CN219672711U

CN219672711U - Urea conveying device and engineering machinery

Info

Publication number: CN219672711U
Application number: CN202320342552.5U
Authority: CN
Inventors: 张鑫; 袁卓敏; 沈小健; 余炯
Original assignee: Zoomlion Earth Moving Machinery Co Ltd; Shaanxi Zoomlion West Earthmoving Machinery Co Ltd
Current assignee: Zoomlion Earth Moving Machinery Co Ltd; Shaanxi Zoomlion West Earthmoving Machinery Co Ltd
Priority date: 2023-02-28
Filing date: 2023-02-28
Publication date: 2023-09-12
Anticipated expiration: 2033-02-28

Abstract

The utility model provides a urea conveying device and engineering machinery, wherein the urea conveying device comprises an integrated module, and comprises an integrated shell, a urea pump, a heating pipe and a liquid suction pipe, wherein the urea pump, the heating pipe and the liquid suction pipe are arranged on the integrated shell; the urea tank is provided with a urea cavity and an installation opening communicated with the urea cavity, the integrated shell and the urea tank are detachably connected and used for plugging the installation opening, and the urea cavity is used for containing urea aqueous solution and allowing the heating pipe and the liquid suction pipe to extend in. According to the utility model, the urea pump, the liquid suction pipe and the heating pipe are integrated through the integrated shell, the urea cavity can be plugged, the liquid suction pipe and the heating pipe are accommodated in the urea cavity of the urea tank, and the urea aqueous solution in the urea cavity is sucked and heated through direct contact, so that heat dissipation is avoided, the heating efficiency is improved, and the wire harness cost is reduced.

Description

Urea conveying device and engineering machinery

Technical Field

The utility model belongs to the technical field of engines, and particularly relates to a urea conveying device and engineering machinery.

Background

In an engine aftertreatment system of a construction machine, an aqueous urea solution is required to react with NOx in exhaust gas discharged from an engine in an aftertreatment device to generate harmless gas, and the aqueous urea solution used for the reaction is required to be conveyed to the aftertreatment device by a urea conveying device to react with NOx.

The urea aqueous solution is crystallized in a low temperature environment, so that the urea aqueous solution cannot be used, and therefore, the urea aqueous solution needs to be heated to prevent the urea from crystallizing at a low temperature. The existing urea conveying device is generally connected through an external pipeline by adopting a plurality of split components, a heating resistance wire is arranged on the outer layer of the external pipeline, urea aqueous solution in the external pipeline is heated through the heating resistance wire, and the heating mode is large in heat dissipation and low in heating efficiency, heating power wiring is required to be added, and the wiring harness cost is improved.

Disclosure of Invention

The utility model mainly aims to provide a urea conveying device and engineering machinery, and aims to solve the technical problems of poor heating effect and high wire harness cost of the urea conveying device in the prior art.

In order to achieve the above object, the present utility model provides a urea delivery device for engine exhaust gas treatment of a construction machine, comprising: the integrated module comprises an integrated shell, and a urea pump, a heating pipe and a liquid suction pipe which are arranged on the integrated shell, wherein an antifreezing fluid inlet and an antifreezing fluid outlet which are communicated with the heating pipe are arranged on the integrated shell, the antifreezing fluid inlet is used for allowing antifreezing fluid in the engine to enter the heating pipe, and the antifreezing fluid outlet is used for allowing the antifreezing fluid in the heating pipe to flow back to the engine; the urea tank is provided with a urea cavity and an installation port communicated with the urea cavity, the integrated shell is detachably connected with the urea tank and used for sealing the installation port, and the urea cavity is used for containing urea aqueous solution and is used for the heating pipe to extend into the liquid suction pipe.

In an embodiment of the present utility model, the mounting port is located at an upper end of the urea tank, and the heating pipe extends downward from the upper end of the urea tank to a lower end of the urea tank.

In the embodiment of the utility model, the heating pipe is spirally downwards formed into a spiral cavity, and the liquid suction pipe is arranged in the spiral cavity in a penetrating manner and is attached to the heating pipe.

In the embodiment of the utility model, the urea conveying device further comprises a guide rod and a urea sensor, wherein the guide rod extends downwards from the upper end of the urea tank to the lower end of the urea tank, the urea sensor is arranged at the lower end of the guide rod and is used for detecting the urea content in the urea aqueous solution, and the liquid suction pipe is connected with the guide rod through a binding belt.

In the embodiment of the utility model, the liquid suction pipe extends from the upper end of the urea tank to the lower end of the urea tank, and the lower end of the liquid suction pipe is connected with a urea liquid inlet filter.

In an embodiment of the utility model, the urea delivery device further comprises: the temperature detection piece is arranged on the heating pipe and is used for detecting temperature information of urea aqueous solution; the water-break switch is electrically connected with the temperature detection piece, is installed in the integrated shell and connected to a communicating pipeline between the antifreeze inlet and the heating pipe, and is used for opening or closing the communicating pipeline according to the temperature information.

In the embodiment of the utility model, the urea conveying device further comprises a liquid level detector arranged on the heating pipe, wherein the liquid level detector is used for detecting liquid level information of urea aqueous solution, the water cut-off switch is electrically connected with the liquid level detector, and the water cut-off switch is used for opening or closing the communication pipeline according to the temperature information and the liquid level information.

In the embodiment of the utility model, the integrated shell comprises a main shell with an opening and an upper cover covered at the opening, the main shell is detachably connected with the upper cover, a protection cavity is defined by the upper cover and the main shell, and the urea pump is accommodated in the protection cavity.

In an embodiment of the utility model, the integrated shell is in threaded connection with the urea tank; and/or the urea tank is provided with an air balance valve for balancing the urea cavity and the external air pressure.

The utility model also proposes a construction machine comprising an engine, a post-processor and a urea delivery device as described above.

Through the technical scheme, the urea conveying device provided by the embodiment of the utility model has the following beneficial effects:

the urea pump, the heating pipe and the liquid suction pipe are integrated in the integrated shell, wherein the heating pipe and the liquid suction pipe are positioned at the bottom of the integrated shell, the urea pump and the liquid suction pipe are connected and plugged at the mounting opening through the integrated shell and the urea tank, and the heating pipe and the liquid suction pipe extend into the urea cavity of the urea tank, so that the assembly connection between the urea tank and the integrated module can be completed. When the engine needs to be abandoned, the antifreeze in the engine can enter the heating pipe in the urea cavity through the antifreeze inlet, the urea aqueous solution in the urea cavity is heated through the direct contact of the heating pipe and the urea aqueous solution, the antifreeze in the heating pipe can flow back to the engine through the antifreeze outlet, the urea pump can suck the urea solution in the urea cavity into the post-processor through the liquid suction pipe, and the condition that a pipeline is exposed can be avoided. The integrated module integrates the urea pump, the liquid suction pipe and the heating pipe through the integrated shell, can seal the urea cavity, accommodates the liquid suction pipe and the heating pipe in the urea cavity of the urea tank, sucks and heats urea aqueous solution in the urea cavity through direct contact, can avoid the condition that all parts are connected through exposed pipelines in the prior art, avoids heat dissipation, improves heating efficiency, simultaneously can avoid the condition of adding a heating power supply, and reduces wire harness cost.

Additional features and advantages of the utility model will be set forth in the detailed description which follows.

Drawings

The accompanying drawings are included to provide an understanding of the utility model, and are incorporated in and constitute a part of this specification, illustrate the utility model and together with the description serve to explain, without limitation, the utility model. In the drawings:

FIG. 1 is a schematic view of a urea delivery device according to an embodiment of the present utility model;

FIG. 2 is a schematic cross-sectional view of a urea delivery device according to another embodiment of the utility model;

FIG. 3 is a schematic view showing an exploded structure of a urea delivery device according to an embodiment of the present utility model;

fig. 4 is a schematic diagram illustrating a connection principle of a working machine according to an embodiment of the present utility model.

Description of the reference numerals

Reference number designation number designation

100. Liquid suction pipe of urea conveying device 4

1. Urea tank 5 heating pipe

11. Guide rod of urea cavity 6

12. Filling cover 7 bandage

2. Integrated shell 8 urea feed liquor filter

21. Antifreezing solution inlet 9 temperature detecting piece

22. Antifreezing solution outlet 10 water shutoff switch

23. Main housing 20 level detector

231. Open 200 engineering machinery

232. Engine with sinking groove 210

24. Upper cover 220 post-processor

3. Urea pump

Detailed Description

Specific embodiments of the present utility model will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for purposes of illustration and explanation only and are not intended to limit the present utility model.

The urea delivery device according to the utility model is described below with reference to the accompanying drawings.

As shown in fig. 1 to 3, in an embodiment of the present utility model, a urea delivery device 100 is used for engine 210 exhaust treatment of a construction machine 200, the urea delivery device 100 comprising an integrated module and a urea tank 1; the integrated module comprises an integrated shell 2, a urea pump 3, a heating pipe 5 and a liquid suction pipe 4, wherein the urea pump 3, the heating pipe 5 and the liquid suction pipe 4 are arranged on the integrated shell 2, an antifreezing solution inlet 21 and an antifreezing solution outlet 22 are arranged on the integrated shell 2 and are communicated with the heating pipe 5, the antifreezing solution inlet 21 is used for allowing antifreezing solution in an engine 210 to enter the heating pipe 5, and the antifreezing solution outlet 22 is used for allowing the antifreezing solution in the heating pipe 5 to flow back to the engine 210; the urea tank 1 is provided with a urea cavity 11 and a mounting port communicated with the urea cavity 11, the integrated shell 2 and the urea tank 1 are detachably connected and used for plugging the mounting port, the urea cavity 11 is used for containing urea aqueous solution and allowing the heating pipe 5 and the liquid suction pipe 4 to stretch in, and the urea pump 3 is used for sucking the urea aqueous solution in the urea cavity 11 through the liquid suction pipe 4 and pumping the urea aqueous solution to the post-processor 220 of the engineering machine 200.

It can be understood that the heating pipe 5 and the liquid suction pipe 4 in this embodiment are hollow pipes, the top ends of the liquid suction pipe 4 and the heating pipe 5 are connected with the bottom surface of the integrated shell 2, and the integrated shell 2 is partially extended into the urea cavity 11 under the condition that the integrated shell 2 is connected with the urea tank 1 and the mounting port is plugged. In order to facilitate urea filling, the urea tank 1 is also provided with a filling opening, a filling cover 12 is covered at the filling opening, and the filling opening can be closed or opened through the filling cover 12.

When the urea conveying device 100 in the embodiment is assembled, the urea pump 3, the heating pipe 5 and the liquid suction pipe 4 are integrated in the integrated shell 2, wherein the heating pipe 5 and the liquid suction pipe 4 are positioned at the bottom of the integrated shell 2, the urea conveying device is connected with the urea tank 1 through the integrated shell 2 to be plugged at the mounting opening, and the heating pipe 5 and the liquid suction pipe 4 extend into the urea cavity 11 of the urea tank 1, so that the assembly connection between the urea tank 1 and the integrated module can be completed. When the engine 210 needs to be abandoned, the antifreeze in the engine 210 can enter the heating pipe 5 in the urea cavity 11 through the antifreeze inlet 21, the urea aqueous solution in the urea cavity 11 is heated through the direct contact of the heating pipe 5 and the urea aqueous solution, the antifreeze in the heating pipe 5 can flow back to the engine 210 through the antifreeze outlet 22, the urea pump 3 can suck the urea solution in the urea cavity 11 into the post-processor 220 through the liquid suction pipe 4, the post-processor 220 is enabled to carry out tail gas treatment, and the condition that a pipeline is exposed can be avoided. The integrated module in this embodiment has integrated urea pump 3, pipette 4 and heating pipe 5 through integrated shell 2 to can shutoff urea chamber 11, hold pipette 4 and heating pipe 5 in urea chamber 11 of urea jar 1, absorb and heat urea aqueous solution in urea chamber 11 through direct contact, can avoid among the prior art through the condition of exposing the pipe connection between each part, avoid the heat to scatter and disappear, improved heating efficiency, can also avoid increasing heating power supply's condition simultaneously, reduced the pencil cost.

Specifically, the mounting opening is located at the upper end of the urea tank 1, and the heating pipe 5 extends downward from the upper end of the urea tank 1 to the lower end of the urea tank 1. The urea tank 1 in this embodiment extends along the upper and lower direction, and the extending direction of heating pipe 5 and urea tank 1 is unanimous, and heating pipe 5 can extend to the lower extreme of urea tank 1, has improved the area of contact between urea aqueous solution in heating pipe 5 and the urea chamber 11, can guarantee heating pipe 5 to the heating efficiency of urea aqueous solution. The heating pipe 5 and the pipette 4 may be both provided at the lower end of the integrated housing 2.

As shown in fig. 2 and 3, in the embodiment of the present utility model, the heating tube 5 is spirally downward formed into a spiral cavity, and the pipette 4 is inserted into the spiral cavity and is attached to the heating tube 5. The heating pipe 5 in this embodiment is spiral downwards can further improve the area of contact between heating pipe 5 and the urea aqueous solution, and the pipette 4 stretches into the spiral cavity that heating pipe 5 formed and with heating pipe 5 laminating, realizes the inseparable contact of pipette 4 and heating pipe 5, can guarantee the urea aqueous solution temperature that urea pump 3 passed through the washing liquor pipe suction.

In an embodiment, the urea delivery device 100 further comprises a guiding rod 6 and a urea sensor, the guiding rod 6 extends downwards from the upper end of the urea tank 1 to the lower end of the urea tank 1, the urea sensor is mounted at the lower end of the guiding rod 6 and is used for detecting the urea content in the urea aqueous solution, and the liquid suction pipe 4 is connected with the guiding rod 6 through a binding belt 7.

The guide bar 6 in this embodiment is a hard bar and extends downwards from the lower end of the integrated shell 2 to the lower end of the urea tank 1, and the liquid suction pipe 4 is fixed on the guide bar 6 through the binding belt 7, so that the vertical downward extension direction of the liquid suction pipe 4 is ensured, and a urea sensor is arranged at the lower end of the guide bar 6, and the urea sensor can be connected with a controller of the engineering machine 200, so that the urea content of urea aqueous solution in the urea cavity 11 is monitored through the urea sensor, and the use convenience of the urea conveying device 100 is improved.

The liquid suction pipe 4 extends from the upper end of the urea tank 1 to the lower end of the urea tank 1, and the urea liquid inlet filter 8 is connected to the lower end of the liquid suction pipe 4. The liquid suction pipe 4 in this embodiment extends to the lower extreme of urea jar 1 from the installing port, can make things convenient for urea pump 3 to absorb urea aqueous solution through liquid suction pipe 4 to urea feed liquor filter 8 that liquid suction pipe 4 bottom set up can filter the urea aqueous solution that gets into in the urea pump 3, avoids impurity to get into the condition of urea pump 3 and aftertreatment ware 220, for making things convenient for filter change and maintenance, clearance, offered the filter maintenance mouth on the integrated shell 2, and the lid is equipped with the maintenance lid, when needs change or maintain urea feed liquor filter 8, can open the maintenance lid and take out urea feed liquor filter 8 through the filter maintenance mouth.

As shown in fig. 2 and 3, the urea delivery device 100 further comprises a temperature detecting member 9 and a water cut-off switch 10; the temperature detecting piece 9 is arranged on the heating pipe 5 and is used for detecting temperature information of urea aqueous solution; the water cut-off switch 10 is electrically connected with the temperature detecting member 9, the water cut-off switch 10 is mounted on the integrated housing 2 and connected to the communication pipe between the antifreeze inlet 21 and the heating pipe 5, and the water cut-off switch 10 is used for opening or closing the communication pipe according to temperature information.

In this embodiment, the temperature detecting member 9 may employ a temperature sensor, the water-break switch 10 may employ a water-break electromagnetic valve, the temperature sensor may detect the temperature of the urea aqueous solution in the urea cavity 11 in real time, in an embodiment, when the temperature of the urea aqueous solution reaches a set value, the water-break switch 10 closes the communication pipeline, and when the temperature of the urea aqueous solution is lower than the set value, the water-break switch 10 opens the communication pipeline, so that energy waste caused by overheating of the urea aqueous solution by the heating pipe 5 can be avoided, and the use cost of the urea conveying device 100 is reduced.

Specifically, the urea delivery device 100 further includes a liquid level detector 20 mounted on the heating pipe 5, the liquid level detector 20 is used for detecting liquid level information of urea aqueous solution, the water break switch 10 is electrically connected with the liquid level detector 20, and the water break switch 10 is used for opening or closing a communication pipeline according to the temperature information and the liquid level information. The liquid level detector 20 in this embodiment may adopt a liquid level meter, where the water break switch 10 closes the communication pipeline when the liquid level of the urea aqueous solution drops to a set value, and the water break switch 10 opens the communication pipeline when the liquid level of the urea aqueous solution is higher than the set value, so as to avoid the situation that the urea pump 3 pumps the urea aqueous solution empty. One of the temperature information and the liquid level information reaches the condition of closing the communication line, or both the temperature information and the liquid level information reach the condition of closing the communication line, and the water shutoff switch 10 closes the communication line.

In an embodiment, the temperature detecting member 9 and the liquid level detector 20 may be integrated into a liquid level temperature sensor, and in this embodiment, the urea pump 3, the water-break electromagnetic valve and the liquid level temperature sensor are highly integrated to form a whole, and the urea pump is installed above the urea tank 1, so that an external pipeline between the urea tank 1 and the urea pump 3 and between the water-break electromagnetic valve and the urea tank 1 can be omitted, the pipeline material cost and the installation cost are reduced, the connecting pipeline between the components is reduced, the leakage risk is reduced, and the reliability of the system is improved. In addition, the urea pump 3 and the water-break electromagnetic valve do not need to be independently installed, an additional installation support can be omitted, the additional installation space is not occupied, and the support cost and the installation cost are reduced.

In one embodiment, the integrated housing 2 includes a main housing 23 with an opening 231 and an upper cover 24 covering the opening 231, the main housing 23 and the upper cover 24 are detachably connected, the upper cover 24 and the main housing 23 enclose a protection cavity, and the urea pump 3 is accommodated in the protection cavity. The main housing 23 in this embodiment is provided with a sinking groove 232, the bottom surface of the sinking groove 232 forms a mounting plane, the water break switch 10 is mounted on the mounting plane, and the top surface of the water break switch 10 is flush with the top surface of the main housing 23. The integrated shell 2 in this embodiment is the design of components of a whole that can function independently from top to bottom, can make things convenient for the installation of urea pump 3, heating pipe 5, pipette 4 and water cut-off switch 10, through protection cavity protection urea pump 3, can avoid the condition that urea pump 3 was damaged by other parts, improved urea conveyor 100's stability in use.

As shown in fig. 3, in the embodiment of the utility model, the integrated shell 2 and the urea tank 1 are screwed; the urea tank 1 is provided with an air balance valve for balancing the urea chamber 11 and the outside air pressure. The inner wall of the mounting opening in this embodiment is provided with a screw thread forming screw thread hole, and the lower end of the integrated housing 2 protrudes downward to form a screw thread column, and the heating pipe 5 and the liquid suction pipe 4 are both mounted on the bottom surface of the screw thread column. The air balance valve can balance the urea cavity 11 and the external air pressure, so that the smoothness of the urea pump 3 for absorbing the urea aqueous solution is ensured.

As shown in fig. 4, the present utility model also proposes a construction machine 200, the construction machine 200 comprising an engine 210, a post-processor 220 and the urea delivery device 100 as above, the specific structure of the urea delivery device 100 being referred to the above embodiments. Because the engineering machine 200 adopts all the technical solutions of all the embodiments, at least the technical solutions of the embodiments have all the beneficial effects brought by the technical solutions of the embodiments, and are not described in detail herein.

In the description of the present utility model, it should be understood that the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present utility model, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present utility model, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; may be mechanically connected, may be electrically connected or may be in communication with each other; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present utility model. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

While embodiments of the present utility model have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the utility model, and that variations, modifications, alternatives and variations may be made to the above embodiments by one of ordinary skill in the art within the scope of the utility model.

Claims

1. A urea delivery device for treatment of exhaust gas from an engine (210) of a working machine (200), characterized in that the urea delivery device (100) comprises:

the integrated module comprises an integrated shell (2) and a urea pump (3), a heating pipe (5) and a liquid suction pipe (4) which are arranged on the integrated shell (2), wherein an antifreezing solution inlet (21) and an antifreezing solution outlet (22) which are communicated with the heating pipe (5) are arranged on the integrated shell (2), the antifreezing solution inlet (21) is used for allowing antifreezing solution in an engine (210) to enter the heating pipe (5), and the antifreezing solution outlet (22) is used for allowing the antifreezing solution in the heating pipe (5) to flow back to the engine (210);

the urea tank (1) is provided with a urea cavity (11) and an installation opening communicated with the urea cavity (11), the integrated shell (2) is detachably connected with the urea tank (1) and used for sealing the installation opening, and the urea cavity (11) is used for containing urea aqueous solution and supplying the heating pipe (5) and the liquid suction pipe (4) to stretch in.

2. Urea delivery device according to claim 1, characterized in that the mounting opening is located at the upper end of the urea tank (1), the heating pipe (5) extending downwards from the upper end of the urea tank (1) to the lower end of the urea tank (1).

3. Urea delivery device according to claim 2, characterized in that the heating pipe (5) is spiraled downwards forming a spiral cavity, the pipette (4) being threaded into the spiral cavity and being in abutment with the heating pipe (5).

4. Urea delivery device according to claim 1, characterized in that the urea delivery device (100) further comprises a guiding rod (6) and a urea sensor, the guiding rod (6) extending downwards from the upper end of the urea tank (1) to the lower end of the urea tank (1), the urea sensor being mounted at the lower end of the guiding rod (6) for detecting the urea content in the urea aqueous solution, the pipette (4) being connected to the guiding rod (6) by means of a tie (7).

5. Urea delivery device according to claim 2, characterized in that the pipette (4) extends from the upper end of the urea tank (1) to the lower end of the urea tank (1), the lower end of the pipette (4) being connected with a urea feed filter (8).

6. Urea delivery device according to claim 1, characterized in that the urea delivery device (100) further comprises:

a temperature detection member (9) which is installed on the heating pipe (5) and is used for detecting the temperature information of the urea aqueous solution;

the water-break switch (10) is electrically connected with the temperature detection piece (9), the water-break switch (10) is arranged on the integrated shell (2) and connected to a communicating pipeline between the antifreeze inlet (21) and the heating pipe (5), and the water-break switch (10) is used for opening or closing the communicating pipeline according to the temperature information.

7. Urea delivery device according to claim 6, characterized in that the urea delivery device (100) further comprises a liquid level detector (20) mounted on the heating pipe (5), the liquid level detector (20) being adapted to detect liquid level information of the urea aqueous solution, the water break switch (10) being electrically connected to the liquid level detector (20), the water break switch (10) being adapted to open or close the communication line depending on the temperature information and the liquid level information.

8. Urea delivery device according to any of claims 1-7, characterized in that the integrated housing (2) comprises a main housing (23) with an opening (231) and an upper cover (24) covering the opening (231), the main housing (23) and the upper cover (24) being detachably connected, the upper cover (24) and the main housing (23) enclosing a protection cavity, the urea pump (3) being accommodated in the protection cavity.

9. Urea delivery device according to any of claims 1 to 7, characterized in that the integrated shell (2) and the urea tank (1) are screwed;

and/or the number of the groups of groups,

the urea tank (1) is provided with an air balance valve for balancing the urea cavity (11) and the external air pressure.

10. A working machine, characterized in that the working machine (200) comprises an engine (210), a post-processor (220) and a urea delivery device (100) according to any of claims 1-9.