An object of the present invention is to provide a fluid control device with an improved effect of suppressing blowhole generation. Therefore, a component for a flow rate control device of the present invention includes: a first component 140 (A); a second component 107 (B) fixed to the first component by a press-fitting portion 802; a butt-welded portion 803 connecting the first component and the second component; and a first gap 1001 and a second gap 1002 formed between mutually opposing surfaces of the first component and the second component. The first gap is provided on a side of the press-fitting portion with respect to the second gap between the press-fitting portion and the butt-welded portion, and is formed in a direction intersecting a press-fitting direction. The second gap is provided on a side of the butt-welded portion with respect to the first gap between the press-fitting portion and the welded portion, and is formed in a direction intersecting the first gap.

A fuel supply valve for a slurry fuel injector valve, the fuel supply valve comprising: a fuel inlet for fluid communication with a slurry fuel reservoir; a fuel outlet for fluid communication with a nozzle of the fuel injector valve; a pump chamber port for fluid communication with a pump chamber of the fuel injector valve; and a valve gate moveable between a first position, at which the fuel inlet is in fluid communication along a first slurry fuel flow path with the pump chamber port, and a second position, at which the fuel outlet is in fluid communication along a second slurry fuel flow path with the pump chamber port; wherein the valve gate is operable with a valve actuation liquid from an engine.

Disclosed is a slurry fuel injector valve, comprising: a fuel outlet valve through which slurry fuel is able to exit the slurry fuel injector valve towards a combustion chamber of an engine; a pump cavity; a pump element that divides the pump cavity into a pump chamber and an actuation chamber; a fuel conduit through which slurry fuel is flowable from the pump chamber to the fuel outlet valve; and an actuation fluid conduit through which actuation fluid is flowable from the actuation chamber to the fuel outlet valve.

A spray nozzle comprising: a body comprising a duct, a seat arranged at the first end, and including an opening forming an inlet, a guide comprising a tubular jacket and a retaining member, the retaining member retaining the jacket in the duct, a plug mounted to slide axially in the channel of the jacket, the plug being pushed back against the opening by a spring, and in abutment against the bottom of the jacket, the guide comprising a radial vent, which comprises a vent channel isolated from the flow of fluid and connecting the inside of the guide jacket to a bore formed in the body of the spray nozzle.

When a pressure of fuel is intensified using a pressure intensifier, an electronic control unit is configured to set a target common rail pressure to be higher as a fuel leakage volume that is a volume of fuel leaking from a common rail to a fuel tank becomes larger until a three-way valve is switched from a state in which the pressure intensifier is connected to the common rail to a state in which the pressure intensifier is connected to the fuel tank.

An insert for use with a fuel injector comprises a shaft including a substantially cylindrical configuration defining a shaft cylindrical axis, a shaft radial direction, and a shaft diameter; and a head including a substantially cylindrical configuration defining a head cylindrical axis, a head radial direction, and a head diameter. The shaft and head may be attached to each other, the shaft cylindrical axis and the head cylindrical axis may be parallel to each other, the head diameter may be greater than the shaft diameter, and the shaft cylindrical axis may be spaced away from the head cylindrical axis.

An insert for use with a fuel injector comprises a shaft including a substantially cylindrical configuration defining a shaft cylindrical axis, a shaft radial direction, and a shaft diameter; and a head including a substantially cylindrical configuration defining a head cylindrical axis, a head radial direction, and a head diameter. The shaft and head may be attached to each other, the shaft cylindrical axis and the head cylindrical axis may be parallel to each other, the head diameter may be greater than the shaft diameter, and the shaft cylindrical axis may be spaced away from the head cylindrical axis.

A fuel supply valve for a slurry fuel injector valve, the fuel supply valve comprising: a fuel inlet for fluid communication with a slurry fuel reservoir; a fuel outlet for fluid communication with a nozzle of the fuel injector valve; a pump chamber port for fluid communication with a pump chamber of the fuel injector valve; and a valve gate moveable between a first position, at which the fuel inlet is in fluid communication along a first slurry fuel flow path with the pump chamber port, and a second position, at which the fuel outlet is in fluid communication along a second slurry fuel flow path with the pump chamber port; wherein the valve gate is operable with a valve actuation liquid from an engine.

Disclosed is a slurry fuel injector valve, comprising: a fuel outlet valve through which slurry fuel is able to exit the slurry fuel injector valve towards a combustion chamber of an engine; a pump cavity; a pump element that divides the pump cavity into a pump chamber and an actuation chamber; a fuel conduit through which slurry fuel is flowable from the pump chamber to the fuel outlet valve; and an actuation fluid conduit through which actuation fluid is flowable from the actuation chamber to the fuel outlet valve.

Disclosed is a valve needle for a needle valve of a slurry fuel injector valve, the valve needle comprising: a tip for abutting a needle valve seat of the needle valve; a sealing portion for location in a bore of the needle valve; and a fuel chamber portion between the tip and the sealing portion, wherein the fuel chamber portion is for location in a needle fuel chamber of the needle valve; wherein a surface of the sealing portion of the valve needle comprises at least one groove and wherein at least part of the or each groove extends in a direction that is non-perpendicular to an axial direction of the valve needle.