Discussion on Key Technologies of Ushaped Connected Wells Construction for Coalbed Methane

Abstract:

Coalbed methane surface drainage wells has undergone through the stages of conventional vertical wells, directional wells, Ushaped wells and pinnate branch wells, the Ushaped well has gradually become the new favorite method of CBM surface drainage with the advantages of synchronous production, less land occupation and maximizing coal seam fractures connection. Taking YQ01 well group as an example, this paper sorts out the problems in the construction of Ushaped butted wells and puts forward the attentions and technical measures in main construction stages to solve the difficulties in well trajectory control, high occurrence of complicated situation and high accuracy of horizontal and vertical wells connection with drilling cost saving, which provides technical reference for the subsequent construction of Ushaped butted wells of CBM.