Well velocity logging
AssigneeShell Oil Company
InventorsMoye Wicks, III, Boyd B. Moore
Life of this patent
Estimating the term…
Abstract
A device having a large fluid drag tendency is lowered into a well at a rate which gives no net drag against the fluid. The condition of no net drag is indicated by the tension in a line used to lower the tool into the well. When the spool-off rate is such that this tension force is equal to or slightly exceeds the weight of the tool plus the weight of the line in the borehole the tool is moving at a speed equal to the average flow velocity in the well. This velocity may be determined by measurement of the spool-off rate.
Claims13
A method for logging fluid velocities in a portion of a wellbore comprising the steps of:
- providing a high drag member which passes through the portion of the wellbore to be logged with little frictional resistance against the wellbore walls and provides a high drag resistance for fluids passing around the high drag member within the wellbore;
- suspending the high drag member within the wellbore by a line;
- moving the high drag member within the wellbore at a velocity which results in tension on the line at the wellhead which equals or slightly exceeds the weight of the drag member and line in the wellbore;
- and
- determining the velocity of the fluids within the portion of the wellbore by measuring the rate at which the line is being taken up or fed out when the tension on the line slightly exceeds the weight of the drag member and line in the wellbore.
A well logging apparatus capable of measuring fluid velocities within a wellbore comprising:
- a) a high drag member which passes through the wellbore to be logged with little frictional resistance against the wellbore walls and provides a high drag resistance for fluids passing around the high drag member within the wellbore;
- b) a line capable of suspending the high drag member within the wellbore;
- c) a means to maintain a tension on the line at the wellhead which slightly exceeds the weight of the high drag member and line in the borehole;
- d) a means for lowering and raising the high drag member within the wellbore at varying rates;
- and
- e) a means for measuring the speed at which the line is going into the wellbore or being pulled out of the wellbore.
Dependencies are inferred from the claim text.