SKF has introduced a new quarry kit that incorporates sealed spherical bearings.
The result is a a three-barrier solution that cuts maintenance time and extends the lifespan of the bearing.
“The real bonus here is the guys can fit the bearing … on the job, on the conveyor, in the middle of the night, surrounded by dust and dirt and everything else. But because the bearing is sealed, none of that contamination gets into the bearing,” said Leach.
“They can complete the job, put it back together again, run it, knowing that the bearing has nothing but quality lubricant inside and is fully sealed.”
Likewise, the process to fit-seal bearings is simpler overall.
“Previously, teams have been taught to use feeler gauges to measure bearing clearances. Because the bearing has seals on it, SKF had to develop a new technique for fitting these bearings. So, it got away with all the loose bits and pieces on the job,” Leach said.
Making the fitting process easier is particularly beneficial for quarries that hire contractors.
“What a lot of quarries now have is contractors on-site – they don’t have their own people … they hire guys as required for labour jobs or if breakdown happens,” Leach said. “They come in, they do the job, they leave. This process is simpler for them to do as well.
“There’s basic paper instructions, there’s online instructions and there are YouTube video instructions.
“The fitters can get up there with their phone, watch the video and once they’ve watched the video they go, ‘I know what to do now’ and then they go and do it.
“The access to that information they need to do the job correctly is actually increased as well.”
The sealed bearing is what makes up the first barrier in SKF’s three-barrier solution.
A sealed spherical roller is “coupled up with the three-barrier solution”, SKF Group business development manager Graham Thomas explained.
“You’ve got a housing seal, you’ve got a grease barrier, so we fill the housings up by around about 70–80 per cent grease and then you’ve got your seal on your bearing,” he said.
Leach elaborated on this.
“Working inside out is the bearing. So upon assembly that bearing is protected while the guys are doing the fitting job,” he said.
“Then they fill the housing up with grease, which becomes the second barrier. And then they fit the split rubber seals to the housing or seal and end-cover, depending on the application.
“And once that’s brought together, that becomes the third barrier.”
All three barriers work to keep contamination out, lowering the likelihood of problems.
“Contamination has to get through the external seal, past the grease that’s been used as a seal, past the bearing seal,” Leach said.
“So basically, you have to wear through your seals, all the grease has to disappear, your bearing has to basically fail before there’s any problems along those lines.”
The increased longevity of the bearings will benefit quarries in a number of ways.
For example, removing the need to purge excess grease usage saves time and money, and contributes in reducing the environmental impact. The bearing also no longer requires a constant flow of grease through the housing.
“So they can cut their lubrication racks down by 90 per cent. In some cases, some of the smaller ones, probably 100 per cent of what they’d normally put in there,” Leach said.
Removing the need to change the lubricators also decreases the chance of injury.
“There are barriers around any area where the people can get in and get hurt ,” Leach said. “So to get in to lubricate, they either had to run lubrication lines out, or they had to enter that area to change the automatic lubricators.
“By not having to do any of those processes the staff themselves are safer.”
“This solution can also be applied to larger shaft sizes. Some problems may require a different approach but, with the support of SKF I’m sure we will have a solution to match the problem.”
Visit skf.com/au for more information.
This feature first appeared in the June issue of Quarry.