Mandrel assembly for bias sensor

The invention belongs to the technical field of oil and gas drilling, and particularly relates to a mandrel assembly for an eccentric weight sensor. The mandrel assembly for the bias sensor comprises a rotating shaft; and the weighting block is fixedly arranged on the rotating shaft, and enables the gravity center of the mandrel assembly to deviate from the rotating axis of the rotating shaft. The invention provides the mandrel assembly for the eccentric weight sensor for a mechanical directional drilling tool, and the mandrel assembly can be used as a drilling measuring tool and instrument and can also be used as a stable platform of a rotary steerable drilling system, a vertical drilling tool and the like which need to stabilize the gravity center. 本发明属于油气钻井技术领域，具体地，涉及一种用于偏重感应器的芯轴组件。用于偏重感应器的芯轴组件包括：转轴；固定设置在所述转轴上的偏重块，所述偏重块使所述芯轴组件的重心偏离所述转轴的转动轴线。本发明为机械式定向钻井工具提供了一种用于偏重感应器的芯轴组件，芯轴组件除了可用作钻井测量工具及仪器，还可用作旋转导向钻井系统、垂钻工具等需要稳定重心的稳定平台。