WO2016202445A1

WO2016202445A1 - Axial piston machine

Info

Publication number: WO2016202445A1
Application number: PCT/EP2016/000975
Authority: WO
Inventors: Robert Adler; Markus Stephan; Markus Rasch; Christoph Nagl
Original assignee: Linde Aktiengesellschaft
Priority date: 2015-06-16
Filing date: 2016-06-11
Publication date: 2016-12-22
Also published as: DE102015007734A1

Abstract

The invention relates to an axial piston machine for compressing a gas, comprising a suction opening (110) and a discharge opening (120) for gas. In a conveying path for the gas between the suction opening (110) and the discharge opening (120), at least two suction chambers (130, 131, 132) are provided and an associated pressure chamber (140, 141, 142) is provided for each suction chamber (130, 131, 132). The suction chambers (130, 131, 132) and the pressure chambers (140, 141, 142) are arranged in alternation along the conveying path, beginning with a suction chamber (130) connected to the suction opening (110). The last pressure chamber (142) along the conveying path is connected to the discharge opening (120), and the remaining pressure chambers (140, 141) are each connected to the suction chamber (131, 132) that is next in the conveying path.

Description

description

axial piston

The invention relates to an axial piston machine for compressing gas. State of the art

Devices for compressing gases are known. For example. can do this

Reciprocating compressors, rotary compressors or ionic compressors are used. For higher compression ratios can, for example, a multi-stage construction of

Compression devices are used. However, individual stages usually have to be separated from one another by valves or slide controls. This leads to a complex and error-prone construction.

Furthermore, axial piston machines or pumps are known which are used to generate pressure in liquids. However, a compression of gases is hereby usually not or only possible with difficulty, since axial piston machines permit no optimization of a dead volume due to the design, which is used to promote

Liquids, however, is not relevant. A dead space-related re-expansion in the compression of gases thereby reduces the capacity of the compacting device. This is especially significant for particularly high compression ratios.

It is therefore desirable to provide a means for effectively and simply compressing gases.

Disclosure of the invention

This object is achieved by an axial piston machine having the features of patent claim 1.

Advantages of the invention An axial piston machine according to the invention serves for compressing a gas and has a suction opening and a discharge opening for gas. In this case, at least two suction chambers and to each suction chamber an associated pressure chamber are provided in a conveying path for the gas between the suction port and the discharge port in the axial piston. The suction chambers and the pressure chambers are each alternating and starting with a suction chamber, which with the

Intake port is in communication, arranged along the conveying path. In this case, the last pressure chamber along the conveying path with the ejection opening and the other pressure chambers are each in communication with the suction chamber following in the conveying path.

In this way, a multi-stage compression is possible with an axial piston machine. Gas can be sucked in via the intake opening and a first suction chamber and compressed in the subsequent pressure chamber. The already pre-compressed gas in this way can now be sucked into a further suction chamber and further compressed according to the piston movement, as is customary in an axial piston machine, in the subsequent pressure chamber. Depending on the number of suction and pressure chambers thus a multi-stage compression by means of a

Axial piston machine possible. A dead volume corresponding to a volume of a space when a piston is at its top dead center, i. if the space has the smallest possible volume, significantly less weight is involved in a multi-stage compression than in a single-stage compression, since a re-expansion of the gas due to the lower compression ratios has less effect. Thus, a much more effective compression of gas is possible with an axial piston according to the invention than with a conventional

Axial piston. A preferred number of suction chambers or pressure chambers is three. However, there are only two or four or more suction or

Pressure chambers possible, for example, depending on the size and more accurate design of the

Axial piston. However, the exact ratios of the individual compression stages to each other can be designed as needed.

Preferably, the axial piston machine on a valve disc, which has the suction chambers and the pressure chambers. In particular, the connection between a pressure chamber and a subsequent suction chamber is designed in each case as a channel in the valve disk. In the case of a valve disk, this is an in the rule fixed, ie non-rotating component of the axial piston machine. This is a particularly simple way to provide the suction and pressure chambers given. The channels can be executed, for example, as simple holes between the corresponding spaces.

Advantageously, the suction chambers and the pressure chambers are each formed as arcuate recesses in the valve disc. Due to the generally circular cross section of the axial piston machine so that a simple and effective arrangement of the suction and pressure chambers is given. In particular, the suction and pressure chambers can be formed as depressions in the valve disc, so that gas that is conveyed in these rooms, with pistons, which usually move up and down over the valve disc, can be promoted.

It is advantageous if each suction chamber and the subsequent in the conveying path

Pressure chamber in each case with the same radial distance to a rotation axis of the

Axial piston machine are provided in the valve disc. This allows a particularly simple design of the valve disc. In particular, the pistons that suck gas into a suction chamber can then compress the gas in the associated pressure chamber at the same radial distance. In addition, a particularly effective distribution of the suction and pressure chambers in the valve disc is possible.

Preferably, a subsequent in the conveying path to another suction chamber

Suction chamber provided radially relative to a rotational axis of the axial piston within this other suction chamber. Together with the same radial

Arrangement of a suction chamber with the associated, i. subsequent pressure chamber, this arrangement also applies to the pressure chambers. In this way, the individual compaction levels, i. in each case a suction chamber and the subsequent pressure chamber, are arranged from outside to inside. In this way, the volumes of the respective suction or pressure chambers with increasing compression level lower, since the space on the valve disc is smaller inside than outside. Although the step pressure ratios of the volume ratios of the cylinder or the

Volumes, which are limited by the piston in the cylinders, are determined, influenced by the suction and pressure chambers DC link volume also affects the pressure levels step. Thus, the compression and thus Volume reduction of the gas with increasing compression level be taken into account.

Advantageously, the axial piston machine has a distributor disk in which a plurality of pistons of the axial piston machine can be guided. In such a

Distributor disc is usually a rotating component of the axial piston machine, in which the pistons are guided in corresponding guide channels or recesses. The distributor disc rests on the valve disc, so that through the suction and pressure chambers of the valve disc and the piston and the corresponding guide channels a conveying path for the gas through the

Axial piston machine is formed when the distributor disc rotates. In this way, a particularly simple axial piston machine, in particular without moving valves are provided, whereby, for example, a maintenance of

Axial piston machine is reduced.

It is advantageous if each piston is associated with a suction chamber and a pressure chamber following this suction chamber in the conveying path, so that with this piston and a guide channel associated with the corresponding piston in the

Distributor disc only the associated suction chamber and the associated pressure chamber, a space for gas is formed. This ensures that gas can not flow back and forth between suction or pressure chambers of different compression stages, which would make compaction less effective.

Preferably, a number of pistons, which are associated with a suction chamber and a pressure chamber, for two successive in the conveying path suction chambers is equal to or decreases. Thus, the on the valve disc inwardly with respect to their tangential length shorter suction or pressure chambers are taken into account. In the case of three compression stages, i. three suction and three pressure chambers, and for example nine pistons, for example, four pistons of the first compression stage, three pistons of the second compression stage and two pistons of the third compression stage can be assigned. This allows a particularly effective compaction.

Advantageously, guide channels of two adjacent pistons, which are respectively assigned to the last suction chamber and the last pressure chamber in the conveying path, communicate with one another. In the case of two pistons for the last compression stage So they can form a common space for gas. This is advantageous, for example, when the innermost suction and pressure chambers are located within the pistons or their guide channels. The axial piston machines are preferably used for cryogenic compression or for ionic compression.

Sliding surfaces of the axial piston machine, in particular the sliding surfaces of the pistons and / or their guide channels are preferably made of technical ceramic or coated with technical ceramic.

The axial piston machine is used for the compression of gases. In particular, the axial piston machine is used for the compression of carbon dioxide, hydrogen, methane, natural gas, helium or nitrogen.

The axial piston machines are preferably operated at speeds of 100 to 2000 rpm (revolutions per minute) and more preferably at 1300-1800 rpm.

The speed of the axial piston machine is varied in particular depending on the running time. In a preferred embodiment, the speed is 100 to 800 rpm during the first 5% of the run time, 800-1300 rpm during the following 10% of the run time, 1300-1800 rpm for 80% of the run time, and 1800-2000 RPM up to 5% of the running time The axial piston machine for compressing gas is preferably operated at temperatures of -253 to 150 ° C. By the axial piston machine, the gas can preferably be compressed to pressures between 0.1 bar and 1000 bar.

The temperatures and pressures depend on the gas to be compressed. In the following embodiments, preferred operating parameters for compressing various gases with the axial piston engine will be described. The gases may also be moist and / or contaminated gases or gas mixtures.

Carbon dioxide: The inlet temperature (temperature before compression) of the carbon dioxide is preferably between -60 ° C and 120 ° C, especially 1 to 80 ° C. The

Starting temperature (temperature after compression) of the carbon dioxide is preferably between 40 and 150 ° C, in particular between 60 and 100 ° C. The inlet pressure (pressure before compression) of the carbon dioxide is preferably 0.1 bar to 10 bar, in particular 0.2 to 4 bar. The initial pressure (pressure after compression) of the carbon dioxide is preferably between 5 and 100 bar, in particular 20 to 60 bar. The volume flow is preferably 0.5 Nm ³ / h to 50 Nm ³ / h, in particular 1 Nm ³ / h to 8 Nm ³ / h.

Hydrogen:

The inlet temperature (temperature before compression) of the hydrogen is preferably between -253 ° C and 80 ° C, especially -253 ° C to -80 ° C when used as a cryogenic compressor or in particular -20 ° C to 80 ° C in the Use as ionic compressor. The starting temperature (temperature after compression) of the hydrogen is preferably between -250 and 150 ° C, in particular between -60 and 80 ° C. The inlet pressure (pressure before compression) of the hydrogen is preferably 0.8 bar to 40 bar, in particular 2.5 to 30 bar. The outlet pressure (pressure after compression) of the hydrogen is preferably between 10 and 1000 bar, in particular 500 to 1000 bar. The volume flow is preferably 0.5 Nm ³ / h to 500 Nm ³ / h, in particular at 50 Nm ³ / h to 350 Nm ³ / h.

Methane or natural gas:

The inlet temperature (temperature before compression) of the methane or natural gas is preferably between -182 ° C and 80 ° C, especially -182 ° C to -40 ° C when used as a cryogenic compressor or more particularly -20 ° C to 80 ° C. when used as ionic compressor. The starting temperature (temperature after compression) of the methane or natural gas is preferably between -180 and 150 ° C, in particular between -60 and 80 ° C. The inlet pressure (pressure before compression) of the methane or natural gas is preferably 0.8 bar to 30 bar, in particular 1.5 to 20 bar. The outlet pressure (pressure after compression) of the methane or natural gas is preferably between 10 and 650 bar, in particular 300 to 600 bar. The volume flow is preferably 0.5 Nm ³ / h to 1000 Nm ³ / h, in particular 5 Nm ³ / h to 350 Nm ³ / h. Helium:

The inlet temperature (temperature before compression) of the helium is preferably between -269 ° C and 80 ° C, in particular -269 ° C to -80 ° C when used as a cryogenic compressor or especially -20 ° C to 80 ° C in the Use as ionic compressor. The starting temperature (temperature after compression) of the helium is preferably between -269 and 150 ° C, in particular between -60 and 80 ° C. The inlet pressure (pressure before compression) of the helium is preferably 0.8 bar to 40 bar, in particular 2.5 to 20 bar. The initial pressure (pressure after compression) of the helium is preferably between 10 and

1000 bar, in particular 200 to 600 bar. The volume flow is preferably 0.5 Nm ³ / h to 600 Nm ³ / h, in particular at 50 Nm ³ / h to 400 Nm ³ / h.

Nitrogen:

The inlet temperature (temperature before compression) of the nitrogen is preferably between -196 ° C and 80 ° C, in particular -196 ° C to -40 ° C when used as a cryogenic compressor or in particular -20 ° C to 80 ° C in the Use as ionic compressor. The starting temperature (temperature after compression) of the nitrogen is preferably between -195 and 150 ° C,

especially between -60 and 80 ° C. The inlet pressure (pressure before compression) of the nitrogen is preferably 0.8 bar to 30 bar, in particular 1.5 to 17 bar. The outlet pressure (pressure after compression) of the nitrogen is preferably between 10 and 650 bar, in particular 200 to 400 bar. The volume flow is preferably 0.5 Nm ³ / h to 500 Nm ³ / h, in particular at 5 Nm ³ / h to 350 Nm ³ / h.

Brief description of the drawings

FIG. 1 shows a schematic and side view of an inventive device

Axial piston machine in a preferred embodiment.

FIG. 2 shows schematically and in plan view a valve disc of FIG

axial piston machine according to the invention in a preferred

Embodiment. Figure 3 shows schematically and in plan view a distributor disc of an axial piston machine according to the invention in a preferred

Embodiment. Figure 4 shows schematically and in cross section an inventive

Axial piston machine in a preferred embodiment.

Embodiment of the Invention FIG. 1 is a schematic and side view of an invention

Axial piston machine 100 shown in a preferred embodiment. The axial piston machine 100 in this case has a valve disk 101 and a distributor disk 102, wherein the distributor disk 102 rests against the valve disk 101. The

Valve disc and the distributor disc are shown and described in more detail in the following figures.

In FIG. 2, a valve disk 101 is shown diagrammatically and in plan view

axial piston machine 100 according to the invention shown in a preferred embodiment.

The valve disk 101 has an intake opening 110 which is connected to a suction chamber 130 via a suction channel 11 1, which in the present case is shown only in broken lines and runs deeper than the cross-sectional plane. The suction chamber 130 is arcuate or kidney-shaped, as is customary for axial piston pumps. The suction chamber 130 is in this case with respect to that shown in FIG

Cross-sectional view located higher than the suction channel 110. The suction chamber 130 may be formed as a recess in the valve disc 101.

Furthermore, the valve disc 101 has two further suction chambers 131 and 132, which are similar to the suction chamber 130, but are offset in the direction of the center of the distributor disc 101 and accordingly also have a smaller tangential length. In addition, the suction chambers 131 and 132 are not connected to the suction port 1 10 or the suction channel 1 11 in connection. Furthermore, the axial piston machine 100 has an ejection opening 120, which is connected to a pressure chamber 142 via a pressure channel 121, which in the present case is likewise shown only by dashed lines and runs deeper than the cross-sectional plane. In addition, two further pressure chambers 140 and 141 are provided, which are not connected to the discharge port 120 or the pressure channel 121. The pressure chambers are, similar to the suction chambers, arc-shaped or kidney-shaped. The pressure chambers, as well as the suction chambers, as a recess in the

Valve disk be formed. The suction chambers 130, 131 and 132 and the pressure chambers 140, 141 and 142 are at least approximately at the same height with respect to the cross-sectional plane. Likewise, the suction channel 1 10 and the pressure channel 120 are approximately at the same height. The suction chambers and the pressure chambers are open to the top of the valve disc 101, which rests against the distributor disc.

Furthermore, in each case a channel 180 or 181 is provided between the pressure chamber 140 and the suction chamber 131 and between the pressure chamber 141 and the suction chamber 132, which connects the corresponding spaces. In FIG. 3, a distribution disk 102 is shown schematically and in plan view

axial piston machine 100 according to the invention shown in a preferred embodiment. The illustrated plan view corresponds to the side of the distributor disc 102, which rests against the side of the valve disc 01 shown in FIG. 2, when the two discs abut one another, as shown in FIG.

The distributor plate 102 has a plurality of pistons and corresponding guide channels in which the pistons are movably mounted on. The pistons can thereby rotate about an axis of rotation of the axial piston machine 100 or of the distributor disk 102, which in the present case extends perpendicularly through the center of the view shown. The pistons run circular over the suction chambers and the pressure chambers. By way of example, nine pistons are shown as dashed circles, four of which are designated by the reference numeral 160, three by the reference numeral 161 and two by the

Reference numeral 162 are designated. Furthermore, 102 of the piston associated working channels are provided in the distributor disc. In this case, the pistons 160, the working channels 170 and the pistons 161, the working channels 171 assigned. The two pistons 162 are associated with a common working channel 172, which is connected via two dashed channels in the distributor plate 102 with the two pistons 162.

The four working channels 170 are arranged in the distributor disc and with respect to the pistons 160 such that a space can be formed between the pistons 160, the associated guide channels and the suction chamber 130 or the pressure chamber 140 via the working channels 170. In particular, therefore, no connection between a

Guide channel of the piston 160 and the other suction chambers 31 and 132 and pressure chambers 141 and 142 are produced.

The three working channels 171 are arranged in the distributor disc and with respect to the pistons 161 so that a space can be formed between the pistons 161, the associated guide channels and the suction chamber 131 or the pressure chamber 141 via the working channels 171. In particular, therefore, no connection between a guide channel of the piston 161 and the other suction chambers 130 and 132 or pressure chambers 140 and 142 can be produced.

The working channel 172 is arranged in the distributor disc and with respect to the piston 162 so that a space between the piston 162, the associated guide channels and the suction chamber 132 and the pressure chamber 142 can be formed via the working channel 172. In particular, therefore, no connection between a guide channel of the piston 162 and the other suction chambers 130 and 131 or pressure chambers 140 and 141 can be produced.

In Figure 4 is a schematic and cross-section of an inventive

Axial piston machine 100 shown in a preferred embodiment. In this case, the valve disk 101 and the distributor disk 102 are juxtaposed with the surfaces shown in FIGS. 2 and 3, respectively. In this case, instead of the pistons 160, 161 and 162, the associated guide channels 160 ', 161' and 162 'are now shown.

It can be seen that the pistons 160 or the guide channels 160 'can only be connected to the pressure chamber 140 or the suction chamber 130. The same applies to the Piston 161 and guide channels 161 ', the pressure chamber 141 and the suction chamber 131. The pressure chamber 142 and the suction chamber 132 are not visible in the view shown, since they are covered by the distributor plate 102. As usual for an axial piston machine, the height of the piston varies over the valve disc. In the exemplary embodiment shown, a piston reaches its top dead center in the region of the valve disk by providing the channels 180 and 181 (see FIG. 2), ie at this point there is a space which the piston with the valve disk (and a guide channel in the distributor disk ), minimal. This minimal space is also referred to as dead volume. Its bottom dead center then reaches the piston after a rotation through 180 °, ie there the piston includes a maximum space with the valve disc 101 a.

If the axial piston machine 100 is now used for compressing gas, the pistons, for example by means of an electric motor, are rotated about the axis of rotation in the direction denoted by R. The space formed by the pistons 160 with the valve disk 101 thus increases from the upper end of the suction space 130 (with respect to FIG. 2) to the lower end. Thus, the gas, for example carbon dioxide, is sucked into the suction chamber 130 via the suction opening 120 and the suction channel 11.

By a further rotation, the piston 160 reach the pressure chamber 140. The space formed by the piston 160 with the valve disc 101 thereby decreases from the lower end (with respect to FIG. 2) of the pressure chamber 140 to the upper end, whereby the gas is compressed. This is therefore a first

Compression stage. The gas then passes into the channel 180, the

Pressure chamber 140 connects to the suction chamber 131.

By a further rotation of the distributor disc 102, the pistons 161 are now moved from the upper end of the suction chamber 131 to its lower end. Since the pistons 161 in this case move from their upper to their bottom dead center, while the gas from the channel 180 is sucked into the suction chamber 131.

By a further rotation, the pistons 161 reach the pressure chamber 141. The space formed by the pistons 161 with the valve disk 101 decreases from the (with respect to FIG. 2) lower end of the pressure chamber 141 to the upper end, whereby the gas is further compressed. This is therefore a second compression stage. The gas then passes into the channel 181, the

Pressure chamber 141 connects to the suction chamber 132. By a further rotation of the distributor disc 102, the pistons 162 are now moved from the upper end of the suction chamber 132 to its lower end. In this case, since the pistons 162 move from their upper to their bottom dead center, the gas is sucked out of the channel 181 into the suction chamber 132. By a further rotation, the piston 162 reach the pressure chamber 142. The space formed by the piston 162 with the valve disc 101 thereby decreases from the lower end (with respect to FIG. 2) of the pressure chamber 142 to the upper end, whereby the gas is further compressed , This is therefore a third compression level. The gas is then discharged through the pressure channel 121 and the discharge port 120.

Claims

claims

Axial piston machine (100) for compressing a gas, having a suction opening (110) and a discharge opening (120) for gas,

wherein in a conveying path for the gas between the suction opening (1 10) and the discharge opening (120) at least two suction chambers (130, 131, 32) and to each suction chamber (130, 131, 132) an associated pressure chamber (140, 141, 142 ) are provided

wherein the suction chambers (130, 131, 132) and the pressure chambers (140, 141, 142) are arranged alternately and beginning with a suction chamber (130), which communicates with the suction port (1 10) along the conveying path, and

wherein the last pressure chamber (142) along the conveying path with the

Ejection opening (120) and the other pressure chambers (140, 141) in each case with the subsequent in the conveying path suction chamber (131, 132) are in communication.

Axial piston machine (100) according to claim 1, wherein the axial piston machine (100) has a valve disc (101), which has the suction chambers (130, 131, 132) and the pressure chambers (140, 141, 142).

Axial piston machine (100) according to claim 2, wherein the connection between a pressure chamber and a subsequent suction chamber in each case as a channel (180, 181) in the valve disc (101) is formed.

Axial piston machine (100) according to claim 2 or 3, wherein the suction chambers (130, 131, 32) and the pressure chambers (140, 141, 142) each as an arcuate

Recesses in the valve disc (101) are formed.

Axial piston machine (100) according to claim 4, wherein each suction chamber (130, 131, 132) and the subsequent pressure chamber in the conveying path (140, 141, 142) each with the same radial distance to a rotational axis of the axial piston machine (100) in the valve disc (101). are provided.

6. axial piston machine (100) according to claim 4 or 5, wherein a in the conveying path to another suction chamber subsequent suction chamber radially with respect to a Rotation axis of the axial piston machine (100) within this other

Suction chamber is provided.

7. axial piston machine (100) according to any one of the preceding claims, wherein the axial piston machine (100) has a distributor disc (102) in which a plurality of pistons (160, 161, 162) of the axial piston machine (100) can be guided.

8. axial piston machine (100) according to claim 7, wherein each piston (160, 161, 162) is associated with a suction chamber and a suction chamber in the conveying path subsequent pressure chamber, so that with this piston and a

corresponding piston associated guide channel (160 ', 161', 162 ') in the distributor disc (102) only the associated suction chamber and the associated pressure chamber, a space for gas is formed.

9. Axial piston machine (100) according to claim 8, wherein a number of pistons, which are associated with a suction chamber and a pressure chamber, is the same for two in the conveying path consecutive suction chambers or decreases.

10. Axial piston machine (100) according to claim 8 or 9, wherein guide channels (162 ') of two adjacent pistons (162), which are respectively assigned to the last suction chamber (132) and the last pressure chamber (142) in the conveying path, communicate with each other.