Development of Risk Assessment System for Coal-Bed Methane Underbalanced Drilling

As there are a lot of factors with complexity and uncertainty, the process of coal-bed methane under balanced drilling has great risk. In order to overcome the one-sidedness and limitation caused by single evaluation method, the combined evaluation model for coal-bed methane under balanced drilling is established based on the combined evaluation theory. And on the basis of the software platform of Visual Basic 2005, the risk assessment system for coal-bed methane under balanced drilling is developed. By practical application and test, it is proved that the system has certain engineering value.