FIBC Discharging Options and Bottom Designs

The discharge system must suit the product’s flow behaviour, the receiving equipment and the operator’s method of opening and controlling the outlet. Powder fineness, tendency to bridge, batch size and the need for complete or metered emptying should be defined before the bottom construction is selected.

Common FIBC Bottom Options

• Flat bottom: a closed base for applications using an external opening or cutting method approved by the customer.
• Discharge spout: a cylindrical outlet sized around product flow and receiving equipment.
• Protected discharge spout: a cover, flap or petal-style closure can retain and protect the tied spout during transport.
• Double discharge spout: an outer component can protect a separate inner outlet or liner spout.
• Full-open discharge: a large bottom opening for selected bulky or difficult-flowing materials.
• Conical bottom: a shaped base can assist gravity flow for applications where product remains in conventional corners.

Design Around the Process

Provide the receiving hopper opening, required discharge rate, clearance, operator access, flow-control method and whether the product tends to compact, bridge or flood. The outlet diameter, length, ties, lock, protective cover and liner connection are then recorded in the approved specification.

Discharge Safety

The filled FIBC must be supported by equipment designed for its load. Personnel should not work beneath a suspended bag or place themselves in an uncontrolled product flow path. Remote or assisted opening systems can be considered where process risk assessment requires greater separation between the operator and the outlet.

Reference Framework

For non-dangerous goods, ISO 21898:2024 covers FIBC materials, construction, design, type testing, marking, selection and safe use. Electrostatic classification for FIBCs used in hazardous explosive atmospheres is addressed separately by IEC 61340-4-4:2018. Dangerous-goods applications require the applicable transport rules and an approved UN design type. The final approved specification and handling label govern the supplied FIBC.

Define Your FIBC Requirements

Complete the specification form and send it to info@elayplastic.com.