Patent Publication Number: US-2023142057-A1

Title: Transmission Shaft Brake for Engine Auto Restart

Description:
BACKGROUND 
     The present disclosure relates to hydraulic fracturing pumps. In particular, the present disclosure relates to systems and methods for controlling one or more hydraulic fracturing pumps that are stationary while in operation. 
     Hydraulic fracturing pump systems oftentimes include diesel engines coupled to reciprocating pumps or frac pumps. These hydraulic fracturing pump systems may include an engine standby controller (or ESC) system. These ESC systems may be configured to shut down the diesel engine when it is not in use to reduce diesel fuel consumption and emissions output. When the diesel engine is off, an ESC system may utilized one or more batteries to power certain auxiliary systems ensure the diesel engine can quickly restart when needed. 
     When restarting the engine, there is risk that the shaft may rotate, causing unwanted pressure on the power end of the pump which is a potential safety hazard. To prevent this, the hydraulic fracturing pump systems are oftentimes equipped with a brake, such as a disc brake mounted to a shaft coupled to the pump or an internal brake gear set by a combination of gears inside a gearbox coupled to the pump, which is actuated by hydraulic pressure. The hydraulic pressure can be supplied by the engine when it is in idle, but when an ESC system shuts down the engine there may be insufficient hydraulic pressure necessary to engage the brake, which is needed for the engine to restart in safe manner. What is needed, therefore, is an improved system and method for providing power to a brake configured to stop a pump when the engine used to power the brake is idled or stationary. 
     BRIEF SUMMARY 
     A method for controlling a hydraulic fracturing pumping system is described herein. The method can include stopping an engine coupled to a hydraulic fracturing pumping system including at least one pump by supplying pressure from an accumulator to a hydraulic braking system including a brake. The method can also include starting the engine coupled to the hydraulic fracturing pumping system and releasing the brake. 
     A hydraulic fracturing pumping system is also described herein. The hydraulic fracturing pumping system can also include a first pump coupled to an engine via a transmission and a second pump coupled to the transmission, wherein the second pump is a hydraulic pump. The hydraulic fracturing pumping system can also include an accumulator coupled to the hydraulic pump. The accumulator can be configured to store hydraulic pressure generated via the hydraulic pump. The hydraulic fracturing pumping system can also include a hydraulic brake system coupled to the accumulator. 
     A hydraulic fracturing pumping system disposed on a trailer is also described herein. The hydraulic fracturing pumping system can include a diesel engine, a transmission, a hydraulic pump coupled to the transmission, and a transmission oil reservoir coupled to the transmission. The hydraulic fracturing pumping system can also include a reciprocating plunger pump, a shaft mechanically linking the transmission to the reciprocating plunger pump, and an accumulator in fluid communication hydraulic pump. The accumulator can be configured to store hydraulic pressure generated via the hydraulic pump. A hydraulic brake system can be coupled to the accumulator. 
     It will be appreciated that this summary is intended merely to introduce some aspects of the present methods, systems, and media, which are more fully described and/or claimed below. Accordingly, this summary is not intended to be limiting. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention may best be understood by referring to the following description and accompanying drawings that are used to illustrate embodiments of the invention. In the drawings: 
         FIG.  1    illustrates a schematic showing components of a frac pump trailer containing a brake, according to an embodiment. 
         FIG.  2    illustrates a schematic showing hydraulic control of a conventional brake system. 
         FIG.  3    illustrates a schematic showing hydraulic control of a brake system when an engine is stationary, according to an embodiment. 
         FIG.  4    illustrates a flow chart of a method for operating the brake system of  FIG.  3   , according to an embodiment. 
         FIG.  5 A  illustrates a schematic showing hydraulic control of the brake system illustrated in  FIG.  3    when the pump trailer is operating at step  402  of the method illustrated by  FIG.  4   . 
         FIG.  5 B  illustrates a schematic showing hydraulic control of the brake system illustrated in  FIG.  3    when the pump trailer is operating at step  404  of the method illustrated by  FIG.  4   . 
         FIG.  5 C  illustrates a schematic showing hydraulic control of the brake system illustrated in  FIG.  3    when the pump trailer is operating at step  406  of the method illustrated by  FIG.  4   . 
         FIG.  5 D  illustrates a schematic showing hydraulic control of the brake system illustrated in  FIG.  3    when the pump trailer is operating at step  408  of the method illustrated by  FIG.  4   . 
         FIG.  5 E  illustrates a schematic showing hydraulic control of the brake system illustrated in  FIG.  3    when the pump trailer is operating at step  410  of the method illustrated by  FIG.  4   . 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to specific embodiments illustrated in the accompanying drawings and figures. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the embodiments described herein. However, it will be apparent to one of ordinary skill in the art that other embodiments may be practiced without these specific details. In other instances, well-known methods, procedures, components, circuits, and networks have not been described in detail so as not to unnecessarily obscure aspects of the embodiments. 
       FIG.  1    illustrates a schematic showing components of a pump trailer  100  containing a brake  102 . The brake  102  can be coupled or otherwise attached to a shaft  104 . The shaft  104  can have a first end  106  and a second end  108 . The brake  102  can be a disc brake, containing a rotor and a caliper, a drum brake, any other suitable brake device. The second end  108  of the shaft  104  can be coupled to one or more pumps  110 , such as frac pumps or reciprocating plunger pumps. The first end  106  of the shaft  104  can be coupled to an engine  112 , optionally via a transmission  114 . As shown in  FIG.  1   , a hydraulic pump  116  can be configured to provide hydraulic pressure suitable to actuate the brake  102  via one or more hydraulic lines  118  when the engine  112  is in use. In one or more embodiments, the hydraulic pump  116  can be located on or in the transmission  114  and the pressure needed to set the brake  102  can be supplied by the hydraulic pump  116  when the engine  112  is running at idle speeds or greater. The hydraulic pump  116  can be used to pump a transmission oil suitable for actuating the brake  102 . As used herein, the term “transmission oil” means any fluid containing a mineral oil that is suitable for use as a hydraulic fluid, transmission fluid, transmission oil, or brake fluid. 
     The engine  112  can be or include any suitable internal combustion engine. In one or more embodiments, the engine  112  can be a diesel engine, a dual-fuel engine (natural gas and diesel), or a turbine. In other embodiments, the engine  112  can be or include an electric motor. The electric motor can be configured to withstand an oilfield environment. 
     The pump  110  can be or include any pump suitable for pumping a fracturing fluid or gravel pack fluid into a wellbore and/or its surrounding subterranean formation. In one or more embodiments, the pump  110  can be or include a positive displacement pump, a plunger pump, or a reciprocating pump. For example, the pump  110  can be a triplex pump or a quintuplex pump each configured to provide a power output of about 1,000 HP, about 1,500 HP or about 2,000 HP to about 2,500 HP, about 3,000 HP, or about 5,000 HP or more. 
     As illustrated in  FIG.  1   , the engine  112  can be disposed along with the pump  110  on a single vehicle, such as a trailer. In other embodiments (not shown), the engine  112  vehicle or platform separate and distinct from a vehicle or platform supporting the pump  110 . Engines  112 , pumps  112 , and configurations of same suitable for use in the present disclosure are described in U.S. Pat. Nos. 7,845,413, 8,997,904, 9,103,193, 9,140,110, 9,395,049, 9,683,432, and 10,927,802, each of which is incorporated by reference herein in its entirety. 
       FIG.  2    illustrates a schematic showing hydraulic control of a conventional brake system  200 . The brake system  200  can include a brake caliper  202 , a three-way solenoid valve  204 , a pressure gauge  206 , the hydraulic pump  116 , and a reservoir  208 . As shown, the brake caliper  202  can be in fluid communication with the three-way solenoid valve  204 , the pressure gauge  206 , the hydraulic pump  116 , and the reservoir  208  via the hydraulic lines  118 . Transmission oil can be stored in the reservoir  208 . The hydraulic pump  116  can be in fluid communication with the reservoir  208  and the hydraulic pump  116  can be configured to pump the transmission oil from the reservoir  208  to the three-way solenoid valve  204 . The three-way solenoid valve  204  can be a three-way solenoid valve configured to direct transmission oil back to the reservoir  208  when the three-way solenoid valve  204  is closed or direct the transmission oil to the brake caliper  202  when the three-way solenoid valve  204  is open. 
     When the engine  112  is running, the hydraulic pump  116  located on or in the transmission  114  can be configured to provide a pressure in the hydraulic lines  118  sufficient to actuate the brake caliper  202 . In particular, when a brake signal is set or is otherwise transmitted, the three-way solenoid valve  204  opens to allow transfer of transmission oil from the reservoir  208  to the brake caliper  202  under a pressure sufficient to actuate the brake caliper  202 . When the brake signal is not set, the three-way solenoid valve  204  returns to the closed position. When the three-way solenoid valve  204  is closed, transmission oil supplied from the reservoir  208  and hydraulic pump  116  is recycled and discharged to the reservoir  208  through the three-way solenoid valve  204 . When the engine  112  is not in use or is otherwise stationary, the hydraulic pump  116  can be unable to provide the pressure in the hydraulic lines  118  sufficient to actuate the brake caliper  202 . 
       FIG.  3    illustrates a schematic showing hydraulic control of a brake system  300  for when an engine  112  is stationary. As shown in  FIG.  3   , the brake system  300  can include an accumulator device  302  coupled with, connected to, or otherwise fluidically linked with an existing brake system, such as the conventional brake system  200 . The accumulator device  302  can include an accumulator  304 , a pressure sensor  306 , a safety block  308 , and a check valve  310 . The accumulator  304  can be or include any suitable accumulator device. For example, the accumulator  304  can be or include any suitable vessel, cylinder, or chamber configured to maintain a preset or fixed hydraulic pressure therein. The check valve  310  can be disposed downstream from the hydraulic pump  116  so that, when the engine  112  is in operation, the hydraulic pump  116  is capable of operating to subject the transmission oil to a pressure sufficient to engage the check valve  310  in an open position, thereby permitting the transmission oil to pass therethrough. Transmission oil passing through the check valve  310  then enters the safety block  308 . 
     The safety block  308  can include a first valve  312 , a second valve  314 , an overflow valve  316 , and a two-way solenoid valve  318 . The first valve  312  and second valve  314  can each be or include any suitable valve apparatus, such as a manually actuated valve. For example, the first valve  312  and the second valve  314  can each be or include a ball valve. As shown in  FIG.  3   , the first valve  312 , second valve  314 , overflow valve  316 , and two-way solenoid valve  318  can be fluidically linked to each other and arranged in a parallel configuration. 
     When the pump trailer  100  is operating in the field, the first valve  312  remains in an open position while the second valve  314  and the two-way solenoid valve  318  remain in a closed position. In this arrangement, the transmission fluid entering the safety block  308  passes through the open first valve  312  and into the accumulator  304 . The transmission oil will continue to enter into the accumulator  304  until the accumulator  304  is charged to a preset pressure or other suitable pressure, for example a pressure sufficient to actuate the brake caliper  202 . In one or more embodiments, the accumulator  304  can be configured to be charged with transmission oil to a pressure of at least about 100 kPa, at least about 250 kPa, at least about 500 kPa, at least about 1,000 kPa, or at least about 1,500 kPa. For example, the accumulator  304  can be charged with transmission oil at a pressure from about 500 kPa, about 1,000 kPa, or about 1,500 kPa to about 2,000 kPa, about 3,500 kPa, or about 5,000 kPa. 
     The three-way solenoid valve  204  can be disposed downstream of the check valve  310 . As shown in  FIG.  3   , the fluid line can split downstream of the check valve  310  and connect into the three-way solenoid valve  204  so that at least a portion of the pressurized transmission oil leaving the hydraulic pump  116  can be introduced to the three-way solenoid valve  204 . The transmission oil introduced to the three-way solenoid valve  204  can be directed back to the reservoir  208  when the three-way solenoid valve  204  is closed or to the brake caliper  202  when the three-way solenoid valve  204  is open. This configuration enables the brake caliper  202  to be set at any time when the engine  112  is in operation. 
     When the engine  112  is stationary, the pressurized transmission oil in the accumulator  304  can be released upon input of a brake signal. The released transmission oil exiting the accumulator  304  can then pass through the open first valve  312  and into a line in open fluid communication with the three-way solenoid valve  204 . The released transmission oil introduced to the three-way solenoid valve  204  can be directed back to the reservoir  208  when the three-way solenoid valve  204  is closed or to the brake caliper  202  when the three-way solenoid valve  204  is open. This configuration enables the brake caliper  202  to be set when the engine  112  is stationary. The overflow valve  316  is disposed in the safety block  302  so that the transmission oil pumped by the hydraulic pump  116  and/or released from the accumulator  304  is maintained at a pressure of about 10 bar, about 12 bar, or about 14 bar to about 18 bar, about 20 bar, or about 25 bar or any other pressure sufficient to actuate the brake caliper  202 . 
     In one or more embodiments, the engine  112  can be stationary as a result of being in a standby mode. For example, the engine  112  can be in a standby mode brought about by an automatic standby system, such as an engine standby controller (ESC). Examples of suitable ESCs are described in U.S. Pat. Nos. 10,358,989, 10,371,113, and 10,570,868, each of which is incorporated by reference herein in its entirety. The ESC can be disposed on the trailer  100  and coupled to the engine  112 . In one or more embodiments, the engine  112  electrically connected to or at least partially controlled by an ESC can be placed in a standby mode, during which the pressurized transmission oil in the accumulator  304  can be utilized as needed to achieve a transmission oil pressure sufficient to actuate the brake caliper  202  upon input of a brake signal. 
     When the engine  112  is turned off and a main switch is turned off (resulting in a loss of power to the brake system  300 ), the accumulator  304  and safety block  302  can be drained of any remaining transmission oil, thereby enabling maintenance or removal of any portion of the brake system  300 . The accumulator  304  and safety block  302  can be drained of the transmission oil by opening the two-way solenoid valve  318  to allow transmission oil to pass therethrough and ultimately into the reservoir  208 . The accumulator  304  and safety block  302  can also be drained of the transmission oil by opening the second valve  314  to allow the transmission oil to pass therethrough and ultimately into the reservoir  208 . 
       FIG.  4    illustrates a flow chart of a method  400  for operating the brake system  300 . The method  400  can include an initial step in which the main power switch, or mainswitch (not shown), of the pump trailer  100  is on and the engine  112  is on, as at  402 . The transmission  114  and shaft  104  are also rotating in step  402 . Step  402  can be or include a mode of operation when the engine  112  is on and operating the pump  110 . Next, the brake  102  can be set (by actuating the brake caliper  202 ) so that the transmission  114  and shaft  104  are not rotating or are stationary, as at  404 . Also, at step  404 , the pump  110  is stationary. In the next mode of operation, the engine  112  is shut off while the mainswitch remains on, as at  406 . In step  406 , the brake  102  is not set and the transmission  114  is in neutral. Next, the brake  102  is set while the engine  112  is shut off and the mainswitch remains on, as at  408 . At step  408 , the brake  102  is set at a force sufficient to prevent rotation of the transmission  114  and the shaft  104  so that both transmission  114  and the shaft  104  are stationary. 
     The engine  112  can be shut off by virtue of being in a standby mode, for example, a standby mode induced by an ESC, when the engine  112  is electrically connected to or at least partially controlled by an ESC. When the engine  112  is placed in a standby mode or is otherwise shut off, the pressurized transmission oil in the accumulator  304  can be utilized as needed to achieve a transmission oil pressure sufficient to actuate the brake caliper  202  upon input of a brake signal. In one or more embodiments, the pressure sensor  306  can communicate or send a signal to the ESC indicating when the accumulator  304  is fully charged or otherwise at a pressure sufficient to actuate the brake  102 . The ESC can be configured to place the engine  112  in a standby mode only when the pressure sensor  306  detects a sufficient transmission oil pressure in the accumulator  304 . 
     After step  408 , the engine  112  and the mainswitch can be turned off so that the accumulator can be drained, as at  410 . When the pump trailer  100  is at step  410  it is considered to be “turned off” or otherwise in an “off” state or configuration. To turn the pump trailer  100  and its engine  112  back on, a user can first turn the mainswitch back on via step  412 , as at  408 , and then engine  112  can be turned back on via step  414 , as at  402 , with steps  402 - 414  being repeated as desired. 
       FIGS.  5 A- 5 E  illustrate modes of operation of the brake system  300  when the brake system  300  is operating in accordance with method  400  illustrated by  FIG.  4   .  FIG.  5 A  illustrates a schematic showing hydraulic control of the brake system illustrated in  FIG.  3    when the pump trailer is operating at step  402  of the method  400 . At step  402 , as indicated in  FIG.  5 A , the engine  112  is running and the transmission  114  is rotating such that the hydraulic pump  116  is pressurizing the transmission oil in the hydraulic lines and through the check valve  310  so that a first portion of the transmission oil is introduced to the safety block  308  and the accumulator  304  and a second portion of the transmission oil is introduced to the three-way solenoid valve  204 . In this mode of operation illustrated in  FIG.  5 A , the three-way solenoid valve  204  is closed so that the brake  102  is not set by the pressure of the second portion of the transmission oil and the transmission continues to rotate and drive, or otherwise provide energy to, the hydraulic pump  116 . Also, during the mode of operation illustrated in  FIG.  5 A , the first portion of transmission oil passing through the safety block  308  continues to charge the accumulator  304  until the accumulator  304  is full or until a pre-set or desired pressure is reached inside the accumulator  304 . 
     A user or a control system can then engage the brake  102 , as at step  402 .  FIG.  5 B  illustrates a schematic showing hydraulic control of the brake system illustrated in  FIG.  3    when the pump trailer is operating at step  404  of the method illustrated by  FIG.  4   . At step  404 , the engine  112  is running and the transmission  114  is stopped as a result of the engagement of the brake  102  via actuation of the caliper  202 . The caliper  202  can be actuated by introduction of transmission oil from the hydraulic pump  116 , the accumulator  304 , or both at a pressure sufficient to actuate the caliper  202 . 
     A user or control system (e.g., an ESC) can then turn off or otherwise idle the engine  102 , as at step  406 .  FIG.  5 C  illustrates a schematic showing hydraulic control of the brake system illustrated in  FIG.  3    when the pump trailer is operating at step  406  of the method illustrated by  FIG.  4   . At step  406 , the brake  102  can be released, thereby placing the transmission  114  in neutral. 
     A user or control system (e.g., the ESC) can then reapply or reset the brake  102  to place the transmission  114  in a stationary mode. While the transmission  114  is in a stationary mode, the shaft  104  and pump  110 , each mechanically linked to the transmission  114 , can also be rendered stationary.  FIG.  5 D  illustrates a schematic showing hydraulic control of the brake system illustrated in  FIG.  3    when the pump trailer is operating at step  408  of the method illustrated by  FIG.  4   . At step  408 , the brake  102  is set at a force sufficient to prevent rotation of the transmission  114  and the shaft  104  so that both transmission  114  and the shaft  104  are stationary. At step  408 , the engine  112  can remain in an off position. For example, the engine  112  can be shut off or otherwise rendered stationary by virtue of being in a standby mode induced by the ESC. Standby mode can include a state in which the engine  112  is turned off and comes to a standstill, between two successive production phases in which the pumps operate under high pressure and press material into a borehole, particularly between two test phases or between a test phase and a production phase. 
     When the engine  112  is placed in a standby mode or is otherwise shut off, the pressurized transmission oil in the accumulator  304  can be utilized as needed to achieve a transmission oil pressure sufficient to actuate the brake caliper  202  upon input of a brake signal, thereby placing the transmission  114  in a stationary mode when the engine  112  is off or idle. The setting of the brake  102  can place the transmission  114 , the shaft  104 , and the pump  110  in a stationary mode in anticipation of restarting the engine  112 , either manually or with assistance from the ESC. By placing the transmission  114  in a stationary mode prior to restarting the engine  112 , damage from the restart can be avoided since the shaft  104  and pump  110  mechanically linked or otherwise coupled to the transmission  114  would be prevented from unwanted forces experienced by the restarting of the engine  112 . 
     A user or control system can then turn the engine  112  and the mainswitch off so that the accumulator  304  can be drained, as at  410 .  FIG.  5 E  illustrates a schematic showing hydraulic control of the brake system illustrated in  FIG.  3    when the pump trailer is operating at step  410  of the method illustrated by  FIG.  4   . At step  410 , the accumulator  304  and safety block  302  can be drained of transmission oil contained therein and in the flow lines coupled to or fluidically linked to accumulator  304  and safety block  302 , thereby enabling maintenance or removal of any portion of the brake system  300 . The transmission oil can be drained from the accumulator  304  and safety block  302  by opening the two-way solenoid valve  318  to allow the transmission oil to pass therethrough and ultimately into the reservoir  208 . The accumulator  304  and safety block  302  can also be drained of the transmission oil by opening the second valve  314  to allow the transmission oil to pass therethrough and ultimately into the reservoir  208 . A user or control system can then turn the pump trailer  100  and its engine  112  back on, for example, via a cold start, to return to the mode of operation illustrated by  FIG.  5 A . 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description and the appended claims, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term “and/or” as used herein refers to and encompasses any and possible combinations of one or more of the associated listed items. It will be further understood that the terms “includes,” “including,” “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, operations, elements, components, and/or groups thereof. Further, as used herein, the term “if” may be construed to mean “when” or “upon” or “in response to determining” or “in response to detecting,” depending on the context. 
     As used herein, the terms “inner” and “outer”; “up” and “down”; “upper” and “lower”; “upward” and “downward”; “above” and “below”; “inward” and “outward”; and other like terms as used herein refer to relative positions to one another and are not intended to denote a particular direction or spatial orientation. The terms “couple,” “coupled,” “connect,” “connection,” “connected,” “in connection with,” and “connecting” refer to “in direct connection with” or “in connection with via one or more intermediate elements or members.” 
     It will also be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first object could be termed a second object, and, similarly, a second object could be termed a first object, without departing from the scope of the present disclosure.