A UAV propulsion system is disclosed that utilizes a crankcase having a first crankcase compartment and a second crankcase compartment. Each crankcase compartment includes a corresponding cylinder assembly and piston, with each piston being interconnected with a rotatable crankshaft. A first airflow path extends from an exterior of the UAV propulsion system to the first crankcase compartment, and a separate second airflow path extends from the exterior of the UAV propulsion system to the second crankcase compartment. A first rotary valve may be mounted on and rotate with the crankshaft to control the airflow along the first airflow path to the first crankcase compartment, while a second rotary valve may be mounted on and rotate with the crankshaft to control the airflow along the second airflow path to the second crankcase compartment.

A housing for a motor or compressor has an elongate crankcase with two end surfaces. At least one cylinder chamber is provided in which a piston is caused to perform a movement by rotation of the crankshaft. The internal diameter of the crankcase narrows monotonously from the first end surface to the second end surface. A crankcase shaped in this way can be manufactured particularly easily by virtue of the casting being performed around a shaping mandrel. A shaping mandrel of this type must likewise narrow monotonously in order that, after the casting has been performed around it, the shaping mandrel can be pulled out of the housing at a first end. By way of the shaping of the crankcase, it is possible for the housing to be of unipartite and at the same time very compact construction.

A compressor and a refrigeration system having the same are provided. The compressor includes a crankcase, a thrust bearing and a crankshaft. The crankcase is formed with a crankshaft hole therein and provided with a mounting protrusion at an upper end thereof. The crankshaft hole runs upward through the mounting protrusion. The thrust bearing is fitted over the mounting protrusion. The crankshaft is rotatably disposed within the crankshaft hole, has a thrust part, and is formed with an oil supply passage therein. A lower end face of the thrust part is abutted against an upper end face of the thrust bearing. A cavity is defined by the mounting protrusion, the thrust bearing and the thrust part. A through hole is formed in a peripheral wall of the crankshaft for communicating the oil supply passage with the cavity.

A balance weight includes a main weight portion extending over a range defined by a circular-arc circumferential edge centered at a rotational shaft hole side and a pair of virtual end surfaces located on the circular-arc circumferential edge on both sides of the rotational shaft hole, a pair of extension weight portions extending from the pair of virtual end surfaces to an opposite circular-arc side of the rotational shaft hole from the circular-arc circumferential edge, the rotational shaft hole provided at the main weight portion so as to be located on a central side of the circular-arc circumferential edge, a crank shaft attachment protrusion, a crank shaft hole provided at the crank shaft attachment protrusion radially eccentrically with respect to the rotational shaft hole, and a pair of spaces formed between positions on both sides of the crank shaft attachment protrusion and the pair of extension weight portions, respectively.

A crankcase assembly for a reciprocating machine is provided in which a crankcase having at least one cylinder with a wet cylinder liner arranged therein. A cylinder head for charging and discharging pressurized gas is mounted on the crankcase and a cylinder head gasket for preventing leakage of pressurized gas out of the cylinder is arranged between the crankcase and the cylinder head and is running circumferentially spaced from the inner wall of the cylinder liner. A circumferential coolant channel is formed between the inner crankcase wall and an outer wall of the cylinder liner, wherein a lower sealing means is arranged between the inner crankcase wall and the cylinder liner on the crankshaft side of the coolant channel for preventing leakage of coolant fluid. An upper sealing means is arranged between the inner crankcase wall and the cylinder liner on the cylinder head side of the coolant channel for preventing leakage of coolant fluid.

A system that can eliminate engine combustion emissions in addition to raw and fugitive methane emissions associated with a gas compressor package. The system may comprise an air system for starting and instrumentation air supply; electrically operated engine pre/post-lube pump, compressor pre-lube pump, and cooler louver actuators; compressor distance piece and pressure packing recovery system; blow-down recovery system; engine crankcase vent recovery system; a methane leak detection system; and an overall remote monitoring system.

Disclosed is an air compressor (10) for supplying compressed air to a pneumatic system in a motor vehicle. The air compressor (10) comprises a crankcase (46), a cylinder housing (14) connected to the crankcase, a cylinder head (20), a crankshaft (40) rotatably mounted in the crankcase, a cylindrical piston (12) that is connected to the crankshaft (40) by a connecting rod (42). In order to load the compressed air with as little heat as possible, the crankcase (46), the cylinder housing (14), the cylinder head (20), and the piston (12) are made of aluminum or an aluminum alloy, and the at least one piston ring (54) or the at least one oil ring is made of gray cast iron or polytetrafluoroethylene (PTFE).

A 3D-printed oil separation assembly for use in a reciprocating compressor is provided. The compressor includes a suction chamber, a crankcase chamber, and at least one partition member at least partially separating the suction chamber and the crankcase chamber. The at least one partition member further includes at least one opening. The 3D-printed oil separation assembly comprises a coalescing structure positioned within the crankcase chamber adjacent the at least one partition member at the at least one opening; and at least one securing structure secured in operable relation with the at least one demisting structure so as to secure the coalescing structure relative to the opening. The coalescing structure comprises at least one structure selected from the group consisting of a baffled structure, a demisting structure, and combinations thereof. At least a portion of the coalescing structure is 3D-printed.

A skid for supporting a reciprocating pump assembly, the reciprocating pump assembly including a power end frame assembly having a pair of end plate segments and a plurality of middle plate segments disposed between the end plate segments. The end plate segments each have at least a pair of feet and the middle plate segments each having at least one foot. The skid includes a base and a plurality of pads extending from the base. At least a portion of the plurality of pads correspond to the end plate segment feet and at least another portion of the plurality of pads correspond to the at least one foot of each middle plate segment.

A system that can eliminate engine combustion emissions in addition to raw and fugitive methane emissions associated with a gas compressor package. The system may comprise an air system for starting and instrumentation air supply; electrically operated engine pre/post-lube pump, compressor pre-lube pump, and cooler louver actuators; compressor distance piece and pressure packing recovery system; blow-down recovery system; engine crankcase vent recovery system; a methane leak detection system; and an overall remote monitoring system.