FOR SUBMERSIBLE PUMP AND MOTOR

FIELD OF THE INVENTION

[0001] The invention relates to a thrust bearing and more particularly it relates to a water lubricated silicon carbide thrust bearing for submersible pump and motor configured on plurality of tilting segments.

BACKGROUND OF THE INVENTION

[0002] Submersible pump assemblies are widely used in connection with wells for use in irrigation or residential systems or other well applications. Generally, submersible pump assemblies include an axial discharge pump which is connected to a discharge pipe and to a submersible motor assembly. The motor assembly is carried coaxially below the pump with a rotor shaft being coupled to a pump impeller shaft. In such arrangement, the rotor shaft carries a substantial axial load due to the weight of the rotor as well as hydraulic loading from the internal components of the pump. In addition, substantial radial loading is often experienced by the motor assembly as a result of the torque required to pump the column of water through the discharge pipe.

[0003] The environment in which submersible pump assemblies operate is often quite harsh. The use of thrust bearings to carry the imposed load on a substantially vertical shaft is well known in the art. As imposed loads on the shaft are increased, it becomes necessary to construct large thrust bearings, which require more space. Thus, housings in which the shaft is journaled must be larger in diameter to house the shaft-thrust bearing assembly.

[0004] A Patent Number CA3070385 (Al) describes an electric submersible motor thrust bearing system which includes a thrust bearing assembly carrying a thrust of an electric submersible motor, the thrust bearing assembly including a split ring secured around a shaft of the electric submersible motor inward of a rotatable thrust runner, the rotatable thrust runner is coupled around an outer diameter of the split ring which is mated above a non-rotatable thrust bearing, the rotatable thrust runner serving as a barrier to radial expansion of the split ring, a lock ring secured to the thrust runner by a threaded connection, at least a portion of the lock ring above the split ring and at least a portion of the thrust runner below the split ring, and the threaded connection securing the split ring axially between the lock ring and the thrust runner.

[0005] However, during operation, the submersible pump and motor are prone to handle contaminated water whereas inspite of mechanical or oil seals, surrounding water with sand, salt, minerals and coal enters the submersible motor or pump therein which causes the major issue of motor or pump failure thereby causing damage to the concerned parts of the thrust bearing assembly. Further, the high thrust load requirements are also increasing day by day that cause failure to the conventional thrust bearing.

[0006] Therefore, a need exists for a water lubricated thrust bearing that is capable to efficiently work in such media without causing failure to the pump and the thrust assembly. OBTECT OF THE INVENTION

[0007] The main object of the present invention is to provide a water lubricated silicon carbide thrust bearing which circumvents the interruption of contaminated water from the surroundings to the assembly whereby both the tilting segments and thrust rotating plate contact area are made from silicon carbide.

[0008] Another object of the present invention is to provide a water lubricated silicon carbide thrust bearing for submersible pump and motor incorporated with water path and micro pits formed on the thrust segments providing appropriate water flow in the said assembly and leading to efficient lubrication therein.

[0009] Yet another object of the invention is to provide a thrust bearing that can work efficiently at higher thrust loads even when surrounded by cold, hot, contaminated water involving abrasive materials like sand, minerals, coal and sand pertaining to sea water also in addition to plain clear cold water.

[0010] Yet another object of the invention is to provide a thrust bearing which is easy to operate, simple in construction and an economical solution which particularly focuses on the loosely connected tilting segments with bearing base.

[0011] Yet another object of the invention is to provide an easy film formation technique by providing smooth entry of water to the bearing segments for better functioning of the thrust bearing. [0012] Yet another object of the invention is to incorporate water path and micro pits to form pulling force of the lubricant water and to generate additional lubrication through silicic acid.

SUMMARY OF THE INVENTION [0013] The present invention relates to a water lubricated silicon carbide thrust bearing for submersible pump and motor. More particularly, it comprises two main bearing parts tilting segments and a thrust rotating plate made of silicon carbide which are connected to each other. The said bearing parts are installed in the submersible assembly which is prone to handle abrasive water, hot water, water with sand, phosphorus, salt, coal and heavy minerals. The plurality of silicon carbide tilting segments are arranged to form a circular array and are mounted on a pivot base made from metallic materials. The arrangement is constructed in a specific manner that the tilting segments remain loosely connected to the base for ease of installation. The thrust plate is mounted specifically on drive rotor and is drivable with the rotor. The circular array of tilting segments and thrust plate are mounted on drive rotor and are on the same axis. The tilting segments are mounted over with the micro pits providing an efficient lubrication and the working hills provide water paths for additional circulation.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] It should be noted that the figures are not drawn to scale and that elements of similar structures or functions are generally represented by like reference numerals for illustrative purposes throughout the figures. It also should be noted that the figures are only intended to facilitate the description of the preferred embodiments. The figures do not illustrate every aspect of the described embodiments and do not limit the scope of the present disclosure.

[0015] Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the present embodiment when taken in conjunction with the accompanying drawings.

[0016] Figure 1 illustrates the plan view of a thrust bearing assembly showing the detailed structure of stationary component of the bearing which specifically includes the tilting segments and thrust base. [0017] Figure 2 illustrates the plan view of the tilting segment showing the gripping gap therein.

[0018] Figure 3 illustrates the side view of the tilting segment showing the gripping gap therein.

[0019] Figure 4 illustrates the exploded view of the thrust bearing assembly.

[0020] Figure 5 illustrates the side view of the thrust bearing with outer pivot formed on the thrust bearing base.

[0021] Figure 6 illustrates the side view of the thrust bearing with centre inner pivot with concave or convex shape. [0022] Figure 7 illustrates the plan view showing micro pits formed on the segments.

[0023] Figure 8 illustrates the plan view showing hills and water tunnels for circulation of water formed on the segments. [0024] It should be noted that the figures are not drawn to scale and that elements of similar structures or functions are generally represented by like reference numerals for illustrative purposes throughout the figures. It also should be noted that the figures are only intended to facilitate the description of the preferred embodiments. The figures do not illustrate every aspect of the described embodiments and do not limit the scope of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

[0025] Before explaining the present invention in detail, it is to be understood that the invention is not limited in its application to the details of the construction and arrangement of parts illustrated in the accompany drawings. The invention is capable of other embodiments, as depicted in different figures as described above and of being practiced or carried out in a variety of ways. It is to be understood that the phraseology and terminology employed herein is for the purpose of description and not of limitation.

[0026] It is to be noted that the invention is used as a part or sub-assembly of submersible pump and motor so where the word "drive rotor" or "drive shaft" are used, it is connected to the thrust rotating plate and the "drive rotor" or "drive shaft" are not to be considered under scope of invention.

[0027] The present disclosure gives an overview of a water lubricated thrust bearing for submersible pump and motor bearing the tilting segments which circumvent the contaminated water being interrupted from the surroundings by the purposely arrangement of the tilting segments and rotating thrust plate contact area which are made from silicon carbide incorporated in the submersible motor, submersible pump or motor boat propelling system.

[0028] Now, as shown in Fig. 1 illustrates the isometric view of a water lubricated silicon carbide thrust bearing for submersible pump and motor. Now, the thrust bearing (1) as shown in FIG. 1 comprises a thrust bearing tilting base (3) made from metals like stainless steel, carbon steel, cast iron or nonferrous material, a plurality of silicon carbide tilting segments (2) arranged on said thrust bearing base (3) and a rotating thrust plate (not shown) containing silicon carbide rigidly clenched by thrust bearing base (3) which rotate axially aligned to the plurality of the tilting segments (2) arranged to form an array in respect to the axis of rotating thrust plate. This whole arrangement is mounted in a water filled cage which takes care of the contaminated water interrupting from surroundings as both stationary segments and rotating thrust plate contact area are made of silicon carbide.

[0029] The each tilting segment (2) is mounted over the thrust bearing base (3) includes cage (s) formed by L shaped protuberances (16) located proximal to the central shaft hole (17) and supporting members (18) on the periphery of the thrust bearing base (3) to accommodate the tilting segments (2) appropriately.

[0030] Further, the each tilting segment (2) is mounted upon the thrust bearing base (3) which may be organized as a flat or tilting shaped arrangement made from metals like stainless steel, carbon steel, cast iron or non ferrous material thereof. [0031] Furthermore, said rotating thrust plate is mounted on drive rotor and is drivable with the rotor. This plate has two components one of silicon carbide and another made of cast iron, carbon steel, stainless steel or nonferrous material. The circular array of segments and the plate mounted on drive rotor are on the same axis.

[0032] Now referring to Fig. 2 and Fig. 3, each tilting segment (2) is configured to have gripper grooves (8) on its both sides which facilitate the tilting segment (2) to get appropriately positioned by arrangement of lock. Further, each tilting segment (2) is configured to have a pivot (9) formed on the bottom side of tilting segment (2) for creating proper swiveling on the thrust bearing base (3). Moreover, radius (10) is to be considered as a slope arrangement which is more specifically curved from top leading to ensure appropriate water flow intake further forming a film therein.

[0033] Now, Fig. 4 illustrates the mounting of tilting segment (2) on the thrust bearing base (3) whereby each tilting segment (2) is arranged appropriately and mounted specifically on the said thrust bearing base (3). The fastening means (4) are partially received within the gripper grooves (8) formed on sides of the each tilting segment (2). The said tilting segments (2) are placed on an integrated soft or hard based seat (14) of the thrust bearing base (3). Further, for providing a loose grip, fastening means (4) like screws, bolts, nuts etc. are placed upon the provided holes (15) of the thrust bearing base (3) for locking arrangement therein.

[0034] According to another embodiment as shown in the Figure 4 above, the hardened pins are incorporated made of materials like silicon carbide, tungsten carbide, other ceramic at the place of seat (14) mounted over with the tilting segment (2) which are hard in nature and reduces the wear and tear of the thrust bearing base (3).

[0035] Further, tilting segments (2) may be loosely held by fastening means (4) configuring arrangement such that it can form taper when in application and forms a constant film therein.

[0036] Further, as shown in Fig. 5 and 6, the thrust bearing base (3) is configured to have an outer pivot (6) at bottom that fits in the machine even if rotating shaft is extended for further functions. Further, the thrust bearing base (3) is also configured to have a center pivot (7) at bottom with concave or convex shape at bottom side to segment-back to fit in the machine even if rotating shaft is extended for further functions.

[0037] According to another embodiment, as shown in Fig. 7, each tilting segment (2) is provided with plurality of micro pits (11) formed on the top surface of tilting segment (5) thereof. This configuration forms additional lubrication known as silicic acid which involves the formation of low pressure zones created by the micro pits (11) and reaction of silicon carbide with water which is termed as tribo chemical water resulting to effective lubrication properties.

[0038] According to another embodiment as shown in Fig. 8, each tilting segment (2) is incorporated with a representation of water path (13) which leaves behind actual working hills (12) formed on the top surface of tilting segment (5) which is more facilitated for the large bearings where the segment size is more.

[0039] The said thrust bearing assembly involves a combination of silicon carbide made the tilting segments (2) and the thrust rotating plate also made of silicon carbide which is backed by a base (3) of metal rotating axially aligned to the plurality of tilting segments (2) arranged to form an array in respect to the axis of the rotating thrust plate which circumvents the contaminated water being interrupted from the surroundings of the submersible motor, submersible pump or motor boat propelling system.

[0040] The invention has been explained in relation to specific embodiment. It is inferred that the foregoing description is only illustrative of the present invention and it is not intended that the invention be limited or restrictive thereto. Many other specific embodiments of the present invention will be apparent to one skilled in the art from the foregoing disclosure.

[0041] All substitution, alterations and modification of the present invention which come within the scope of the following claims are to which the present invention is readily susceptible without departing from the spirit of the invention. The scope of the invention should therefore be determined not with reference to the above description but should be determined with reference to appended claims along with full scope of equivalents to which such claims are entitled.

List of Reference Numerals:

1. Thrust bearing (1)

2. Tilting segments (2)

3. Thrust bearing base (3)

4. Fastening means (4)

5. Top surface of tilting segment (5)

6. Outer pivot (6)

7. Center pivot (7)

8. Gripper grooves (8)

9. Pivot (9)

10. Radius (10)

11. Micro pits (11)

12. Working hills (12)

13. Water path (13)

14. Seat (14)

15. Holes (15)

16. L shaped protuberances (16)

17. Central shaft hole (17)

18. Supporting members (18)