Abstract
This research shows results of some tests about a developed skimmer which recovers the spilled oil from water surface by a raking system. It stores and separates water from oil/water mixture in its tank. The separated water is drained out from its tank by a diaphragm pump. The tests were operated in the large wave basin of STORMS with bunker C heavy oil and its emulsion. The grab-buckets have been used often as the oil skimming tool when viscous oil spilled at the coast, and it is appreciated its good recovery rate and poor efficiency. So that our objective of this research is to develop the skimmer for persons who normally construct marine structures by crane and work vessel like the grab-bucket, and to improve its recovery efficiency by separating water in its bucket tank by draining with pump.