Whenever a turnaround schedule is accelerated (shortened) or extended (lengthened), the initial cost estimate will be affected.

Schedule Acceleration (Shortening)

Sometimes it is desirable or mandatory to shorten the turnaround. This may involve overtime or increased staffing levels.

The acceleration can be accomplished by scheduling weekend work, if the original schedule was predicated on a five or six day work week. If the original schedule was set up on a seven day week, then additional manpower or selective overtime (on critical and near-critical work) should be contemplated, if possible (as when working ten hour shifts; then you could place all crafts on twelve hour shifts to expedite all critical and near-critical work).

The overtime pay costs should be balanced against the decrease (if any) in overhead, supervision and rental costs achieved by a shortened schedule.

The following formula expresses these concepts:

Total Turnaround Costs = (labor cost + overtime cost) - ((overhead + supervision + rental) * days acceleration)

Where "days accelerated" are mechanical work days, and not calendar days (except possibly some rentals).

Schedule Extension

Sometimes a lack of urgency due to feed stock, inventories, sales or economics may dictate a longer shutdown (outage) in order to save on overtime costs, utilizing plant personnel with a minimum involvement with contractors, etc.

The schedule extension can be accomplished by eliminating weekend work (using a five-day work week) and eliminating overtime work.

The savings should be balanced against a potential increase in overhead, supervision and rental costs caused by the extended schedule.

We can use this formula:

Total Turnaround Costs = (labor cost + overtime cost) - ((overhead + supervision + rental) * days extended)

Again, "days extended" are mechanical days (work days) and not calendar days (except possibly some rentals).

Note that there are certain problems associated with extending the schedule:

• There is no overtime incentive and workers may deliberately slow down the work to force some overtime work
• With no overtime incentive it may be very difficult to hire competent contract labor

Effect on Manpower and Morale

Changing the schedule once the turnaround has started is not advisable, due to these considerations:

• It may be difficult or impossible to attract quality workmen after the turnaround is already in progress.
• Available labor pools may be depleted due to other turnaround work in the vicinity.
• Workers may quit if their overtime pay incentive is removed, or if their work week/shift is altered.
• Worker morale may suffer from shifting schedule priorities, reassignments and major changes in staffing.
• Supervision may not be adequate to handle a faster, more compressed schedule.
• Manpower density in the available work space may reach saturation levels, with its attendant decrease in productivity.
• Increasing manpower staffing levels may require increasing the level of support, which means more supervision, tools, equipment (rentals), etc.
• Extending the schedule removes the sense of urgency, and the level of interest and dedication decreases accordingly. This requires a greater effort to schedule and to track progress to prevent overshooting the completion date resulting from a laid-back attitude towards the turnaround.