263 results about "Crosshead" patented technology

A connecting rod assembly includes a crosshead for coupling a connecting rod to a plunger, the crosshead having a hole extending through the crosshead. The connecting rod assembly also includes a knuckle cage positioned within the crosshead, the knuckle cage extending through the hole and including a cutout to provide access to a passage formed in the knuckle cage. The connecting rod assembly further includes a knuckle positioned within the passage of the knuckle cage, the knuckle having a mounting surface that is substantially planar, the mounting surface coupling to the connecting rod at a mating end with a substantially planar mating end surface.

An internal combustion engine has a uniblock that defines a blind cylinder bore that terminates within the uniblock. A piston is inserted into the cylinder bore from a bottom end of the cylinder bore. Parallel first and second vertical planes extend along first and second lateral sides of the cylinder bore. A cylinder zone being defined between the first and second vertical planes. A crosshead is coupled to the piston. A first crankshaft has a first crankshaft axis that extends parallel to the first vertical plane and that is positioned outside of the cylinder zone. A second crankshaft has a second crankshaft axis that extends parallel to the second vertical plane and that is positioned outside of the cylinder zone. The first crankshaft is coupled to the crosshead with a first connecting rod and the second crankshaft is coupled to the crosshead with a second connecting rod.

An electrically actuated propeller pitch control system includes a propeller hub assembly, a propeller assembly, and a crosshead drive system. The propeller hub assembly rotates about the central axis during operation of watercraft. The propeller assembly is configured to selectively rotate a propeller blade. The crosshead drive system includes an electric motor, a transmission, and a lead screw that rotates about the central axis.

The reciprocating compressor comprises a compressor frame, a crankshaft and a connecting rod, connecting the crankshaft to a crosshead. A piston rod connects a piston to the crosshead. The piston reciprocates in a gas compression cylinder. At least one pressure-drop module is positioned between the gas compression cylinder and a crosspiece guide. The piston rod extends from the gas compression cylinder through a pressure-drop chamber of the pressure-drop module. Also disclosed herein is a method of operating a reciprocating compressor.

The present disclosure relates to a crosshead box and a plunger pump. The crosshead box is a substantially rectangular box formed by an integral forming manufacturing process. The crosshead box is provided with a plurality of crosshead inner cavities, and the plurality of crosshead inner cavities are arranged in the transverse direction of the crosshead box. The crosshead box is further provided with a plurality of gas discharging cavities, and each gas discharging cavity penetrates through the crosshead box in the longitudinal direction of the crosshead box and is communicated with the corresponding crosshead inner cavity. The plunger pump is provided with the crosshead box. According to the crosshead box and the plunger pump of the present disclosure, the service life is greatly prolonged by means of integral forming, and the gas pressure in the box can be kept balanced all the time during operation, thereby improving the operation stability of the device, and thus further prolonging the service life.

The invention provides an intelligent air flow adjusting system and method for a reciprocating compressor, and the method comprises the steps: obtaining the real-time pressure, flow and rotating speed data during the operation of the compressor, collecting the state of an air valve and the stress parameter of a crosshead pin through a sensor, and determining the specific distribution condition of the current load and compression work; after the target parameter sequence is obtained, the response time of an executing mechanism is adjusted by adopting a dynamic optimization algorithm according to the opening degree and rotating speed control of the gas flow adjusting valve, and a real-time instruction set of adjusting actions is determined; according to the real-time instruction set, a servo motor drives an air valve and a frequency converter to adjust the rotating speed, and the actual air volume adjusting result and energy consumption data of the compressor under the current load are obtained; according to the adjustment scheme of stress balance, finite element analysis is adopted to simulate the long-term change trend of mechanical wear, and stable operation parameters of the air flow adjustment system under the condition that wear is reduced are determined; and according to the optimization adjustment strategy, the operation logic of the compressor is updated by adopting a self-adaptive control algorithm, and a dynamic response instruction set during next load change is determined.

The application provides a cast power end frame including a pair of end plates and an outer casing extending between the end plates and defining an interior therein; a crank shaft housing extending between the end plates and within the interior of the outer casing, and a plurality of crosshead tubes, each crosshead tube extending substantially perpendicular to the crank shaft housing, wherein the outer casing, crank shaft housing, and crosshead tubes are cast as a single part comprising steel comprising a carbon constituent of 0.06%-1.99% carbon.

The embodiment of the invention provides an oil supply system for a low-speed diesel engine bench test, which is provided with at least two lubricating oil cabinets, a first oil outlet header pipe, a second oil outlet header pipe, a test run line, an oil feeding line, a lubricating oil cooler, a first diesel engine and a second diesel engine, a first oil outlet valve and a second oil outlet valve of each lubricating oil cabinet are connected with a first oil outlet main pipe and a second oil outlet main pipe respectively, the test run line and the oil feeding line respectively comprise two output branches, the first test run output branch is connected with a crosshead lubricating oil pipe or a hydraulic oil pipe of a first diesel engine, and the second test run output branch is connected with the first diesel engine. The first oil feeding output branch is connected with a crosshead lubricating oil pipe or a hydraulic oil pipe of a second diesel engine, the second oil feeding output branch is connected with the second diesel engine, and all the parts are connected to a test run line and an oil feeding line through pipelines, so that multiple oil supply modes are met, and meanwhile, the two diesel engines can work in the same time period. One machine is used for feeding oil, and the other machine is used for testing.

An internal combustion engine has a uniblock that defines a blind cylinder bore that terminates within the uniblock. A piston is inserted into the cylinder bore from a bottom end of the cylinder bore. Parallel first and second vertical planes extend along first and second lateral sides of the cylinder bore. A cylinder zone being defined between the first and second vertical planes. A crosshead is coupled to the piston. A first crankshaft has a first crankshaft axis that extends parallel to the first vertical plane and that is positioned outside of the cylinder zone. A second crankshaft has a second crankshaft axis that extends parallel to the second vertical plane and that is positioned outside of the cylinder zone. The first crankshaft is coupled to the crosshead with a first connecting rod and the second crankshaft is coupled to the crosshead with a second connecting rod.

The utility model discloses a plunger pump, and belongs to the technical field of oil and gas exploitation, the plunger pump comprises a pull rod, a crosshead, a bearing bush, a connecting rod and a detection piece, one end of the pull rod is fixedly connected with the crosshead, the other end of the crosshead is connected with the connecting rod, and the bearing bush is arranged between the crosshead and the connecting rod; the crosshead is provided with a detection hole, one end of the detection hole extends to the end face of one end, facing the bearing bush, of the crosshead, and the detection piece detects the temperature of the bearing bush through the detection hole. According to the plunger pump, whether the bearing bush of the crosshead is burnt or not can be determined by detecting the working temperature of the bearing bush of the crosshead in the plunger pump, so that a new bearing bush can be replaced in time, the plunger pump can be prevented from being greatly damaged, and it is guaranteed that normal operation can be conducted stably.

The utility model discloses a four-pump-head plunger type metering pump, which relates to the technical field of metering pumps, and is characterized in that the four-pump-head plunger type metering pump comprises a transmission shaft, eccentric wheels are fixedly arranged at the two ends of the transmission shaft, eccentric shafts are eccentrically arranged on the sides, away from the transmission shaft, of the eccentric wheels, and the eccentric shafts are arranged on the transmission shaft. Two groups of connecting rods are rotationally arranged on each eccentric shaft and are distributed on the two sides of the corresponding eccentric shaft; the cross head is arranged at the end, away from the eccentric shaft, of the connecting rod, the end, close to the connecting rod, of the cross head is hinged to the connecting rod through a cross head pin, and the periphery of the cross head is sleeved with a cross head bush which is used for guiding the cross head in the axial direction and limiting the cross head to reciprocate in the axial direction. The four pump heads are driven by the second motor, the flow and the discharge pressure of each pump head can be different, and quantitative output of different media or the same medium at the same injection point or different injection points can be completed.

The present invention provides an electromagnetic compressor, including a compressor cylinder body, with dead center coils designed at both ends of the compressor cylinder body, and the electromagnetic directions of the coils are opposite to each other with the same poles in the compressor cylinder body after power is applied; a piston coil is provided between the two sets of dead center coils, and the positive and negative poles of the piston coils are electrically connected to the commutator through a guide rod. After the guide rod is connected to the commutator, the piston coil is urged to approach the dead center coil on the opposite side. During the movement of the commutator and the piston head, the position of the guide rod relative to the commutator will change relative to each other, thereby changing the connection direction of the positive and negative poles of the piston coil. The present invention designs a piston compressor based on the principle of electromagnetic induction, and utilizes the same magnetic poles generated at both ends of the cylinder body to make the piston continuously change the magnetic poles at both ends and reciprocate in the cylinder body. The present invention eliminates the crankshaft, crosshead, coupling, motor transmission mechanism, etc. in the traditional piston compressor, and has a simple structure.

The invention discloses a single-cylinder crankshaft upper crank contour optimization composition method which comprises the following steps: firstly, analyzing a single-cylinder inner crank-connecting rod-crosshead motion rule, and finding out a corresponding relation between each motion parameter and a crank contour; the crank, the connecting rod and the crosshead are integrally and reversely rotated, and point location data of the rotating center of the connecting rod and the crosshead are obtained; setting a safety interval and a vertical line to obtain point position data of an intersection point of the crosshead movement line and the crank contour limiting line and tangent point data of the crank contour limiting line on the crank contour; repeating the operation according to the adjusted angle value to obtain a plurality of groups of tangent point data; fitting and processing the multiple groups of tangent point data to obtain a first group of crank limit profile curves and a second group of crank limit profile curves, shifting the outer circle of the crank pin to obtain an auxiliary profile, and connecting the three to obtain a crank profile. According to the method, the contour of the crank can be designed to the maximum extent, the balance performance of the crank is effectively improved, and the application applicability of the crankshaft is enhanced.

The invention discloses a high-power seven-cylinder fracturing pump shell and a fracturing pump in the technical field of fracturing pumps, and aims to solve the problems that in the prior art, the requirements of high pressure and large displacement of a construction site are difficult to meet, and the stability of the whole structure of the fracturing pump is poor. The pump shell comprises a pump shell body, the pump shell body comprises two side bearing seats, the side walls of the two side bearing seats are provided with the same upper arc plate and the same lower arc plate, and a rearview hole cover plate and a connecting rod crosshead box body are arranged between the upper arc plate and the lower arc plate; according to the seven-cylinder fracturing pump shell structure type, under the same rotating speed and stroke working conditions, compared with a five-cylinder fracturing pump, the seven-cylinder fracturing pump is higher in displacement, larger in pressure and lower in discharge pulsation, and the requirements for large displacement and high pressure of a well site can be better met; and meanwhile, through cooperation of the multiple reinforcing rib plates, the stability of the overall structure of the device is ensured, and the using effect of the device is ensured.

The invention provides an oil field profile control pump which comprises an outer shell. The inner shell is arranged on one side of the outer shell; the eccentric wheel is mounted in the outer shell; the connecting rod is connected with the eccentric wheel; the pin shaft is arranged in the inner shell, and the pin shaft is connected with the other end of the connecting rod; the crosshead is fixedly connected with the pin shaft; a connecting thread is arranged at one end of the plunger rod, and the plunger rod is connected with the crosshead through the connecting thread; the connector is arranged at the end of the plunger rod, the plunger rod is connected with the outer shell, a sealing ring is arranged on the outer side of the plunger rod, the plunger rod is connected with a gland, and the gland is fixed to the outer shell through a bolt. The fracture cannot easily occur.

The invention provides an electromagnetic compressor which comprises a compressor cylinder body, stop point coils are designed at the two ends of the compressor cylinder body, and the same poles of the stop point coils are opposite in the compressor cylinder body after the stop point coils are electrified; a piston coil is arranged between the two groups of stop point coils; and positive and negative poles of the piston coil are electrically connected with the commutator through guide rods. After the guide rod is connected with the commutator, the piston coil is driven to approach the dead center coil on the opposite side. In the moving process of the reverser and the piston head, the position of the guide rod relative to the reverser can be changed relatively, and then the connection direction of the positive electrode and the negative electrode of the piston coil is changed. The piston type compressor is designed based on the electromagnetic induction principle, the same magnetic poles generated at the two ends of the cylinder body are utilized, the magnetic poles at the two ends of the piston are continuously changed, the piston reciprocates in the cylinder body, a crankshaft, a crosshead, a coupler, a motor transmission mechanism and the like in a traditional piston type compressor are omitted, and the piston type compressor is simple in structure.

The invention discloses a long-stroke fracturing pump power end and a fracturing pump, and relates to the technical field of reciprocating pumps, and the power end comprises an input shaft assembly, a crankshaft gear, a crankshaft assembly, a rocker, a subdivision sliding block, a crosshead, an integral sliding block, a pump body, a sliding shoe and a rocker shaft. External power drives the input shaft assembly to rotate, the input shaft assembly drives the crankshaft assembly to rotate through the crankshaft gear so as to drive the subdivision sliding block to slide, the subdivision sliding block drives the rocker to swing in a reciprocating mode from the middle of the rocker, and the integral sliding block on the lower portion of the rocker drives the crosshead to do synchronous reciprocating motion. The stroke of the crosshead is far greater than the rotation diameter of the crankshaft due to the displacement amplification effect of the rocker, so that the long stroke of the fracturing pump is realized; the crankshaft is arranged right above the sliding shoe, a connecting rod in a traditional fracturing pump is omitted, the stroke of the fracturing pump is increased, but the length is reduced, and the weight is not increased; the fracturing pump power end and the fracturing pump are long in stroke, low in stroke frequency, long in service life of quick-wear parts, compact in structure and convenient to assemble and disassemble.

A liquid nitrogen pump power end assembly relates to the technical field of liquid nitrogen pumps and comprises a crankshaft box body, a crankshaft, a connecting rod and a crosshead assembly. A plurality of wallboards are arranged in the crankshaft box body, crankshaft bearing seats are mounted on the wallboards, a plurality of reinforcing ribs are fixedly arranged between the crankshaft bearing seats and the wallboards, and the crankshaft is rotationally mounted in the crankshaft bearing seats through crankshaft bearings; the crankshaft comprises a straight shaft and an eccentric wheel, the straight shaft penetrates through the crankshaft bearing seat, and the eccentric wheel is mounted on the straight shaft and connected with the connecting rod; the crosshead assembly comprises a crosshead, the inner end of the crosshead is connected with the connecting rod, the outer end of the crosshead is arranged as a mounting end, and a clamping assembly is mounted at the mounting end; the clamping assembly comprises two oppositely-arranged clamping hook pieces, and the distance between the two clamping hook pieces is adjustable in the radial direction of the installation end. The mechanical strength of the crankcase body can be improved, and the gradually-increased operation pressure in China can be met; and the device can be connected with fluid ends of various models, and the installation application range is expanded.

This reciprocating compressor comprises: a crankshaft; a crosshead part that is connected to the crankshaft; a cross guide part that accommodates the crosshead part; and a compression part that is placed on the cross guide part. The cross guide part includes: a plurality of column parts each continuing from the lower end to the upper end of the cross guide part on one outer wall of wall parts constituting the cross guide part; and one or more recessed shape parts formed in a recessed shape so as to be thinner than the plurality of column parts between the plurality of column parts in a first direction in which the crankshaft extends.

The utility model relates to an adjusting and positioning device for machining a crosshead pin of a variable compression ratio part. Comprising a basic positioning mechanism arranged on a working table of a vertical turning and milling machine tool of the machine tool, a V-shaped base used for placing the crosshead pin, an adjustable supporting mechanism used for axially positioning the crosshead pin, and a pressing mechanism used for pressing the V-shaped base and the crosshead pin. All positioning and clamping precision of the crosshead pin before finish machining can be effectively controlled during operation, correction and adjustment are convenient and efficient, the surface of the crosshead pin is effectively protected, and it is ensured that all procedures are finished through one-time clamping station finish machining of all profiles of a piston hole of the crosshead pin on a vertical turn-milling machine tool.

The utility model relates to a tool for disassembling and assembling a connecting rod in a vertical compressor. The tool comprises a clamping assembly, a disassembling and assembling assembly and a base plate. During disassembly and assembly, the clamping assembly and the head of the crosshead are oppositely clamped and fastened, the base plate is matched with the bottoms of the two sides of the lower portion of the crosshead, when the crosshead is disassembled and assembled, the clamping assembly and the head of the crosshead are oppositely clamped and fastened, the cable penetrates through the filling hole from the air cylinder and then is connected with the lifting ring nut, and therefore the whole crosshead is lifted. The cushion plate and the connecting plate of the cushion plate are arranged at the proper positions of the bottoms of the two sides of the lower portion of the crosshead to be assembled and connected into a whole, then the bottom faces of the two sides of the lower portion of the crosshead body including the connecting rod slowly descend to be located on the cushion plate of the cushion plate assembly so as to guarantee stability of the crosshead, and finally the crosshead pin is disassembled through the disassembling and assembling assembly. Therefore, the control gap and the center height of the crosshead can be guaranteed when the crosshead is disassembled and assembled, stability is kept, collision is prevented when the crosshead is disassembled and assembled, and working efficiency and safety of the crosshead are improved.

The utility model discloses a combined compressor which comprises a motor and further comprises a first-stage compressor body, a second-stage compressor body, a third-stage compressor body, a fourth-stage compressor body, a compressor body, a middle body, a compressor body, a connecting rod, a crosshead, a piston rod, a connecting cylinder, a pressure body B and a pressure body C. The power output end of the motor is provided with the first-stage compressor body, the second-stage compressor body, the third-stage compressor body and the fourth-stage compressor body through the compressor bodies. The machine body is composed of a middle body and a machine body, the device is of an eight-column eight-stage counter-dynamic balance type, air cylinder water cooling, pressure circulating lubrication and motor dragging, all columns of air cylinders are horizontally arranged and distributed on the two sides of a crankshaft, the device has the advantages of being good in dynamic balance performance, convenient to operate and overhaul and the like, the motor is of a dual-drive structure, four columns of compressor units are arranged on each side of the motor, the overall structure is optimized, and the service life is prolonged. The staggered angles of the cranks among the rows are reasonably arranged, the inherent frequency of a shaft system is changed, the torsional vibration of the shaft system can be effectively reduced, the jumping problem of the crankshaft is greatly relieved, and therefore vibration and noise of a unit are greatly reduced.

The high-precision piston rod connecting structure comprises a piston rod, the upper end of the piston rod is connected with a piston body, the lower end of the piston rod is connected with a crosshead, the upper end of the crosshead is connected with a positioning flange with a center hole, and the lower end of the piston rod is a reducing end transited through a conical surface section. The reducing end penetrates through the center hole of the positioning flange and is stretched and locked by a first fastening structure; the upper section of the center hole of the positioning flange is a taper hole matched with the conical surface section of the piston rod; the upper end of the piston rod penetrates into a center hole of the piston body, is stretched and locked by a second fastening structure and is provided with an anti-rotation structure. Automatic centering is achieved through conical surface matching, stable pre-tightening force is provided in cooperation with a double-fastening structure, the problems that a traditional connecting structure is insufficient in precision and poor in locking reliability are effectively solved, the operation precision and stability of a compressor are greatly improved, and meanwhile the compressor connecting structure has the advantages of being convenient to install and maintain and long in service life.

The utility model discloses a cooling device for a ball screw of an all-electric injection molding machine, which comprises the ball screw, one end of the ball screw is in threaded connection with a ball nut, the outer part of the ball nut is connected with a crosshead thrust seat, the middle part of the crosshead thrust seat is provided with a flow guide assembly, one side of the crosshead thrust seat is provided with a cooling assembly, and the other side of the crosshead thrust seat is provided with a water inlet and a water outlet. The output end of the cooling assembly is communicated with the flow guide assembly through a pipeline, after gas filtered by the gas source is treated by the vortex cooler, cooling gas is conveyed into the crosshead thrust seat through cooperation of a gas pipe and a gas pipe connector, a closed cavity formed by combining the crosshead thrust seat and the ball nut is filled with the cooling gas, and the crosshead thrust seat and the ball nut are sealed. The surface of the outer body of the ball nut is coated with the cooling gas, and the cooling gas with heat of the ball nut is exhausted through the exhaust pipeline and the silencer at the lower part of the crosshead thrust seat, so that the heat of the ball nut is taken away through continuous flowing of the cooling gas, the heat dissipation effect of the ball nut is improved, and the mold closing rate of the injection molding machine is increased.

A batch drum furnace with a dual cylinder is provided. In one embodiment, a batch drum furnace configured to heat a hot melt adhesive material includes a platen assembly configured to be movable from a raised position to a lowered position; a horizontal crosshead member which is suspended on the horizontal crosshead member; and a dual pneumatic piston assembly configured to move the platen assembly from the raised position to the lowered position. The pneumatic piston assembly includes a first pair of pneumatic pistons disposed on a first side of the drum furnace and a second pair of pneumatic pistons disposed on a second side of the drum furnace, and each pair of pneumatic pistons includes a first piston rod and a second piston rod, each piston rod having an upper end. In one embodiment, the upper end of the first piston rod is connected to the upper end of the second piston rod through first and second top connecting plates; and wherein the first and second top connecting plates are connected to opposite ends of the horizontal crosshead member by elongated crosshead struts.

A crosshead type large turbocharged two-stroke uniflow internal combustion engine (100) has a telescoping tube (30) mechanically connected to a cylinder frame (29) and a crosshead (9) and fluidly connecting a source of pressurized lubricating and cooling medium to a conduit (25) in the crosshead (9), a piston rod (15) and a piston (10) to cool the piston (10).

The invention relates to the technical field of compressor equipment, in particular to a crosshead hydraulic connecting and fastening device of a BOG compressor, which comprises a thrust ring, a positioning ring, a pressure body, a locking nut and a follow-up ring. The crosshead is located at one end of the piston rod, and the thrust ring, the positioning ring and the pressure body are sequentially arranged on the piston rod and are coaxial. And an oil cavity is arranged in the pressure body. And a pressure piston and a sealing ring are arranged in the oil cavity. The locking nut is connected with the pressure body in a sleeved mode and matched with the pressure body in a threaded mode, and the locking nut is in ball hinge with the follow-up ring. According to the crosshead hydraulic connecting and fastening device of the BOG compressor, after the pressure of the oil cavity is relieved, the required connecting pre-tightening force is achieved between the piston rod and the crosshead, and if the locking nut has the tendency of axial deviation, the locking nut will promote the follow-up ring to rotate relative to the locking nut, the stress of the locking nut is balanced, and the service life of the follow-up ring is prolonged. Therefore, the piston rod is prevented from being bent, and normal use of the piston rod is guaranteed.

The transmission structure comprises a connecting rod and a crosshead, the connecting rod is provided with a connecting part, the crosshead is provided with a fixing pin, the fixing pin is connected to the connecting part in an inserted mode, and a transmission assembly is arranged on the radial outer wall of the fixing pin. The transmission assembly is matched with the connecting part to achieve rotation of the connecting part around the rotating axis on the fixing pin, the crosshead is provided with an oil inlet channel, the fixing pin is provided with an axial oil way and a radial oil way communicated with the oil inlet channel, and the radial oil way comprises a first oil way and a second oil way. Lubricating oil can enter from the oil inlet channel and sequentially pass through the first oil way, the axial oil way and the second oil way to enter the transmission assembly, the lubricating function is achieved, rotating connection is achieved by arranging the transmission assembly, abrasion and loosening caused by the fact that the fixing pin directly participates in friction are avoided, and the good lubricating function is achieved by arranging the multiple oil ways; and the crosshead can adapt to a high-speed application scene.

The utility model relates to the technical field of plunger pumps, and discloses a fracturing plunger pump, a power end assembly of the fracturing plunger pump comprises a power end shell, a connecting rod body crosshead assembly and a crankshaft assembly, one side of the connecting rod body crosshead assembly is connected with a crankshaft of the crankshaft assembly, and the other side of the connecting rod body crosshead assembly is installed in a crosshead cavity of the power end shell; the power end shell comprises a plurality of crosshead cylinder sleeves, a plurality of crankshaft bearing pedestals and a plurality of vertical plates, the crankshaft bearing pedestals are installed on the vertical plates in a one-to-one correspondence mode, and a first containing cavity used for containing a crank throw of a crankshaft is formed between every two adjacent crankshaft bearing pedestals. A second containing cavity used for containing the crosshead cylinder sleeves is formed between every two adjacent vertical plates, each crosshead cylinder sleeve is provided with a crosshead cavity, and the crosshead cavities communicate with the first containing cavities. The reliability of the plunger pump can be improved through the vertical plates of the power end shell, the plunger pump is simple, reasonable and compact in overall structure, and light weight of the plunger pump is achieved.

A pump assembly may include a bearing housing having a bore. The pump assembly may include a connecting rod connected to the bearing housing at a first end of the connecting rod and connected to a crosshead at a second end of the connecting rod via a wrist pin. The connecting rod may include a lubrication channel that extends within the connecting rod. The pump assembly may include a shell bearing in the bore of the bearing housing, the shell bearing having an inner surface and an outer surface. A portion of the inner surface of the shell bearing that contacts the crankshaft in a forward stroke of the crosshead may be uninterrupted by a groove or an aperture configured to direct lubrication fluid to the lubrication channel of the connecting rod.