WO2008017210A1

WO2008017210A1 - A mechanical sealing device of motor direct-drive screw pump

Info

Publication number: WO2008017210A1
Application number: PCT/CN2006/001966
Authority: WO
Inventors: Jun Liu; Yongjian Tang; Hengli Cong; Songbo Gou
Original assignee: Jun Liu; Yongjian Tang; Hengli Cong
Priority date: 2006-08-04
Filing date: 2006-08-04
Publication date: 2008-02-14

Abstract

A mechanical sealing device of a motor direct-drive screw pump comprises a polished rod (3), a polished rod clamp seat (13), a fixed sleeve (9), a dynamic ring (4), a static ring (5), a alignment bearing (8) and a hollow drive shaft (17). The space between the polished rod (3) and the polished rod clamp seat (13) is filled with stuffing (11). The polished rod (3) passes through the fixed sleeve (9). A rotary part is formed from the polished rod (3), the polished rod clamp seat (13), the hollow drive shaft (17) and the dynamic ring (4) attached to the fixed sleeve (9). A leaking hole (15) and a terminal strand (16) are provided on the side wall of the hollow drive shaft. The polished rod clamp seat is attached to the hollow drive shaft by a drive key (6). A static part is formed from the fixed sleeve and the static ring. The structure of the sealing device is simple and the sealing device is easy to be maintained.

Description

Motor directly drives screw pump mechanical seal device

The invention belongs to a ground oil extraction screw pump sealing device, in particular to a motor direct drive screw pump mechanical sealing device.

Background technique

At present, the traditional ground oil extraction screw pump uses a common asynchronous motor to drive through the belt, which drives the gear box, and the gear box drives the polished rod of the screw pump to perform a rotary motion. This kind of oil pump is equipped with a mechanical seal device only for a few years. The utility model patent ZL03240206.6 upper mechanical seal screw pump drive device describes the mechanical seal device installed on the upper part of the screw pump oil outlet. After careful research, it is found that there are some areas for improvement of existing mechanical seals, mainly in the following two points:

1. Since the mechanical seal is installed on the upper part of the screw pump outlet, there will be gas in the seal chamber. The liquid in the system line does not flow into the sealed chamber and does not function as a lubricant. The moving and stationary rings are damaged by the lack of dry grinding of the liquid lubricating medium.

2. When the speed of the polished rod is high (for example, about 400 rpm), the dynamic and static rings in the mechanical seal will generate more heat due to the high-speed rotation, and will be subject to the specific structure of the slick oil pump, and the mechanical seal will be static and static. The heat generated by the ring can only be dissipated by the natural cooling of the air. When the heat is high, the rubber ring in the mechanical seal will be degraded, and the dynamic and static ring wear will be intensified, which will reduce the reliability of the sealing device.

For the motor directly driven screw pump device required by CN200510042122. 8, the same mechanical sealing device is also needed to solve the dynamic sealing problem during the rotation of the direct drive screw pump of the motor, and overcome the dynamic and static mechanical seal device on the existing conventional screw pump. Lubrication problems and heat dissipation problems between the rings. Mechanical seals currently used for direct drive screw pumps for electric motors have not been used or reported.

Summary of the invention

SUMMARY OF THE INVENTION The object of the present invention is to provide a mechanical seal device for directly driving a screw pump of a motor to solve the problem of dynamic sealing during the rotation of the motor directly driving the screw pump.

The motor directly drives the screw pump mechanical sealing device of the invention, comprising the optical rod 3, the polished rod holder 13, the fixed sleeve 9, the moving ring 4, the stationary ring 5, the positioning bearing 8, the sealing rod between the polished rod 3 and the polished rod holder 13 11 is fixed by filling, the static ring 4 is fixed on the fixing sleeve by the adjusting nut 2, the polished rod 3 passes through the fixing sleeve 9, and the O-ring 14 is arranged between the moving ring 4 and the stationary ring 5 on the fixing sleeve 9. The stationary ring 5 on the fixed sleeve 9 and the positioning bearing 8 have a skeleton seal 7 , and further comprises a motor hollow transmission shaft 17; a polished rod 3, a polished rod holder 13 , a motor hollow transmission shaft 17 , and a fixed sleeve 9 The moving ring 4 together constitutes a rotating part; the side wall of the motor hollow transmission shaft is provided with a leakage hole 15 and a top wire 16, and the polished rod holder 10 and the motor hollow transmission The shafts 17 are connected by a transmission key 6, and the fixed sleeve 9 and the stationary ring 5 together form a stationary portion. The invention successfully solves the problem of dynamic sealing during the rotation process of the direct drive screw pump of the motor by installing the mechanical sealing device on the hollow shaft of the motor directly driving the screw pump.

The motor of the invention directly drives the mechanical seal device of the screw pump, and the gasket 10 is arranged under the sealing packing, and the packing pressure cap 20 is arranged on the sealing packing.

The motor of the present invention directly drives the mechanical pumping device of the screw pump, and a venting hole 12 is disposed on the outer casing, and the venting hole 12-end communicates with the mechanical sealing cavity surrounded by the optical rod holder 13 and the motor hollow transmission shaft 17, and the other end is The air above the mechanical seal is in communication, and the end of the air that communicates with the air above the seal is provided with a switchable valve 18.

The motor of the present invention directly drives the mechanical seal device of the screw pump, and the annular heat sink 1 is sleeved on the surface of the optical rod clip seat, and is fixedly connected with the optical rod clip seat 13. The heat sink 1 is made of metal, and the outer ring of the heat sink is provided. Uniformly distributed helical protrusions 19. The motor of the invention directly drives the mechanical seal device of the screw pump, and is equipped with a gasket under the sealing packing, and a packing pressure cap is arranged on the sealing packing.

The motor of the present invention directly drives the screw pump mechanical seal device in that the heat sink 1 is made of metal aluminum.

The motor of the present invention directly drives the mechanical seal device of the screw pump, and the spiral protrusion of the outer ring of the fin is 2 to 30 rows.

The thickness of the spiral protrusion of the outer ring of the fin is 0. 5cm - 10cm. Beneficial effects:

The invention directly fixes the mechanical sealing device on the motor drive shaft of the direct drive screw pump (as shown in Fig. 1). The advantage of this structure is that the structure is simple and the mechanical seal device is convenient to replace.

The invention is provided with a venting hole in the upper part of the mechanical seal chamber. When the venting port is opened after each installation and before starting the pump, the line pressure in the system will cause the crude oil to enter the sealed chamber, drain the air in the chamber, and then close the vent. This part of the crude oil in the sealed chamber can be used as a lubricant for the static and static rings to prevent the moving and static rings from being worn and damaged by each other. Extend the service life and increase the reliability of mechanical seals.

The invention adds an aluminum heat sink to the outside of the mechanical seal cavity. The heat sink is helical, so that as the speed increases, the spiral heat sink is more capable of dissipating heat. The radiator can timely dissipate the heat generated by the mechanical seal and the static ring friction, and prolong the service life of the rubber 0 in the mechanical seal device. DRAWINGS Figure 1 Mechanical seal with heat sink and venting holes

Figure 2 Mechanical seal with venting holes

Figure 3 Mechanical seal with heat sink

Figure 4 Mechanical seal with packing caps, gaskets, fins and venting holes

Figure 5 heat sink outline drawing

1. Heat sink 2. Adjusting nut 3. Light rod 4. Moving ring 5. Static ring 6. Transmission key 7. Skeleton seal 8. Positioning bearing 9. Fixing sleeve 10. Spacer 11. Sealing packing 12. Venting hole 13 Light rod clip seat 14. 0-shaped seal ring 15. Leak hole 16. Top wire 17. Motor hollow drive shaft 18. Vent port valve 19. Spiral protrusion on the radiator 20. Packing cap

detailed description:

Example 1 : (See Figure 3)

The motor shaft that directly drives the oil extraction screw pump is made hollow and the upper part is thickened, which is convenient for installing the mechanical seal device. The light rod 3 is passed through the fixing sleeve 9 of the mechanical sealing device, and the O-ring 14 is arranged between the moving ring 4 on the fixing sleeve 9 and the stationary ring 5, and the fixing sleeve 9 is connected to the direct driving screw through the positioning bearing 8. On the motor hollow drive shaft 17 of the pump, there is a skeleton seal 7 between the stationary ring 5 on the fixed sleeve 9 and the positioning bearing 8, and the drive shaft 6 is connected between the outer casing 13 and the hollow shaft 17 of the motor, and the side wall of the hollow shaft of the motor A leak hole 15 and a top wire 16 are provided. The stationary ring 5 and the motor hollow drive shaft 17 together form a stationary portion. The polished rod 3 and the polished rod holder 10 are sealed and fixed by the sealing packing 11, and the polished rod 3, the polished rod holder 13 and the movable ring 4 on the fixed sleeve 9 together with the hollow shaft of the motor constitute a rotating portion.

When the motor drives the screw pump to rotate, the polished rod 3, the polished rod holder 13, the moving ring 4 connected to the fixed sleeve 9, and the hollow shaft of the motor rotate together with the motor, and the fixed sleeve 9 and the stationary ring 5 are stationary. Example 2 (see Figure 4)

The motor shaft and the mechanical seal device are the same as those in the first embodiment. The difference is that: the gasket is installed under the sealing packing, and the packing pressure cap is mounted on the sealing packing.

Example 3: (See Figure 2)

The motor shaft and the mechanical seal device are the same as those in the first embodiment, except that: a mechanical venting device housing is provided with a venting hole 12, a venting hole 12-end and a polished rod holder 13 and a motor hollow transmission shaft 17 The sealing chamber communicates with the other end communicating with the air above the mechanical seal, and the end of the air communicating with the sealing device is provided with a switchable valve 18.

When the motor drives the screw pump to rotate, the valve of the venting hole is opened, and the line pressure in the system causes the crude oil to enter the sealed cavity and drain the air in the cavity. When the crude oil rises to the valve of the venting port, the valve 18 is closed. Example 4: (See Figure 1) The motor shaft and the mechanical seal portion are the same as those in the third embodiment, except that the annular heat sink 1 is sleeved on the surface of the outer casing and fixedly connected to the polished rod holder 13 . The fin 1 is made of metal iron, and the outer ring of the fin 1 is provided with 5 rows of uniformly distributed spiral 19 protrusions. 5厘米。 The thickness of the protrusion is 0. 5cm.

Example 5: (See Figure 1)

The motor shaft and the mechanical seal device are the same as the embodiment 3, except that the annular heat sink 1 is sleeved on the surface of the outer casing and fixedly connected to the polished rod holder 13 . The heat sink 1 is made of metal aluminum, and the outer ring of the heat sink 1 is provided with 30 rows of spiral 19 protrusions. The thickness of the protrusions was 5 cm.

Example 6: (See Figure 1)

The motor shaft and the mechanical seal device are the same as the embodiment 3, except that the annular heat sink 1 is sleeved on the surface of the outer casing and fixedly connected to the polished rod holder 13 . The heat sink 1 is made of metallic copper, and the outer ring of the heat sink 1 is provided with 15 rows of uniformly distributed spiral 19 protrusions. The thickness of the protrusions was 10 cm.

Example 7: (See Figure 1)

The motor shaft and the mechanical seal device are the same as the embodiment 3 except that the annular heat sink 1 is sleeved on the surface of the outer casing and fixedly connected with the polished rod holder 13 . The heat sink 1 is made of metal aluminum, and the outer ring of the heat sink 1 is provided with two rows of spiral 19 protrusions which are uniformly distributed. The thickness of the protrusion is 2cra.

Claims

Claim

1. A motor directly drives a screw pump mechanical seal device, comprising a polished rod (3), a polished rod holder (13), a fixed sleeve (9), a moving ring (4), a stationary ring (5), a positioning bearing (8) The polished rod (3) and the polished rod holder (13) are fixed by a sealing packing (11), the polished rod (3) passes through the fixed sleeve (9), and the moving ring (4) and the fixed sleeve (9) are fixed. There is a 0-shaped sealing ring (14) between the rings (5), and a skeleton seal (7) between the stationary ring (5) on the fixing sleeve (9) and the positioning bearing (8), which is characterized in that it also includes a motor hollow transmission. The shaft (17); the polished rod (3), the polished rod holder (13), the motor hollow drive shaft (17), and the moving ring (4) connected to the fixed sleeve (9) constitute a rotating portion; the motor hollow drive shaft The side wall is provided with a leakage hole (15) and a top wire (16), and the optical rod clamp seat (10) is connected with the motor hollow transmission shaft (17) by a transmission key (6), the fixed sleeve (9) and the stationary ring ( 5) - to form a static part.

2. The motor direct drive screw pump mechanical seal according to claim 1, wherein the gasket (10) is mounted under the sealing packing, and the packing pressure cap (20) is mounted on the sealing packing.

3. The motor direct drive screw pump mechanical seal device according to claim 1, wherein a venting hole (12) is disposed on the outer casing, and one end of the venting hole (12) and the optical rod holder seat (13) and the motor hollow are provided. The mechanical seal chamber enclosed by the drive shaft (17) communicates with the other end, and the other end communicates with the air above the mechanical seal. The end of the air that communicates with the air above the seal is equipped with a switchable valve (18).

4. The motor direct drive screw pump mechanical seal device according to claim 1 or 3, characterized in that an annular heat sink (1) is sleeved on the surface of the polished rod holder (13), and is fixedly connected with the polished rod holder (13). The heat sink (1) is made of metal, and the outer ring of the heat sink is provided with a uniformly distributed spiral protrusion (19).

A motor-directed screw pump mechanical seal according to claim 3, wherein said heat sink is made of metal aluminum.

6. The motor direct drive screw pump mechanical seal of claim 3 wherein said helical projections are between 2 and 30 rows.

7. The motor direct drive screw pump mechanical seal of claim 3, wherein said helical projection has a thickness of from 0.5 cm to 10 cm.