CN110685949A

CN110685949A - Ceramic thrust bearing for engineering plastic well pump

Info

Publication number: CN110685949A
Application number: CN201910687370.XA
Authority: CN
Inventors: 王万宏; 韩晨; 周岭
Original assignee: Nanjing River Water Pump Co Ltd
Current assignee: Nanjing River Water Pump Co Ltd
Priority date: 2019-07-27
Filing date: 2019-07-27
Publication date: 2020-01-14

Abstract

The invention relates to a ceramic thrust bearing for an engineering plastic well pump, which is formed by ceramic sintering, and is respectively embedded in an inner hole of an engineering plastic guide vane and the lower end of an impeller hub to jointly pair into a sliding thrust bearing to bear the axial force of an impeller. The upper end of the top of the guide vane ceramic bearing insert and the lower end of the impeller hub ceramic bearing insert form a lower thrust sliding bearing which bears the downward axial force generated when the impeller operates; the top end of the hub on the impeller rear cover plate and the lower plane of the plastic guide vane ceramic bearing insert form an upper thrust sliding bearing to bear the upward axial force of the impeller when the well pump is started, and meanwhile, the inner hole of the plastic guide vane inner hole ceramic bearing insert is used as a radial bearing of the pump shaft, so that the pump shaft always runs on the central line of the water pump. Because the ceramic material has good wear resistance, the ceramic material can form a good friction pair with engineering plastics and ceramics, reduce the wear and prolong the service life of a well pump. Meanwhile, the ceramic material is low in cost and easy to manufacture.

Description

Ceramic thrust bearing for engineering plastic well pump

Technical Field

The invention relates to a ceramic thrust bearing for an engineering plastic well pump, in particular to a novel ceramic thrust bearing used as a sliding thrust bearing in an engineering plastic well pump adopting a floating impeller.

Background

It is well known that the overcoming of the axial force of the impeller is a critical issue that is not negligible in the design of well pumps, and especially today more and more well pumps use engineering plastics for the manufacture of the impeller and guide vanes, the axial force becomes an important factor affecting the life of the well pump. Under general conditions, a thrust bearing of a matched motor is used for bearing axial force, but when the number of stages is large, the axial force easily exceeds the bearing capacity of the motor bearing, so that the motor is damaged, and the service life of a product is influenced. Currently, floating impellers are widely used to balance axial forces. And a friction pair formed by the impeller and the end surface of the guide vane is utilized to perform self-balancing in each stage, so that the axial force on the pump shaft is reduced. The invention patent bearing insert embedded in the inner hole of plastic guide shell of engineering plastic well pump (patent number 201010003057.9) also solves the problem of axial force of floating impeller. But the friction pair bearing the axial force is plastic to stainless steel, and the service life is not too long when the rotating speed is high and the linear speed is high.

Disclosure of Invention

In order to further solve the problem of service life caused by the axial force of the engineering plastic well pump, the invention adopts a mode of installing novel ceramic bearings at the inner hole part of the plastic guide vane and the lower end of the impeller hub, thereby forming a ceramic-to-ceramic friction pair and well solving the problems.

The technical scheme of the invention is as follows:

inlay a bearing spare respectively at the plastics stator hole position of engineering plastics well pump and plastics impeller wheel hub lower extreme, this inserts adopt ceramic sintering shaping, and two inserts pair into axial thrust slide bearing jointly, and its innovation point lies in:

1. the bearing insert positioned in the inner hole of the plastic guide vane is in a circular ring step in the whole shape, the circular ring at the upper part is smaller, the circular ring at the lower part is larger, the part of the circular ring at the lower part, which is larger than the circular ring at the upper part, is in a sawtooth shape, 8 sawteeth are distributed in an annular shape at intervals of 45 degrees, and the bearing insert and the plastic guide vane are firmly connected together after injection molding;

2. after the bearing insert and the plastic guide vane are integrated, the upper plane of the bearing insert exposed outside the plastic is a bearing surface for bearing the downward axial force of the impeller, the lower plane of the bearing insert exposed outside the plastic is a bearing surface for bearing the upward axial force of the impeller, and an inner hole of the bearing insert can be used as a radial bearing;

3. the lower part of the bearing insert at the lower end of the plastic impeller hub is provided with a circular ring, the upper part of the bearing insert is annularly distributed with 8 bosses at intervals of 45 degrees, after the plastic impeller is injected, the bosses at the upper part are embedded into the plastic of the impeller hub to play a role in positioning and fastening, the bottom surface of the circular ring at the lower part is a thrust surface of a thrust bearing, and the bottom surface of the circular ring at the lower part and the upper plane of the bearing insert at the inner hole part of the plastic guide vane are matched together to form a sliding thrust bearing;

4. the top end of the hub on the rear cover plate of the plastic impeller and the lower plane of the bearing insert at the inner hole part of the plastic guide vane are matched together to form a sliding thrust bearing for bearing the upward axial force of the impeller.

The invention has the advantages that the lower production cost realizes higher bearing performance, overcomes the downward axial force and the upward axial force of the impeller, reduces the abrasion of the impeller hub, and effectively improves the service life and the reliability of the well pump.

Drawings

The invention is further illustrated with reference to the following figures and examples.

FIG. 1 is a diagrammatic view of one embodiment of the present invention on a multi-stage well pump;

FIG. 2 is an enlarged view of a plastic vane in an embodiment of the present invention;

FIG. 3 is an enlarged view of a plastic vane bearing piece in an embodiment of the invention;

FIG. 4 is an enlarged view of a plastic impeller in an embodiment of the present invention;

fig. 5 is an enlarged view of a plastic impeller hub-bearing member in an embodiment of the present invention.

In the figure: 1. the plastic guide vane comprises a plastic impeller, 2 plastic guide vanes, 3 bearing inserts in inner hole parts of the plastic guide vanes, 4 pump shafts, 5 bearing inserts at the lower end of a hub of the plastic impeller, 6 top ends of the hub of the impeller, 7 lower ends of bearing parts of the hub of the impeller, 8 lower planes of the bearing inserts in inner hole parts of the guide vanes, 9 top planes of the bearing pieces in inner holes of the guide vanes, and 10 inner holes of the bearing inserts in inner hole parts of the guide vanes.

Detailed Description

Fig. 1 is an embodiment of the present invention, which is part of a multi-stage well pump using plastic impellers 1 and plastic vanes 2, the impellers 1 being slidable on pump shafts 4, commonly referred to as floating impeller structures. When the water pump is started, the impeller 1 can float upwards under the action of water thrust, the hub top end 6 on the impeller rear cover plate can touch the lower plane 8 of the bearing insert at the inner hole part of the plastic guide vane, and the upward axial force is very small and short in duration, so that the sliding bearing consisting of the plastic hub top end 6 and the lower plane 8 of the ceramic bearing insert can bear the upward axial force.

When the water pump normally operates, the axial force of the impeller is downward, the impeller 1 can float downward under the action of the axial force, the lower end 7 of the bearing insert of the impeller hub can be contacted with the top plane 9 of the bearing insert at the inner hole part of the plastic guide vane, and the bearing insert 3 at the inner hole part of the plastic guide vane and the bearing insert 5 at the lower end of the plastic impeller hub are both made of ceramic materials and have strong wear resistance, so that the downward axial force of the impeller can be borne, and the abrasion life is long.

The inner hole 10 of the bearing insert at the inner hole part of the guide vane can also be used as a radial bearing of the pump shaft 4, so that the pump shaft always runs on the central line of the water pump.

The bearing insert in the inner hole of the plastic guide vane is in a circular ring step in the whole shape, the circular ring at the upper part is smaller, the circular ring at the lower part is larger, the part of the circular ring at the lower part, which is larger than the circular ring at the upper part, is in a sawtooth shape, 8 sawteeth are distributed in an annular shape at intervals of 45 degrees (as shown in figure 3), and the bearing insert and the plastic guide vane are firmly connected together after injection molding (as shown in figure 2).

The lower part of the bearing insert at the lower end of the plastic impeller hub is a circular ring, the upper part is annularly distributed by 8 bosses at intervals of 45 degrees (as shown in figure 5), and after the plastic impeller is injected, the bosses at the upper part are embedded into the plastic of the impeller hub, so that the bearing insert and the plastic impeller are firmly connected together (as shown in figure 4).

The ceramic bearing has simple structure, is easy to sinter and form, realizes higher bearing performance by using lower production cost, overcomes the downward axial force and the upward axial force of the impeller, reduces the abrasion of the impeller hub, and effectively improves the service life and the reliability of a well pump.

Claims

1. A ceramic thrust bearing for an engineering plastic well pump is formed by ceramic sintering, and is respectively embedded in an inner hole of an engineering plastic guide vane and the lower end of an impeller hub to jointly pair into a sliding thrust bearing so as to bear the axial force of an impeller. The method is characterized in that: the bearing insert positioned in the inner hole of the plastic guide vane is in a circular ring step in the whole shape, the circular ring at the upper part is smaller, the circular ring at the lower part is larger, the part of the circular ring at the lower part, which is larger than the circular ring at the upper part, is in a sawtooth shape, the 8 sawtooth intervals are distributed in an annular shape at 45 degrees, the bearing insert and the plastic guide vane are firmly connected together after injection molding, and the whole upper plane, the whole inner hole and one part of the lower plane of the ceramic bearing are exposed outside plastic. The lower part of the bearing insert at the lower end of the plastic impeller hub is provided with a circular ring, the upper part of the bearing insert is annularly distributed by 8 bosses at intervals of 45 degrees, after the plastic impeller is molded, the bosses at the upper part are embedded into the plastic of the impeller hub to play a role in positioning and fastening, the bottom surface of the circular ring at the lower part is a thrust surface of a thrust bearing, and the thrust surface and the upper plane of the bearing insert at the inner hole part of the plastic guide vane are jointly paired to form a sliding thrust bearing for bearing the downward axial force of the.

2. The ceramic thrust bearing for an engineering plastic well pump as claimed in claim 1, wherein the top end of the hub on the back cover plate of the plastic impeller and the lower plane of the bearing insert at the inner hole part of the plastic guide vane are matched together to form a sliding thrust bearing for bearing the upward axial force of the impeller.

3. The ceramic thrust bearing for the engineering plastic well pump as claimed in claim 1, wherein the inner hole of the ceramic bearing insert of the inner hole of the plastic guide vane can be used as a radial bearing of the pump shaft.