Patent ID: 11920454
Assignee: SCHLUMBERGER TECHNOLOGY CORPORATION
Field: Civil engineering (Other fields)
Classification: CPC E | IPC E

Claim 3:
4. A method for predicting a stick-slip event, the method comprising:
training a stick-slip prediction model, wherein the training comprises:
measuring one or more first surface properties;
measuring one or more first downhole properties;
detecting a plurality of stick-slip events;
determining the one or more first surface properties and the one or more first downhole properties that occur before each of the detected plurality of stick-slip events;
determining a distribution in the one or more first surface properties and the one or more first downhole properties that occurs before two or more of the detected plurality of stick-slip events;
determining based on the detected plurality of stick-slip events a frequency that the distribution occurs before the detected plurality of stick-slip events;
assigning each of the detected plurality of stick-slip events to a first stick-slip severity level or a second stick-slip severity level in the trained stick-slip prediction model, wherein the first stick-slip severity level and the second stick-slip severity level each comprise a range from a lower stick-skip amount to an upper stick-slip amount, and wherein the range of the second stick-slip severity level is greater than the range of the first level;

using the trained stick-slip prediction model to predict a stick-slip event, wherein using the trained stick-slip prediction model comprises:
measuring one or more second surface properties using one or more sensors at the surface of a wellbore;
measuring one or more second downhole properties using one or more downhole tools in the wellbore;
inputting measurements of the one or more surface properties and measurements of the one or more downhole properties to a computing system running the trained stick-slip prediction model;
determining, by the trained stick-slip prediction model, that the one or more second surface properties and the one or more second downhole properties match the distribution;
determining a likelihood that the stick-slip event will occur based on the distribution; and
determining a likelihood that the stick-slip event is assigned to the first stick-slip severity level or the second stick-slip severity level based on the predetermined distribution; and

varying at least one of: a rate of rotation of a portion of a tubular string in the wellbore, a weight on a drill bit in the wellbore, a trajectory of a downhole tool in the wellbore or a force exerted on the downhole tool in response to the likelihood that the stick-slip event will occur exceeding a first predetermined threshold and in response to the likelihood that the stick-slip event is assigned to the second stick-slip severity level exceeding a second predetermined threshold.