APS’s next-generation SureShot™ MWD natural gamma sensor employs a rugged scintillation counter and photomultiplier mounted in a specially designed package which provides protection against the high levels of shock and vibration encountered in the drilling environment. In addition, this extensively qualified new design offers environmental monitoring capability and lower power consumption, while maintaining back-compatibility with APS’s earlier sensor designs.
The easy-to-use SureShot surface system scales natural gamma ray data to API units; corrects for borehole size, mud weight and drill collar effects; assigns each point a depth from the depth tracking system; and plots both real-time displays and configurable hard copy logs. Data can be exported in standard industry formats (WITS and LAS).
The gamma sensor’s built-in accelerometers measure axial and lateral vibration. Peak axial shock, lateral shock, and temperature data are stored in on-board memory every 5 minutes, up to 5,000 hours. Information on the service history of the tool is also stored in on-board memory.
This lifetime log provides valuable information to evaluate the health of the tool, and to develop preventative maintenance cycles base on the actual operating environment over time rather than total downhole hours alone. Vibration measurements can also be used to justify claims for repairs that are a result of out-of-spec drilling conditions.
The MWD Gamma sensor sends a combination of gamma ray and tool face data transmissions allowing logging while steering and sliding.