Abstract: Systems, methods, and apparatus, including computer programs encoded on computer-readable media, for generating pressure signals in a wellbore of a well system. A target amplitude may be determined for a target pressure signal to be generated in the wellbore of the well system. A rate drop step size may be determined for each rate drop of a plurality of rate drops. During fracturing operations in the well system, the plurality of rate drops may be performed in sequence for a system operational rate to generate the target pressure signal. Each rate drop of the plurality of rate drops may have the rate drop step size. One or more fracturing operation metrics may be determined for the well system from the target pressure signal.

Abstract: Techniques for determining subsurface conditions in a multi-well system may include detecting, at time t1, a tube wave at a first well system of the multi-well system. The techniques may further include detecting, at time t2, the tube wave at a second well system of the multi-well system. The techniques may further include determining a time differential td between t1 and t2. The techniques may further include determining, based at least in part on td, that the first well system and the second well system are in fluid communication via a formation.

Abstract: A method for controlling changes in pump flow rates. The method involves identifying a first plurality of pumps scheduled to go offline and calculating a corresponding total flow decrease rate. Additionally, a second plurality of pumps intended to go online is identified, and a total flow increase rate is calculated based on these pumps. A determination is then made as to whether the difference between the total flow decrease rate and the total flow increase rate exceeds a predetermined flow rate threshold. If the threshold is exceeded, pump throttling is implemented based on this determination to manage the change in flow rates.

Abstract: Systems, methods, and apparatus, including computer programs encoded on computer-readable media, for generating pressure signals in a wellbore of a well system. A target amplitude may be determined for a target pressure signal to be generated in the wellbore of the well system. A rate drop step size may be determined for each rate drop of a plurality of rate drops. During fracturing operations in the well system, the plurality of rate drops may be performed in sequence for a system operational rate to generate the target pressure signal. Each rate drop of the plurality of rate drops may have the rate drop step size. One or more fracturing operation metrics may be determined for the well system from the target pressure signal.

Abstract: A method for determining a new factor vector for a first hydraulic fracture treatment in a wellbore. The method may include determining, based on one or more first pressure pulses, a first current resistance in the well during the first hydraulic fracture treatment; determining a second factor vector based, at least in part, on a first factor vector and the first current resistance and a target resistance; implementing the second factor vector in the wellbore; determining, based on one or more second pressure pulses, a second current resistance in the well during the first hydraulic fracture treatment; determining whether the second current resistance is above a resistance threshold; and in response to the second current resistance being above the resistance threshold, determining a third factor vector.

Abstract: Techniques for determining subsurface conditions in a multi-well system may include detecting, at time t1, a tube wave at a first well system of the multi-well system. The techniques may further include detecting, at time t2, the tube wave at a second well system of the multi-well system. The techniques may further include determining a time differential td between t1 and t2. The techniques may further include determining, based at least in part on td, that the first well system and the second well system are in fluid communication via a formation.

Abstract: A method for evaluating one or more properties of a wellbore. The method may include identifying a total power from all electric pump motors being used in a fracture operation, gradually reduce pump rates for one or more of the electric pump motors except for one or more selected electric pump motors. The method may further include gradually reduce the pump rate of the selected pump motors and stabilizing the pressure by holding the selected pump motors at a constant rate.

Abstract: A method comprises inducing, via one or more hydraulic fracturing components, a first signal in hydraulic fracturing fluid in a treatment well while hydraulically fracturing the treatment well, wherein the treatment well is formed in a subsurface formation. The method comprises detecting, via one or more sensors, a response signal in one or more offset wells formed in the subsurface formation based on the first signal, wherein the response signal indicates well connectivity between the treatment well and the one or more offset wells.

Abstract: An electrochemical device having a roll with elongated electrodes each supported in one of two alternating folds of a separator layer, and spirally wound in the roll with the separator layer to define two opposing ends, each of such ends only exposing a different one of the electrodes wound along the roll. The device having a disc shaped housing having upper and lower portions fixable to each other to set the device height. The upper portion provides a first member with a first surface disposed along one end of the roll. A second member with a second surface is disposed along the other end of the roll. Spring elements compressed between the second member and a third member, provided by the housing lower portion, apply pressure to force the second member toward the first member promoting contact of the first and second surfaces with different ones of the exposed electrodes.

Abstract: Disclosed is generating an acquisition request of a component, using a probabilistic model based on current and planned life consumption, to maintain a usable component inventory, by: determining planned consumption of the component; retrieving historical lifetime data associated with the component; determining the associated normalized current life consumed for historical specimens at failure based on a power law equivalency model; determining a probability of survival distribution associated with the component; determine a probability of future failure of each component in inventory given planned consumption of the component; determine a projected number of component failures prior to completion of the job associated with the component; generate the at least one acquisition request to acquire a quantity of new components at least equal to the projected number of specific component failures prior to completion of the job; wherein the usable inventory of the component includes at least the quantity of new com

Abstract: A method for controlling changes in pump flow rates that includes identifying a first plurality of pumps to go offline, calculating a total flow decrease rate based on the first plurality of pumps, identifying a second plurality of pumps to go online, calculating a total flow increase rate based on the second plurality of pumps, making a determination that a difference between the total flow decrease rate and the total flow increase rate exceeds a flow rate threshold, and implementing pump throttling based on the determination.

Abstract: A method for controlling one or more frac pumps of a fracturing spread. The method comprises adjusting a total pump rate of one or more target pumps of the frac pumps to achieve a total rate setpoint for the frac pumps. The method comprises activating one or more trim pumps for an additional pump rate to compensate for a total rate dip occurring when the total pump rate of the one or more target pumps is adjusted.

Abstract: Disclosed is generating an acquisition request of a component, using a probabilistic model based on current and planned life consumption, to maintain a usable component inventory, by: determining planned consumption of the component; retrieving historical lifetime data associated with the component; determining the associated normalized current life consumed for historical specimens at failure based on a power law equivalency model; determining a probability of survival distribution associated with the component; determine a probability of future failure of each component in inventory given planned consumption of the component; determine a projected number of component failures prior to completion of the job associated with the component; generate the at least one acquisition request to acquire a quantity of new components at least equal to the projected number of specific component failures prior to completion of the job; wherein the usable inventory of the component includes at least the quantity of new com

Abstract: An electrochemical device having a roll with elongated electrodes each supported in one of two alternating folds of a separator layer, and spirally wound in the roll with the separator layer to define two opposing ends, each of such ends only exposing a different one of the electrodes wound along the roll. The device having a disc shaped housing having upper and lower portions fixable to each other to set the device height. The upper portion provides a first member with a first surface disposed along one end of the roll. A second member with a second surface is disposed along the other end of the roll. Spring elements compressed between the second member and a third member, provided by the housing lower portion, apply pressure to force the second member toward the first member promoting contact of the first and second surfaces with different ones of the exposed electrodes.

Abstract: Rechargeable battery modules and rechargeable battery module handling methods are described. According to one aspect, a rechargeable battery module includes a housing, a plurality of terminals, a plurality of rechargeable cells within the housing and coupled with the terminals, and wherein the rechargeable cells are configured to store electrical energy, a plurality of lift members at different locations of the housing, and wherein the lift members provide a plurality of lift points for the rechargeable battery module which enable the rechargeable battery module to be lifted in a plurality of different orientations.

Abstract: Rechargeable battery modules and rechargeable battery module handling methods are described. According to one aspect, a rechargeable battery module includes a housing, a plurality of terminals, a plurality of rechargeable cells within the housing and coupled with the terminals, and wherein the rechargeable cells are configured to store electrical energy, a plurality of lift members at different locations of the housing, and wherein the lift members provide a plurality of lift points for the rechargeable battery module which enable the rechargeable battery module to be lifted in a plurality of different orientations.

Abstract: Methods, apparatus, and computer program products are disclosed for determining a reported state of charge (“SOC”) of a battery system, the methods, apparatus, and computer program products including determining the reported SOC according to a first determining method when a previous SOC is greater than a first SOC threshold percentage and less than or equal to 100%; determining the reported SOC according to a second determining method when the previous SOC is greater than a second threshold percentage and less than or equal to the first SOC threshold percentage; and determining the reported SOC according to a third determining method when the previous SOC is greater than or equal to 0% and less than or equal to the second SOC threshold percentage.

Abstract: This disclosure includes battery systems and operational methods. According to one aspect, a battery system includes conversion circuitry, a plurality of main terminals configured to be coupled with a load, a charger and a plurality of rechargeable battery modules which are coupled in series with one another intermediate the main terminals, switching circuitry configured to couple a first of the battery modules with an input of the conversion circuitry, and the conversion circuitry being configured to modify an electrical characteristic of electrical energy received from the first of the battery modules and to output the electrical energy having the modified characteristic to a second of the battery modules.

Abstract: This disclosure includes battery systems and operational methods. According to one aspect, a battery system includes conversion circuitry, a plurality of main terminals configured to be coupled with a load, a charger and a plurality of rechargeable battery modules which are coupled in series with one another intermediate the main terminals, switching circuitry configured to couple a first of the battery modules with an input of the conversion circuitry, and the conversion circuitry being configured to modify an electrical characteristic of electrical energy received from the first of the battery modules and to output the electrical energy having the modified characteristic to a second of the battery modules.