Abstract: The present invention relates to a compression chamber unit (1) of an air pump, comprising a cylindrical body part (3) provided with at least one outlet nozzle (4), a number of connecting flanges (6) and a number of connecting bosses (7), wherein the cylindrical body part (3) is an extruded cylinder and a cap (2) is formed with outlet nozzle (4), connecting flanges (6) and connecting bosses (7), where the cap (2) is adapted to engage with a first end part (10) of the cylindrical body part (3). The present invention further more relates to a method for forming a compression chamber unit (1) which method comprises the following steps: the cylindrical body part (3) is extruded, and the cap (2) is moulded onto the cylindrical body part (3).

Abstract: A cylinder realizing reduced reciprocation friction between a piston ring and a bore surface of the cylinder in a region where the piston ring slides. The cylinder in which a piston slides on a bore surface of the cylinder. A plurality of recesses is formed in a stroke center region in the bore surface of the cylinder. The stroke center region is a region between an under face position of a ring groove for a bottom piston ring at a top dead center of the piston and a top face position of a ring groove for a top piston ring at a bottom dead center of the piston. The total of areas of all of the recesses is in the range of 1% to 80% when an area of the stroke center region is 100%, and the recesses are not formed in a region other than the stroke center region of the bore surface of the cylinder.

Abstract: A method and apparatus for maintaining a seal between a cylinder and a fluid manifold for a reciprocating force delivery device is disclosed. A cylinder retention assembly comprises a rotatable member with a variable topography surface. The rotatable member is disposed against a stop extending outwardly from the cylinder, and is fastened to the fluid manifold by a locking ring. When rotated, the rotatable member produces an axial force on the locking ring and the cylinder, urging the cylinder against the fluid manifold. The cylinder retention assembly may be used in reciprocating pumps and compressors.

Abstract: Apparatus and method for securing a cylinder liner to a pumping module. A first part of an assembly housing pistons is fastened to a pumping module and a second part of the assembly is brought against the first so that the pistons act on tensioning plates which each have a stud rod extending therefrom through the assembly at an end distal to the pumping module. Each rod has a first portion substantially surrounded in an elastomeric member and a second portion threaded to receive a nut. The rods are passed through a clamping ring on the cylinder liner and the nut is attached to the rod. Actuating the pistons causes initial compression of the elastomeric member by the tension plate and allows tightening of the nut toward the pumping module. Release of the pistons then causes expansion of the elastomeric member to urge the cylinder liner towards the pumping module.

Abstract: A piston pump includes a pump housing having a suction port, a discharge port, and an internal cavity; a first cylinder member having a cylinder bore; a piston built into the cylinder bore of the first cylinder member to thereby form a pump chamber and adapted to change the volume of the pump chamber by means of axially reciprocating movement; a suction valve provided in the piston; and a discharge valve provided at the discharge side of the pump chamber. A circumferential protrusion is formed externally at an axially intermediate portion of the first cylinder member. The first cylinder member is press-fitted, at the circumferential protrusion, into the internal cavity of the pump housing. A leading end portion of the first cylinder member from which the first cylinder member is inserted into the pump housing has a diameter smaller than that of the internal cavity of the pump housing.

Abstract: An air compressor that employs splash lubrication to lubricate and cool a piston kit that includes a cylinder and a piston reciprocating in the cylinder. In one form, cooling channels can be coupled to or formed on the cylinder to direct the lubricant that is splashed onto the cylinder to drain in a desired manner, such as helically around the exterior of the cylinder, to more effectively cool the piston kit. In another form, the cylinder can include an annular flange that can be bigger in diameter than a remainder of the cylinder. The annular flange can be received into a counterbore in a cylinder block. A cylinder head, which can be fastened to the cylinder block, can apply a clamping force to the annular flange to clamp or fix the cylinder to cylinder.

Abstract: Apparatus and method for securing a cylinder liner to a pumping module. A first part of an assembly housing pistons is fastened to a pumping module and a second part of the assembly is brought against the first so that the pistons act on tensioning plates which each have a stud rod extending therefrom through the assembly at an end distal to the pumping module. Each rod has a first portion substantially surrounded in an elastomeric member and a second portion threaded to receive a nut. The rods are passed through a clamping ring on the cylinder liner and the nut is attached to the rod. Actuating the pistons causes initial compression of the elastomeric member by the tension plate and allows tightening of the nut toward the pumping module. Release of the pistons then causes expansion of the elastomeric member to forcibly compel the cylinder liner towards the pumping module.

Abstract: One embodiment of the invention relates to a liner for a first pump housing in a fluid pump assembly. The fluid pump assembly includes a first pump housing, a second pump housing and a flexible diaphragm disposed between the first and second pump housings. The first pump housing includes a fluid access port for providing fluid communication between an inside housing chamber of the first pump housing and an outside of the first pump housing. The second pump housing is securely mated to the first pump housing. The second pump housing includes a biasing mechanism for selectively displacing a portion of the diaphragm toward the first pump housing. The liner of the invention includes a flexible member removeably secured inside the first pump housing. The liner also includes a first portion of the member being shaped to substantially conform to the interior dimensions of the inside housing chamber and a second portion of the member shaped to substantially conform to the fluid access port.

Abstract: An engine cylinder liner is provided. The engine cylinder liner includes a first liner end, a second liner end, and an inner surface extending between the first liner end and the second liner end. The engine cylinder liner also includes a first outer surface between the first liner end and a first outer surface end portion, and a second outer surface between the second liner end and a second outer surface end portion. The second outer surface end portion is closer to the first liner end, than the first outer surface end portion is to the first liner end. The engine cylinder liner further includes an inclined shoulder surface portion between the first and second outer surface end portions.

Abstract: There is disclosed a hydraulic actuating device for actuating a shift rod in particular of a gearbox for motor vehicles, which comprises a cylinder chamber provided in or on a gear housing for accommodating a shift piston which is actively connected to the shift rod and which divides the cylinder chamber into two working chambers which can selectively be acted upon by a pressure medium from a reservoir for the latter, said working chambers being separated from one another by means of a sealing arrangement arranged on the shift piston. The sealing arrangement is designed in a valve-like manner so that, when at least one working chamber is acted upon by pressure medium, it connects said working chamber to an auxiliary chamber which is delimited by the sealing arrangement and which in turn can be connected to the reservoir for the pressure medium.

Abstract: A cylinder liner for use in a cylinder crankcase includes a liner body having at least one end face, and a material strip. The material strip is affixed to the liner body and projects axially from the at least one end face of the liner body.

Abstract: Two-stage double-acting hydraulic cylinders are described, in which a first, inner stage includes a piston rod and head movable within a cylinder and a second, outer stage has a cylindrical body adapted to move longitudinally between stop positions intermediate the ends of the first cylinder. The two stages are hydraulically linked to each other through the alternate introduction of hydraulic fluid selectively through an extension pressure fluid port and a retraction pressure fluid port a limited motion of the outer stage is obtained in a power stroke. Hydraulic power means of this kind is of particular value in powered apparatus for digging and transplanting trees, where minimization of the overall height of the apparatus is desirable.

Abstract: Apparatus and method for applying radial compressive stress pre-loading to a cylinder liner. A cylinder housing is attached to a pump, and a cylinder liner is disposed within the cylinder housing. A fluid inlet in fluid communication with the annular space between the cylinder housing and cylinder liner is disposed on the cylinder housing. The annular space is filled with pressurizing fluid through the fluid inlet, which creates radial compressive stress pre-loading on the cylinder liner.

Abstract: A pneumatic tool includes a rotor, a cylinder, two pads, two covers, two bearings and a collar. The rotor includes a first axle formed thereon and a second axle opposite to the first axle. The cylinder includes a central space for receiving the rotor. Each of the pads is attached to an end of the cylinder and formed with an aperture through which one of the first and second axles is inserted. Each of the covers includes an aperture through which a related one of the first and second axles is inserted. Each of the bearings is attached to a related one of the covers to support a related one of the first and second axles. The collar is provided on the second axle and between the rotor and a related one of the bearings.

Abstract: A self-tightening retaining system for securing a closure in position closing an access port of a pump housing. The system includes a retaining cover for obstructing removal of the closure from a bore of the access port. The cover has external threads interengageable with screw threads of the bore. A locking device is configured for being secured to the cover such that the locking device rotates together with the cover. The locking device has a fastener receivable in a hole of the closure and has external threads interengageable with threads of the hole. The threads of the cover and the threads of the fastener are spiraled in opposite directions such that when the cover rotates in a loosening direction, the fastener becomes tightened in the hole of the closure thereby stopping the rotation.

Abstract: Disclosed is a two-stroke engine, especially for landcraft, watercraft, or aircraft models, comprising a piston which can be moved up and down within a bush, defines a combination chamber at the top, and is connected to a crankshaft via a con-rod at the bottom, said crankshaft being rotatably mounted in a crank housing located below the bush. In order to reduce friction of the piston in the bush of such a two-stroke engine, the bottom end of the bush, which adjoins the crank housing is provided with means that increase the temperature-related radial expansion of the bush.

Abstract: A rotor body (22) having a plurality of cylindrical bores (24) each adapted to receive a piston (30) for reciprocating movement therein, each of the bores (30) being lined with a ceramic liner (42) having a first split (44), and a method of forming a rotor (16) having a ceramic bore liner (42) that includes the steps of providing a rotor body having at least one bore (140), providing a ceramic bore liner having a first end, a second end and a split having a width (142), and compressing the bore liner to decrease the width and securing the bore liner in the at least one bore (144).

Abstract: A cylinder assembly for a linear compressor includes a cylinder chassis with an inner surface defining a cylinder space extending along an axis from a cylinder head end. The cylinder space is at least substantially cylindrical. A cylindrical cylinder liner, open at both ends is located within the chassis. The outer surface of the liner is engaged against the cylinder space defining portion of the inner surface of the chassis. A valve plate is being bonded or fused to the cylinder head end of the cylinder liner. The valve plate sealingly closes the cylinder head end of the cylinder space.

Abstract: A radial piston pump for generation of high fuel pressures in fuel injection systems comprises a pump housing, a pump shaft and at least one cylinder insert, arranged radially to the pump shaft. A cylinder chamber is located within the cylinder insert in which a piston can move back and forth. The cylinder insert is connected with a front face to a flattening of the pump housing, by connecting means. The cylinder insert comprises an inlet port and a high pressure port. The front face of the cylinder insert and/or the flattening of the pump housing comprise precisely machined raised sealing regions for sealing the cylinder insert against the pump housing, which are relatively small in relation to the total front face of the cylinder insert and the total flattening of the pump housing. A high surface pressure is thus achieved in the sealing region.

Abstract: A cylinder liner for insert casting and a method for manufacturing the cylinder liner are provided. The cylinder liner and the method are applied to cylinder blocks and improve the adherence and the bonding strength with a cylinder block material in a favorable manner. The cylinder liner satisfies the following requirements: (i) the height of projections 1P is in a range between 0.5 mm and 1.0 mm, inclusive; (ii) the number of the projections 1P is in a range between 5 and 60, inclusive, per cm2 on the outer circumferential surface; (iii) the area ratio of regions each encircled by a contour line of a height of 0.4 mm is in a range between 10% and 50%, inclusive; (iv) the area ratio of regions each encircled by a contour line of a height of 0.2 mm is in a range between 20% and 55%, inclusive; (v) the region each encircled by a contour line of the height of 0.4 are independent from each other; and (vi) the area of the regions each encircled by a contour line of the height of 0.4 mm is in a range between 0.

Abstract: A pressure enclosure includes a first component having an opening, a second component coupled to the first component in a position over the opening, a third component positioned between the first and second components and covering the opening, and a load chamber defined by a space between the second and third components and configured such that pressure in the load chamber biases the third component against the first component to seal the opening. The pressure enclosure may be a cylinder of a pump for pressurizing fluid or gas, with the first component a cylinder body, the second component an end cap and the third component a valve body, with the load chamber biasing the valve body against the cylinder body.

Abstract: Spacers for use with actuator casings are disclosed. An example spacer includes a ring-shaped member defining a central opening and configured to form a part of an actuator casing and to space first and second actuator casing portions a predetermined distance when the first and second casing portions are coupled to the ring-shaped member. The ring-shaped member includes a first surface surrounding the central opening configured to engage the first casing portion and a second surface surrounding the central opening configured to engage the second casing portion. Each of the first and second surfaces includes a plurality of apertures configured to receive threaded fasteners to attach the first and second actuator casing portions to the ring-shaped member.

Abstract: A high pressure pump for preventing distortion of a sealing surface or a cylinder form. The high pressure pump has an intermediate member including a cylinder body having a pressurizing chamber communicated with a cylinder accommodating a plunger. Fluid in the pressurizing chamber is pressurized by reciprocating the plunger. The intermediate member is arranged between a cover and a flange and is clamped by clamping bolts. An electromagnetic spill valve for receiving reaction force from the pressurizing chamber when the fluid in the pressurizing chamber is pressurized is attached to the cover at a position for reducing the clamping force applied to the intermediate member by the clamping bolts.

Abstract: A hydraulic cylinder comprises a piston assembly with a piston and a piston rod, a cylinder housing with a housing bottom, a pressure chamber in the cylinder housing delimited by the piston and housing bottom, a spring element which prestresses the piston assembly away from the housing bottom, and a fixing element which fixes the piston assembly in a predefined stroke position relative to the cylinder housing prior to first actuation of the hydraulic cylinder and is designed to release the piston assembly relative to the cylinder housing upon first actuation of the hydraulic cylinder. The spring element is arranged on the side of the piston which is remote from the pressure chamber, whereas the fixing element is provided in the pressure chamber at the housing bottom and co-operates with a mating element on the piston to releasably fix the piston assembly relative to the cylinder housing.

Abstract: Methods and apparatus for securing a cylinder liner to a pump module. A tension body is disposed about the cylinder liner and attached to the pump module. A locking body engages the cylinder liner and is threaded to the tension body. A hydraulic load cell is removably attached to the tension body and includes a hydraulic ram arranged to impart a compressive load to the cylinder liner and a tension load in the tension body. The locking body can be adjusted axially to contact the cylinder liner and maintain the applied loads, which act as a pre-load to keep the cylinder liner in contact with the pump module.

Abstract: A frame of a reciprocating compressor includes a main frame having a cylindrical insertion hole to receive a cylinder of a compression unit along a center axis thereof and a flange that supports an outer stator of a reciprocating motor at the outer circumference of the flange. A sub frame is engaged to the main frame by an engaging device and positioned to cover an outer circumferential surface of the cylinder to form an oil flow path in a space between the main frame and the cylinder.

Abstract: Disclosed herein is a linear compressor. In the present invention, the configuration that a sealing protrusion is protruded in a sealing part of a cylinder toward an exhale cover leads line contact with the exhale cover and the sealing protrusion of the sealing part. Even though small power is applied to the exhale cover, the exhale cover and the sealing protrusion are closely adhered to each other, thus effectively sealing the exhale cover and the cylinder. Furthermore, as power transmitted from the exhale cover to the cylinder becomes reduced, a transformation of the cylinder can be prevented, and a performance and reliability of the linear compressor can be enhanced.

Abstract: A cylinder liner (2) for a cylinder block has a contouring (6) at one end. The contouring (6) serves to support the liner (2) on a sleeve (4) inside a die-casting tool. When the liner (2) is cast in, recesses (10) of the liner (2) are filled by the material of the cylinder crankcase whereby preventing the liner (2) from seating toward an oil chamber (14). The invention also relates to a method for producing a cylinder liner of the aforementioned type.

Abstract: A liner retention system for a reciprocating pump having a piston and a piston rod operating in a cavity of a frame. The system includes a cylindrical liner for the piston and piston rod, the liner having a radially extending external shoulder. A liner clamp plate has a central opening receivable over the liner and a plurality of stud apertures. A plurality of studs extends from the frame, each stud terminating in a threaded end spaced from a module block. At least one compression sleeve has an inside diameter larger than an external diameter of the stud. Tensioner mechanism secures each stud to the liner clamp plate to thereby secure the cylindrical liner to the module block.

Abstract: A master cylinder housing including an outer shell having an open end and a closed end, a polymeric inner lining received within the outer shell, and a mounting flange extending from the open end of the outer shell.

Abstract: A hydraulic motor comprises a body and a piston able to slide in a reciprocating movement in a cylindrical housing of the body. A chamber (C1, C2) is formed on each side of the piston and hydraulic switching means are provided for feeding and evacuating the respective chambers (C1, C2), these switching means being able to adopt two stable positions. Control means (H) having elastic means for abruptly bringing about changes in the position of the switching means are included. There are triggering means (13, 15) able, at the end of the stroke of the piston (9), to bring about the change in position of the switching means (G). The piston (9) has a closed cross section and the switching means (G) are arranged in the body (1) of the machine, redially on the outside of the cylindrical housing (7) in which the piston (9) slides.

Abstract: A high pressure fluid jetting system generally includes a fluid cylinder pump, a drive assembly, a pressurized liquid supply and an applicator gun. The drive assembly includes a diesel or electric powered motor which drives a rotatable drive shaft. The drive shaft drives a triple plunger which are reciprocally driven. The plungers communicate fluid from the supply to the gun to selectively jet water from the gun at a pressure of approximately 50,000 psi and 10.0 gallons per minute.

Abstract: A pump includes a cylinder, a piston, a connecting rod, a plug, a nozzle and a fastener. The cylinder includes a first open end and a second open end. The piston is movable in the cylinder. The connecting rod includes a first end connected with the piston in the cylinder and a second end located outside the cylinder. The plug is fit in the first open end of the cylinder. The nozzle is mounted on the first open end of the cylinder. The fastener is used to fasten the nozzle and the plug to the cylinder.

Abstract: A double diaphragm pump including a pump housing, first and second pump diaphragms, an inlet manifold, an outlet manifold, and an air motor. The air motor includes a spool valve having a valve housing, an insert surrounded by the valve housing, and a spool. The valve housing and the insert cooperate to at least partially define a valve chamber, and the spool is slidably positioned within the valve chamber. The spool includes a seal engaging an inner surface of the insert and delimiting the valve chamber into valve subchambers. Movement of the spool within the valve chamber selectively communicates pressurized fluid to one of the diaphragms to move the associated diaphragm, thereby pumping fluid through the pump.

Abstract: A swash type compressor includes sleeves which are fixedly fitted in cylinder bores. The lengths of the sleeves in an axial direction are greater than the lengths of the cylinder bores in the axial direction. A sleeve end of each of the sleeves is flush with an end surface of a cylinder block defining the cylinder bores. The opposite sleeve end of the sleeve extends beyond the cylinder bore and away from the opposite end surface of the cylinder block.

Abstract: A drive cylinder comprising a cylinder barrel (3) extending between two cylinder heads (2a and 2b) and a plurality of ties (13) distributed about the outer periphery of the cylinder barrel (3) and bracing the cylinder heads (2a and 2b). Of these of ties at least one is constituted by a profile part (26) which extends in the peripheral direction (14) of the cylinder barrel (13) some distance along its outer periphery and whose profile provides means for the implementation of at least one additional function.

Abstract: A cylindrical bushing sleeve or another cast part, in particular a ring carrier for pistons, has a rough surface so that the surrounding cast material can cling to the cast part as required. The rough surface is created by producing the cast part with the aid of a lost mold provided with a particulate layer.

Abstract: Cylinder block (32) of an axial piston compressor (20), in particular for use in a vehicle air conditioner with CO2 as coolant, which comprises at least one, in particular several cylinder bores distributed about a periphery, each of which defines a cylinder face and accommodates a piston (8) consisting of piston shaft (8a) and piston neck (8b), wherein the piston neck (8b) outside the cylinder bore serves for coupling to a swash- and/or wobble-plate drive mechanism (29, 33) operatively connected to a rotatable drive shaft (1), by means of which the piston (8) is movable back and forth within the cylinder bore, between a top-dead-center point (OT) and a bottom-dead-center point (UT), and wherein the edge of the opening of the cylinder face on the drive-mechanism side comprises at least one recess (26d) that can be at least partially engaged by a transitional region (8c) disposed between the shaft (8a) and the neck (8b) of the piston, so that the cylinder face effective for the piston (8) is enlarged or elonga

Abstract: A cylinder liner system comprising a cylinder liner having an elongated tube, an inside surface, an outside surface, and a notch on a top side; a block having a bore for concentrically accepting the cylinder liner and a locking pin that engages the cylinder liner and the block.

Abstract: A pump includes a pump housing that defines an inlet and an outlet. Within the pump housing, there is a barrel that is adjacent to at least one reciprocating piston. A sleeve surrounds the annular outer surface of the piston and is movable. The temperature change within the pump is compensated for by making at least one of the sleeve and the barrel of a material with a lower coefficient of thermal expansion than the material of the piston. A clearance defined by an inner surface of the sleeve and the annular outer surface of the piston increases when the temperature is low and decreases when the temperature is high.

Abstract: A hydraulic system is provided for securing a cylinder liner to a pump module of a reciprocating pump, such as a mud pump. The hydraulic system includes a body attached to the pump module, a ram in sliding contact with the body and having a mating surface, preferably a radial shoulder, contacting the liner. Upon pressurization of fluid in a chamber defined by the body, the ram, and a pair of seals therebetween, the ram slides between a first position and a second position. The ram secures the liner to the module when in the first position and is removable in the second position. The system further includes a locking ring that engages the body, may be hand rotated upon pressurization, and mechanically holds the ram in the first position in the absence of hydraulic pressure. The hydraulic system is adapted to apply a precise axial securing force and to aid alignment of the liner.

Abstract: A cylinder liner system comprising a cylinder liner having an elongated tube, an inside surface an outside surface, and an notch on the top side; a block having a bore for concentrically accepting the cylinder liner and a locking pin that engages the cylinder liner and the block.

Abstract: In a cylinder liner of an internal combustion engine for casting into a light-metal crankcase to be cast, in order, during the casting in of the cylinder liner, to achieve as good a binding as possible of the cylinder liner to the surrounding casting material, the cylinder liner has on the outer circumference, in the region of the upper dead center of the piston rings of a piston guided in the liner, an activation layer which consists of a material which, due to the heat effect of the liquid casting material, connects metallically more rapidly to the latter than the liner material, and in that the cylinder liner has a rough surface on the outer circumference following the region of the upper dead center.

Abstract: The invention relates to a high-pressure device (1) having a cylindrical high-pressure vessel (3) and prestressing means in order to exert an axial pressure on the vessel. The vessel (3) can have been formed from a number of layers of composite material, such as glass, carbon or aramide fibers which are oriented in the peripheral direction and are embedded in a matrix of epoxy resin or polyurethane. By applying the axial prestress to the pressure vessel (3), the tangential stress is distributed more uniformly over the wall thickness of the high-pressure vessel (3), the stress decreasing at the inside of the wall and increasing at the outside thereof. As a result, the innermost fibers of a high-pressure vessel (3) made of composite material are subjected to appreciably less stress, which has a beneficial effect on the life of the high-pressure vessel (3), and all fibers of the wall are utilized effectively.

Abstract: Disclosed herein is an oilless air compressor having a cooling system with a drive unit operating a crankshaft disposed within a crankcase and to which is attached a pair of pistons movable within corresponding compression cylinders. A blower wheel is concentrically mounted to the crankshaft adjacent the exterior of the crankcase. Each compression cylinder includes a thermally conductive cylinder insert which a bore in which the corresponding piston rides. A thermally conductive heat sink having a plurality of annular cooling fins is cast integrally to the outer diameter of each cylinder insert and connected to the crankcase such that the compression cylinders and the crankcase are completely enclosed. Each cylinder insert is made of an aluminum alloy, preferably having a low silicon content and a high melting point so that it can be insert cast within the cooling fin and anodized without degrading the surface finish of its inner bore.

Abstract: An air damper for a movably supported structural part in automobiles comprises a hollow cylinder closed at one end thereof, a closure cap mounted on the other end of the cylinder, a piston slidably guided within the cylinder, an annular recess at the circumference of the piston, and an annular sealing ring in the recess. The block-like sealing ring is made of a thermoplastic elastomer coated with a layer which has the same static and sliding frictions with the inner wall of the cylinder and the bottom of the recess. A coil spring is placed between the closure cap and the piston. A piston rod of the piston has an elongated rib contacting the spring when the spring is in a relieved state.

Abstract: A master cylinder for vehicle braking systems includes a housing having a central cavity, at least one fluid supply inlet port, at least one pressure outlet port, and a flange at one end thereof. A piston actuation mechanism within the central cavity is moveable between a first position wherein the central cavity is in fluid communication with the fluid supply inlet and a second position where the central cavity is in fluid communication with the pressure outlet. A cup-shaped end cap is fastened to the housing flange in a fluid sealing relationship wherein the cup-shaped end cap receives at least a portion of the piston actuating mechanism therein and further retains the piston actuation mechanism in an operational configuration within the housing.

Abstract: Disclosed is a piston pump having a pump housing with a cylinder head comprised of a first plate and a second plate. The plates which rest against each other and are screwed to the pump housing, have a first conduit which carries low-pressure fuel and leads to a first check valve disposed between the two plates. The check valve communicates with a cylinder chamber of the radial piston pump. A second conduit carrying high-pressure fuel leads from this cylinder chamber to a second check valve, which is disposed between the first plate and the pump housing. Seals that are appropriate to the load, in fact low-pressure seals, are provided in the region of the cylinder head that is subjected to low pressure and high-pressure seals are provided in the region of the cylinder head that is subjected to high pressure.

Abstract: A hydraulic system is provided for securing a cylinder liner to a pump module of a reciprocating pump, such as a mud pump. The hydraulic system includes a body attached to the pump module, a ram in sliding contact with the body and having a mating surface, preferably a radial shoulder, contacting the liner. Upon pressurization of fluid in a chamber defined by the body, the ram, and a pair of seals therebetween, the ram slides between a first position and a second position. The ram secures the liner to the module when in the first position and is removable in the second position. The system further includes a locking ring that engages the body, may be hand rotated upon pressurization, and mechanically holds the ram in the first position in the absence of hydraulic pressure. The hydraulic system is adapted to apply a precise axial securing force and to aid alignment of the liner.

Abstract: The invention relates to a device (10) comprising a cylinder body (17) in an inner bore hole (22) in which a piston (21, 42) is mounted in such a way that it can slide axially, whereby the cylinder body (17) comprises at least one part in the front of the blind hole (17a) and one center part bearing a sealing joint, whereby both parts are fitted axially and consecutively from front to back and are interfixed in a sealed manner. Said inner bore hole comprises two front and rear sections which are substantially coaxial and concentric and are used to guide the piston (21,42) in an axially sliding manner. The invention is characterized in that both front (62) and rear (60) sections which are used to guide the piston (21,42) in a sliding manner belong to the center part (17B,64) of the cylinder body.