# US 11,016,466 B2 · Method of designing and optimizing fixed cutter drill bits using dynamic cutter velocity, displacement, forces and work > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,016,466 B2 - Document ID: US11016466B2 - Status: Granted - Kind: B2 - Application number: 15/573,136 - Filed: 2016-05-11 - Published: 2018-03-29 - Granted: 2021-05-25 - Earliest claimed: 2015-05-11 - Assignees: Schlumberger Technology Corporation - Applicants: Smith International, Inc. - Inventors: Andrew Dow; Crystal Brown Mayer; Carlos Alberto Armada; Balasubramanian Durairajan - Web page: https://patentgrep.com/patent/US11016466B2 ## CPC - G05B 19/31: for continuous-path control - E21B 10/00: Drill bits (specially adapted for deflecting the direction of boring {E21B7/064}; with means for collecting substances E21B27/00) - E21B 10/46: characterised by wear resisting parts, e.g. diamond inserts - E21B 41/00: Equipment or details not covered by groups E21B15/00 - E21B40/00 - E21B 49/00: Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells - G01N 3/58: Investigating machinability by cutting tools; Investigating the cutting ability of tools - E21B 7/067: {with means for locking sections of a pipe or of a guide for a shaft in angular relation, e.g. adjustable bent sub} - E21B 10/54: the bit being of the rotary drag type, e.g. fork-type bits - E21B 17/1078: {Stabilisers or centralisers for casing, tubing or drill pipes (E21B17/1007 - E21B17/1064 take precedence)} - G01N 2203/0212: Theories, calculations - G05B 2219/36363: Tool change time as function of cutter trajectory, spindle and slide times - G05B: CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS (systems for controlling or regulating non-electric variables G05D; systems for regulating electric or magnetic variables G05F; control devices or systems insofar as characterised by mechanical features only G05G) - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) ## Abstract A method includes simulating a cutting tool drilling an earth formation by incrementally rotating the cutting tool at a plurality of time intervals, determining a true trajectory of a cutting element disposed on the cutting tool for the duration of the plurality of time intervals, and determining a dynamic work profile for the cutting element based on the true trajectory and a force acting on the cutting element at each time interval. ## Claims ### Claim 1 A method, comprising: simulating a cutting tool drilling an earth formation, comprising incrementally rotating the cutting tool at a plurality of time intervals; determining a trajectory of the cutting tool to model at least a portion of a section of a wellbore; determining a true trajectory of a cutting element disposed on the cutting tool for a duration of the plurality of time intervals, wherein determining the true trajectory of the cutting element is conducted separately from determining the trajectory of the cutting tool; and determining a dynamic work profile for the cutting element based on the true trajectory and a force acting on the cutting element at each time interval. ### Claim 2 (depends on 1) The method of claim 1, further comprising displaying the dynamic work profile in a graphical display. ### Claim 3 (depends on 1) The method of claim 1, further comprising: determining a second dynamic work profile for a second cutting element disposed on the cutting tool; and comparing the dynamic work profile to the second dynamic work profile. ### Claim 4 (depends on 3) The method of claim 3, further comprising: identifying which cutting element performs greater dynamic work over the duration for the plurality of time intervals; and altering at least one cutting tool parameter corresponding to a location of the identified cutting element. ### Claim 5 (depends on 1) The method of claim 1, further comprising determining at least one of an average amplitude, an average frequency and an average duration of the dynamic work profile. ### Claim 6 (depends on 5) The method of claim 5, further comprising conducting finite element analysis on a simulated cutting element subjected to the average amplitude, the average frequency and the average duration of the dynamic work profile. ### Claim 7 (depends on 1) The method of claim 1, further comprising: modifying at least one simulation parameter selected from a group consisting of drilling performance parameters, drilling operating parameters and bottom hole assembly parameters; and repeating simulating, determining a true trajectory, determining a dynamic work and modifying the simulation parameters until the dynamic work on one or a plurality of cutting elements either increases or decreases. ### Claim 8 (depends on 1) The method of claim 1, further comprising determining the force acting on the cutting element during each of the plurality of time intervals. ### Claim 9 A method of designing a bottom hole assembly, comprising: simulating drilling an earth formation using the bottom hole assembly; determining one or more cutting elements subjected to cyclic loading, wherein determining the one or more cutting elements subjected to cyclic loading comprises: determining a force output on the one or more cutting elements; determining a true trajectory of the one or more cutting elements, wherein the true trajectory includes a cutter position, a cutter displacement, and a cutter velocity over a time period; and determining a dynamic work profile for the one or more cutting elements, wherein the dynamic work profile is determined using the true trajectory including the force output and the cutter displacement or the cutter velocity; altering at least one input parameter selected from a group consisting of cutting tool parameters, drilling operating parameters and bottom hole assembly parameters; and repeating simulating, determining and altering until a desired cutting tool design is reached having reduced cyclic loading, increased distribution of dynamic work profile, or any combination thereof. ### Claim 10 (depends on 9) The method of claim 9, wherein altering at least one input parameter comprises shoulder shape, number of cutting elements, cutting element impact resistance, cutting element fatigue strength, cutting element shape, cutting element layout, cutting element back rake and cutting element side rake. ### Claim 11 (depends on 9) The method of claim 9, further comprising conducting finite element analysis on a simulated cutting element subjected to the cyclic loading. ### Claim 12 (depends on 9) The method of claim 9, further comprising evaluating a physical cutting element by subjecting the cutting element to the cyclic loading. ### Claim 13 (depends on 9) The method of claim 9, further comprising displaying the cyclic loading of one of the cutting elements in a graphical display. ### Claim 14 (depends on 9) The method of claim 9, wherein altering comprises altering at least one characteristic of a bent motor in the bottom hole assembly selected from a second group consisting of a bend angle and a motor diameter. ### Claim 15 (depends on 9) The method of claim 9, wherein altering comprises altering at least one stabilizer parameter selected from a second group consisting of adding a stabilizer to the bottom hole assembly, altering a stabilizer placement, and altering a stabilizer type. ### Claim 16 (depends on 9) The method of claim 9, further comprising determining an average amplitude, an average frequency and an average duration of the cyclic loading. ### Claim 17 A bottom hole assembly comprising: a cutting tool having a tool body; a first cutting element disposed on the tool body in a first region subjected to a first cyclic loading profile in a simulation of the bottom hole assembly, wherein the first region is proximate to a gage region of the cutting tool; and a second cutting element disposed on the tool body in a second region subjected to a second cyclic loading profile in the simulation of the bottom hole assembly, wherein the first cyclic loading profile has one or more of a greater average amplitude, a greater average frequency, and a greater average duration relative to the second cyclic loading profile, and the second region is proximate to a central axis of the cutting tool; the first cutting element having a greater impact resistance than the second cutting element, and the second cutting element having a greater wear resistance than the first cutting element. ### Claim 18 (depends on 17) The bottom hole assembly of claim 17, wherein the tool body is coupled to a drill string having a bent section. ### Claim 19 (depends on 18) The bottom hole assembly of claim 18, wherein the bent section has an adjustable bend angle. ### Claim 20 (depends on 17) The bottom hole assembly of claim 17, further comprising at least one stabilizer along a drill string coupled to the cutting tool. ### Claim 21 (depends on 9) The method of claim 9, wherein simulating drilling includes determining bottom hole assembly displacement, bottom hole assembly rotation, and the force output, and wherein determining the cutter position, the cutter displacement, and the cutter velocity are determined based on the bottom hole assembly displacement and the bottom hole assembly rotation. ### Claim 22 (depends on 21) The method of claim 21, wherein determining the true trajectory of the cutting element is conducted separately from determining the bottom hole assembly displacement and the bottom hole assembly rotation.