CN214998245U

CN214998245U - High-temperature high-pressure high-speed chemical pump

Info

Publication number: CN214998245U
Application number: CN202121527085.0U
Authority: CN
Inventors: 潘世群; 王立
Original assignee: Changsha Zhonglian Pump Co ltd
Current assignee: Changsha Zhonglian Pump Co ltd
Priority date: 2021-07-06
Filing date: 2021-07-06
Publication date: 2021-12-03
Anticipated expiration: 2031-07-06

Abstract

The utility model discloses a high-temperature high-pressure high-speed chemical pump, which comprises a pump cover, a mechanical seal gland, a mechanical seal, a heat exchanger, a shaft sleeve, a pressure relief bush, a throttling bush, a metal seal ring, a suction cavity, a high-pressure cavity, a low-pressure cavity and a seal cavity; a pressure relief bushing and a throttle bushing are embedded in an inner hole of the pump cover, the shaft sleeve is sleeved on the pump shaft, the right end of the pump cover is connected with the mechanical seal gland, the mechanical seal gland is arranged on the shaft sleeve, and the metal seal ring is arranged in the inner hole of the shaft sleeve; the suction cavity is a cavity part of the pump body inlet and the impeller inlet, the high-pressure cavity is formed by a part which is positioned outside the impeller outlet and in the inner cavity of the pump body, and the sealing cavity is a cavity inside the mechanical sealing cover. The utility model provides a mechanical seal and the static operating problem of sealing under high temperature high pressure operating mode of chemical pump, improved the security and the reliability of chemical pump, practiced thrift the operation maintenance cost simultaneously.

Description

High-temperature high-pressure high-speed chemical pump

Technical Field

The utility model relates to an industrial pump field especially relates to a high-temperature high-pressure high-speed chemical pump.

Background

The chemical pump, especially the petrochemical process pump, is widely applied in the petrochemical industry, the working condition of the petrochemical industry is mostly the situation of high temperature and high pressure, the temperature is up to 200-450 ℃, and the pressure is up to 5.0 MPa. The chemical pump in the prior art is usually applied to common working conditions, the temperature is less than 135 ℃, the pressure is less than 1.6MPa, and for high-temperature and high-pressure working conditions, the chemical pump in the prior art has no function, so that the static sealing problem between the shaft sleeve and the pump shaft under the high-temperature condition can not be solved, and the sealing problem of mechanical sealing under the high-temperature and high-pressure condition can not be solved. For the sealing between the shaft sleeve and the pump shaft under the condition of high temperature, the chemical pump in the prior art usually uses a rubber sealing ring, the highest temperature resistance of the chemical pump is only 135 ℃, and the application requirement can not be met. In order to reduce the temperature of the sealed cavity, the prior art often adopts a cooling cavity added on the pump cover, however, the cooling effect is limited, the temperature of the medium can be reduced by only tens of degrees, and the sealed cavity still faces the test of high temperature; in order to bear the high pressure of the sealing cavity, a plurality of mechanical seals are used, the axial size of the sealing cavity is increased, the reliability of the mechanical seal is reduced, meanwhile, the sealing surface of the mechanical seal is seriously abraded under the action of high temperature, and the service life of the static sealing rubber sealing ring is shortened, so that the sealing failure and the failure are frequent.

Therefore, the chemical pump in the prior art is difficult to adapt to the high-temperature and high-pressure working condition, has the defects of poor sealing effect, high failure rate, frequent shutdown, poor safety and reliability, and increases the maintenance cost.

Disclosure of Invention

In order to solve the problem, the utility model provides a high-temperature high-pressure high-speed chemical pump through using pressure release bush, throttle bush and heat exchanger, adopts measures such as throttle step-down, reposition of redundant personnel heat transfer, makes sealed chamber become low temperature low pressure by high temperature high pressure, has improved mechanical seal's reliability and security, uses metal seal circle simultaneously, has solved the static seal problem under the high temperature high pressure situation between axle sleeve and the pump shaft.

The utility model adopts the technical proposal that:

a high-temperature high-pressure high-speed chemical pump comprises a pump cover, a mechanical seal gland, a mechanical seal, a heat exchanger, a shaft sleeve, a pressure relief bushing, a throttling bushing and a metal sealing ring; a pressure relief bushing and a throttle bushing are sequentially embedded in the inner hole of the pump cover from left to right, the shaft sleeve is sleeved on the pump shaft, the right end of the pump cover is connected with the mechanical seal gland, the mechanical seal gland is arranged on the shaft sleeve, and the metal seal ring is arranged in the inner hole of the shaft sleeve; further comprising: the device comprises a suction cavity, a high-pressure cavity, a low-pressure cavity and a sealing cavity; the suction cavity is a cavity part of the pump body inlet and the impeller inlet; the high-pressure cavity is formed by a part which is positioned outside the impeller outlet and in the inner cavity of the pump body; the low-pressure cavity is arranged between the pressure relief bushing and the throttling bushing and is formed by the pump cover, the shaft sleeve, the pressure relief bushing and the throttling bushing in a surrounding mode; the sealing cavity is a cavity inside the mechanical sealing cover, and the mechanical seal is arranged in the sealing cavity; the mechanical seal gland is provided with a sealing liquid inlet and a sealing liquid outlet; the sealing liquid inlet is positioned at the lower part of the mechanical sealing cover, and the sealing liquid outlet is positioned at the upper part of the mechanical sealing cover; the heat exchanger is provided with a high-temperature inlet, a low-temperature outlet, a cooling liquid inlet and a cooling liquid outlet, the high-temperature inlet and the low-temperature outlet are respectively an inlet and an outlet of a cooled pumping medium, and the cooling liquid inlet and the cooling liquid outlet are respectively an inlet and an outlet of externally connected cooling liquid; the pump body inlet flange is provided with a first pipe joint; the pump cover is provided with a second pipe joint; the second pipe joint is connected with the high-temperature inlet through a third connecting pipe, the low-temperature outlet is connected with the sealing liquid inlet through a first connecting pipe, and the sealing liquid outlet is connected with the first pipe joint through a second connecting pipe; the pressure relief bushing inner hole with be equipped with radial clearance pressure relief clearance between the axle sleeve excircle, throttle bushing inner hole with be equipped with radial clearance throttle clearance between the axle sleeve excircle.

As a further improvement, the utility model also comprises a high-speed coupler and a variable-frequency high-speed motor, the pump shaft is connected with the variable-frequency high-speed motor through the high-speed coupler.

As a further improvement, the pressure relief gap is used for adjusting the high pressure chamber to the pressure of the medium that the low pressure chamber leaked plays the effect of reducing medium pressure.

As a further improvement of the present invention, the throttling gap is used for adjusting the flow of the medium leaked from the low-pressure chamber to the seal chamber, thereby playing a throttling role.

As a further improvement of the present invention, the metal seal ring is used for radial sealing between the shaft sleeve and the pump shaft, the metal seal ring is composed of a hollow metal ring, and inert gas is filled inside, and the metal seal ring is made of an alloy material.

As a further improvement of the utility model, the inner holes of the pressure relief bushing and the throttling bushing are provided with a plurality of annular grooves for increasing the flow resistance; the pressure relief bushing and the throttling bushing are made of materials with a certain hardness difference with the material of the shaft sleeve.

As a further improvement of the utility model, when the temperature of the sealing cavity is higher than 120 ℃, the mechanical seal is a metal bellows type mechanical seal.

Compared with the prior art, the beneficial effects of the utility model are that:

the utility model discloses an use pressure release bush, throttle bush and heat exchanger, adopt measures such as throttle step-down, reposition of redundant personnel heat transfer, make sealed chamber become low temperature low pressure by high temperature high pressure, improved mechanical seal's life-span, use metal seal simultaneously, solved between axle sleeve and the pump shaft static seal problem under the high temperature high pressure situation. The utility model provides the high security and the reliability of chemical pump have practiced thrift the operation maintenance cost simultaneously.

Drawings

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with the description, do not constitute a limitation of the invention, in which:

fig. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a schematic structural view of part i of fig. 1.

In the figure: 1. the pump body, 2, a pump cover, 3, an impeller, 4, a machine seal gland, 5, a shaft sleeve, 6, a mechanical seal, 7, a heat exchanger, 8, a high-speed coupler, 9, a variable-frequency high-speed motor, 10, a first connecting pipe, 11, a second connecting pipe, 12, a pressure relief bushing, 13, a throttling bushing, 14, a metal sealing ring, 15, a pump shaft, 16, a third connecting pipe, 100, a suction cavity, 101, a high-pressure cavity, 102, a first pipe joint, 121, a pressure relief gap, 131, a throttling gap, 200, a low-pressure cavity, 201, a second pipe joint, 400, a sealing cavity, 401, a sealing liquid inlet, 402, a sealing liquid outlet, 701, a high-temperature inlet, 702, a low-temperature outlet, a cooling liquid inlet, 704 and a cooling liquid outlet.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "both ends", "one end", "the other end" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element to which the reference is made must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "disposed," "connected," and the like are to be construed broadly, and for example, "connected" may be a fixed connection, a detachable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

As shown in fig. 1 to fig. 2, the utility model provides a high-temperature high-pressure high-speed chemical pump, including pump cover 2, machine seal gland 4, mechanical seal 6, heat exchanger 7, axle sleeve 5, pressure release bush 12, throttle bush 13 and metal seal 14. The inner hole of the pump cover 2 is sequentially embedded with a pressure relief bush 12 and a throttle bush 13 from left to right, the pump shaft 15 is sleeved with the shaft sleeve 5, the right end of the pump cover 2 is connected with the mechanical seal cover 4, the shaft sleeve 5 is sleeved with the mechanical seal 6, and the inner hole of the shaft sleeve 5 is arranged with the metal seal ring 14. The utility model discloses still include: the suction cavity 100 is a cavity part of an inlet of the pump body 1 and an inlet of the impeller 3, the high pressure cavity 101 is formed by a part which is arranged outside an outlet of the impeller 3 and is positioned in an inner cavity of the pump body 1, the low pressure cavity 200 is arranged between the pressure relief bush 12 and the throttle bush 13 and is formed by a pump cover 2, a shaft sleeve 5, the pressure relief bush 12 and the throttle bush 13 in a surrounding mode, the sealing cavity 400 is a cavity inside the mechanical sealing cover 4, and the mechanical seal 6 is arranged in the sealing cavity 400. The mechanical seal cover 4 is provided with a seal liquid inlet 401 and a seal liquid outlet 402. The sealing liquid inlet 401 is located at the lower part of the mechanical seal cover 4, and the sealing liquid outlet 402 is located at the upper part of the mechanical seal cover 4. The heat exchanger 7 is provided with a high-temperature inlet 701, a low-temperature outlet 702, a cooling liquid inlet 703 and a cooling liquid outlet 704, the high-temperature inlet 701 and the low-temperature outlet 702 are respectively an inlet and an outlet of a cooled pumping medium, and the cooling liquid inlet 703 and the cooling liquid outlet 704 are respectively an inlet and an outlet of an externally connected cooling liquid. The pump body 1 inlet flange is provided with a first pipe interface 102. The pump cover 2 is provided with a second pipe interface 201. The second pipe joint 201 and the high temperature inlet 701 are connected by a third joint pipe 16, the low temperature outlet 702 and the sealing liquid inlet 401 are connected by a first joint pipe 10, and the sealing liquid outlet 402 and the first pipe joint 102 are connected by a second joint pipe 11. A radial gap pressure relief gap 121 is arranged between the inner hole of the pressure relief bush 12 and the outer circle of the shaft sleeve 5, and the pressure relief gap 121 is used for adjusting the pressure of a medium leaked from the high-pressure cavity 101 to the low-pressure cavity 200 and plays a role in reducing the pressure of the medium. A radial gap throttling gap 131 is arranged between the inner hole of the throttling bush 13 and the excircle of the shaft sleeve 5, and the throttling gap 131 is used for adjusting the flow of a medium leaked from the low-pressure cavity 200 to the sealing cavity 400, so that the throttling effect is achieved.

The utility model discloses still include high-speed shaft coupling 8 and frequency conversion high-speed motor 9, pump shaft 15 passes through high-speed shaft coupling 8 with frequency conversion high-speed motor 9 and is connected. In the prior art, speed increasing is realized through a speed increasing gear, the speed increasing gear is complex in structure and high in cost, main parts are a low-speed gear and a high-speed gear, the precision requirement is high, particularly the high-speed gear is easy to damage, the failure rate is high, and the maintenance cost is also high. The utility model discloses a high rotational speed of high-speed chemical pump is realized through the frequency conversion acceleration rate, is improved the frequency of power by the converter to improve the rotational speed of motor, this kind of acceleration rate mode is simple reliable, and efficiency is higher, therefore the cost is lower. The use of high-speed shaft coupling 8 has then guaranteed the utility model discloses a transmission precision and reliability.

The metal sealing ring 14 is used for radial sealing between the shaft sleeve 5 and the pump shaft 15, and the metal sealing ring 14 is composed of a hollow metal ring, is filled with inert gas and is made of alloy materials. Due to the all-metal structure, the metal sealing ring 14 can resist high temperature and high pressure, can resist the temperature of 450 ℃ and has the pressure of 5.0 MPa. The metal seal ring 14 is filled with gas to have good compensation and thus better sealing performance. The static seal between the pump body 1 and the pump cover 2 and the static seal between the pump cover 2 and the mechanical seal gland 4 can adopt metal wound gaskets and can completely bear high temperature and high pressure.

The inner holes of the pressure relief bush 12 and the throttling bush 13 are provided with a plurality of annular grooves for increasing the flow resistance. The material of the pressure relief bush 12 and the throttle bush 13 has a certain hardness difference from the material of the sleeve 5.

When the temperature of the sealing cavity 400 is higher than 120 ℃, the mechanical seal 6 is a metal bellows type mechanical seal; when the temperature of the capsule 400 is below 120 c, a conventional mechanical seal may be used.

According to the working principle of the present embodiment, as shown in fig. 1, the high-temperature medium flows in from the inlet of the chemical pump, i.e., enters the suction chamber 100, and is sucked in through the inlet of the impeller 3. Under the action of high-speed centrifugal force of the impeller 3, a medium is pressurized and then enters the high-pressure cavity 101, the pressure of the medium in the high-pressure cavity 101 is generally 4.0-5.0 MPa, and the temperature is generally 300-450 ℃. Then, most of the medium in the high-pressure cavity 101 flows out of an outlet of the chemical pump and enters a process pipeline system; a small part of medium flows centripetally from a gap between the back of the impeller 3 and the front of the pump cover 2, and then flows into the low-pressure cavity 200 through a pressure relief gap 121 between the pressure relief bushing 12 and the shaft sleeve 5, when the medium flows through the pressure relief gap 121, the pressure of the medium is reduced from high pressure to low pressure, the pressure of the low-pressure cavity 200 is generally 1.0-1.6 MPa, and the temperature is still 300-450 ℃. Next, most of the medium in the low-pressure chamber 200 flows out from the second pipe joint 201, passes through the third connecting pipe 16, flows into the heat exchanger 7 from the high-temperature inlet 701 of the heat exchanger 7, the high-temperature medium is changed into a low-temperature medium with a temperature lower than 120 ℃ after being cooled by the cooling liquid in the heat exchanger 7, and finally the low-temperature medium flows out from the low-temperature outlet 702 of the heat exchanger 7, and enters the sealed chamber 400 from the sealing liquid inlet 401 through the first connecting pipe 10; a small amount of medium in the low-pressure chamber 200 directly flows into the seal chamber 400 through the throttling gap 131, and the flow rate of the medium is small and negligible due to the good throttling effect of the throttling gap 131. Due to the pressure reduction effect of the pipeline of the heat exchanger 7 and the throttling clearance 131, the pressure in the sealing cavity 400 is further reduced, and the pressure is lower than 1.0 MPa. The low-temperature and low-pressure medium flowing into the seal cavity 400 has the function of sealing liquid and plays a role in cooling, flushing and lubricating the mechanical seal 6. After absorbing the friction heat of the end face of the mechanical seal 6, the temperature of the medium slightly rises, and then the medium flows out from the sealing liquid outlet 402, passes through the second adapter 11, and finally flows back to the suction cavity 100 of the chemical pump inlet from the first pipe connector 102, and a cycle is completed.

Because the temperature of the medium in the sealing cavity 400 is lower than 120 ℃, the pressure is lower than 1.0MPa, and the mechanical seal belongs to a low-temperature and low-pressure environment, the reliability and the safety of the mechanical seal 6 are improved, and the service life of a chemical pump is prolonged.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.

Claims

1. A high-temperature high-pressure high-speed chemical pump is characterized in that: the mechanical seal device comprises a pump cover, a mechanical seal gland, a mechanical seal, a heat exchanger, a shaft sleeve, a pressure relief bushing, a throttling bushing and a metal sealing ring; a pressure relief bushing and a throttle bushing are sequentially embedded in the inner hole of the pump cover from left to right, the shaft sleeve is sleeved on the pump shaft, the right end of the pump cover is connected with the mechanical seal gland, the mechanical seal gland is arranged on the shaft sleeve, and the metal seal ring is arranged in the inner hole of the shaft sleeve;

further comprising: the device comprises a suction cavity, a high-pressure cavity, a low-pressure cavity and a sealing cavity; the suction cavity is a cavity part of the pump body inlet and the impeller inlet; the high-pressure cavity is formed by a part which is positioned outside the impeller outlet and in the inner cavity of the pump body; the low-pressure cavity is arranged between the pressure relief bushing and the throttling bushing and is formed by the pump cover, the shaft sleeve, the pressure relief bushing and the throttling bushing in a surrounding mode; the sealing cavity is a cavity inside the mechanical sealing cover, and the mechanical seal is arranged in the sealing cavity;

the mechanical seal gland is provided with a sealing liquid inlet and a sealing liquid outlet; the sealing liquid inlet is positioned at the lower part of the mechanical sealing cover, and the sealing liquid outlet is positioned at the upper part of the mechanical sealing cover; the heat exchanger is provided with a high-temperature inlet, a low-temperature outlet, a cooling liquid inlet and a cooling liquid outlet, the high-temperature inlet and the low-temperature outlet are respectively an inlet and an outlet of a cooled pumping medium, and the cooling liquid inlet and the cooling liquid outlet are respectively an inlet and an outlet of externally connected cooling liquid; the pump body inlet flange is provided with a first pipe joint; the pump cover is provided with a second pipe joint; the second pipe joint is connected with the high-temperature inlet through a third connecting pipe, the low-temperature outlet is connected with the sealing liquid inlet through a first connecting pipe, and the sealing liquid outlet is connected with the first pipe joint through a second connecting pipe;

the pressure relief bushing inner hole with be equipped with radial clearance pressure relief clearance between the axle sleeve excircle, throttle bushing inner hole with be equipped with radial clearance throttle clearance between the axle sleeve excircle.

2. The high-temperature high-pressure high-speed chemical pump according to claim 1, characterized in that: the pump shaft is connected with the variable-frequency high-speed motor through the high-speed coupler.

3. The high-temperature high-pressure high-speed chemical pump according to claim 1, characterized in that: the pressure relief gap is used for adjusting the pressure of the medium leaked from the high-pressure cavity to the low-pressure cavity, and the function of reducing the pressure of the medium is achieved.

4. The high-temperature high-pressure high-speed chemical pump according to claim 1, characterized in that: the throttling gap is used for adjusting the flow of a medium leaked from the low-pressure cavity to the sealing cavity, and the throttling function is achieved.

5. The high-temperature high-pressure high-speed chemical pump according to claim 1, characterized in that: the metal sealing ring is used for radially sealing between the shaft sleeve and the pump shaft, consists of a hollow metal ring, is filled with inert gas and is made of alloy materials.

6. The high-temperature high-pressure high-speed chemical pump according to claim 1, characterized in that: the inner holes of the pressure relief bushing and the throttling bushing are provided with a plurality of annular grooves for increasing the flow resistance; the pressure relief bushing and the throttling bushing are made of materials with a certain hardness difference with the material of the shaft sleeve.

7. The high-temperature high-pressure high-speed chemical pump according to claim 1, characterized in that: when the temperature of the sealing cavity is higher than 120 ℃, the mechanical seal is a metal bellows type mechanical seal.