| 摘要 |
FIELD: drilling boreholes for oil-and-gas industry, geological prospecting, etc. SUBSTANCE: lock has nipple and sleeve parts. Their end faces in plane of thrust joint are provided with outside chamfers. Chamfers are used as protector of thrust joint planes from impacts inflicted on side surface of lock. Dimension of chamfer $$$, mm is found from this relation: $$$, where $$$ - minimal recommendable dimension of chamfer, mm: $$$ - maximal recommendable dimension of chamfer, mm. Innovation will prolong service life of lock joint 1.5-2.0 times, reduce loss of washing liquid and cuts power needed for drilling. EFFECT: high overall efficiency. |
