Internal gear pump

Abstract

Provided is an internal gear pump, which includes a bracket (1), a pump housing (7) connected to the bracket, and a seal (2) meeting the API682 standard. The bracket is used to support the drive shaft (3) of the internal gear pump, one end of the drive shaft is connected to a driving gear (4), and the pump housing is used to accommodate the driving gear and a driven gear meshing with the driving gear; a cavity (5) is formed in the bracket, and the size of the cavity is configured to be able to accommodate the seal meeting the API682 standard. The seal is located in the cavity, sleeved on the drive shaft, and sealingly abuts against the bracket on the side close to the pump housing. By applying the seal meeting the API682 standard to the internal gear pump, the sealing performance of the pump is improved, and the selection range of seals for the internal gear pump is expanded. The internal gear pump according to the present invention facilitates the flushing, disassembly and assembly of the seal, and is convenient for adjusting the gear end face clearance of the pump to meet the requirements of various working conditions.

Description

Technical Field

[0001] The invention relates to the technical field of industrial pumps, and in particular to an internal gear pump. Background Art

[0002] In the field of industrial pumps, especially in the transportation of petrochemical fluids, internal gear pumps are widely used because they can transport media with a wide range of viscosities and thus adapt to a wider range of working conditions. The types of media they transport can range from light, volatile liquids to heavy, viscous liquids, and even semi-solid liquids.

[0003] For any pump, the leakage of its mechanical seal is an important criterion for measuring the quality and service life of the pump. API682 "Pump Shaft Seal Systems for Centrifugal and Rotor Pumps" is a standard for mechanical seals for petroleum and chemical pumps compiled by the American Petroleum Institute. The cartridge mechanical seal that meets this standard is an internationally universal seal, and is widely used in the petroleum and chemical industries due to its low leakage and long seal life.

[0004] However, most of the existing pumps that can be installed with API682 mechanical seals are centrifugal pumps. As for the existing gear pumps, the space for installing seals is too small to install API682 standard mechanical seals, so the gear pumps cannot use API682 standard mechanical seals and do not meet the requirements of API682 standard. In addition, in the case of high viscosity, the space for accommodating seals is too small to cause poor seal lubrication and slow heat dissipation, leading to premature seal failure.

[0005] Meanwhile, in an internal gear pump, a driving wheel and a driven wheel meshing therewith and a crescent plate are arranged in a pump housing for pumping materials. The clearance between the teeth of the driving wheel and the driven wheel and the clearance between the two wheels and the pump housing are related to the viscosity of the material to be transported and affect the pumping efficiency. The viscosity of the material to be pumped will also change due to changes in temperature, for example. In order to enable the pump to be used for the transportation of materials with different viscosities, there is a need to adjust the above clearance to ensure higher pumping efficiency and expand the application range of the pump.

[0006] Moreover, for existing internal gear pumps, it is often inconvenient to replace the seals, for example, the pump housing and pump bracket need to be disassembled, and sometimes even the entire pump needs to be replaced, resulting in long site downtime and large cost losses. In addition, after a pump is assembled, the seal type is difficult to change, making it difficult to meet the seal requirements of different sites.

[0007] In addition, the existing internal gear pumps are not flexible enough in terms of applicability and cannot adapt to different insulation requirements or on-site inlet and outlet pipe directions.

[0008] The purpose of the present invention is to solve at least one aspect of the above-mentioned problems and defects in the prior art as well as other technical problems. Summary of the invention

[0009] The present invention provides an internal gear pump, which includes a bracket, a pump casing connected to the bracket, and a seal that meets the API682 standard, wherein the bracket is used to support the drive shaft of the internal gear pump, one end of the drive shaft is connected to a driving wheel, and the pump casing is used to accommodate the driving wheel and a driven wheel meshed with the driving wheel, wherein a cavity is formed in the bracket, the size of the cavity is configured to accommodate the seal that meets the API682 standard, the seal is located in the cavity, is sleeved on the drive shaft, and sealingly abuts the bracket on a side close to the pump casing.

[0010] According to an example of the present invention, the bracket includes an upper bracket portion, and an opening is formed on the upper bracket portion to facilitate flushing of the seal from the top of the internal gear pump.

[0011] According to an example of the present invention, the internal gear pump also includes a bearing box, the bearing box includes a bearing box shell and a bearing, the bearing box shell is configured to accommodate a bearing therein to support the drive shaft; and the bracket is formed with a mounting portion for mounting the bearing box at one end thereof away from the pump housing; wherein the bearing box shell is detachably mounted in the inner hole of the mounting portion.

[0012] According to an example of the present invention, a size of the inner hole of the mounting portion is set so that the sealing member can be installed into the bracket or removed from the bracket through the inner hole.

[0013] According to an example of the present invention, the bearing box housing is formed with threads on its outer circumferential surface, and corresponding matching threads are formed in the inner hole of the mounting portion, so that the position of the bearing box and the drive shaft relative to the bracket can be adjusted by screwing the bearing box housing relative to the bracket.

[0014] According to an example of the present invention, the bearings are pairs of tapered roller bearings.

[0015] According to an example of the present invention, the bracket includes a connecting portion for connecting to the pump housing; wherein a heat preservation cavity is formed in the connecting portion.

[0016] According to an example of the present invention, the insulation cavity is formed as an annular cavity, and the connecting portion is formed with a plurality of openings leading to the insulation cavity that are evenly distributed around its periphery, so as to introduce insulation medium into the insulation cavity or remove insulation medium from the insulation cavity.

[0017] According to an example of the present invention, a flushing port leading to the inside of the connecting portion is formed at a position on the connecting portion close to the seal to flush the seal.

[0018] According to an example of the present invention, the bracket includes a lower bracket portion, and a liquid receiving groove located below the seal is formed in the lower bracket portion.

[0019] According to an example of the present invention, the connecting portion includes a connecting flange, and the connecting flange is configured to be connectable to different types of pump casings.

[0020] According to an example of the present invention, the types of the pump casing include: the angle between the inlet and the outlet of the pump casing is 90 degrees, and the angle between the inlet and the outlet is 180 degrees.

[0021] According to an example of the present invention, connection holes evenly distributed in the circumferential direction are provided on the connecting flange, so that the direction of the same pump casing can be adjusted.

[0022] According to an example of the present invention, the internal gear pump further includes a pump head connected to the pump casing, and the connection structure between the pump casing and the pump head is configured to be connectable to different types of pump heads.

[0023] In the above exemplary technical solutions, by configuring the bracket of the internal gear pump to be able to accommodate a seal meeting the API682 standard, the internal gear pump meets the API682 seal standard, improves the sealing performance of the internal gear pump, and expands the selection range of seals for the internal gear pump. By forming an opening in the upper bracket portion of the bracket, it is more convenient to flush the seal. Through the detachable arrangement of the bearing housing and the size setting of the inner hole of the mounting portion on the bracket, the disassembly and assembly of the seal and the bearing housing can be realized without disassembling the bracket of the pump, and the disassembly and installation of the seal are more convenient and fast. The bearing housing can axially adjust the clearance so that the clearance between the gear and the pump casing can be adjusted accordingly according to the change of the viscosity or temperature of the pumped material to ensure the highest pumping efficiency. In addition, the pair of tapered roller bearings resist impact force to ensure the stable operation of the pump. The setting of the heat preservation cavity on the bracket meets different heat preservation requirements and can be flexibly applied to various on-site working conditions. The internal gear pump can also flexibly select various pump casing types, pump casing directions, and pump head types, and is more flexibly applicable to various working conditions. Description of the Drawings

[0024] With reference to the following detailed description and drawings, the features and advantages of the embodiments of the present invention will become apparent, wherein:

[0025] Figure 1 A perspective schematic diagram of an internal gear pump showing an exemplary embodiment according to the present invention;

[0026] Figure 2 shows Figure 1 A partially cut-away perspective view of the internal gear pump shown;

[0027] Figure 3 shows Figure 1 An exploded perspective view of the internal gear pump shown; and

[0028] Figure 4 shows Figure 1 A plan sectional view of the internal gear pump shown. Detailed implementation manners

[0029] The technical solution of the present invention will be further specifically described below through embodiments in conjunction with the accompanying drawings. The description of the embodiments of the present invention with reference to the accompanying drawings is intended to explain the general concept of the present invention and should not be construed as a limitation to the present invention.

[0030] In addition, in the following detailed description, for the sake of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments. However, it is obvious that one or more embodiments can be implemented without these specific details. In addition, for the purpose of simplifying the drawings, well-known structures and devices are not shown in a diagrammatic manner.

[0031] As Figure 1 、 2 shown, the internal gear pump includes a bracket 1, a pump housing 7 connected to the bracket, and a seal 2 meeting the API682 standard; wherein the bracket 1 is used to support the drive shaft 3 of the internal gear pump, and one end of the drive shaft 3 is connected to the driving wheel 4; the pump housing 7 is connected to the bracket 1 and is used to accommodate the driving wheel 4 and the driven wheel 8 meshing with the driving wheel 4; as Figure 2 、 3 shown, a cavity 5 is formed in the bracket 1, and the size of the cavity 5 is configured to be able to accommodate the seal 2 meeting the API682 standard. The seal 2 is located in the cavity 5, sleeved on the drive shaft 3, and sealingly abuts against the bracket 1 on the side close to the pump housing 7.

[0032] In this example, the bracket of the internal gear pump is improved so that its cavity 5 can accommodate a seal meeting the API682 standard. Therefore, the internal gear pump meets the sealing requirements of the API682 standard, improves the sealing performance of the internal gear pump, and expands the selection range of the seals of the internal gear pump.

[0033] In the above example, as Figure 2 、 4As shown, the seal 2 meeting the API682 standard is sealingly joined at the bracket 1 of the pump within the cavity 5, thereby forming a good seal for the drive shaft 3 and the spaces within the bracket 1 and the pump housing 7 on the right side of the seal. The seal 2 meeting the API682 standard can be a seal meeting the standards of various versions of API682, or can be seals of various types and forms meeting the API682 standard. Only by way of example, a structure with mating sub-ports (not shown in the figure) can be provided between the seal 2 and the inner wall of the bracket 1 forming the cavity 5, so as to form a better seal therebetween. Exemplarily, the seal between the seal 2 and the inner wall of the bracket 1 forming the cavity 5 is sealed by an O-ring (not shown in the figure), and can withstand higher pressures.

[0034] Those skilled in the art can understand that one of the improvements in the above example is to configure the cavity of the bracket of the internal gear meshing pump to be able to accommodate the seal meeting the API682 standard, breaking the technical prejudice in the prior art that the internal meshing gear pump cannot install the seal meeting the API682 standard, and overcoming the problem in the prior art that the seal meeting the API682 standard can only be applied to centrifugal pumps and cannot be applied to internal meshing gear pumps.

[0035] In order to conveniently flush the seal meeting the API682 standard, the bracket of the internal meshing gear pump according to the present invention has also been correspondingly adjusted, such as Figures 1-3 As shown, the bracket 1 includes an upper bracket portion 11, and an opening 111 is formed on the upper bracket portion 11 to facilitate flushing the seal 2 from the top of the internal meshing gear pump.

[0036] In this example, the opening 111 facilitates the installation of the seal flushing device, so as to facilitate reaching the seal 2 from the top to flush the flushing port 21 of the seal at the 12 o'clock position from the top.

[0037] Preferably, as Figures 1-3 shown, the cavity 5 of the bracket 1 is arranged to be at least partially open laterally. In other words, the seal 2 located within the cavity 5 can be visible and accessible laterally. The open structure of this bracket 1 enables better heat dissipation performance of the seal and facilitates flushing of the seal.

[0038] As Figure 2 、 4 shown, by way of example, the internal meshing gear pump further includes a bearing housing 6, the bearing housing 6 includes a bearing housing shell 61 and a bearing 62, the bearing housing shell 61 is configured to accommodate the bearing 62 therein to support the drive shaft 3; the bracket 1 forms an installation portion 13 for installing the bearing housing 6 at one end thereof away from the pump housing 7; wherein the bearing housing shell 61 is detachably installed in the inner hole 131 of the installation portion 13.

[0039] In the above example, by detachably mounting the bearing housing 61 in the mounting portion 13, the bearing housing can be freely disassembled and replaced.

[0040] Furthermore, the size of the inner hole 131 of the mounting portion 13 is set such that the seal 2 can be installed into the bracket 1 or removed from the bracket 1 through the inner hole 131.

[0041] In this example, since the seal 2 can be installed into the bracket 1 or removed from the bracket 1 through the inner hole 131, for example, when the seal needs to be disassembled, the entire bearing housing can be directly disassembled, and then the seal can be taken out from the inner hole 131. That is to say, when disassembling and assembling the seal, it is not necessary to disassemble the entire pump, nor to disassemble the pump casing 7 and the bracket 1. Therefore, the loss caused by the on-site parking time can be greatly reduced, and at the same time, it is convenient for workers to disassemble, install, and replace the seal more conveniently and quickly and efficiently.

[0042] As an example, in Figure 3 a bearing housing 6 is shown, and the bearing housing is configured as an integral structure. The bearing housing 61 houses: a bearing 62, a bearing gland 63, a rotary shaft seal 64, a front bearing retaining ring 65, a rear bearing retaining ring 67, and a semi-circular shaft ring 68. The above components are sleeved on the drive shaft 3, and the bearing is prevented from loosening by tightening the anti-loosening set screw 611 of the bearing gland. The bearing housing 6 further includes a lock nut and a corresponding lock washer 69 for axially fixing the drive shaft 3 to the bearing housing. The bearing housing is disassembled and assembled as a whole.

[0043] In an internal gear meshing pump, as Figures 2-4 shown, the pump casing 7 is provided with an inlet and an outlet. The driving wheel 4 is connected to the drive shaft 3, and the driven wheel 8 meshes with the driving wheel 4 on the inner side and is eccentrically arranged. The pump head 9 is installed at one end of the pump casing 7 (shown as the right end in Figure 4 ), the driven shaft is fixed to the pump head, the driven wheel 8 is sleeved on the driven shaft, and a crescent plate is also arranged between the driving wheel 4 and the driven wheel 8. During the operation of the internal gear meshing pump, the material enters the pump casing 7 from the inlet, the drive shaft 3 rotates to drive the driving wheel 4 to rotate, and since the driving wheel 4 and the driven wheel 8 are internally meshed, the rotation of the driving wheel 4 drives the driven wheel 8 to rotate. The material is brought from the inlet between the driving wheel 4 and the driven wheel 8, continues to move through the gap between the driving wheel 4 and the driven wheel 8, passes through the crescent plate, and is extruded at the outlet. The tooth clearance between the driving wheel 4 and the driven wheel 8 and the axial clearance between the gear end faces of the two wheels and the pump casing play a crucial role in the pumping efficiency of the material. To ensure the pumping efficiency, it is necessary to adjust the clearance accordingly with the change of the viscosity of the pumped material.

[0044] Therefore, exemplarily, as Figure 2 、 4As shown, in the present invention, a thread 618 is formed on the outer peripheral surface of the bearing housing 61, and a corresponding mating thread is formed in the inner hole 131 of the mounting portion 13, so that the position of the bearing housing 6 and the drive shaft 3 relative to the bracket 1 can be adjusted by screwing the bearing housing 61 relative to the bracket 1.

[0045] In this example, since the drive shaft 3 is supported by bearings in the bearing housing 61, when the bearing housing 6 is moved by screwing the bearing housing 61, the drive shaft 3 is simultaneously moved, driving the driving wheel 4 at one end thereof to axially move, thereby adjusting the clearance between the gear end face of the driving wheel 4 and the pump housing. Through the above structure, the appropriate axial clearance can be adjusted at any time, so that the pump can be applied to the transportation of materials with different viscosities to ensure the highest transportation efficiency.

[0046] As an example, when installing and adjusting the bearing housing 6, the bearing housing 6 can be rotated clockwise to the non-screw-in position. At this time, the axial clearance between the driving wheel 4 and the pump housing (i.e., the pump head 9) is zero. Rotating the bearing housing 6 counterclockwise can adjust this axial clearance. After adjusting the clearance to the required value, tighten the anti-loosening set screw 610 of the bearing housing to prevent the bearing housing from loosening.

[0047] Preferably, the bearing 62 is a pair of tapered roller bearings. Since the gear is subjected to pressure impacts from the pumped material fluid during the pumping process, such as the impact of pressure pulses, the drive shaft is prone to axial movement. By providing tapered roller bearings, the axial and radial combined loads experienced by the drive shaft can be borne simultaneously, ensuring the smooth operation of the pump and increasing the service life of the pump.

[0048] An insulation cavity (or insulation jacket) is often provided in the pump housing 7 or the pump head 9 to realize the insulation of the material by introducing different insulation media according to the insulation requirements of the material. Further, in the present invention, as Figures 1-3 shown, an insulation cavity is provided in the bracket 1. Specifically, the bracket 1 includes a connecting portion 14 for connecting the pump housing 7 (shown as the right part of the bracket in Figures 1-3 ) ; wherein, an insulation cavity 141 is formed in the connecting portion 14. With this structure, different insulation combinations can be selected according to the insulation requirements of the material. For example, when the insulation requirement for the material is not very high, the pump housing or pump head with an insulation cavity can no longer be selected, and the insulation requirement can be met only through the insulation cavity of the bracket. Or when the insulation requirement for the material is high, the insulation cavity in the connecting portion 14 of the bracket can be used together with the insulation cavity of the pump housing or pump head to insulate the material and enhance the insulation performance.

[0049] As an example, the heat preservation cavity 141 is formed as an annular cavity, and a plurality of openings 142 leading to the heat preservation cavity 141 and evenly distributed around its outer periphery are formed on the connecting portion 14 to introduce the heat preservation medium into the heat preservation cavity 141 or export the heat preservation medium from the heat preservation cavity 141. By providing a plurality of (for example, three) evenly distributed openings 142, any two openings can be selected to connect the supply device of the heat preservation medium according to the position conditions of the on-site layout, and the remaining openings can be blocked. Therefore, it can be flexibly applied to various on-site working conditions.

[0050] Those skilled in the art can understand that since the cavity 5 of the bracket 1 is large enough, in addition to the seals meeting the API682 standard, other types of seals can also be accommodated in this cavity. Therefore, when the on-site process is relatively harsh and there are fewer available seal types to choose from, it is also possible to consider replacing with a more suitable seal type. In addition to being able to install the assembled mechanical seal meeting the API682 standard, the cavity of the bracket 1 is also suitable for the installation of various forms of seals, such as: single-end face seal, double-end face seal, series mechanical seal, ordinary assembled mechanical seal; bulk mechanical seal; packing seal; triple-lip seal and other various forms of seals. In order to adapt to the flushing of various seals, preferably, as Figure 1 shown, a flushing port 143 leading to the inside of the connecting portion 14 is also formed at a position on the connecting portion 14 close to the seal 2 to flush the seal 2. Therefore, the internal gear pump of the present invention can select a wider range of types of seals and be applicable to more working conditions.

[0051] Preferably, as Figure 1 、 2 shown, the bracket 1 includes a lower bracket portion 12, and a liquid receiving groove located below the seal 2 is formed inside the lower bracket portion 12. The liquid receiving groove is used to prevent the leakage of the seal from polluting the environment.

[0052] As Figures 1-3 shown, the connecting portion 14 of the bracket includes a connecting flange 144, and the connecting flange 144 is configured to be able to connect to different types of pump casings 7. The types of the pump casing 7 may include: the angle between the inlet and the outlet of the pump casing 7 is 90 degrees, or the angle between the inlet and the outlet is 180 degrees. Further, connecting holes evenly distributed in the circumferential direction are provided on the connecting flange 144, so that the direction of the same pump casing 7 can also be adjusted at any time. Through the structure of the connecting flange 144, for example, the connecting flange 144 of the bracket 1 and the pump casing 7 can be connected by fasteners such as bolts, and the inlet and outlet directions of the pump casing 7 can be adjusted at any time according to the needs of the process, so that the form of the pump and the connection direction of the inlet and outlet can be changed at any time, and it can be more flexibly applicable to various working conditions.

[0053] In addition, the interface for pipe connection on the pump housing 7 can be a flange interface (such as ASME standard, DIN standard, etc.), or a threaded interface (NPT, BSP and other standards). Those skilled in the art can make a choice according to the working conditions.

[0054] Preferably, the pump head 9 can be selected from the following types: a pump head with a safety valve 10, a pump head without a safety valve, a pump head with a heat-insulating cavity, or a pump head without a heat-insulating cavity. Those skilled in the art can make a choice according to the needs. Therefore, the internal gear pump of the present invention can be more flexibly applied to various occasions.

[0055] Although some embodiments of the general concept of the present invention have been shown and described, those of ordinary skill in the art will understand that changes can be made to these embodiments without departing from the principles and spirit of the general concept of the present invention. The scope of the present invention is defined by the claims and their equivalents.

Claims

1. An internal gear pump, characterized in that, Comprising: A bracket (1) for supporting the drive shaft (3) of the internal gear pump, with one end of the drive shaft (3) connected to a driving wheel (4). A pump housing (7) connected to the bracket (1) and for accommodating the driving wheel (4) and a driven wheel meshing with the driving wheel (4); and A seal (2) meeting the API682 standard; Wherein a cavity (5) is formed in the bracket (1), and the size of the cavity (5) is configured to be able to accommodate the seal (2) meeting the API682 standard. The seal (2) is located within the cavity (5), sleeved on the drive shaft (3), and sealingly abuts against the bracket (1) on the side close to the pump housing (7), achieving the sealing of the space within the pump housing (7). The bracket (1) includes an upper bracket portion (11) on which an opening (111) is formed to facilitate flushing the seal (2) from the top of the internal gear pump. And the bracket (1) includes a connecting portion (14) for connecting the pump housing (7); wherein, a heat preservation cavity (141) is formed in the connecting portion (14), the heat preservation cavity (141) is formed as an annular cavity, and a plurality of openings (142) uniformly distributed around its outer periphery are formed on the connecting portion (14) to introduce or export a heat preservation medium to or from the heat preservation cavity (141). And a flushing port (143) leading to the inside of the connecting portion (14) is formed at a position on the connecting portion (14) close to the seal (2) to flush the seal (2).

2. The internal gear pump according to claim 1, characterized in that The internal gear pump further includes a bearing housing (6), the bearing housing (6) includes a bearing housing body (61) and bearings (62), and the bearing housing body (61) is configured to accommodate the bearings (62) therein to support the drive shaft (3); and The bracket (1) forms a mounting portion (13) for mounting the bearing housing (6) at one end away from the pump housing (7); Wherein the bearing housing body (61) is detachably mounted in the inner hole (131) of the mounting portion (13).

3. The internal gear pump according to claim 2, characterized in that The size of the inner hole (131) of the mounting portion (13) is set such that the seal (2) can be installed into or removed from the bracket (1) through the inner hole (131).

4. The internal gear pump according to claim 2 or 3, characterized in that The bearing housing body (61) forms a thread on its outer peripheral surface, and a corresponding mating thread is formed in the inner hole (131) of the mounting portion (13), so that the position of the bearing housing (6) and the drive shaft (3) relative to the bracket (1) can be adjusted by screwing the bearing housing body (61) relative to the bracket (1).

5. The internal gear pump according to claim 2 or 3, characterized in that the bearing (62) is a pair of tapered roller bearings.

6. The internal gear pump according to any one of claims 1-3, characterized in that the bracket (1) includes a lower bracket portion (12), and a liquid receiving groove located below the seal (2) is formed in the lower bracket portion (12).

7. The internal gear pump according to claim 1, characterized in that the connecting portion (14) includes a connecting flange (144), and the connecting flange (144) is configured to be connectable to different types of pump casings (7).

8. The internal gear pump according to claim 7, characterized in that the types of the pump casing (7) include: the angle between the inlet and the outlet of the pump casing (7) is 90 degrees, or the angle between the inlet and the outlet is 180 degrees.

9. The internal gear pump according to claim 7, characterized in that the connecting flange (144) is provided with connecting holes evenly distributed in the circumferential direction, so that the direction of the same pump casing (7) can be adjusted.

10. The internal gear pump according to any one of claims 1-3 and 7-9, characterized in that the internal gear pump further includes a pump head (9) connected to the pump casing (7), and the connection structure between the pump casing (7) and the pump head (9) is configured to be connectable to different types of pump heads (9).

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