ESS Engineering’s air cannons are helping keep bulk material flowing across the country.
Material blockage in bulk storage had been previously under license systems is a common occurrence. Silos, kilns, and bunkers can have so much build-up that it can impede operations or even stop flow altogether.
This material build-up becomes a safety hazard if it requires manual removal. Clearing the blockage from the outside has historically involved hitting the structure with a hammer, causing structural damage and presenting a manual handling risk.
ESS has a comprehensive range of flow-aid devices, from air cannons to industrial vibrators to silo cleaners, all of which can be adapted across many bulk-handling applications.
In the bulk materials and handling sector, air cannons have numerous applications. They can quickly solve bulk flow problems in silos, hoppers, and chutes, and are often applied where vibration is impractical or other methods are too expensive.
ESS air cannons are pneumatic bulk material flow aid systems that utilise the release of a volume of compressed air. This sudden release of energy is directed through a transition pipe into compacted material in a bulk storage structure to fracture blockages, restoring material flow and regaining storage capacity.
When the opportunity came up for ESS to design its own line of air cannons, it chose to focus on designing a more powerful, safer, flexible, and customisable version.
“We had our engineers redesign the valve arrangement and had it independently tested by The University of Newcastle Research Associates against other air cannons on the market,” ESS account development manager, Ken Minch, told ABHR.
The design demonstrated strong performance and quickly gained traction across the bulk handling sector. Since their launch, ESS air cannons have been installed on silos, hoppers, chutes, and storage piles throughout the country, providing rapid, repeatable relief from flow obstructions.
Air cannons, compared with other methods like vibrators, can affect a much larger area inside the vessel. Instead of energising a small zone on the wall, a single blast can sweep across the vessel’s surface and aerate the stagnant material.
Restoring storage capacity and operational efficiency
Material blockages can reduce a storage vessel’s functional capacity by half or more. ESS branch manager Bryce Cook cited a dustbin example in which 150 tonnes of material were hung up inside a 300-tonne bin.
“That was half of the infrastructure’s capacity gone,” he said. “Just two air cannons were able to give them back their silo again.”
This ability to reclaim lost capacity quickly is one of the key advantages of the technology.
Designed for safety and reliability
Compressed air systems inherently pose risks, so ESS engineered its air cannons to minimise exposure to stored energy. The units fill with air immediately before firing, rather than staying continuously charged. Air is released directly through the valve and discharge pipe during activation, reducing the time the vessel remains under pressure.
The mechanical design also supports long asset life. Cook said the cannons have only one moving part the piston responsible for releasing the air charge, the piston that releases the air.
“Occasionally, you may need to replace the O-rings, which is why they are designed to provide quick access to the valves inside,” he said.
Because firing cycles occur roughly once every 15 minutes, component wear is extremely low. ESS also manufactures cast-vessel options with no weld seams, eliminating potential fatigue points. Minch said the cast-vessel option is able to last for around 15 million cycles, and in many cases, far longer.
“I’ve inspected air cannons that I had installed as an apprentice that are still in service today,” he said.
Optimising air cannon performance for every site
ESS works closely with customers to determine ideal placement, firing sequences, and design options based on material characteristics and vessel geometry.
At truck loading stations, the process can be as straightforward as a driver exiting the cab and pressing a button to restore flow.
The company maintains an extensive library of case studies spanning coal, gypsum, crushed rock, woodchips, and numerous other bulk materials.
Minch said decades of experience with air cannon technology have allowed ESS to continuously refine the design.
“They’re extremely effective pieces of equipment, and our clients love them.”