CPC E21B 33/127 (2013.01) [E21B 23/06 (2013.01); E21B 33/12 (2013.01); E21B 47/06 (2013.01); G01L 19/0618 (2013.01)] | 17 Claims |
1. A method for setting an inflatable packer, the method comprising:
positioning an inflatable packer within a borehole;
pumping fluid into an inflatable element of the inflatable packer using a pump, wherein the pump is driven by a motor;
measuring pressure of the inflatable element;
determining a derivative of the measured pressure with respect to time, wherein the pressure of the inflatable element is measured over time, at fixed intervals, and wherein a buffer of L registers of measured pressure is maintained, wherein L is an integral that is equal to or greater than 2, wherein the pressure derivative, D, of the pressure measurements, x, is determined in accordance with the following equation: D=Σi=1i=Lx(i)f(i), and wherein f(i) is the Savitzky-Golay polynomial filter;
determining onset of restraining of the inflatable element has occurred when the derivative is equal to or greater than a derivative threshold; and
upon or after determining the onset of restraining, turning off the motor or slowing down an rpm of the motor.
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