Nov 2018, Vertechs RWSS was used to eliminate coal formation instability successfully in southwest of China. This typical low formation pressure well with coal bed and thief zone has encountered severe losses and collapse when drilling through the trouble zone (1076-1634m). After more than 20 unsuccessful attempts of treating losses and wellbore stabilizing with LCM pill and cement slurry, the operator was forced to plug back then sidetrack. Vertechs real-time wellbore strengthening solution was applied to the sidetrack interval. Around 7 ppb ULIA® ultra low invasion additive was added into the mud system while drilling. Vertechs High Pressure Invasion Tester (HPIT®) was also used on-site to provide real-time reference for drilling fluid invasion management and optimization of ULIA® concentration. Dec 2018, The trouble zone was drilled successfully without wellbore instability issues such as collapse or stuck pipe.