Synthomer is a world-class supplier of synthetic polymers to many different industries, ranging from paints and adhesives, to textiles, speciality papers and plastics. Ian Cumming, a Reliability Engineer at the site in Grimsby, kindly wrote the following piece, which highlights a recent success that they had using the Ultraprobe 10000.

"During a weekly routine inspection carried out by our Reliability Technician, it was identified that the drive motor on one of our cooling tower water pumps was found to be running hotter than normal, and the pump's bearings were also particularly noisy. This prompted the technician to carry out a further investigation."

"On closer inspection using our FLIR thermal imaging camera, it was found that the pump drive motor had risen in operating temperature, mainly on the drive end bearing. A temperature of 63°C was recorded, which was 10°C higher than the previous reading taken, and a 'hot spot' was clearly visible on the motor casing."

"The pump was also creating an excessive amount of noise above and below the 20 kHz range, and a reading of 72 dB was recorded using our Ultraprobe 10000. We determined that the pump drive bearing was the cause of this noise."

"The pump coupling guard was removed and the tyre coupling was disconnected. The coupling was found to be out of alignment, which had put extra load on the motor and pump bearings, and had caused the tyre to show signs of imminent failure."

"The pump casing was then split. Although no debris was found inside the pump casing, and the pump wear rings and impellor were still in good condition, the pump rotor was extremely stiff to rotate. The opportunity was then taken to remove the pump rotor, which showed that the pump non drive end bearing was free, but that the drive end bearing was stiff to rotate. The pump was consequently removed and dispatched for further inspection and overhaul."

"When the pump rotor was later disassembled, the drive end bearing was found to be extremely worn (see picture). There were two causes for this."

"Firstly, although the bearing had some grease, it had broken down and degraded. The lubrication pathway in the bearing house was blocked, preventing the grease from the auto-lube to penetrate the bearing. This was also indicated when the auto-lube was removed, as the grease had pressurised and was expelled from the grease line, indicating a build-up of back pressure. The bearing had also become loose on the pump shaft, causing it to move and damage the bearing mounting surface."

"Secondly, the misalignment between the pump and motor shafts had also put extra strain on the drive assembly, and would have contributed to the bearing failure."

"In summary, as the pump rotor was extremely stiff to rotate, this would have put extra strain on the drive motor, which caused the rise in operating temperature. It was our recommendation that the motor bearings were changed at this time due to the temperature rise in the drive end bearing, which would help prevent future failure due to possible damage caused to the bearings that have been operating under excessive load and temperature."