阅读说明：本技术 一种船用海水提升泵轴向力的平衡方法及平衡结构 (Marine seawater lifting pump axial force balancing method and balancing structure ) 是由 梁杰 常瑛 徐俊 陈乃娟 于 2019-10-22 设计创作，主要内容包括：本发明公开的一种船用海水提升泵轴向力的平衡方法,其特征在于,减小轴向力的程度取决于密封环所在的直径、密封环间隙、平衡孔的数量和孔径大小之间的相互配合程度。本发明还公开了一种船用海水提升泵的轴向力平衡结构。本发明通过合理设计密封环所在的直径、密封环间隙、平衡孔的数量和孔径大小三个技术参数来有效的平衡轴向力。(The invention discloses a balance method for axial force of a marine seawater lift pump, which is characterized in that the degree of reducing the axial force depends on the mutual matching degree among the diameter of a sealing ring, the gap of the sealing ring, the number of balance holes and the size of the hole diameter. The invention also discloses an axial force balance structure of the marine seawater lift pump. The axial force balance device can effectively balance the axial force by reasonably designing the three technical parameters of the diameter of the sealing ring, the gap of the sealing ring, the number of the balance holes and the size of the hole diameter.)

1. A method for balancing the axial force of seawater lift pump for ship features that the axial force is decreased by the diameter of sealing ring, the gap between sealing rings, the number of balancing holes and the size of balancing holes.

2. The method for balancing the axial force of a marine seawater lift pump according to claim 1, wherein the sealing rings are two front and rear sealing rings respectively mounted on the front and rear cover plates of the impeller.

3. The method for balancing axial forces of marine seawater lift pumps of claim 2, wherein the front sealing ring has a diameter different from a diameter of the rear sealing ring.

4. The method for balancing the axial force of a marine seawater lift pump according to claim 3, wherein the diameter of the rear sealing ring is larger than the diameter of the front sealing ring.

5. The method for balancing the axial force of a marine seawater lift pump according to claim 2, wherein a seal ring gap is formed between the rear seal ring and the impeller rear cover plate, and the seal ring gap enables the cavity B of the rear pump cavity to communicate with an impeller suction port or a suction chamber of the pump, so as to achieve the purpose of balancing the axial force.

6. The method for balancing the axial force of a marine seawater lift pump according to claim 5, wherein the balancing hole is formed in the back cover plate adjacent to the impeller hub to communicate the chamber A of the impeller suction inlet with the chamber B of the back pump chamber.

7. The method for balancing the axial force of a marine seawater lift pump according to claim 6, wherein the total area of the radial cross section of the balance hole is not less than 5 to 8 times the area of the cross section of the sealing ring.

8. The method for balancing axial forces of marine seawater lift pumps of claim 7, wherein the diameter of the balancing hole is inversely proportional to the balanced axial force.

9. An axial force balance structure of a marine seawater lift pump comprises two sealing rings respectively arranged on a front cover plate and a rear cover plate of an impeller and a plurality of balance holes arranged on the rear cover plate close to a hub of the impeller, wherein a cavity B of a rear pump cavity is communicated with an impeller suction inlet or a suction chamber of the pump through the gap of the sealing rings, and the balance holes are used for communicating a cavity A of the impeller suction inlet with a cavity B of the rear pump cavity; and a sealing ring gap is formed between the sealing ring and the rear cover plate of the impeller.

10. The axial force balance structure of marine seawater lift pump of claim 9, wherein the total area of the radial cross section of the balance aperture should not be less than 5 to 8 times the area of the cross section of the clearance of the sealing ring.

Technical Field

The invention relates to the technical field of marine seawater lift pumps, in particular to a method for balancing axial force of a marine seawater lift pump and an impeller balancing structure.

Background

In the application of the marine pump, the marine seawater lift pump which is easy to operate and convenient to use is the preferred requirement of customers due to the limitation of sites.

Marine lift pumps are centrifugal pumps in which if one does not try to eliminate or balance the axial force on the impeller (transmitted to the shaft), the axial force will pull the rotor axially into play, contacting stationary parts, causing damage to the pump parts. At present, two methods are used for balancing axial force in a marine seawater lifting pump: one is to design the balance hole, the other is the balance pipe, the axial force can be well balanced, and meanwhile, the characteristics of easy maintenance and improvement of the reliability and safety of the equipment operation can be met. However, the balance method has large leakage amount and little effect of balancing the axial force.

Disclosure of Invention

One of the technical problems to be solved by the invention is to provide a method for balancing the axial force of a marine seawater lift pump, aiming at the defects of the existing method for balancing the axial force in the marine seawater lift pump.

The second technical problem to be solved by the present invention is to provide an axial force balance structure of marine seawater lift pump.

The method for balancing the axial force of the marine seawater lift pump is characterized in that the degree of reducing the axial force depends on the mutual matching degree among the diameter of the sealing ring, the gap of the sealing ring, the number of the balancing holes and the size of the hole diameter.

In a preferred embodiment of the present invention, the sealing ring is a front sealing ring and a rear sealing ring which are respectively arranged on a front cover plate and a rear cover plate of the impeller.

In a preferred embodiment of the invention, the front sealing ring is present at a different diameter than the rear sealing ring.

In a preferred embodiment of the invention, the rear sealing ring is of a larger diameter than the front sealing ring.

In a preferred embodiment of the present invention, a sealing ring gap is formed between the rear sealing ring and the impeller rear cover plate, and the sealing ring gap enables the cavity B of the rear pump cavity to be communicated with an impeller suction port or a pump suction chamber, so as to achieve the purpose of balancing the axial force.

In a preferred embodiment of the present invention, the balancing hole is provided on the back cover plate near the impeller hub to communicate the chamber a of the impeller suction inlet and the chamber B of the back pump chamber.

In a preferred embodiment of the invention, the total area of the radial cross section of the balance hole is not less than 5-8 times of the cross section area of the sealing ring.

In a preferred embodiment of the invention, the diameter of the balancing hole is inversely proportional to the axial force to be balanced out.

The axial force balance structure of the marine seawater lift pump as the second aspect of the invention comprises two sealing rings respectively arranged on the front cover plate and the rear cover plate of an impeller and a plurality of balance holes arranged on the rear cover plate close to the hub of the impeller, wherein the cavity B of a rear pump cavity is communicated with an impeller suction inlet or a suction chamber of the pump through the gap of the sealing rings, and the balance holes are used for communicating the cavity A of the impeller suction inlet with the cavity B of the rear pump cavity; and a sealing ring gap is formed between the sealing ring and the rear cover plate of the impeller.

Due to the adoption of the technical scheme, the axial force is effectively balanced by reasonably designing the three technical parameters of the diameter of the sealing ring, the gap of the sealing ring, the number of the balancing holes and the size of the hole diameter.

Drawings

Fig. 1 is a schematic view of an axial force balance structure of the marine seawater lift pump of the present invention.

Detailed Description

The invention is further described below in conjunction with the appended drawings and detailed description. The following embodiments are implemented on the premise of the technical solution of the present invention, and detailed embodiments and specific design procedures are given, but the scope of the present invention is not limited to the following embodiments.

For the marine seawater lift pump with small axial force, the requirement of convenient daily maintenance is met, the system is simple, the thrust bearing is not designed to bear the axial force, and the sealing ring, the balance hole and the sealing gap are designed to be matched with each other to reasonably balance the axial force.

As shown in fig. 1, a seal ring 11 is additionally provided to a rear cover plate 12a of an impeller 12, and a seal ring 11a is also provided to a front cover plate 12B of the impeller 12, and a diameter C of the seal ring 11 is larger than a diameter D of the seal ring 11a, and a seal ring gap E is provided between the seal ring 11 and the rear cover plate 12a of the impeller, and the seal ring gap E allows a cavity B of a rear pump cavity to communicate with an impeller suction port or a pump suction chamber. In addition, a balance hole 13 for communicating the chamber a of the impeller suction port and the chamber B of the rear pump chamber is opened in the rear cover plate 12a of the impeller 12. Due to the loss of resistance to the liquid flowing through the seal ring gap E, the pressure of the liquid at the lower portion of the seal ring 11 is lowered, thereby reducing the axial force acting on the back cover plate 12 a.

The sealing ring clearance E between the sealing ring 11 and the back cover plate 12a of the impeller is generally in the range of 0.2-0.3 mm, and the relationship between the aperture size and the number of the balance holes 13 and the sealing ring clearance E is that the total area of the radial sections of the balance holes 13 is not less than 5-8 times of the area of the sections of the sealing ring clearance E.

The aperture of the balance hole 13 is inversely proportional to the balanced axial force, generally about 97% of the balanced axial force is theoretically needed, and the rest of the axial force needs to be balanced by a bearing of the motor.