A pilot actuated valve assembly includes a valve body having an inlet and an outlet, and includes a main valve, a pilot valve, and a pilot cavity which is at a pilot cavity pressure. A tube houses parts of the pilot valve, and a sleeve engages a portion of the tube, with both being secured to the body by a valve bonnet. The main and pilot valves are coaxial. A solenoid actuator or other suitable actuator is operatively coupled to a shaft of the pilot valve and shifts the pilot valve between the positions. Consequently, the main valve shifts between the closed and open positions in response to shifting of the pilot valve between the closed and open positions.

Disclosed herein are a fuel supply system for ships and a fuel supply method using the same. The fuel supply method includes: 1) supplying an excess amount of liquefied gas as fuel to an incompressible fluid-fueled engine (E); 2) cooling unconsumed fuel discharged from the engine (E) through heat exchange with liquefied gas discharged from a storage tank (T); 3) returning the unconsumed fuel discharged from the engine (E) and having been cooled through heat exchange in step 2) to the storage tank (T); and 4) supplying the liquefied gas discharged from the storage tank (T) and having been used as refrigerant for heat exchange in step 2) to the engine (E). The fuel supply method can prevent cavitation in the engine (E) by supplying the excess amount of liquefied gas sufficient to accommodate variation in load of the engine (E) as fuel to the engine (E).

The present invention provides a fuel pump capable of suppressing sticking of a plunger. The fuel pump of the present invention includes a plunger 2 that reciprocates, a cylinder 6 in which a guide hole 6a that guides the reciprocating motion of the plunger 2 extends in the axial direction, and a pump body 1 that holds the cylinder 6. The pump body 1 includes a cylinder insertion hole 1g into which the cylinder 6 is inserted, and a pressurizing chamber 11 that communicates with the cylinder insertion hole 1g and has a volume increased or decreased by the reciprocating motion of the plunger 2. The cylinder 6 includes a press-fitting portion 6b press-fitted into the inner peripheral surface of the cylinder insertion hole 1g, and a groove 6d formed at a position corresponding to the press-fitting portion 6b on the inner peripheral surface of the guide hole 6a.

The present invention relates to a method for controlling injection of a gaseous fuel, such as hydrogen or a hydrogen based gas, and a water-based fluid medium into a combustion engine. The method comprises the steps of: in a first operational mode injecting the gaseous fuel and optionally a water based fluid medium into a combustion chamber of the engine at a relatively high pressure; in a second operational mode injecting water as liquid into engine to reduce the temperature and pressure inside the combustion chamber, and injecting the gaseous fuel into the combustion chamber at a relatively low pressure.

In a gas engine provided with a gas supply pipe (35) branching into a supercharger-side gas supply pipe (33) and a cylinder-side gas supply pipe (37), a supercharger-side gas adjusting valve (43) and a cylinder-side gas adjusting valve (45) for controlling flow rates of passages, when the gas concentration of the fuel gas changes, the cylinder-side gas adjusting valve is controlled first to keep the output of the gas engine constant and then the supercharger-side gas adjusting valve is controlled to achieve the fuel gas flow rate Q1 based on the constant flow ratio by means of a gas supply controller (63), while maintaining the flow rate ratio Q1/Q2 at a constant value where Q1 is a fuel gas flow rate in the supercharger-side gas supply pipe and Q2 is a fuel gas flow rate in the cylinder-side gas supply pipe.

A pump includes a reservoir configured to receive a fluid pressurized by a boost pump. The pump also includes at least one pumping mechanism configured to receive a first flow of fluid from the reservoir and direct the first flow of fluid into a discharge passage of the pump without pumping the first flow of fluid when priming the pump. The at least one pumping mechanism is disposed in the reservoir such that the fluid in the reservoir surrounds at least a portion of the at least one pumping mechanism. The discharge passage is configured to output the first flow of fluid from the pump. The pump further includes a bypass passage configured to communicate a second flow of fluid from the reservoir to the storage tank.

A system for exchanging of different fuels that can be used for operation of an engine. The system includes a fuel exchange unit, a control and an exchange return conduit. The fuel exchange unit is configured to deliver a first fuel at pressure into the injections system given a switched-off engine, in order to replace a second fuel, which is located in the injection system, with the first fuel. A fuel delivery system includes a media converter which includes a deflectable element. The media converter is driven by a drive unit via the fluid by way of the fluid being able to be led at a varying pressure to the media transformer via a first feed conduit, and is configured to deliver the fuel via a pumping effect.

An internal combustion engine, a method of operating the internal combustion engine, and a controller are disclosed. The method may comprise measuring a first pressure at a first position in a fluid line containing pressurized fluid; comparing the first pressure to a first threshold; in response to the first pressure exceeding the first threshold, transmitting a signal to depressurize the fluid line; after transmitting the signal to depressurize the fluid line, measuring a second pressure in the fluid line and comparing the second pressure to at least one of a second threshold and a third threshold, the second threshold being greater than the third threshold and less than the first threshold; and in response to the second pressure being less than the second threshold and exceeding the third threshold, transmitting another signal to depressurize the fluid line.

An injector system which is in particular used as an injector block for fuel injection systems of mixture-compressing, spark-ignited internal combustion engines includes a fuel distribution rail, a counter bracket, a first injector, and at least one second injector. Here, the counter bracket has a first connecting piece and a second connecting piece. The first injector is joined to the counter bracket on an input side of the first connecting piece with the aid of an elastic sealing ring. The second injector is joined to the counter bracket on an input side of the second connecting piece with the aid of an elastic sealing ring. In this case, the counter bracket is connected to the fuel distribution rail. The fuel distribution rail is used for distributing compressed natural gas to the injectors. The injector system has a compact design.

In high horse power engines there are strict energy budgets allotted for each subsystem. It is a challenge for a gaseous fuel pumping system to supply the necessary gaseous fuel mass flow to the engine while staying within budget. A method for pressurizing a gaseous fuel supplied to an engine comprises providing first and second hydraulically actuated pumping apparatus comprising first and second shuttle valves in first and second hydraulic pistons respectively; and selectively communicating hydraulic fluid flow to the first and second hydraulically actuated pumping apparatuses. In a first mode hydraulic fluid is communicated through the first hydraulically actuated pumping apparatus to the second hydraulically actuated pumping apparatus. In a second mode hydraulic fluid is communicated through the second hydraulically actuated pumping apparatus to the first hydraulically actuated pumping apparatus. The method switches between the first and second modes when a pressure drop in hydraulic fluid pressure associated with the hydraulic fluid flowing through the first and second shuttle valves is detected.