Fix it: Emergency repairs that can keep the combine moving
Published 24/08/2016 | 02:30
You know the deal, it's 3pm on a Friday evening and Murphy's Law is about to strike again. A contractor calls up in a panic, having just realised that he's got badly damaged helical flights on the unloading auger that lifts the grain from the bottom of the grain tank.
A replacement auger cannot be sourced for a number of days, especially on a Friday evening, and running the damaged auger is burning drive belts off like a hot knife through butter. The only option to keep the combine operational for the weekend is to repair the existing auger.
The contractor wasn't sure how the auger got damaged in the first place, but as you can see from the picture, the last 300mm of flights were basically rendered useless. This means the auger is moving grain towards the exit point of the tank all the time, but the auger is unable to clear itself at the exit point, leading to a build-up of grain and pressure that in turn snaps the drive belt.
To begin the repair job, the damaged flights were cut away and then I fabricated replacement sections from sheet steel.
Ideally, pre-fabricated replacement helical sections would be purchased and welded into position, but waiting until after the weekend to source the parts was not an option in this instance!
So, an undamaged section of the helix was cut out and flattened to its original profile. This created a template which was used to cut out the replacements.
The replacement sections were then tacked into position, and worked around the shaft to create the progressive helix. It was important to replicate the original as closely as possible in order to keep a smooth flow of grain.
The steel needs to be the same thickness, supporting gussets should be the same size and welds should be exactly the same length. Ensuring everything stays similar to the original helps reduce the risk of throwing the auger out of balance.
The result? Thankfully, the contractor re-fittted the auger and was able to keep on combining into the weekend with minimal downtime.