Provided are a directional hydraulic injection tool string and a construction method for a
coal-
bed gas horizontal well. The directional hydraulic injection tool string is characterized by comprisinga guide cone, a screen
pipe, a centering device one-way valve, a hydraulic anchor, a packer, an ejector, a hydraulic eccentric orientator, an upper centering device, a hydraulic releasing and an oil
pipe which are sequentially connected, the hydraulic eccentric orientator is connected with the ejector through a fixed manner, the upper end of the hydraulic eccentric orientator and the lower end ofthe ejector are respectively through the upper centering device and the packer connected with an upper movable bearing and a lower movable bearing, and under the action of hydraulic, the eccentric orientator drives the ejector to achieve the function of directional ejection; the directional hydraulic injection tool string has reasonable design and complete functions, and higher reliability, stability and safety of the combined
system, can achieve the function of outer
pipe anti-channeling and fixed point fracturing, also achieve hydraulic sand blast perforation of large displacement, large hole, and orientation and subsection fracturing operation of large displacement and a large scale, is applied to the construction of
coal-
bed gas
horizontal wells with complex conditions, such as cementing wells, uncementing wells and the like, and the directional hydraulic injection tool string has the advantages of high construction efficiency, low construction cost, a large scale of production increasing and improvement, high success rate of the construction and a good reconstruction effect and the like.