Abstract: A wind turbine main bearing realized to bear a shaft of a wind turbine, which shaft is caused to rotate by a number of blades connected to the shaft is disclosed. The wind turbine main bearing includes a fluid bearing with a plurality of bearing pads arranged about the shaft. Also disclosed is a wind turbine with a number of blades connected to a shaft and realized to rotate the shaft, which wind turbine includes as main bearing a wind turbine main bearing. Further described is a method of performing maintenance on a wind turbine, including the steps of halting a rotation of the shaft, operating a lifting arrangement to raise the shaft, and removing a bearing pad of the wind turbine main bearing from the bearing housing of the wind turbine main bearing.

Abstract: The present invention relates to methods for modifying automatic transmissions and gear trains. In particular, the instant invention relates to methods for modifying an automatic transmission gear train in order to improve resistance to deterioration. The modified gear grain of the instant invention comprises eight pinion gears assembled into one carrier utilizing a forward and a rear sun gear, a ring gear, a band drum and a one way roller clutch.

Abstract: A turbine nozzle may be repaired by severing the inner band from the vanes and outer band, which may then be discarded. A replacement nozzle is cast to include replacement vanes extending between a replacement outer band and an inner web, with the replacement outer band and vanes conforming with the original outer band and vanes. The new web is configured differently than the old inner band and includes a tie bar. The inner band is machined to form vane seats. The web is machined to form plinths atop the tie bar at each of the replacement vanes. The plinths and tie bar are assembled through the vane seats and bonded to the machined inner band to collectively form the repaired turbine nozzle.

Abstract: An article of manufacture has a body formed in part of a first metal alloy and in part of a second metal alloy, the second metal alloy having a thermal coefficient of expansion that is less than the thermal coefficient of expansion of the first metal alloy. A BOAS segment for a gas turbine engine is disclosed wherein the formation of cracks due to thermal mechanical fatigue in the body of the disclosed BOAS segment is minimized, if not eliminated, through a unique construction of the disclosed BOAS segment, whether original equipment manufacture or a repaired blade outer air seal. A method for manufacture of a BOAS segment and a method for modifying a BOAS segment are disclosed.

Abstract: A compressor case, and an associated method, repaired from damage to a segment of a stator ring hook. Two halves are engaged together at flange faces that define parting lines and that define a hollow interior, the ring hook being located at the interior, compressor case material having been removed at the stator ring hook location and a location of one of the flange faces to provide a space. A patch plug is slid into the space from the one flange face, the shape of the patch plug being complementary to a shape of the missing material space and inter-fitting therein, with an end of the patch plug being located at the one flange face to face an opposed half of the case with the two halves together. A fastener fastens the patch plug to the case and extending from the interior, through the patch plug, to the case.

Abstract: A compressor has a housing assembly and at least one rotor held by the housing assembly for rotation about a rotor axis. The rotor has a first face and a first housing element has a second face in facing spaced-apart relation to the first face of the rotor. One or more spacer elements are positioned from the first housing element. The spacer elements are machined. A coating is applied over the first surface around the one or more spacer elements.

Abstract: A turbomachine includes a compressor provided with a casing having an inner surface defining a flow path. At least one blade is rotatable within the flow path. The at least one blade includes a tip portion that is spaced from the inner surface. At least one patch ring segment is mounted to the inner surface of the casing. The at least one patch ring segment includes a body having a first end that extends to a second end through a surface portion. A first wall member extends from the first end and a second wall member extends from the second end. The first and second wall members include in-turned sections that define a C-shaped cross-section of the at least one patch ring segment.

Abstract: A cover is inserted into a housing of a fuel pump. Then, a housing-side engaging portion of the housing, which is located at a peripheral edge of an opening of the housing, is heated with a heating means. Thereafter, the housing-side engaging portion is swaged by a punch toward the cover to fix the cover to the housing.

Abstract: A method of repairing a turbomachine blisk having at least one damaged zone by build-up of metal in the damaged zone using a laser build-up welding machine is disclosed. The method includes preparing the damaged zone by machining the damaged zone to obtain a zone of defined profile to be repaired, build-up welding of a start-of-run test piece that includes the defined profile using the laser build-up welding machine, checking geometric and metallurgical quality of the test piece, and build-up welding the zone to be repaired of the blisk using the laser build-up welding machine.

Abstract: A replacement oil pump plate for attachment to an original equipment manufacture oil pump within a transfer case for elimination of mechanical wear by replacing the abrasive aluminum tabs formed on the oil pump with low-friction plastic tabs is disclosed. The present plastic tab design redistributes the surface-to-surface contact between the magnesium transfer case and the aluminum pump tabs away from the original wear points so that any necessary weld repairs to the transfer case will not be disturbed. The present replacement pump plate is provided in a kit format including a pump plate, machine screws, plastic tabs, and installation instructions. The present invention also describes a method of installing the pump plate kit on the original equipment manufacture oil pump subassembly.

Abstract: An air intake system for a gas turbine includes one or more coils in airflow communication with an inlet arrangement. Each coil is constructed and arranged to have a respective upstream face velocity that is intended to be within 20% of the other coils. Each coil utilizes a working fluid of a predetermined temperature range conveyed there through and a plurality of spaced fins. The fins are spaced apart to permit air to flow between adjacent fins as air flows through the coil. At least one of the coils has a number of fins per inch that is different from the number of fins per inch of the other coils. Alternatively, each individual coil has at least one section with fewer or greater numbers of fins per inch that the other sections of that coil.

Abstract: A modular vertical pump assembly has a motor, a coupling, a pump, a frame, and a base. The frame installs on the base around the pump, and supports of the frame hold a mount for the motor. The shaft from the motor extends through the mount, and the coupling installs between the motor shaft and a pump shaft. Preferably, the coupling uses an adapter and a stuffing box. Three supports fixedly attach to the mount and base, while one support is removable. To remove the pump for repair or replacement, the removable support detaches from the frame, and the pump detaches from the base and lifts from the frame's free side. Like the pump, the motor can be removed independently from the mount. In both cases, the coupling allows the pump's shaft to freely separate from the motor's shaft.

Abstract: A system and method for repairing turbine vane attachment systems in a turbine engine. In at least one embodiment, the invention may be directed to a system and method for repairing wear on a diaphragm hook fit configured to attach diaphragm airfoils, such as stationary turbine vanes, to a combustion turbine case. The restoration system may be formed from a carriage assembly having an assortment of material processing implements usable to build up material in the worn locations of the turbine vane attachment system to reestablish a diaphragm hook fit within the specified tolerances. The restoration system may be configured so that the restoration process may occur without removing a rotor assembly, which can reduce the repair time by about two weeks. Thus, use of the restoration system can result in a significant time and cost savings.

Abstract: A hydraulic pump can be remanufactured to save the investment in its components that are not seriously worn or failed. Some of the worn components, such as the pump barrel and yoke, can be salvaged by replacing or rebuilding the worn features. In particular, a worn internal spline on the pump barrel can be replaced by a spline insert that is threaded to the pump barrel and includes a new internal spline. A worn actuation tab on a yoke for contacting an actuating piston can be replaced by adding a new tab wear button.

Abstract: To protect the bearings, lubricant and seals of a refrigerant compressor, the compressor includes one or more inductors for mitigating a high frequency common mode current that produces a high frequency shaft voltage. Each inductor is a ring of magnetic material encircling three insulated cables that convey three-phase power from an adjustable frequency drive to the compressor's motor. Without the inductors, the high frequency shaft voltage can become damagingly high due to the length of a cast iron housing that can be particularly long if the housing contains both a motor and several centrifugal impellers. The high frequency shaft voltage is just one component of a composite adverse shaft voltage. Another component, known as an operationally induced shaft voltage, can be reduced by a grounding contact, so instead of using just an inductor or just a contact, both can be used to provide a total solution to the problem.

Abstract: A coupling for a pump connects a plunger to a plunger adaptor. The coupling provides a space between an end of the plunger and an end of the adaptor. Upon disconnecting the plunger from the adaptor, the space provides for removal of the plunger from and through a well of the pump.

Abstract: A steam turbine is provided that is configured for post-modification for operation in a carbon capture mode. The turbine includes a turbine rotor, a turbine casing and a plurality of turbine stages. In an initial configuration of the turbine, the turbine rotor and turbine casing are each longer, by respective lengths, than is necessary to accommodate the plurality of turbine stages. The lengths are sufficient to accommodate at least one further turbine stage at an exit of the turbine during the post-modification, such that after modification, the turbine operates with an increased expansion ratio and an increased volumetric flow rate at the exit.

Abstract: A linear actuator such as a hydraulic cylinder has linear position sensing apparatus. At least one magnet is provided in a recess in outer surface of the piston for generating a magnetic field that passes through the wall of the cylinder housing. A magnetic sensor arrangement determines the axial position of the piston relative to the housing and comprises at least a pair of magnetic sensor elements arranged at spaced apart locations along the external surface of the wall for sensing the strength of the magnetic field passing through the wall of the housing. The recess in the piston is axially positioned between the first and second end surfaces of the piston and the at least one magnet is disposed between axially spaced north and south pole pieces.

Abstract: A hydraulic pump can be remanufactured to save the investment in its components that are not seriously worn or failed. Some of the worn components, such as the pump barrel and yoke, can be salvaged by replacing or rebuilding the worn features. In particular, a worn internal spline on the pump barrel can be replaced by a spline insert that is threaded to the pump barrel and includes a new internal spline. A worn actuation tab on a yoke for contacting an actuating piston can be replaced by adding a new tab wear button.

Abstract: A mobile drip irrigation system that includes a supply pipe connected at one end to a liquid source and extending therefrom. At least one tower supports the supply pipe above the ground, and includes a driver for moving the tower and supply pipe in a desired direction. A plurality of ports are positioned along the supply pipe. The system includes a plurality of vertically oriented drop line assemblies. Each drop line assembly has an upper end connected to one of the plurality of ports, and a lower end spaced above the ground. A horizontal liquid distribution system is fluidly connected to the plurality of drop line assemblies to allow a horizontally uniformly spaced drip of the liquid at a desired distance from the ground.

Abstract: The static seal (30) includes a rotary seal body (32) comprising an annular base portion (34) which is drivingly mountable on a rotary component such as a shaft and an annular cantilever portion (40) connected at one end to the base portion (34). The seal (30) 5 further includes a rotary seal face (48) and circumferential weights (44) connected to the cantilever portion (40). The seal is configured to dilate under centrifugal force to provide a running clearance between the rotary seal face and a complementary static seal face with which the rotary seal face is in contact when the rotary seal body (28) is stationary. The rotary seal body is further configured so as to facilitate the breaking up of slurry which may set around the seal when the pump (10) of which the seal forms part is inoperative.

Abstract: An insertion/extraction system and method for a compressor casing and a compressor bundle. The system includes a cradle extending from a first axial end of the compressor casing and configured to provide support for the compressor bundle during insertion, and an extension assembly coupled to a first axial end of the compressor bundle and extending therefrom into the compressor casing during insertion of the compressor bundle into the compressor casing, during extraction of the compressor bundle from the compressor casing, or both. The system further includes a support member that engages the extension assembly and the compressor casing to support the first axial end of the compressor bundle via the extension assembly, the support member configured to allow relative movement between the support member and the extension assembly during insertion of the compressor bundle into the compressor casing, extraction of the compressor bundle from the compressor casing, or both.

Abstract: A vacuum pump having components that are subject to wear may be adjusted to compensate for the wear. In some instances, a vacuum pump may include a housing and an impeller disposed at least partially within the housing. A gap between the housing and the impeller may be adjustable to compensate for wear. In some cases, the housing may include a ring that may be moved to adjust a tolerance (or gap) between the ring and the impeller. In some instances, the ring may be rotated to adjust this gap. In other instances, the ring may be translated to adjust the tolerance.

Abstract: The present concepts relate to turbocharger exhaust arrangements. One example involves a system that includes an internal combustion engine configured with a turbocharger. The system also includes an exhaust arrangement comprising a post-turbocharger (PT) exhaust pipe connected to the turbocharger and positioned proximate to the internal combustion engine, the PT exhaust pipe extending away from the turbocharger along the internal combustion engine. The PT exhaust pipe includes a first portion extending above at least one part of a set of header exhaust pipes connecting the internal combustion engine with the turbocharger. The PT exhaust pipe also includes one or more additional connected and contiguous portions extending below at least one other part of the set of header exhaust pipes.

Abstract: The invention relates to a method for producing and repairing a part comprising at least two joined metal components, especially components of a gas turbine. In said method, corresponding joining surfaces of the components are joined together and connected by means of a pressure welding process, a machining allowance in the area of a joining zone of the two joining surfaces is upset during the joining process, and once the two components have been joined together, the machining allowance is machined by means of a precise electrochemical machining (PECM) process until a predefined final contour of the part has been obtained. The invention further relates to a gas turbine part obtained by means of the disclosed method.

Abstract: A method for repairing a sealing segment of a gas turbine is provided. The sealing segment includes a radially outer holding portion for a radially inner abradable portion. The method includes the steps of providing a sealing segment to be repaired; removing a damaged, radially inner abradable portion of the sealing segment along a circumferentially extending parting plane, such that the abradable portion is completely removed from the holding portion; making a replacement part for the separated abradable portion of the sealing segment; and joining the replacement part to the holding portion of the sealing segment.

Abstract: A carrier that holds a plunger for a reciprocating pump during maintenance. Maintenance of the pump typically includes repacking of the packing that surrounds the plunger and revalving of the pump's inlet and outlet valve. To allow repacking or revalving, the pump is disassembled and the plunger is removed. The carrier mates with the pump to hold and support weight of the plunger during disassembly, allowing one person to perform pump revalving and repacking.

Abstract: A reciprocating pump has a driven crankshaft and a connecting rod having an aft end rotatably mounted to the crankshaft. The pump has a stationarily mounted crosshead case in which a crosshead assembly strokes. The crosshead assembly has first and second crosshead members. A retainer pivotally joins the forward end of the connecting rod to the first crosshead member. The second crosshead member has a partially cylindrical recess containing a bushing. The forward end of the connecting rod is in pivotal engagement with the bushing. The second crosshead member is releasably secured to the first crosshead member to allow removal of the second crosshead member and the bushing from the crosshead case without detaching the forward end of the connecting rod from the first crosshead member.

Abstract: A compressor has a diffuser section with one or more detachable wall portions that define a diffuser surface. The wall portions may be detachably connected to an intermediate portion of the compressor housing between the inlet and outlet and/or to the bearing housing of a turbocharger to which the compressor housing is connected. The diffuser wall portions can be easily detached once the compressor housing is removed so as to allow cleaning of deposits or simple replacement. This provides for easy servicing to avoid the compressor performance being compromised by a built up of deposits and particulates on the diffuser surfaces that is a particular problem in turbochargers that receive recirculated crank case ventilation gases from the engine.

Abstract: A method of forming an interstage seal including removing a diaphragm seal box (14) from a gas turbine compressor assembly (10) and removing a labyrinth sealing member (12) from the diaphragm seal box (14). An abradable material layer (34) may be deposited on the diaphragm seal box (14). A spray gun may be mounted in relation to an engine disk (16) of the gas turbine compressor assembly (10) for cold-spraying a quantity of particles toward the engine disk (16). The particles may be sprayed at a velocity sufficiently high to cause at least a portion of the quantity of particles to adhere to the engine disk (16). The spray gun may be controlled to deposit a quantity of particles on the compressor disk (16) to form a geometry (32) that will abrade the abradable material layer (34) during operation of the gas turbine compressor assembly (10). The geometry (32) abrading the abradable material layer (34) forms an interstage seal.

Abstract: A surface pump assembly having a thrust chamber with a telescoping shaft. In some embodiments, the surface pump assembly has a pump with a pump shaft, a thrust chamber with a telescoping shaft extending therein, the telescoping shaft extendable to engage the pump shaft and retractable to disengage the pump shaft, and a motor coupled to the telescoping shaft and operable to rotate the telescoping shaft. In some embodiments, the telescoping shaft has a rotatable shaft member, an adjusting nut threadably disposed thereabout, wherein the adjusting nut is moveable axially relative to the shaft member by rotation, and a first sleeve translatably disposed about the shaft member.

Abstract: A compressor case, and an associated method, repaired from damage to a segment of a stator ring hook. Two halves are engaged together at flange faces that define parting lines and that define a hollow interior, the ring hook being located at the interior, compressor case material having been removed at the stator ring hook location and a location of one of the flange faces to provide a space. A patch plug is slid into the space from the one flange face, the shape of the patch plug being complementary to a shape of the missing material space and inter-fitting therein, with an end of the patch plug being located at the one flange face to face an opposed half of the case with the two halves together. A fastener fastens the patch plug to the case and extending from the interior, through the patch plug, to the case.

Abstract: A pump housing assembly which includes a pump casing and a liner, where the pump casing includes at least two parts which are adapted to be connected together in an assembled position with the pump casing having opposed front and rear sides and a common junction region which is disposed within one or more planes which pass through the front and rear sides of the assembled pump casing, the liner being formed in one piece and having sealing portions that are activated to provide a seal between the liner and the pump casing.

Abstract: A method and apparatus for repairing and/or preventatively maintaining a jet pump restrainer assembly used in a Boiling Water Reactor (BWR), the repair including attaching a bearing plate or plates to a horizontal surface of a jet pump restrainer assembly bracket, the bearing plate or plates acting to supplement and/or replace an existing contact surface between a mixer wedge and the jet pump restrainer assembly bracket of a jet pump restrainer assembly.

Abstract: The invention relates to a method of calibrating a connecting rod arrangement comprising a crankshaft eye and a connecting rod eye. In order to achieve the best possible parallelism between the connecting rod eye and the crankshaft eye a controlled energy input occurs in at least one predefined surface area of the connecting rod, so that outside a neutral axis a local structural change and thus a tension in the connecting rod occurs.

Abstract: The present invention provides an apparatus and method for an adaptive machining and weld repair process useful for repairing airfoils, particularly damage to an airfoil leading edge and tip. The process first machines away damaged portions of the airfoil. Next, the actual profile of the airfoil subsequent to the removal of the damaged material is measured using a Coordinate Measuring Machine. The data is then used to generate a deformation profile. Filler material is then added to the machined area using the data of the deformation profile to produce an airfoil that approximates the ideal shape of a restored airfoil. At this point, the actual profile of the welded airfoil is measured using the Coordinate Measuring Machine. The data is then used to generate a deformation profile and the airfoil is machined using the date of the deformation profile to produce that shape. The adaptive technology minimizes the amount of stock on material that needs to be removed by hand.

Abstract: Stator blade counts of an upper compressor casing for adjacent stages S0 and S1 are changed in the field to provide additional stator vanes and hence an increased vane count. Particularly, the upper casing half of the compressor is removed from the lower casing half. The original stator vanes on opposite axial sides of the first stage buckets are removed from the upper casing half and replaced by an additional sets of stator vanes providing a non-uniform vane spacing as between the upper and lower halves of the compressor as well as between axially adjacent stages S0 and S1. The unequal vane counts reduce the vibratory response of the rotating blades between stages S0 and S1.

Abstract: A compressor capable of surely preventing leakage of a refrigerant gas from a connection portion between an airtight container and a pipe to the outside at low cost is provided. The compressor comprises an airtight container to which a refrigerant introduction pipe is connected, and a compression element received in the airtight container to discharge the refrigerant into the same. The refrigerant introduction pipe has a cylindrical pipe main body, and a jaw-like flange portion formed in a tip of the pipe main body. A cylindrical connection sleeve is disposed between the refrigerant introduction pipe and the airtight container. A first bolt is disposed to connect the connection sleeve to the airtight container, and a second bolt is disposed to connect the connection sleeve to the flange portion of the refrigerant introduction pipe. The flange portion of the refrigerant introduction pipe hides the first bolt.

Abstract: A maintenance method of a gas turbine unit, having a first stator element provided with first connecting holes contemplates replacing a second stator element, provided with second connecting holes and connected to the first stator element by means of coupling pins insertable into the first and the second connecting holes, with a third spare stator element provided with third connecting holes; and coupling the first stator element to the third spare stator element by means of eccentric coupling pins and eccentric bushes, each of which is selectively insertable in the first and the third connecting holes.

Abstract: A method of repairing a one-piece annular combustor of a gas turbine engine includes cutting through the combustor liner to separate the combustor into two pieces, repairing the combustor as desired, and then closing the combustor by using a make-up ring, which may be welded in place between the two pieces of the combustor. The make-up ring may be provided with an axial length selected such that an overall length of the combustor after the repair process is substantially equal to an initial overall length of the combustor before the repair.

Abstract: An apparatus and method adapted to facilitate removal of stator vane segments in a slot of a casing of a rotating machine with stator vanes segments and rotating blades. The apparatus includes a compression device adapted to apply a pushing force on a rear surface of a stator vane segment, a clearing element adapted to free adhesion materials holding the stator vane segment to the dovetailed slot of the lower casing of the rotating machine with stator vanes segments and rotating blades, and a tension device adapted to apply a pulling force on a forward pail of the stator vane segment.

Abstract: The air cycle machine insert and method of repair provides an economical repair of the turbine housing section of an air cycle machine, rather than scrapping the component and replacing with a new section. The toroid shaped insert or liner has a U-shaped cross section, configured to fit closely within the turbine air passage of the air cycle machine. A throat insert is also provided. The existing throat flange extending outwardly over the turbine air passage is removed for installation of the insert. High temperature silicone sealant is preferably placed between the wall of the turbine air passage and the liner, after machining the air passage wall to remove irregularities. The liner is then installed and mechanically secured with one or more rivets, the throat insert is installed to replace the previously removed throat flange, and the repaired turbine housing reassembled with the air cycle machine to complete the repair.

Abstract: A method of repairing a turbine exhaust case strut heat shield vane includes removing a damaged portion of the vane, solution heat treating the vane, attaching a replacement section to the vane, and relieving local stresses in an attachment area between the replacement section and the vane.

Abstract: A starter for moving a movable portion of an engine to start the engine includes a gear housing, a gear assembly within the gear housing, an output member at a first end of the gear assembly adapted to operably couple to the movable portion of the engine, a motor housing, and a rotor rotatably mounted within the motor housing. The rotor has a shaft portion and a vane portion that are an integral, unitary piece. The shaft portion has splines for mating with the gear assembly. The splines prevent relative rotational movement between the rotor and the gear assembly and permit relative axial movement. The rotor is formed from aluminum and at least a portion of the rotor includes an anodized coating.

Abstract: A pump includes a housing and a shaft rotatable about an axis. The shaft has a shaft diameter and has a portion disposed within the housing. A plurality of retractable vanes is coupled to the shaft and each vane includes a first end that contacts the housing. A seal element is positioned to define a seal between the shaft and the housing. The seal element includes a first bushing, a second bushing, and a dry seal assembly including a wiper that defines a diameter that is smaller than the shaft diameter.

Abstract: A method of refurbishing a seal land on a transition piece of a turbomachine includes applying a wear strip to a wall surface of the seal land, and covering the wear strip with a slot protector.

Abstract: Nickel-based superalloys, repaired turbine components, and methods repairing turbine components are provided. In an embodiment, by way of example only, a nickel-based superalloy consists essentially of, by weight percent, chromium in a range of from about 7.0 percent to about 8.0 percent, cobalt in a range of from about 5.5 percent to about 6.5 percent, tungsten in a range of from about 3.0 percent to about 4.0 percent, rhenium in a range of from about 2.2 percent to about 2.8 percent, aluminum in a range of from about 7.5 percent to about 8.5 percent, tantalum in a range of from about 5.5 percent to about 6.5 percent, silicon in a range of from about 0.2 percent to about 0.5 percent, hafnium in a range of from about 0.15 percent to about 0.25 percent, and a balance of nickel.

Abstract: Rotary lobe pump and circumferential piston pump designs are disclosed where the drive and driven shafts are detachably connected to their respective rotors. The rotors are disposed in a pump or rotor casing, which is sandwiched between a head cover and a gearbox. The drive and driven shafts pass through mechanical seal assemblies, which are sandwiched between the first and second rotors and the gear box respectively. The seal assemblies can be serviced or replaced by simply removing the head cover and removing the rotors from the drive and driven shafts. The pump casing does not need to be removed to replace or service the seal assemblies. Further, the capacities of the disclosed rotary lobe and circumferential piston pumps can be modified without changing the gearboxes or shaft length. To modify a pump capacity, all that needs to be changed are the rotors, the pump or rotor casing and, in some designs, the head cover or cover plate.

Abstract: A compressor (20) has an unloading slide valve (100). The valve has a valve element (102) having a range between a first condition and a second condition, the second condition being unloaded relative to the first condition. A piston (124) is in a cylinder (128) and mechanically coupled to the valve element. A control valve (40; 42) is coupled to a headspace (138) of the cylinder to selectively expose the headspace to a fluid source (144), pressure of fluid in the headspace producing a force on the piston and valve element in a direction from the second condition toward the first condition. The compressor includes means (190, 192; 210; 220) for relieving excess pressure in the headspace.

Abstract: A compressor (20) has an unloading slide valve (100). The valve has a valve element (102) having a range between a first condition and a second condition, the second condition being unloaded relative to the first condition. A first surface (200) of the valve element (102) is in sliding engagement with a second surface (202) of the housing (22) during movement between the first and second conditions. The valve element is coupled to an actuating piston (124). The compressor includes a linear bearing (132) guiding a piston shaft (122).