The invention relates to a lifting-free borehole bottom
rope freezing
coring drilling tool and method. The lifting-free borehole bottom
rope freezing
coring drilling tool comprises a salvaging device, an inner
pipe assembly and an outer
pipe assembly. According to the
coring method,
liquid nitrogen is fed into a
liquid nitrogen chamber of the salvaging device; the salvaging device is fed into an outer
pipe once the roundtrip is ended; the salvaging device is connected with the inner pipe
assembly so as to feed the
liquid nitrogen into a
freezing chamber; and the liquid
nitrogen absorbs heat and is gasified so as to freeze the
hydrate rock core. By adopting the lifting-free borehole bottom
rope freezing coring drilling tool and method, the liquid
nitrogen can be prevented from being gasified due to heat dissipation and vibration during drilling, so that the freezing efficiency of the liquid
nitrogen can be improved. According to the lifting-free borehole bottom rope freezing coring drilling tool and the coring method, a small
drill bit is arranged on the inner pipe assembly and is driven by a large
drill bit to
drill together, so as to obtain the
rock core with required dimension; a drill column does not needed to be integrally lifted from the borehole, so that the lifting-free continuous drilling and coring can be realized; and the small
drill bit and a clamp spring seat are disassembled during sampling, a half-closing pipe is drawn out of a
rock core pipe together with the rock core, and a rock
core sample is stored in a liquid nitrogen
storage tank or a high-pressure container.