The SBM (synthetic based mud) which is used in Japan is the ENVIROMUL system produced by Halliburton, and temperature limitation of this SBM is 160°C. So far, the SBM have been used in the Hokkaido area mainly with below 150°C BHST (bottom hole static temperature).
However, the SBM were applied to 12-1/4″ hole section in Katakai SK-29D/29D-1 that BHST is 160-170°C in 2012 and high-temperature measure of the SBM succeeded.
Also in 2012, the SBM were applied to 12-1/4″ hole section and 8-1/2″ hole section in Katakai SK-30D/30D-1 that BHST is over 180°C. The SBM must be given resistance to the higher temperature.
As a result of having examined high temperature measures, the SBM were used well in Katakai SK-30/30D-1 of JAPEX which recorded 180°C (Results) of maximum BHST.
