Optimized design and tests were made on bit matrix formula,diamond parameters and bit nozzle to overcome slow drilling footage and short service life of the wire-line coring bit in hard and compact rock formation,the newly developed bit(S77),with good adaptability,overcame the drilling "sliding" in extra-hard to hard and mid to weak-abrasive rock formations.

Based on the characteristics of the strata in the Qitao coal district and the performance requirement of the drilling fluid for the S_(75) wire-line coring drilling,it selects for some(reasonable) patterns and a compounding ratio of the drilling fluids.

Transient liquid phase bonding for wireline core drill rod;

Working principle and structural features of SYZX75 wire-line coring hydro-hammer are presented.

7 mm wire-line coring tool driven by a mud motor.

To meet the demand of wire-line coring drilling in complicated formation,compound solid-free drilling fluid of CL plant glue was compounded and used instead of drilling mud with the property of wall protection and leaking stoppage.

The application instance of wireline coring technique was introduced with the project case of coal-bed methane parameter well in Baotian-Qingshan area of Guizhou,the drilling techniques were brought forward in accordance with complex formation,unstable borehole wall,being hard to core in coal powder.

The wireline coring technique is an advanced, multi-functional drilling method.

It combines the RC drilling with the diamond wireline coring drilling and uses the same drilling pipes and tools to realize several drilling methods adapted to its formations according to the engineering environments and geological requirements and so on.