A valve for controlling a molten liquid includes an expansion port in liquid communication with an internal volume of the valve that is filled with the molten liquid. An expansion valve can be opened during unfreezing of the valve, to allow melting process substance to expand out of the internal volume into an expansion line as it is melted. During initialization of the valve, an inert gas source, pressure regulator, and ultrasonic transition level sensor can be used to establish a liquid/gas interface at a desired height within the expansion line. The valve can include a multi-zone heater, wherein a first of the zones is adjacent the expansion port, so that during unfreezing, after the first zone has been melted, the remaining zones can be sequentially activated in an order that ensures that each zone is activated only after an adjacent zone has been melted.

A valve for controlling a molten liquid includes an expansion port in liquid communication with an internal volume of the valve that is filled with the molten liquid. An expansion valve can be opened during unfreezing of the valve, to allow melting process substance to expand out of the internal volume into an expansion line as it is melted. During initialization of the valve, an inert gas source, pressure regulator, and ultrasonic transition level sensor can be used to establish a liquid/gas interface at a desired height within the expansion line. The valve can include a multi-zone heater, wherein a first of the zones is adjacent the expansion port, so that during unfreezing, after the first zone has been melted, the remaining zones can be sequentially activated in an order that ensures that each zone is activated only after an adjacent zone has been melted.

A valve assembly for a turbine engine includes a valve arranged in an air flow path. The valve has a shaft. The valve is movable between an open position and a closed position. An electric actuator is coupled to the shaft and is configured to move the valve between the open position and the closed position. A thermal barrier is arranged between the valve and the electric actuator.

Heat tracing systems and related methods are disclosed. An example valve includes a valve body defining a fluid flow passageway between a primary inlet and a primary outlet. The body valve has a first face adjacent the main inlet, the first face including a first groove. A first cover is positioned over the first groove to define a first heat tracing path. A secondary inlet is formed in the valve body and fluidly coupled to the first heat tracing path. A secondary outlet formed in the valve body and fluidly coupled to the first heat tracing path.

A heated water valve provides electrical resistance heaters placed within flange connections of the valve to provide for an integrated heater valve assembly with good heat conduction and spreading capabilities that can prevent water valve freezing at low temperatures.

A heat exchanger is configured to adjust a flow restriction of flow passages through the heat exchanger in response to changes in temperature of elements that define at least a portion of the flow passages. The elements include a first material having a first coefficient of thermal expansion, and a second material having a second coefficient of thermal expansion that is different from the first coefficient of thermal expansion.

A heat exchanger is configured to adjust a flow restriction of flow passages through the heat exchanger in response to changes in temperature of elements that define at least a portion of the flow passages. The elements include a first material having a first coefficient of thermal expansion, and a second material having a second coefficient of thermal expansion that is different from the first coefficient of thermal expansion.

A high-pressure self-sealing butterfly valve, which comprises a valve body and a valve shaft, wherein a flow channel and a butterfly plate are arranged in the valve body, a pure metal sealing ring and a pure metal valve seat are sequentially arranged at a portion, on the outer side of the butterfly plate, of the flow channel, a piston cavity is further formed in a flow direction end face of the pure metal valve seat, and an upper valve shaft and a lower valve shaft are arranged at the upper end and the lower end of the valve shaft respectively; an upper end cover assembly and an upper self-sealing assembly are arranged between the end part of the upper valve shaft and the valve body, a lower sealing bottom cover and a lower self-sealing assembly are arranged between the end part of the lower valve shaft and the valve body.

A vacuum valve includes a valve plate that covers an exhaust port of a vacuum chamber, and a poppet type actuator that drives the valve plate in an axial direction orthogonal to a surface of the vacuum chamber on which the exhaust port is provided. The actuator includes a shaft that is connected to the valve plate, a drive unit that is disposed side by side with the shaft in a radial direction of the shaft and includes a ball screw shaft and a drive source that rotates the ball screw shaft, and a connection part that connects the ball screw shaft and the shaft and moves in the axial direction together with the shaft to a position where the valve plate covers the exhaust port.

A valve includes a body with an inlet at a first end of the body, and an outlet at a second end of the body. A first electrically resistive heating element is located in the inlet and heats a first fluid source to a temperature above 0 degrees C. A second electrically resistive heating element is located in the outlet and heats a second fluid source to a temperature above 0 degrees C.