Drilling hub yog ib qho cuab yeej downhole uas xa cov axial cuam tshuam rau qhov cuam tshuam ntawm txoj hlua tho.Jars feem ntau yog thawj kab ntawm kev tiv thaiv cov yeeb nkab daig thiab tuaj yeem cawm cov neeg ua haujlwm los ntawm kev nuv ntses thiab kev kho mob sai sai los ntawm "jarring" txoj hlua dawb.
Landrill tuaj yeem muab Hydraulic Drilling Jar & Ob Chav Acting Hydraulic-Mechanical Drilling Jar & Super Nuv Ntses Rag