Motor tracking and trending drives down costs
June 1st 2007

Suncoast Electric Motor Service, in Tampa, Florida, offers Predictive Maintenance Programs to both industrial and marine customers.

Tracking and trending customer's motors allows early detection of potential problems and enables adjustments or repairs to be made before more severe problems arise.

One of its customers, the Hillsborough County Water Department's Waste Water Treatment division has seven major facilities and over 600 remote pumping sites.Working with the Baker Explorer, Suncoast technicians found multiple applications that offered cost savings. During routine testing, Suncoast located situations where motors were over-sized, undersized,operating with tremendous harmonic distortion, erratic torques and unhealthy loads.

At one large facility, technicians tested six continuous duty Internal Recycle Pumps which are difficult to repair. Prior to February 2002, these were being pulled for routine cleaning on a quarterly basis regardless of operating conditions.

Many failed after less than a year and the rate of failure increased once a motor was rewound and returned to service.

The Internal Recycle Pumps were engineered for 'clean'water. Once properly cleaned,they would operate at about 90% load. Inspection found their tanks had large amounts of semi-solid materials that routinely clogged the pumps no matter how much screening and protection was provided. Consequently,the motors became overloaded quickly and If your decanter centrifuge breaks down or needs servicing, you need it back in service fast. Centriquip provides a comprehensive maintenance and repair service for all decanters, whatever the make.

Neil Lacey is in charge of after sales service for Centriquip. "It doesn't matter what make of equipment you are running – Centriquip, Flottweg, Alfa Laval, Westfalia, Hiller,Guinard, etc. – we can service it, repair it and provide a 24-hour breakdown service,"he said. "Being UK based,we are often we are less expensive than the original equipment manufacturer and can have you up and running much faster." Centriquip can handle any type of centrifuge repair: scroll repairs such as tip rebuild, re-flighting or re-tiling; gearbox repairs; hydraulic rotodiff repairs and re-balancing.

The company also provides a 'onsite' maintenance service using the latest monitoring equipment for vibration and bearing temperature to prevent unscheduled maintenance, avoid unnecessary work and predict when servicing will be required.

often would reach 125% load within a week. More stringent and more frequent cleaning was initiated.

The 'Load History'charge obtained with the Explorer, details tests performed on one pump during a four week period. Tests 1 to 5 found the pump load operating at 120%.

Immediately after these tests were recorded, the pump was stopped, removed, inspected, cleaned and replaced into service. Test results 6 through 10 were recorded immediately following the restart and showed the motor operating at just over 90% load.Tests 11 to 15 were taken one week later and indicated that the load had risen to over 105%. The pump was cleaned and tests 16 to 25 showed the motor will operate at near 90% load when properly cleaned. Tests 26 to 30 two weeks later showed that the motor was not cleaned the previous week as scheduled.

The Explorer has captured important data for the company and demonstrates the importance of monitoring the maintenance schedule for all motors.Operating costs have been cut, there are fewer unplanned outages and less need to replace failed motors.

Energy savings An average loss of 7hp between average load demands of clean pumps compared to the average load demand of pumps when not cleaned is calculated. At 746w/hp, there is 5222w of lost energy every hour. Multiply that by 8760h/year yields 45 744 kWh/year. At .07 per kWh average annual loss per motor is $3202 or $19 212 for six motors.

Pumps are still being successfully trended. Failure rates have dropped, operating costs reduced and the cost of two mechanics spending 2h/week cleaning the pumps easily offsets the cost of repairing or replacing even one pump.

Whitelegg Machines are the UK technical sales and service representitives for Baker Instruments

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