A pig pumping unit is provided that allows eight passes to be made simultaneously with a single pumping unit. A single engine is used to drive three or four pumps, each connected into separate pumping units. Two engines may thus be used to drive up to eight pumps in a single trailer.

A pig pumping unit is provided that allows eight passes to be made simultaneously with a single pumping unit. A single engine is used to drive three or four pumps, each connected into separate pumping units. Two engines may thus be used to drive up to eight pumps in a single trailer.

A pig pumping unit is provided that allows eight passes to be made simultaneously with a single pumping unit. A single engine is used to drive three or four pumps, each connected into separate pumping units. Two engines may thus be used to drive up to eight pumps in a single trailer.

A unitized valve body for use in an automatic transmission includes a valve bore and an annulus. The valve bore is configured to receive a valve. The annulus is in fluid communication with the valve bore. The annulus defines an outer portion having an outer diameter and an innermost portion located at an interface between the valve bore and the valve. The outer portion having a first axial length and the innermost portion having a second axial length. The first axial length is greater than the second axial length.

A hydraulic unit includes a tank configured to be filled with a hydraulic fluid. The tank has at least one inflow connection and at least one outflow connection. A flow guide for the hydraulic fluid is formed between the inflow connection and the outflow connection. The flow guide is configured to have at least two 180° flow arcs configured to cool and calm the hydraulic fluid and to avoid dead zones.

A pneumatically controlled valve unit is specified, having a main valve for controlling a fluid flow of a fluid to be dosed. The valve unit has a piston shiftably mounted in a valve chamber, operating against a return device, and connected to a valve closing body of the main valve to open and close the main valve. The piston delimits a pressure chamber within the valve chamber such that the piston can be shifted against the return device by pressurizing the pressure chamber, wherein a position sensor is provided which is set up to detect the position of the piston in the valve chamber. One respective pressure line leads from the pressure chamber to a pressure fluid port and a ventilation port, wherein an aeration valve is arranged in one pressure line and a ventilation valve is arranged in the further pressure line, and wherein a control unit is provided which is set up to switch the aeration valve and the ventilation valve on the basis of the position of the piston detected by the position sensor to regulate a pressure in the pressure chamber for shifting the piston. Furthermore, a valve system comprising at least one valve unit, and a method of operating the valve unit are specified.

A piston-type water hammer absorber comprising: a cylinder body, a plug assembly and a piston; wherein a receiving cavity is formed in the cylinder body, and the piston is movably blocked in the receiving cavity; one end of the cylinder body is provided with a first opening and the other end is provided with a second opening, the first opening and the second opening respectively communicate with two ends of the receiving cavity, and an end of the cylinder body corresponding to the first opening is provided with a limiting part; and the plug assembly blocks the second opening, and a sealed cavity is formed between the plug assembly and the piston.

A hydraulic energy handling system for a working machine includes a high-pressure side; a low-pressure side; a hydraulic machine for mechanically driving, and being mechanically driven by, a mechanical driveline of the working machine; at least one high-pressure hydraulic energy storage connected to the high-pressure side; a hydraulic motor; a hydraulic pump arranged to supply hydraulic fluid to an inlet side of the hydraulic motor; and a return line for conducting hydraulic fluid to a hydraulic tank. The system further includes a pressure relief valve between the high-pressure side and the return line and arranged to discharge excess hydraulic energy from the high-pressure side to the return line to provide a braking force on the mechanical driveline; and a priority valve arrangement connected to an outlet side of the hydraulic motor to direct a prioritized flow of hydraulic fluid to the low-pressure side.

Methods can comprise charging a first hydraulic device of a first hydraulic circuit with a first quantity of hydraulic fluid from a hydraulic fluid source. The methods can further comprise pressurizing a control segment and locking the first quantity of hydraulic fluid from exiting the first hydraulic circuit in response to hydraulic pressure within the control segment. The methods can also include unlocking the first quantity of hydraulic fluid to permit exiting of the first quantity of hydraulic fluid from the first hydraulic device in response to dropping the hydraulic pressure within the control segment after a delay. Hydraulic apparatus can comprise a normally open hydraulic pilot operated control valve that can be configured to hydraulically lock a first hydraulic device in response to a hydraulic pressure within a control segment rising to greater than or equal to an actuation pressure.

A pig pumping unit is provided that allows eight passes to be made simultaneously with a single pumping unit. A single engine is used to drive three or four pumps, each connected into separate pumping units. Two engines may thus be used to drive up to eight pumps in a single trailer.