Harvester fires - a research update

Author: Ben White, Kondinin Group | Date: 05 Mar 2015

Take home message

South Australian operators experience in 2013 and 2014 shows harvester fires may be reduced with improved harvester hygiene, maintenance and exhaust system shielding treatments, particularly in volatile crops.

Further research is required to further quantify crop ignition temperatures and the areas of harvesters that exceeding these temperatures and therefore require safeguarding.

The best method of fire prevention for harvesters has been harvester hygiene, regular maintenance and vigilance.

A back-pocket-guide produced for GRDC by Ben White and Dr Graeme Quick serves as a summary of fire prevention and minimisation methods for Australian operators.

http://www.grdc.com.au/GRDC-BPG-ReducingHarvesterFireRisk

Research by Dr Graeme Quick on behalf of Grain Producers South Australia (GPSA) indicated ignition temperatures of some crop dusts could be as low as 130˚C but this was only for a handful of crops in one season.

Dr Quick also concluded “The primary cause of harvester fires is found in the engine bay and specifically on the exhaust system.”

Following the lead of the mining industry, a handful of harvester operators in South Australia have trialled exhaust system shielding treatments and have anecdotally reported fewer harvester fires while harvesting pulse and oilseed crops.

 

Figure 1. Left and centre: Examples of muffler and exhaust system insulation in South Australia in 2014. Right: Thermal blankets as used in marine and mining equipment applications.             

Figure 1. Left and centre: Examples of muffler and exhaust system insulation in South Australia in 2014. Right: Thermal blankets as used in marine and mining equipment applications.

These operators have used an alumina-silica compound in cement form has been applied to the exhaust stream including the exhaust manifold, turbocharger and exhaust stream including the muffler. This product has also been used in combination with exhaust blankets and in some cases commercial prototype exhaust plumbing modifications.

Application of the cement is laborious and requires preparation and skill to minimise cracking in-situ due to linear shrinkage and formed stress concentrations. According to operators, drying requires around 1-week in warm dry weather.

Cracks in the cement in operation can see dust ingress and accumulation around the exhaust posing fire risk.

Outside the work of Dr Quick, little research has been conducted to quantify the range of ignition temperatures of various crops across a range of conditions.  Similarly, there is little research documenting which harvester components exceed these ignition temperatures.

Additional research in these areas will assist in determination of ignition points and the prevention of fires through the identification and guarding of areas on various models of harvester that may exceed these temperatures.

Acknowledgements

Dr Graeme Quick

Contact details

Ben White
Kondinin Group
Perth WA 6000
Ph: 0407 941 923
Email: ben@kondinin.com.au