Abstract:
The object of this work was to possibility study of changing three water pump
shaft seals from the existing gland packing seals to mechanical seals of a Hydrocarbon
Resin Plant. According to past data analysis, the water pumps often broke down
causing profit loss from output reduction of around $0.42 million per year. Also, leaking
of seal cooling water was about $.018 million per year. The root cause of the Joss was
because of the friction between the gland packing seals and shaft sleeve. This friction
caused high temperature of up to 80-90°C. In this situation, the pump motor could take
more current until the breaker was cut off. After that the seal was adjusted. Because of
the mentioned problem, the mechanical seals were used to replace the existing ones of
the three water pumps. This changing could reduce time lost because of the seals. Six
months after the changing, the three water pumps have not been broken because of the
seals. With the new mechanical seals, the motors have taken less current. The plant
could save of around $.022 million per year. The investment of the changing was about
$.019 million for the three mechanical seals. After economical analyzing, the pay back
period was about 5.5 months. The values of IRR and MARR were 5.5% and 5.0%,
respectively. If all of 20 water pumps using the mechanical seals, the saving for this
plant could be $ 4.0 million per year.