A high integrity protection system includes a flow line including an inlet configured to be connected to a first source of pressure and an outlet configured to be connected to a downstream system. A first subsystem is installed on the flow line between the inlet and the outlet. A second subsystem is installed on the flow line between the inlet and the outlet, and the second subsystem is in a parallel flow configuration in relation to the first subsystem. The system includes a second source of pressure configured to be fluidically connected to the first subsystem and the second subsystem.

A valve device with pressure-reducing function, comprised of at least one logic valve (V1); one lock valve (V2); and one pressure-reducing valve (V3),
wherein the inlet (1) of the logic valve (V1) may be connected to a pressure supply source (HD), characterized in that the outlet (V1.2) of the logic valve (V1) and the outlet (V3.1) of the pressure reducing valve (V3) are connected together to an outlet or user port (A); and that the lock valve (V2) is connected with its inlet (V2.1) to the inlet (V1.1) of the logic valve (V1) as well as to a control side (V1.3) of the same, and with its outlet (V2.2) to an inlet (V3.2) of the pressure-reducing valve (V3).

The present disclosure relates to an intelligent positive and negative pressure system and an operation method therefor, and an intelligent positive and negative pressure electric appliance. The system comprises a positive and negative pressure intelligent fresh-keeping refrigerator, a positive and negative pressure intelligent washing machine, a positive and negative pressure dish washing and fruit and vegetable cleaning machine, a positive and negative pressure range hood, a positive and negative pressure baking and frying microwave oven, a positive and negative pressure fresh-keeping compartment container, a positive and negative pressure fresh-keeping warehouse, a positive and negative pressure disinfection machine, and a positive and negative pressure module cabinet. By means of the positive and negative pressure system, a fluid and a carried substance thereof are regulated and controlled by means of positive and negative pressure, so as to affect an object in a specific space in a targeted manner.

A redundant governor apparatus is provided for a vehicle air brake charging system. The apparatus comprises a first governor and a second governor. The apparatus also comprises a number of components arranged to enable (i) the first governor to act as primary and the second governor to act as backup to the first governor when the first governor is unable to act as primary, and (ii) the second governor to act as primary and the first governor to act as backup to the second governor when the second governor is unable to act as primary.

A packaging machine with an atmosphere modifying station in which an atmosphere within a packaging to be produced can be modified by evacuating air and/or introducing a gas. The packaging machine has a pressure control device that may control an evacuation pressure and/or a gassing pressure. The pressure control device may comprise a first controllable 2/2-way valve and a second controllable 2/2-way valve, both which are configured to influence the evacuation pressure and/or the gassing pressure by setting a volume flow. The first and second 2/2-way valves are connected in parallel with one another and are controllable independently of one another. In one embodiment, the first and second 2/2-way valves are preferably electrically controllable. A method of modifying an atmosphere within a package using a packaging machine and pressure control device is also provided.

A system is provided with a first valve having a first valve element, and a second valve having a second valve element, with the second valve positioned adjacent to the first valve. A first actuator is provided with an actuator member movable between a first actuator position and a second actuator position, and the actuator member is coupled to each of the first valve element and the second valve element for movement therewith. A method of controlling the system is also provided.

A pressure control system configured to automatically monitor and control pressure in fluid lines used in hydraulic fracturing or well stimulation activities is disclosed. The system generally includes at least two valve assemblies each having a valve and a valve actuation system, at least one pressure sensor, and an electro-mechanical control package. These components are configured such that the electro-mechanical controls automate the open and closed positions of the valve(s) via operation of the actuator(s) based on user inputs and information from the pressure sensor. This architecture allows the system to monitor and interpret pressures within the conduit and operate the valve position based on user defined signals and set-points. The valves may be positioned to redundantly monitor the same fluid conduit, or separate fluid conduits, and the system may be configured to enable independent valve positions based on independent user defined set-points or user inputted control signals.

An actuator system can include a first actuator, a second actuator, a first actuator control device configured to control the first actuator, a second actuator control device configured to control the second actuator, a shared redundant actuator control device, and at least one transfer device operatively connected to the first, second, and shared redundant actuator control devices. The at least one transfer device can be configured to be operated to select between a first control mode where the first actuator control device is operatively connected to the first actuator to control the first actuator and the second actuator control device is operatively connected to the second actuator to control the second actuator, a second control mode where the shared redundant actuator control device is operatively connected to the first actuator to control the first actuator and the second actuator control device is operatively connected to the second actuator to control the second actuator, and a third control mode where the first actuator control device is operatively connected to the first actuator to control the first actuator and the shared redundant actuator control device is operatively connected to the second actuator to control the second actuator.

An electro-hydraulic control system for actuating a control valve includes a control module. The control module is coupled to the surface via two hydraulic lines and an electric line. The control module uses one of the hydraulic lines as an open line and the other line as a close line. The control module includes a normally closed (NC) solenoid valve (SOV) that is coupled to the electric line and can be controlled from the surface to open or close. The opening or closing of the NC SOV in cooperation with hydraulic pressure on an open or close line of the hydraulic lines operates (i.e., closes or opens) the control valve.

A pressure control system may include a controller. A pressure control system may include a first sensor configured to determine a pressure of water flow through a first water inlet and transmit a signal to the controller indicative of the pressure of water flow through the first water inlet. A pressure control system may include a second sensor configured to determine a pressure of water flow through a second water inlet transmit a signal to the controller indicative of the pressure of water flow through the second water inlet. A pressure control system may include a valve in the second water inlet. The first water inlet may be an inlet from a water filtration system, and the second water inlet may be a water filtration bypass. The controller may be configured to open and close the valve based on received signals from the first sensor and/or the second sensor in order to maintain the pressure of water flow in the water supply system above a predetermined threshold.