Ten things you should know before you purchase bulk bag discharge equipment

Thursday 11 December, 2014

Ten things you should know before you purchase bulk bag discharge equipment

Have you made the decision to have bulk materials delivered in bulk bags and are looking for discharge equipment to handle the product in a safe and effective manner?

For over 50 years, Guttridge have been helping customers to improve their conveying and discharging systems and specialise in the design of tailor made solutions for a wide range of industries and materials. We offer a range of specialist bulk bag handling systems that can include integral weighing, conveying or elevating, ideal for feeding storage silos, filling machines, dosers, reactors and other processing applications.

For easier, trouble-free sourcing of this equipment read our top ten tips of things that you need to know before contacting a supplier.

1. Assess supplier experience for your industry and application

It is no longer practical to go to a local fabricator to manufacture a simple bag support frame. Modern practices and legislation demand high levels of safety, containment and optional features offered by specialist suppliers with years of experience gained from real life applications and their own test facilities.

2. Define how the machine will be loaded

It is important to determine in advance how the bulk bags will be loaded. If a fork lift will be required, consideration must be given about whether it can be used in the area where the discharger will be located and if it will be available for use every time the bag is empty and needs replacing.

Systems are available using an integral hoist which negates the need for the fork lift truck. Replacement bulk bags can be brought to the discharge area with a pallet truck.

3 Focus on layout and existing equipment

The space available for the system can also drive the design options.

  • One major limiting factor is the available headroom where the discharger is to be positioned. Guttridge have a range of discharger and conveyor option to maximise the available space, including the available height and the material transport distances required.
  • Exact details of the bulk bags themselves are needed. Bags usually have an outlet spigot, for which diameter and length will be required. However the bags can be single trip bags (flat bottomed) requiring cutting before the contents can be discharged, or for very difficult products a full base discharge bag may be used, which requires. specialist discharge equipment.
  • Some bags may be fitted with a loose internal liner which requires the chosen discharge system to include a tensioning system to ensure consistent discharge of the product.
  • Bag design and dimensions including loop length are important and should be given to prospective suppliers at the earliest opportunity.
  • Of course some systems may always be fed with the same bag type whilst others may be required to be more flexible regarding bag dimensions depending upon where the raw materials are purchased. Also, some applications need 25kg bags to be fed into the same system.

4. Consider the process requirements

It is important to fully consider the requirements of the process system itself.

Relevant factors include:

  • whether the discharge of bag contents is required by weight or by volume
  • how the material should reach the next part of the process
  • whether a controlled feed rate is required, particularly if the product feed is vertically down into the next part of the process
  • How continuous feeding can be achieved whilst the bag is being changed
  • If there is a requirement to remove the bag when it is partially discharged

5. Understand the material characteristics

The flow properties of the material from the bag can vastly affect the machine specification. Some materials may flow smoothly from the bag with no assistance whilst other materials may compact in the bag during transportation or storage. This could lead to a requirement for discharge aids such as bag massage or vibration.

Dust from very fine material can be managed with dust extraction systems and protection from hazardous material can be provided using ATEX features.

Static grounding and monitoring requirements also need to be taken into consideration.

6. Ensure that design engineers have all the relevant information

System designers must be fully aware of all the layout and process requirements as well as material properties and variabilities to ensure that the project is effectively scoped. Streams with variable material characteristics must have the flexibility to cope.

7. Ensure that the supplier best fulfils the project parameters

If a complete turn-key system is required then a supplier that can offer the complete project management service from initial concept to final commissioning is appropriate. However, if a smaller element of a process system is needed then a partner who will work proactively to provide a right first time solution can be a better match.

For example, Guttridge can offer a wide range of small rigid screw conveyors and hopper/elevators for customers that require transport of material from beneath a bulk bag discharger into the process system.

8. Search for specialist material testing expertise

Good bulk bag system suppliers are increasingly using contemporary, state-of-the-art material testing facilities. Interpretation of this scientific data, combined with technical expertise and experience ensures that right first time solutions will be supplied.

9. When considering price, think about lifetime operating costs

Bulk bag systems have long lifetimes. Therefore costs of operation, maintenance and spares supply should be thoroughly researched. Good suppliers will have the infrastructure in place to offer long term maintenance and support packages.

10. Investigate care packages

Leaders in many bulk materials handling systems are now offering machinery lifetime care packages that include both routine and emergency maintenance. If full support can be provided in-house this may not be required but it can substantially relieve in-house support by leaving it to experts.

Greg Bedford, Guttridge Internal Sales Proposals Engineer has more than 30 years۪ experience of offering standard and bespoke food processing systems solutions. Guttridge can provide a wide range of bulk bag discharge systems with many optional extras and features. Call Greg for free advice on

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About Guttridge

With a foundation of 50 years of experience, Guttridge is a flourishing company, globally respected for delivering well-engineered, reliable materials handling solutions that continue to anticipate dramatically changing industrial needs.