When a major UK pet food producer wanted better machine utilisation with the aim of raising its OEE (overall equipment effectiveness) by 3 points, it decided to ask experts at bearing specialist NSK if they could evaluate processes and systems to help with this improvement goal.
The prompt to engage NSK arrived after hearing about the company’s AIP Added Value Programme, in particular its ability to improve bearing life through a mixture of training and application engineering services. This approach focuses firmly on identifying improvement opportunities in three keys assets: people, plant and processes.
At the pet food facility, the management team was aware of various application issues which NSK experts viewed, leading to the creation of a process map. The process map is one of the most powerful elements of AIP as it focuses on generating a complete documented review of the production process from start to finish, placing particular emphasis on critical bearing applications. In this case, the process map identified five areas for potential OEE improvement.
Trials subsequently began, initially focusing on the more costly application: the plant’s pellet extruder. Here, the customer was experiencing bearing failures and loss of production every 10-12 weeks on average.
Using analytical data from the trials, NSK determined that the existing grease lubrication was not fulfilling the life expectancy of the bearings. The expert engineers therefore recommended a high-viscosity oil for longer life alongside a suitably durable bearing solution.
The customer duly replaced its existing bearings with high-quality NSK spherical roller bearings from the company’s EA series, as well as NSK spherical thrust roller bearings. EA series bearings, which feature pressed steel cages, offer high load-carrying capacity, high limiting speeds and high functionality under operating conditions involving elevated temperatures, making them ideal for the pellet extruder and other applications at the pet food plant.
After reassembly, the extruder ran for 7 months without any bearing failures, resulting in impressive cost savings of £70,000 thanks to reductions in production downtime and maintenance. In addition, the pet food plant achieved its goal of raising OEE by 3 points.
At the request of the customer, NSK also conducted on-site bearing training for the plant’s maintenance staff, providing even more added value as part of the overall solution.
2) NSK EA series spherical roller bearings offer high load-carrying capacity and high limiting speeds in challenging conditions. Photo: NSK