PTT Exploration & Production plc successfully completed the longest well drilled in Thailand at its Bongkot gas field, with a long hole drilled length of more than 5 km.
Unocal Thailand bored the Funan J-13 gas well at a rate of 5,145 ft/day, believed to be a world record. This performance eclipsed the previous single-well Gulf of Thailand record of 4,720 ft/day set in 1997 on the Satun A-17 well, also by Unocal Thailand.
Funan J-13 was drilled to 9,862 ft (7,900 ft true vertical depth) in 46 hr.
BK-9-L is the longest reach well ever sunk in the kingdom, PTTEP said. It was drilled on a deviated maximum angle of 73° and taps gas and condensate reserves of 20 bcf located almost 4 km horizontal distance from an existing wellhead platform.
These hydrocarbon reserves would otherwise not be able to be produced without installation of another platform, which is not economic. The well will be produced and offers a production life as long as 10 years, said Maroot Mrigadat, PTTEP senior vice-president.
Lying about 600 km south of Bangkok, PTTEP-operated Bongkot field is producing 550 MMcfd of gas.
Unocal Thailand said the penetration rate for the entire Funan J platform development program averaged 4,010 ft/day. This was 21% faster than the previous record of 3,300 ft/day for all wells on the Satun L platform in 1997. The 14 well drilling program at the platform was completed in 61 days.
Tara Tiradnakorn, Unocal Thailand's vice-president for operations, said the company achieved the two drilling records because of its familiarity with the behavior and characteristics of Gulf of Thailand geology and the application of slim-hole drilling.
Slim-hole drilling, pioneered by Unocal in Indonesia, uses a smaller well diameter than conventional oil and gas wells to reduce drilling time and produce fewer well cuttings.
Drilling cost for the 14 wells on the Funan J platform averaged $800,000/ well, or $77.05/ft. The J-13 well cost $636,000, or $64.50/ft. Unocal has drilled more than 1,200 wells in the Gulf of Thailand.
The Funan J platform is expected to produce about 46 bcf equivalent of natural gas. The platform was to have started up in May 1999 at a rate of 60 MMcfd of gas.
Copyright 1999 Oil & Gas Journal. All Rights Reserved.
