# US 12,000,281 B2 · Horizontal directional drilling system with improved system for limiting torque > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,000,281 B2 - Document ID: US12000281B2 - Status: Granted - Kind: B2 - Application number: 17/946,123 - Filed: 2022-09-16 - Published: 2023-03-16 - Granted: 2024-06-04 - Earliest claimed: 2021-09-16 - Assignees: Vermeer Manufacturing Company - Applicants: Vermeer Manufacturing Company - Inventors: Zach Buckley; Jason Morgan - Web page: https://patentgrep.com/patent/US12000281B2 ## CPC - E21B 7/046: {horizontal drilling (drilling with mechanical conveying means E21B7/003)} - E21B 15/04: specially adapted for directional drilling, e.g. slant hole rigs - E21B 19/08: Apparatus for feeding the rods or cables (E21B19/22 takes precedence; automatic feed E21B44/02); Apparatus for increasing or decreasing the pressure on the drilling tool; Apparatus for counterbalancing the weight of the rods - E21B 19/166: {Arrangements of torque limiters or torque indicators} - E21B 44/04: in response to the torque of the drive {; Measuring drilling torque (E21B44/06 takes precedence; measuring stresses in a well bore pipe E21B47/007)} - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract A method of controlling a horizontal directional drill having a rotary drive system. The rotary drive system includes a variable displacement pump providing pressurized fluid to a motor, a displacement control that adjusts motor displacement, a torque limiter valve that opens at a torque limit to provide pressurized fluid to the displacement control to allow the system to limit torque, and cross-port relief valves that open at a cross-port relief pressure to limit pressure applied across a motor inlet and a motor outlet. The method includes adjusting the torque limiter pressure to vary the maximum torque applied to a drill string based on operating parameters of the horizontal direction drill, and adjusting the cross-port relief pressure to be higher than the torque limiter pressure each time that the torque limiter pressure is adjusted. ## Claims ### Claim 1 A drilling machine having a rotary drive for applying torque to a drill string and a system for controlling the torque, the system comprising: a controller having an operator input that allows an operator to specify an operating torque limit; a variable displacement hydraulic pump that provides hydraulic fluid to a motor at a variable flow rate; a torque limiter valve that provides hydraulic fluid to de-stroke the pump when a pressure of the hydraulic fluid provided to the motor is equal to a first predetermined set point, wherein the first predetermined set point is adjustable; a cross-port relief that allows hydraulic fluid to bypass the motor when a pressure of the hydraulic fluid provided to the motor is equal to a second predetermined set point; wherein the controller automatically adjusts the first predetermined set point to a setting for a make-up torque, wherein a torque limit is set at a level for proper make-up during a drill string make-up process, or to a setting for the operating torque limit during a boring process; and wherein the controller automatically adjusts the second predetermined set point to be a predetermined amount higher than the first predetermined set point. ### Claim 2 (depends on 1) The drilling machine of claim 1, wherein the second predetermined set point is 300 to 500 psi higher than the first predetermined set point. ### Claim 3 (depends on 1) The drilling machine of claim 1, wherein the controller further comprises a vise clamp input indicating that a vise of the drilling machine is clamping the drill string, and wherein the controller automatically adjusts the first predetermined set point to the setting for a make-up torque when the controller receives the vise clamp input. ### Claim 4 (depends on 3) The drilling machine of claim 3, wherein the controller automatically adjusts the first predetermined set point to a setting for the operating torque limit when the vise clamp input is not received at the controller. ### Claim 5 (depends on 3) The drilling machine of claim 3, wherein the controller is further operable to selectively automatically adjust the first predetermined set point to a setting for a break-out torque when the controller receives the vise clamp input. ### Claim 6 (depends on 1) The drilling machine of claim 1, wherein the torque limiter valve is located adjacent the variable displacement hydraulic pump in a power unit housing of the drilling machine, and wherein the cross-port relief is located adjacent the motor on a movable carriage of the drilling machine. ### Claim 7 (depends on 6) The drilling machine of claim 6, wherein the torque limiter valve and the cross-port relief are in fluid communication with one another via hydraulic fluid hoses. ### Claim 8 A method of controlling a horizontal directional drill having a rotary drive system for applying torque to a drill string, the rotary drive system including a variable displacement pump providing pressurized fluid to a motor that generates the torque, a displacement control that adjusts motor displacement to limit flow to maintain a controlled pressure, a torque limiter valve that opens at a torque limit pressure to provide pressurized fluid to the displacement control to allow the system to limit torque when a system pressure is equal to a pressure that will generate a desired maximum torque, and cross-port relief valves that open at a cross-port relief pressure to limit pressure applied across a motor inlet and a motor outlet, the method comprising: adjusting the torque limiter pressure to set the maximum torque applied to the drill string based on operating parameters of the horizontal direction drill; and adjusting the cross-port relief pressure to be higher than the torque limiter pressure each time that the torque limiter pressure is adjusted. ### Claim 9 (depends on 8) The method of claim 8, wherein adjusting the cross-port relief pressure to be higher than the torque limiter pressure includes adjusting the cross-port relief pressure to be 300 to 500 psi higher than the torque limiter pressure. ### Claim 10 (depends on 8) The method of claim 8, wherein the pressure limiter valve and the cross-port relief valves are controlled electronically and the horizontal directional drill further comprises a control system with an operator input and with an input indicating the status of a vise configured to clamp the drill string, the method further comprising: automatically adjusting the torque limiter pressure when the vise clamps the drill string to set a make-up torque, and in response also adjusting the cross-port relief pressure to be higher than the torque limiter pressure set for the make-up torque; and automatically adjusting the torque limiter pressure to a pressure that corresponds to an operator selected maximum torque when the vise is not clamping the drill string, and in response also adjusting the cross-port relief pressure to be higher than the torque limiter pressure corresponding to the operator selected maximum torque. ### Claim 11 (depends on 10) The method of claim 10, wherein adjusting the cross-port relief pressure to be higher than the torque limiter pressure set for the make-up torque includes adjusting the cross-port relief pressure to be 300 to 500 psi higher than the torque limiter pressure; and wherein adjusting the cross-port relief pressure to be higher than the torque limiter pressure corresponding to the operator selected maximum torque includes adjusting the cross-port relief pressure to be 300 to 500 psi higher than the torque limiter pressure. ### Claim 12 (depends on 8) The method of claim 8, wherein the pressure limiter valve and the cross-port relief valves are controlled electronically and the horizontal directional drill further comprises a control system with an operator input and with an input indicating the status of a vise configured to clamp the drill string, the method further comprising: automatically adjusting the torque limiter pressure when the vise clamps the drill string to set a break-out torque, and in response also adjusting the cross-port relief pressure to be higher than the torque limiter pressure set for the break-out torque; and automatically adjusting the torque limiter pressure to a pressure that corresponds to an operator selected maximum torque when the vise is not clamping the drill string, and in response also adjusting the cross-port relief pressure to be higher than the torque limiter pressure corresponding to the operator selected maximum torque. ### Claim 13 (depends on 12) The method of claim 12, wherein adjusting the cross-port relief pressure to be higher than the torque limiter pressure set for the break-out torque includes adjusting the cross-port relief pressure to be 300 to 500 psi higher than the torque limiter pressure; and wherein adjusting the cross-port relief pressure to be higher than the torque limiter pressure corresponding to the operator selected maximum torque includes adjusting the cross-port relief pressure to be 300 to 500 psi higher than the torque limiter pressure. ### Claim 14 (depends on 8) The method of claim 8, wherein the horizontal directional drill has a variable displacement motor having a plurality of operating modes, the method comprising automatically adjusting the torque limiter pressure as a function of the operating mode of the variable displacement motor, and in response automatically adjusting the cross-port relief pressure. ### Claim 15 A drilling machine having a rotary drive for applying torque to a drill string and a system for controlling the torque, the system comprising: a variable displacement hydraulic pump that provides hydraulic fluid to a motor at a variable flow rate; a controller having an input provided by a pressure sensor configured to read a hydraulic pressure of the fluid provided to the motor, the controller configured to provide a current signal to the hydraulic pump to de-stroke the pump when a pressure of the hydraulic fluid provided to the motor is equal to a first predetermined set point, wherein the first predetermined set point is adjustable; a cross-port relief that allows hydraulic fluid to bypass the motor when a pressure of the hydraulic fluid provided to the motor is equal to a second predetermined set point; wherein the controller automatically adjusts the first predetermined set point to a setting for a make-up torque, wherein a torque limit is set at a level for proper make-up during a drill string make-up process, or to a setting for an operating torque limit during a boring process; and wherein the controller automatically adjusts the second predetermined set point to be a predetermined amount higher than the first predetermined set point. ### Claim 16 (depends on 15) The drilling machine of claim 15, wherein the second predetermined set point is 300 to 500 psi higher than the first predetermined set point. ### Claim 17 (depends on 15) The drilling machine of claim 15, wherein the controller further comprises a vise clamp input indicating that a vise of the drilling machine is clamping the drill string, and wherein the controller automatically adjusts the first predetermined set point to the setting for a make-up torque when the controller receives the vise clamp input. ### Claim 18 (depends on 17) The drilling machine of claim 17, wherein the controller automatically adjusts the first predetermined set point to a setting for the operating torque limit when the vise clamp input is not received at the controller. ### Claim 19 (depends on 17) The drilling machine of claim 17, wherein the controller is further operable to selectively automatically adjust the first predetermined set point to a setting for a break-out torque when the controller receives the vise clamp input.