Coalbed methane horizontal well screen pipe suspension well completion method

A coalbed methane horizontal well screen pipe suspension well completion method is applied to coalbed methane exploitation, and is characterized by comprising the following steps: a coalbed methane straight well is drilled, an outer layer sleeve pipe is placed in the well, and well cementing is completed; a cave with 500 to 700 mm diameter is formed at a coal bed section through a mechanical cave forming tool, a multi-branch pinnate horizontal well is drilled, and the horizontal section of the well is communicated with the cave; an inner layer pipe column is placed in the outer layer sleeve pipe; a hydraulic liner hanger is placed inside the upper part of the cave in a position 40 to 60 m below the top of the cave; the bottom of the hydraulic liner hanger is sealed on the inner wall of the outer layer sleeve pipe; four to six inner layer sleeve pipes are connected with the lower end of the hydraulic liner hanger; the lower ends of the inner layer sleeve pipes are connected with a screen pipe; the screen pipe is arranged at the cave; the length of the screen pipe is larger than the height of the cave; and the lower end of the screen pipe is connected with a casing shoe. The method has the effects that coal sheets with big particle sizes are prevented from falling into and blocking the well casing, the unobstructed well casing is guaranteed certainly, and the sand bailing operation as well as the lifting and the descending of a gas production pipe column are performed smoothly.