Abstract:
This study aims to reduce the cost of scaffolding installation/uninstallation in a
maintenance section of an electrical power plant. The scaffolding installation/uninstallation is
crucial tasks in the maintenance work. These tasks are difficult and time-consuming process
because the working areas are either closed or quite high. The case study electrical power plant
has revenue around one million baht per an operating hour. As a result, the electrical power plant
had an immense loss opportunity cost due to the time-consuming maintenance work. In addition,
the rent cost of scaffolding using in the maintenance work is quite high. Regarding to these
problems, the principle of Project Management and PERT/CPM have been applied in this study in
order to analyze the problems and to find the critical path. Basic problem-solving tools such as
fish-bone diagram and brain-storming technique have been applied to find the causes of the
problems and to reduce the delay activities in the critical path. Consequently, the project plan was
improved and rescheduled. Moreover, the principle of engineering economy was used to calculate
and to support the decision in either scaffolding investment or renting. In conclusion, this study
can reduce the time of scaffolding installation/uninstallation 12 hours or 6.25% of previous
method. In other words, it can reduce the loss opportunity cost 11,640,000 baht in total excluding
the operating cost. The study shows that the electrical power plant should invest for scaffolding
instead of renting. The investment of 5% MARR will have IRR value at 14.65%, NPV is
62,286,210 baht, IRR is 2.05 and payback period is 6.52 years.