Powergen's Ferrybridge 'C' Power Station near Pontefract, Yorkshire generates a massive 2,000 Megawatts of power at full capacity from four complete boiler and turbine units (500 Megawatts per unit).

The boilers are up to 200 ft high and contain many miles of tubing. If a boiler is not working then its associated turbine is also shut down and no electricity is generated so repairs and maintenance have to be planned meticulously to minimise disruption and loss of revenue. Essential cooling, safety requirements, specialised and skilled tasks and recommissioning - all have to be taken into consideration in proper sequence and in predetermined time scales. Such work is extremely complex and needs to be project managed. At Ferrybridge 'C', PLANTRAC is being used for this purpose by the planners.

In the first instance, what are classified as offload defects, those that cannot be rectified while the machine is running, are listed and logged on PLANTRAC and brought forward for "outages" (offload work periods when the plant is shut down. These may last from 24 to 72 hours).

There are different work groups resposible for boiler, turbine and other maintenance plant areas. PLANTRAC is used to plan and co-ordinate their work. PLANTRAC provides the Ferrybridge 'C' planners with a logical critical path network and bar charts for planning and control.

"For every outage, we can quickly produce bar charts after the unit has come offload showing the work we will undertake and an accurate estimate of the time to completion," explained Rodger Wynn,

Senior Engineer Planning. "Under the new privatised system, we have to return units by a specific time. If we're late, we are penalised and lose money therefore we must be able to predict accurately when we can return the unit back into service.

"PLANTRAC's bar charts are very easy to comprehend. Everybody - management, staff and and contractors - can relate to them and understand our aims."

After a unit is shut down, there first has to be a period of cooling before work can commence. Additionally, there is a very strict safety code requiring the issue of documentation detailing safety procedures for internal operators and external contractors.

Ferrybridge 'C' Power Station

The work on the unit has to be planned and spread over timescales taking into account early and late schedules. PLANTRAC handles this requirement easily and critical activities to the completion of the work can be highlighted as different coloured/types of bars depending on whether the tasks are to be carried out by internal staff or outside contractors.

Rodger Wynn's team has adapted the PLANTRAC package so that it produces bar charts for 3,4 or 6 days with plooter files over-riding them to split each day into 4, 8 and 12 hour segments so that the charts become even more clearly defined.

In compliance with statutory requirements, each of the four boiler/turbine units must come out of service for a major overhaul once every four years. Again PLANTRAC provides the initial planning and framework of the multitude of tasks to be carried out over the 11 to 12 week period by internal teams and up to 400 outside contractors.

PLANTRAC reports several levels of activities starting with the overall plan for management, down through various levels of planning, firstly for each subunit (the boiler for instance) and then down to more detailed reporting for subunits. Contractors may have their own planning systems and they contribute data either manually or by disc into PLANTRAC.

The system is also used to plan the recommissioning of the unit following the completion of work. The unit must be fully tested to ensure that its component parts are operating smoothly and safely before it is put back into service. This recommissioning operation is itself complex and starts on about week 8 of the outage on auxilliary equipment and continues up to the final synchronisation of the unit onto the system (the completion of the overhaul).

"PLANTRAC is well established here at Ferrybridge 'C'. When anything goes wrong, people say, 'Where's the bar chart and what are we going to do?' The 'what if scenarios we are able to project, using the system, help us to determine the consequences of variables such as time and labour and other resources." said Rodger Wynn.

"Computerline in Surrey are always on hand to offer swift and friendly advice - so much easier than dealing with developers who are many thousands of miles away", he added. "The power of PLANTRAC helps us to keep generating the Nation's power."