• We mentioned in last week’s post that we can detect pump failure from EDR data (1Hz to 0.2Hz). We also mentioned that washout and pump failure signatures are so similar that often there is not sufficient basis to differentiate between them.

    In effect, washout and pump failure signatures are the same except for the flow out hydraulic coefficient. During a washout, flow out hyd. coefficient decreases while during a pump failure flow out hyd. coefficient remains constant. Now, we know a flow paddle is not the most sophisticated sensor in the world. If flow out is unavailable or not calibrated properly, distinguishing between the two dysfunctions become even more impractical.

    For this reason, the sum of washout and pump failure beliefs is recommended to be monitored instead of each one individually. If the sum of these beliefs reaches the event threshold, a washout/pump failure event is established. From that point on, the operator can verify which of the two dysfunctions is truly occurring. Check out last week’s post for details on washout detection. If you have questions, feel free to put them in the comments section, or email us at

    At this stage, you may have noticed that the unplanned event node in the network has “Packoff” in it. We will delay discussing that for now, though a lot of you may already know the signatures that belief looks for. Next week, we will start discussing drilling dysfunction models. Stick slip, whirl, bit bounce, bit balling, etc. Stay tuned to this channel.

    Please click below for additional slides on this topic:

    Pump Failure Detection