A crosshead part for drilling pumps includes an upper guide plate, a lower guide plate and a crosshead, wherein the crosshead reciprocates in a straight line between the upper guide plate and the lower guide plate; at least one of the upper and lower guide plates has an oil inlet for introducing external lubricating oil between the at least one of the upper and lower guide plates and an arc surface of the crosshead. A crosshead system for drilling pumps includes a lubricating pipeline system and the crosshead part. The lubricating pipeline system includes a main pipeline and N branch pipelines. A drilling pump includes the crosshead part or the crosshead system.

A machine includes a liquid lubrication system and a shaft, the shaft being rotatable about a rotation axis, the shaft including a first part, a second part engaged coaxially with the first part, and a journal bearing between the first part and the second part, the first part being rotatable relative to the second part about the rotation axis, a helical feature disposed between the first part and the second part and configured to define a helical pump between the first part and the second part, the pump being hydraulically connected to the liquid lubrication system, the journal bearing being disposed adjacent to the helical feature.

An annular scraper ring assembly for a packing arrangement is disclosed. The annular scraper ring assembly can form a seal with a plunger included in a fluid end of a reciprocating pump and includes two or more rings, including a first ring and a second ring. The first ring is formed from a resilient material configured to form a seal against a plunger included in a fluid end of a reciprocating pump and includes an upstream face and an inner surface. The second ring defines a caroming surface configured to engage the upstream face of the first ring and cam the inner surface inwards when the first ring is compressed against the second ring.

An annular scraper ring assembly for a packing arrangement is disclosed. The annular scraper ring assembly can form a seal with a plunger included in a fluid end of a reciprocating pump and includes two or more rings, including a first ring and a second ring. The first ring is formed from a resilient material configured to form a seal against a plunger included in a fluid end of a reciprocating pump and includes an upstream face and an inner surface. The second ring defines a caroming surface configured to engage the upstream face of the first ring and cam the inner surface inwards when the first ring is compressed against the second ring.

An annular scraper ring for a packing arrangement is disclosed. The annular scraper ring that can form a seal with a plunger included in a fluid end of a reciprocating pump and includes a planar upstream face and an inner surface with a tapered section. The tapered section tapers away from the plunger along a downstream direction so that the scraper ring is widest at the planar upstream face.

An annular scraper ring for a packing arrangement is disclosed. The annular scraper ring that can form a seal with a plunger included in a fluid end of a reciprocating pump and includes a planar upstream face and an inner surface with a tapered section. The tapered section tapers away from the plunger along a downstream direction so that the scraper ring is widest at the planar upstream face.

Disclosed is a turbine fracturing apparatus. The turbine fracturing apparatus includes: a main power assembly and an auxiliary power assembly. The main power assembly includes a first power source and a piston pump connected to the first power source; the first power source outputs power to the piston pump, and the piston pump outputs a first liquid. The auxiliary power assembly includes a second power source, a load sensitive system connected to the second power source, and an auxiliary power device; the second power source outputs power to the load sensitive system, the load sensitive system is connected to the auxiliary power device and outputs a second liquid for the auxiliary power device. The first liquid is different from the second liquid, and the first liquid and the second liquid have certain pressure. The load sensitive system is configured to regulate a pressure of the second liquid in real time according to pressure of the second liquid required by the auxiliary power device.

The refrigerant compressor includes a compressor casing (2); an oil sump (13) arranged in the compressor casing (2); and an oil level sensor arrangement (14) configured to detect an oil level in the oil sump (13), the oil level sensor arrangement (14) including a tubular element (16) secured to the compressor casing (2) and a floating element (17) surrounding the tubular element (16) and being movably mounted with respect to the tubular element (16). The compressor casing (2) includes a passage opening (24) and dimensions of the tubular element (16), the floating element (17) and the passage opening (24) are defined to allow an insertion and a removal of the tubular element (16) and the floating element (17) into and out of the compressor casing (2) through the passage opening (24).

In order to avoid over-lubrication of the cylinders (2) in a piston compressor (1) and to reduce the amount of lubricant to a level required for operation, according to the invention, a lubricating system having a lubricating system control unit (14) is provided, in which system at least one lubricant sensor (15) is provided for detecting a lubricating film measurement variable (S) representative of a lubricating film thickness of a lubricating film (11) on the cylinder surface of the cylinder (2), the lubricating system control unit (14) being designed to operate the lubricating system at least once in a predetermined calibration operating mode during operation of the piston compressor (1) and to determine a lubricating film state value (SZ) on the basis of the lubricating film measurement variable (S) detected during execution of the calibrating operating mode and the lubricating system control unit (14) being designed, after the end of the calibration operating mode during operation of the piston compressor (1), to control the amount of lubricant to be introduced depending on the determined lubricating film state value (SZ).

A pump system includes a housing, a lubricant system, and control circuitry. The housing includes a pump chamber defined by the housing and a throat seal. The lubricant system includes a lubricant pump, a lubricant gallery defined within the housing of the main pump, and a lubricant circuit fluidly connecting the lubricant pump and the lubricant gallery. The throat seal is disposed adjacent to and between the pump chamber and the lubricant gallery. The control circuitry is configured to cause the lubricant pump to pump a purge volume of lubricant through the lubricant system, cause the lubricant pump to stop pumping for a first time period after the lubricant pump has pumped the purge volume, and cause the lubricant pump to pump the purge volume of lubricant through the lubricant system after the first time period.