CN210949156U

CN210949156U - Thrust bearing-free multistage centrifugal pump

Info

Publication number: CN210949156U
Application number: CN201921361790.0U
Authority: CN
Inventors: 李斌; 白书哲
Original assignee: Shenyang Qiyuan Industrial Pump Manufacturing Co ltd
Current assignee: Shenyang Qiyuan Industrial Pump Manufacturing Co ltd
Priority date: 2019-08-21
Filing date: 2019-08-21
Publication date: 2020-07-07
Anticipated expiration: 2029-08-21

Abstract

The utility model provides a thrust bearing free multistage centrifugal pump belongs to multistage centrifugal pump technical field, more specifically says and relates to power of a pump and is less than 1000kW, single casing, horizontal, multistage centrifugal pump. The utility model provides a need not to install footstep bearing, reduce the manufacturing cost of pump and the multistage centrifugal pump of maintenance cost by a wide margin. The utility model discloses a no footstep bearing multistage centrifugal pump, including the pump shaft, the department of spitting out section that lies in the pump on the pump shaft is provided with the balance plate, and the balance plate side is provided with the throttle bush, and the balance plate is outer to be balanced cover, its characterized in that: the balance disc comprises a disc body and a balance shaft sleeve; the disc body is provided with a friction top surface relative to the throttling bush; gaps are arranged between the disc body and the balance sleeve and between the disc body and the throttling bush.

Description

Thrust bearing-free multistage centrifugal pump

Technical Field

The utility model belongs to the technical field of multistage centrifugal pump, more specifically say so and relate to a power of pump is less than 1000kW, single casing, horizontal, multistage centrifugal pump.

Background

Multistage centrifugal pumps are widely used in the industrial field. To achieve high pressure at the outlet of the pump, impellers are typically mounted in series on the pump shaft in stages. During operation of the pump, axial thrust acts on the rotor component, and the axial thrust pulls the rotor component to move axially. Therefore, it is necessary to try to eliminate or balance this axial thrust. The axial thrust of a conventional rotor component is usually borne by a "balance disc a + thrust ball bearing b" combination (see fig. 3, 4). The balance disc a can balance most of the axial thrust, and the residual axial thrust is borne by the thrust ball bearing b. The thrust ball bearing b is arranged in the thrust bearing body d on one side of the pump discharge section.

To prevent media leakage, the shaft end seal typically employs a mechanical seal c, which is disposed between the discharge section and the thrust bearing body d, as shown in fig. 3. The mechanical seal c belongs to a quick-wear part and needs to be periodically disassembled, overhauled and replaced. Before the mechanical seal c is removed, the thrust ball bearing b must be removed. The thrust ball bearing b is of an integral structure and is in transition fit with the bearing sleeve and the pump shaft 1. In order to ensure that the thrust ball bearing b is not damaged during disassembly, the thrust ball bearing b is disassembled by means of a special tool, certain manpower and material resources are wasted, and the overhaul period is prolonged. The thrust ball bearing b must be mounted inside the dedicated thrust bearing body d. The thrust bearing body d, the thrust ball bearing b, and the accessory parts increase the consumption of the lubricating oil, and also increase the manufacturing cost of the pump.

In addition, when the power of the pump is less than 1000kW, most bearings adopt thin oil of an oil slinger for self-lubrication. The oil slinger is directly contacted with the surface of the pump shaft, and the oil slinger is made of pure metal copper or gray cast iron, so that certain abrasion can be caused to the surface of the pump shaft after long-term operation.

Disclosure of Invention

The utility model discloses to above-mentioned problem, provide one kind and need not to install footstep bearing, reduce the manufacturing cost and the maintenance cost's of pump multistage centrifugal pump by a wide margin.

For realizing the above purpose of the utility model, the utility model discloses a no footstep bearing multistage centrifugal pump, including the pump shaft, the department of spitting section that is located the pump on the pump shaft is provided with the balance plate, and the balance plate side is provided with the throttle bush, and the balance plate is balanced cover, its characterized in that outward: the balance disc comprises a disc body and a balance shaft sleeve; the disc body is provided with a friction top surface relative to the throttling bush; gaps are arranged between the disc body and the balance sleeve and between the disc body and the throttling bush.

As an optimized proposal of the utility model, a tooth-shaped adjusting pad is arranged between the disk body and the balance shaft sleeve.

As another preferred scheme of the utility model, the pump shaft tip is the sliding bearing axle, and the sliding bearing axle is the lubrication chamber outward, is provided with the oil slinger on the sliding bearing axle, and the contact surface of oil slinger and pump shaft is provided with the rectangle recess, is provided with in the rectangle recess with pump shaft complex polytetrafluoroethylene protective sheath.

As a third preferred scheme of the utility model, be provided with the end cover corresponding to the tip of pump shaft, be provided with holding screw on the end cover.

Furthermore, the set screw is a long cylindrical spherical end set screw.

Further, the loosening rotation direction of the set screw is consistent with the normal rotation direction of the pump shaft.

The beneficial effects of the utility model.

1. The utility model discloses cancel former thrust bearing body, thrust ball bearing and accessory part, suction side and spit the side and adopt same bearing body, reduction in production cost and maintenance cost.

2. The utility model discloses with former integral balance plate split do: the balance shaft sleeve and the disc body properly bulge the rear side of the balance disc to form a new axial friction pair with the throttling bush, so that the rotor component is prevented from moving backwards. The hardness difference between the balance disc and the balance sleeve and between the balance disc and the throttling bush is improved, and grinding faults are prevented.

3. The utility model discloses improve the structure of oil slinger, inlay non-metallic material polytetrafluoroethylene at the internal surface with the pump shaft contact, its hardness is far less than the pump shaft, realizes only wearing and tearing oil slinger protection pump shaft.

4. When the pump is in a long-distance transportation state, no liquid medium exists in the pump, the balance disc does not work, and in order to prevent the rotor part from being damaged due to dry friction of matched parts caused by forward and backward physical movement, a square head long circular column spherical end fastening screw is additionally arranged on the end cover of the discharge side and is tightly pressed with the end face of the pump shaft. Before the pump starts to operate, the set screw is loosened. Simultaneously, in order to prevent before the start-up operation, operating personnel forget to loosen this holding screw, the direction of rotation design that loosens the screw is unanimous with the normal direction of rotation of pump shaft, realizes that the pump shaft rotation can drive and loosen this holding screw.

Drawings

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

Fig. 2 is an enlarged view of a portion I of fig. 1.

Fig. 3 is an enlarged view of a portion II of fig. 1.

Fig. 4 is a schematic structural view of a conventional multistage centrifugal pump.

Fig. 5 is a partially enlarged view of fig. 4.

In the attached drawing, 1 is a pump shaft, 2 is a suction section, 3 is a middle section, 4 is a discharge section, 5 is a sliding bearing bush, 6 is a set screw, 7 is an oil slinger, 8 is a balance sleeve, 9 is a balance shaft sleeve, 10 is a tooth-shaped adjusting pad, 11 is a disc body, 12 is a throttling bush, 13 is a friction top surface, and 14 is an end cover.

Detailed Description

The utility model discloses a no footstep bearing multistage centrifugal pump, including

pump shaft

1, 4 departments of the section of spitting out that lie in the pump on the pump shaft 1 are provided with the balance plate, and the balance plate side is provided with throttle bush 12, and the balance plate is balance cover 8, its characterized in that outward: the balance disc comprises a disc body 11 and a balance shaft sleeve 9; the disc body 11 is provided with a friction top surface 13 opposite to the throttling bush 12; gaps are arranged between the disc body 11 and the balance sleeve 8 and the throttling bush 12.

As a preferred scheme of the present invention, a tooth-shaped adjusting pad 10 is disposed between the tray body 11 and the balance shaft sleeve 9.

As another preferred scheme of the utility model, 1 tip of pump shaft is sliding bearing shell 5, and sliding bearing shell 5 is the lubricated chamber outward, is provided with oil slinger 7 on the sliding bearing shell 5, and oil slinger 7 and pump shaft 1's contact surface are provided with the rectangle recess, are provided with in the rectangle recess with the 1 complex polytetrafluoroethylene protective sheath of pump shaft.

As a third preferred embodiment of the present invention, an end cover 14 is provided corresponding to the end of the pump shaft 1, and a set screw 6 is provided on the end cover 14.

Further, the set screw 6 is a long cylindrical spherical end set screw 6.

Further, the rotation direction of the set screw 6 is consistent with the normal rotation direction of the pump shaft 1.

The gap between the disc body 11 and the balance sleeve 8 and the throttling bush 12 is set to be 0.3-0.4 mm as the best, and can be adjusted through the tooth-shaped adjusting pad 10.

The prime motor drives the pump shaft 1 to rotate and drives the impeller to rotate. The liquid medium enters from the suction section 2, passes through the impeller, the guide vane and the middle section and gradually enters the discharge section 4. At this time, the pressure of the liquid medium rises, and simultaneously enters a small axial gap formed by the balance shaft sleeve 9 and the balance sleeve 8 and then enters a small radial gap formed by the balance sleeve 8 and the disc body 11. Under the action of the pressure liquid medium, the thrust rotor component integrally moves backwards. The friction top surface 13 on the rear side of the disc 11 is provided with a slight radial clearance from the throttle bushing 12. The disc body 11 moves, the disc body 11 is instantaneously contacted with the throttling bush 12, the rotor component is prevented from moving backwards continuously, at the moment, the axial clearance between the front side of the disc body 11 and the balancing sleeve 8 is enlarged, and the pressure of the balancing chamber is increased. According to the working principle of the balance disc, the pressure rise of the balance chamber pushes the rotor component to move forwards, the rotor component is ensured to swing back and forth in a preset clearance, and other parts in the pump are protected. The heat generated by the instantaneous contact friction of the balance disc and the throttling bush 12 and the balance disc and the balance sleeve 8 is discharged by the circulation of the liquid medium.

When the mechanical seal is overhauled, maintained and replaced, the end cover 14 is firstly disassembled, and the sliding bearing bush 5 is of a split structure and can be easily moved away, so that the mechanical seal can be overhauled, maintained and replaced quickly.

When the balance disc is worn, the tooth-shaped adjusting pad adjusts the axial clearance between the disc body 11 and the throttling bush 12 according to the wearing condition.

It should be understood that the above detailed description of the present invention is only for illustrating the present invention and is not limited by the technical solutions described in the embodiments of the present invention, and those skilled in the art should understand that the present invention can still be modified or equivalently replaced to achieve the same technical effects; as long as the use requirement is satisfied, the utility model is within the protection scope.

Claims

1. The utility model provides a no footstep bearing multistage centrifugal pump, includes pump shaft (1), lies in on pump shaft (1) and spits section (4) department of pump and be provided with the balance plate, and balance plate side is provided with throttle bush (12), and the balance plate is outer for balanced cover (8), its characterized in that: the balance disc comprises a disc body (11) and a balance shaft sleeve (9); the disc body (11) is provided with a friction top surface (13) relative to the throttling bush (12); gaps are arranged between the disc body (11) and the balance sleeve (8) and the throttling bush (12).

2. The thrust-bearing-free multistage centrifugal pump according to claim 1, characterized in that: a tooth-shaped adjusting pad (10) is arranged between the disc body (11) and the balance shaft sleeve (9).

3. The thrust-bearing-free multistage centrifugal pump according to claim 1, characterized in that: the end part of the pump shaft (1) is provided with a sliding bearing bush (5), the outside of the sliding bearing bush (5) is provided with a lubricating chamber, an oil slinger (7) is arranged on the sliding bearing bush (5), the contact surface of the oil slinger (7) and the pump shaft (1) is provided with a rectangular groove, and a polytetrafluoroethylene protective sleeve matched with the pump shaft (1) is arranged in the rectangular groove.

4. The thrust-bearing-free multistage centrifugal pump according to claim 1, characterized in that: an end cover (14) is arranged corresponding to the end part of the pump shaft (1), and a set screw (6) is arranged on the end cover (14).

5. The thrust bearing-less multistage centrifugal pump according to claim 4, wherein: the set screw (6) is a long cylindrical spherical end set screw (6).

6. The thrust bearing-less multistage centrifugal pump according to claim 4, wherein: the loosening rotation direction of the set screw (6) is consistent with the normal rotation direction of the pump shaft (1).