Calculating pull for a stuck drill string
The disclosure presents processes and methods for determining an overpull force for a stuck drill string in a borehole system. The fluid composition of a mud in the borehole at a specified depth can be broken down into a percentage of liquid and percentage of solids, as well as adjusting for material sag and settling factors. The fluid composition can be utilized to identify friction factors and drag in respective fluid composition zones. Each friction factor and drag can be summed to determine a total fluid drag on the drill string. In some aspects, the total fluid drag can be adjusted utilizing the relative positioning of casing collars and tool joints. The total fluid drag can be summed with the other force factors, such as a shear force and mechanical drag. The total drag can then be utilized as the overpull force applied to the stuck drill string.
1 . A method, comprising:
receiving input parameters of at least a torque parameter and a drag parameter for a drill string, wherein the drill string is in a stuck state in a borehole and the receiving is at a time when at least some material sag of a drilling mud, located outside of the drill string, has occurred at a first depth at a downhole location in the borehole; and
determining a backoff depth at which to conduct a back-off operation of the drill string using the first depth threshold and an overpull force to be applied to a drill string hook coupled to the drill string for that backoff depth, comprising:
ascertaining a percentage of liquid of the drilling mud at the first depth and a percentage of solids of the drilling mud that have settled out due to the at least some material sag at the first depth;
computing a first insitu friction parameter utilizing the percentage of liquid and a second insitu friction parameter utilizing the percentage of solids;
calculating a total drag utilizing terms that include a mechanical drag, the first insitu friction parameter, the second insitu friction parameter, and a fluid drag of a fluid inside the drill string, wherein each of the terms is calculated over a length of a portion of the drill string being evaluated; and
generating the overpull force utilizing the total drag to update the torque parameter and the drag parameter, wherein the overpull force is sufficient to move the drill string from the stuck state.
2 . The method as recited in claim 1 , further comprising:
communicating the overpull force to a well site controller, a drilling controller, or a user; and
adjusting a drilling operation of the borehole using the overpull force.
3 . The method as recited in claim 1 , further comprising:
initiating a drill string stuck remediation utilizing the overpull force.
4 . The method as recited in claim 1 , further comprising:
producing a visualization of the overpull force.
5 . The method as recited in claim 1 , wherein the generating further comprises:
identifying a safety factor utilizing the overpull force, wherein the safety factor is used by a drilling operation for decision making.
6 . The method as recited in claim 1 , wherein the determining further comprises:
evaluating a deeper backoff depth until a maximum depth is identified where the drill string can be safely pulled out of the borehole by the drill string hook, wherein the deeper backoff depth is determined by a parameter included with the input parameters.
7 . The method as recited in claim 1 , wherein the determining is repeated for a second depth within the borehole.
8 . The method as recited in claim 7 , wherein the first depth and the second depth represent a range of depths.
9 . The method as recited in claim 1 , further comprising:
transforming the input parameters utilizing a machine learning system or a deep neural network system; and
wherein the terms for the total drag calculation further includes one or more of an inside friction parameter at the first depth, a shear force at the first depth, or an outside friction at the first depth.
10 . The method as recited in claim 1 , wherein the input parameters comprise at least one of a fluid composition of the mud at the first depth, a pressure parameter at the first depth, a temperature parameter at the first depth, a casing wear at the first depth, a relative position of casing collars to the first depth, a relative position of tool joints to the first depth, a material sag parameter at the first depth, a bonding characteristic of borehole materials of the mud, or a borehole geometry at the first depth.
11 . The method as recited in claim 10 , further comprising:
determining the fluid composition utilizing laboratory testing or borehole logging tools.
12 . The method as recited in claim 1 , wherein at least one of the receiving, the determining, the ascertaining, the computing, the calculating, or the generating is encapsulated as a function or a microservice accessible by other functions or microservices.
13 . A system, comprising:
a data transceiver, capable of receiving input parameters from one or more of downhole sensors of a borehole undergoing drilling operations, surface sensors proximate the borehole, a data store, a previous survey data, a well site controller, a drilling controller, or a computing system, wherein the input parameters include sensor data of a fluid composition of a mud at a first depth in the borehole, a drill string is coupled to a surface location and extends into the borehole, the drill string is in a stuck state, and wherein the fluid composition comprises a percentage of liquid of the mud and a percentage of solids of the mud that have settled out of the mud at a time when at least some material sag has occurred at the first depth;
a result transceiver, capable of communicating an output parameter; and
a pull force processor, capable of using at least one of the input parameters and a first insitu friction parameter and a second insitu friction parameter to generate the output parameter, wherein a first insitu friction parameter is determined from the percentage of liquid and the second insitu friction parameter is determined from the percentage of solids, and calculating a total drag utilizing terms that include a shear force, the first insitu friction parameter, the second insitu friction parameter, and a fluid drag of a fluid inside the drill string, wherein each of the terms is calculated over a length of a portion of the drill string being evaluated, and where the output parameter comprises at least an overpull force and a backoff depth, the overpull force is sufficient to conduct a back-off operation of the drill string at the backoff depth, the overpull force is applied to a drill string hook coupled to the drill string, and the overpull force utilizes a safety factor.
14 . The system as recited in claim 13 , wherein the drilling controller is capable of receiving the output parameter and of initiating a remediation operation utilizing the overpull force.
15 . The system as recited in claim 13 , wherein the data transceiver, the result transceiver, and the pull force processor is part of one or more of the well site controller, the drilling controller, a geo-steering system, a bottom hole assembly, or the computing system.
16 . The system as recited in claim 13 , wherein the output parameter further comprises a visualization of the overpull force, a threshold depth, or the backoff depth, and a user initiates a remediation utilizing the output parameter.
17 . The system as recited in claim 13 , wherein the pull force processor is further capable of utilizing a machine learning system or a deep neural network system to transform the input parameters.
18 . The system as recited in claim 13 , wherein the data transceiver receives input parameters at one or more additional depths or depth ranges.
19 . The system as recited in claim 13 , wherein the fluid composition is determined utilizing laboratory testing.