DUAL CORING TOOL Russian patent published in 1998 - IPC

FIELD: bore-hole drilling machinery and equipment. SUBSTANCE: this relates to dual coring tools with split coring pipes. Device has external pipe with drilling bit, hollow adapter in its upper part, internal widening core receiving pipe which is made up of two equal half-pipes with core taker. Core receiving pipe is connected with adapter of unit used for axial displacement of core receiving pipe. Aforesaid unit has shaft and spring enclosed in housing, contracting members and bearing unit. Shaft of axial displacement unit is rigidly connected to combined halves of core receiving pipe. It is divided into two halves along plane of contact. Resilient contracting members are slipped over aforesaid shaft which is spring-loaded with spring resting against shaft end face. EFFECT: higher efficiency. 1 dwg