The invention relates to an
impact-rotary-type hole-bottom freezing wire-line
coring drilling tool and method for
natural gas hydrate, and belongs to the technical field of geological core drilling. The
coring drilling tool is composed of an inner
pipe assembly and an outer
pipe assembly, the inner
pipe assembly comprises a salvage mechanism, an elastic clip positioning mechanism, a suspension mechanism, a single-action mechanism, a buffer mechanism, an
impact mechanism and a hole-bottom freezing mechanism. According to the
coring method, a
natural gas hydrate core is frozen by adopting a refrigerating unit to circle a
refrigerant, rapid freezing can be achieved, the freezing effect is good, compared with a traditional
refrigeration mechanism, recycling of the
refrigerant is uniform in
refrigeration, and the cost and auxiliary
operation time caused by the supplementary of the
refrigerant can be reduced effectively; and the inner pipe assembly does not rotate in the drilling progress, so that damage of the
mechanical force caused by the rotation of the drilling tool to the
natural gas hydrate core is avoided, moreover, due to the advanced drilling of an inner pipe, the
erosion of the natural gas hydrate core by flushing fluid is avoided effectively, and the core
recovery rate, integrity and representativeness of the natural gas hydrate core are improved more effectively.