RAS^™ Reservoir Analysis Sonde Safety Sub

Applications

• Reservoir monitoring
• Formation evaluation
• Wellbore performance and integrity
• Primary reservoir description where openhole logging is constrained

Features and Benefits

• Ensures safe operation of RAS neutron generator
• Onboard pressure and temperature sensors monitor environment conditions. Switch-on only possible once programmable thresholds are met
• Onboard power switch to disable power in case of tool failure
• Watchdog feature monitors memory tool. Initiates restart after 45 seconds in the event of communication failure or reboot request

Tool Description

The Weatherford RAS reservoir analysis sonde safety sub is a mandatory component in a memory-RAS string.

Positioned between the battery and the memory logging tool (MLT), the RAS safety sub is equipped with pressure and temperature sensors to monitor borehole conditions against user-programmable thresholds. A power switch is included in the RAS safety sub to disable battery power to the MLT (and all attached tools) in case of tool failure. 

In memory-RAS operation, the RAS safety sub serves as a watchdog for the MLT’s health (via handshaking in a designated communication link) and periodically reporting instantaneous pressure and temperature measurements to the MLT. 

In case of a communication failure or MLT requesting a reboot, the RAS safety sub enters a reset cycle that cuts off power to the MLT and RAS, re-enabling the power downstream after 45 seconds. This operation automatically puts the RAS into idle mode and allows the MLT to re-initialize and to recover from a failure.

Specifications

Ratings and Dimensions