The present disclosure provides a method comprising determining an ore map for a heap to identify a location of a recoverable metal-bearing material in the heap, wherein the metal-bearing material comprises iron and at least one other metal value, delivering a leaching solution from a leaching solution source to a leaching solution regulating system, wherein the leaching solution comprises an effective amount of citric acid and hydrogen peroxide, regulating at least one of a pressure, a mass flow rate, or a volumetric flow rate of the leaching solution to achieve a target operational condition, wherein the target operational condition is selected to optimize a set of operational parameters to maximize recovery of the at least one other metal value, delivering the leaching solution at the target operational condition from the leaching solution regulating system to the subsurface leaching distribution system, and delivering the leaching solution at the target operational condition from the subsurface leaching distribution system to the location of the recoverable metal-bearing material under a surface of the heap to leach and recover the at least one other metal value.

The present disclosure provides a method comprising determining an ore map for a heap to identify a location of a recoverable metal value in the heap, delivering a leaching solution from a leaching solution source to a leaching solution regulating system, regulating at least one of a pressure, a mass flow rate, or a volumetric flow rate of the leaching solution to achieve a first target operational condition, wherein the first target operational condition is selected to optimize a set of operational parameters to maximize recovery of the recoverable metal value, delivering the leaching solution at the first target operational condition from the leaching solution regulating system to a subsurface leaching distribution system, and delivering the leaching solution at the first target operational condition from the subsurface leaching distribution system to the location of the recoverable metal value under a surface of the heap to leach and recover at least one metal value.

An electromagnetic pressure control valve, comprising: an electromagnetic actuator configured to position a piston that is received axially movable in a receiving opening of a controller housing, wherein the piston facilitates opening or closing flow connections of the electromagnetic pressure control valve, wherein the piston includes a pin at a face that is oriented away from the electromagnetic actuator, wherein a relative movement is enabled between the pin and the piston, wherein a surface of the pin that is arranged in the controller housing and oriented away from the piston is arranged opposite to a stop, wherein the pin is spring loaded to contact the stop so that a movement of the pin in a direction towards the stop is prevented, and wherein a preload element that is configured to provide the spring loading engages the pin.

A pressure regulating valve includes a housing, control slide valve, coupling rod, armature, outlet port, and pressure transmission pin. The armature demarcates a first fluid space and a second fluid space from each other. The rod extends with a constant first outer cross-sectional shape in a direction of a longitudinal axis, and at least partially demarcates a third fluid space that fluidically connects the first fluid space to the outlet port. The pin extends with a constant second outer cross-sectional shape in the direction of the longitudinal axis, and at least partially delimits the third fluid space. The pin is positioned so that one end facing toward the armature projects into the control slide valve, and another end facing away from the armature is at least indirectly supported against the housing. A hydraulically effective area of the second shape is larger than a hydraulically effective area of the first shape.

A counter pressure valve arrangement for controlling a pressure level of a hydraulic fluid in a return line from a hydraulic actuator arrangement. The counter pressure valve arrangement comprises a counter pressure valve having: a moveable valve member; a counter pressure regulating port configured for being connected to the hydraulic actuator arrangement via the return line; a tank port configured for being connected to a tank or low pressure reservoir for storing low pressure hydraulic fluid; and a pump port configured for being connected to a source of pressurised hydraulic fluid. A first position of the valve member effects fluid communication between the pump port and the counter pressure regulating port for supplying pressurised hydraulic fluid to the return line (4), and a second position of the valve member effects fluid communication between the counter pressure regulating port and the tank port for discharging hydraulic fluid from the return line to the tank.

A valve assembly includes a proportional valve having an opening cross section that can be continuously varied by an actuator; a sensor for sensing the valve output pressure; a digital regulating device; and a switching valve disposed parallel to the proportional valve. The opening cross section of the switching valve is smaller than the maximum opening cross section of the proportional valve. The regulating device is programmed (i) to automatically calculate, at runtime, using the currently given valve output pressure and the current position of the actuator, the maximum working pressure achievable at the maximum opening of the proportional valve with the valve, (ii) and to additionally open the switching valve when the computed maximum achievable working pressure falls below a predefinable target working pressure by a definable deviation value.

A counter pressure valve arrangement for controlling a pressure level of a hydraulic fluid in a return line from a hydraulic actuator arrangement. The counter pressure valve arrangement comprises a counter pressure valve having: a moveable valve member; a counter pressure regulating port configured for being connected to the hydraulic actuator arrangement via the return line; a tank port configured for being connected to a tank or low pressure reservoir for storing low pressure hydraulic fluid; and a pump port configured for being connected to a source of pressurised hydraulic fluid. A first position of the valve member effects fluid communication between the pump port and the counter pressure regulating port for supplying pressurised hydraulic fluid to the return line, and a second position of the valve member effects fluid communication between the counter pressure regulating port and the tank port for discharging hydraulic fluid from the return line to the tank.

An electromagnetic pressure reducing valve includes a spool valve configured to allow or shut off communication between a pilot passage and a pilot pressure supply passage and a solenoid configured to give a thrust according to an intensity of a supplied electric current to the spool valve. The spool valve has a pressure receiving surface configured to generate a thrust in a direction opposite to the thrust by the solenoid by action of a pressure of a pilot pressure supply passage, and an area of the pressure receiving surface is set smaller than a cross sectional area of the spool valve.

The factory installed pressure regulator valve of an automotive transmission is replaced by a pressure regulator valve having two separate valve components conjointly movable together in a bore. A protrusion or protuberance extending from the center of one end of one of the valve components defines a fulcrum which abuts against an adjacent end of the other valve component as the two valve components move conjointly and in direct contact with each other within the bore during operation of the pressure regulator valve. Preferably, an opening is provided in a land in one of the valve components to vent hydraulic fluid (transmission oil) to prevent a pressure build-up in the bore which might separate the two valve components from each other during reciprocating movement of the valve components in the bore.

Valve with in-built pressure threshold detection, mounted in an engine block pipe, the valve comprising a body comprising an electrically insulating external element (16) and an electrically conducting internal element (18) bearing the obturator seat (14), an obturator (12), the valve also comprising an electrical terminal (34) connected to a detection system which, with the engine block (4) and the internal element (18), forms an electric circuit, the internal element (18) being in permanent contact with the electrical terminal (34), the internal element (18) sliding in the external element (16) such that, for a pressure below the threshold pressure, the internal element (18) is in electrical contact with the engine block, closing the electric circuit, and for a pressure equal to or greater than the threshold pressure, the internal element (18) is not in electrical contact with the engine block, breaking the electric circuit.