A raw mill at a major cement manufacturer’s UK site has maintained vital production throughput, thanks to the swift response of a diagnostic monitoring and back-up service from Siemens Mechanical Drives.
The company had a programme of pro-active maintenance in place, and had opted for a condition monitoring service from Siemens about 12 months earlier, for the plant critical drive unit running the raw mill. This particular unit was a Siemens Combiflex DMGH, measuring around 2.5 metres tall by approximately one metre wide. At the heart of the unit was a Flender girth gear, and the monitoring service Siemens operated ensured regular checks were made on bearings, vibration analysis and wear characteristics.
Siemens service engineer Steve Stratton identified the early stages of potential bearing failure during one of these routine checks, and plans were quickly put in place for a scheduled shutdown.
So important was this gear unit to the smooth operation of the raw mill, which produces a significant amount of the UK’s cement requirements, that the cement producer kept a complete spare gear unit on site. During the planned shutdown this was quickly installed and the other gear unit returned to Siemens Mechanical Drives at Leeds for checks.
Sure enough, the early stages of bearing failure were found, so the original unit was serviced and given a bearing and seal change before being swiftly returned to site on standby as a spare.
The costs of servicing the unit were about £40,000, but because the changeover was forward planned, it caused minimal disruption or plant downtime. Had condition monitoring not been in place and the bearing failed, the resulting damage and costs in lost production to the company would have been huge.
As Siemens service manager Gary Husband confirmed, an increasing number of companies are choosing condition monitoring, especially where plant critical units operate: "Without monitoring wear on units that are often operating 24 hours a day, breakdowns can and do occur. The resulting lost production and associated costs can be significant. Predictive maintenance is certainly the key to successful plant operation in conditions like these."