Brammer offers fan solution to cement plant
An inherent design fault on the bearing assembly of a large centrifugal fan that could have potentially caused a cement plant to reduce, or even stop production due to a failure to comply with dangerous emission regulations has been resolved with the help of Brammer. The UK’s leading supplier of maintenance, repair and overhaul (MRO) products and services provided engineering input, advice and a product application solution to allow operations to continue uninterrupted.
The unreliability of the fan on a wet gas scrubber was preventing Hanson Cement’s plant in Clitheroe, Lancashire, from burning alternative fuels due to downtime on the gas cleaning system, forcing the plant to resort to more expensive fossil fuels. It was discovered that material build-up on the impeller caused increase vibration, which was damaging the non-drive end bearing and its housing, potentially resulting in its failure.
Wendy Taylor, Regional Key Account Executive for Brammer UK, visited the site in Clitheroe with representatives from SKF, the knowledge engineering company, to diagnose the problem. The solution was to replace the non-drive end bearing with an SKF CARB toroidal roller bearing, as well as introducing a regular cleaning routine. No bearings or housings have needed to be replaced since the change, with an estimated cost saving of £15,000.
David Holgate, Engineering Manager at Hanson Cement, commented: “The design of the fan assembly meant the bearing was allowed to float within its housing. In theory, this design has an internal clearance between the outer diameter of the bearing and the bore of the housing for expansion. But due to the imbalance of the fan impeller whilst in operation, the resulting vibration caused wear in the internal bore of the housing.
“Brammer’s solution was to install a fixed housing with a tight fit, with expansion taken care of through the internal design of the bearing itself. Previously we were cleaning the fan impeller on a weekly basis and changing the bearings around every six months. Since the retrofit, we have not had to replace the bearings. We’re very pleased with the help that Brammer provided; it’s been a complete success.”
Wendy Taylor added: “The fact that the faulty scrubber fan could potentially force the cement plant to close because of emission regulations was a serious cause for concern for Hanson Cement. Through our partnership with SKF we have been able to propose a cost-effective, long-term solution which has removed this concern and helped maximise production uptime.”
