METHOD AND DEVICE FOR WELL DRILLING AND ANCHOR SUPPORT FASTENING IN BOREHOLE Russian patent published in 2006 - IPC E21B7/20 

FIELD: drilling, particularly percussion or percussive-rotary drilling of wells in rock and anchor support fastening in well.

SUBSTANCE: method involves drilling well with the use of crown bit connected to drilling rod; simultaneously arranging casing pipe in well, wherein the casing pipe has longitudinal cut and is spaced from drilling rods; arranging casing pipe in position, in which casing pipe at least partly abuts borehole wall during well drilling. Casing pipe is produced of prestressed material. During well drilling the casing pipe is lowered in well with the aid of tensile load through crown bit connector and/or by impact load application. After borehole forming casing pipe is fixed in well to use thereof as anchor support. Device comprises crown bit connected to drilling rig through drilling rods and casing pipe spaced from drilling rods and abutting crown bit. Casing pipe is formed of prestressed material, for instance of metal and has longitudinal cut. Casing pipe may be connected with crown bit by means of pulling fastener or may cooperate with reducing joint or drilling rig by means of anchor head. Casing pipe may be secured in well by means of anchor fastening.

EFFECT: increased protection against ground caving and anchoring to inner borehole wall directly after borehole wall forming.

15 cl, 10 dwg