside the material, sleeve arrangement and receiving equipment. This guide does not assign a discharge rate to any listed bag.
What should I send with a bulk bag equipment-fit enquiry?
Include the current bag SKU and label, material and intended fill mass, body dimensions, top and bottom configurations, spout measurements, equipment models and connection details. Add photographs, the issue to resolve, required quantity and delivery postcode.
Make the next enquiry specific
Match the bag to both ends of the process.
Compare the filling opening, discharge arrangement and complete specification before approving the next bulk bag order.
Bring the equipment details
Contact Pacific Packaging Australia with your bag label, connection measurements, material and required quantity. Those details give the team a practical starting point for confirming the available product information.
Explore the full FIBC and bulk bag range for other top and bottom configurations. Confirm final suitability with the people responsible for your filling, handling and discharge systems.