1. A water lubricated bearing automatic pressure device used in the low speed stage of the pump, there are water lubricated bearings on the pump, characterized by that, the automatic pressure device pours into the water of the settlement pressure into the water lubricated bearing, the automatic pressure device includes the water inlet pipe (2), water tank (4) and discharging tube (5) communicated sequentially; the water inlet pipe (2) is connected with the outlet section of the pump (12); a valve (3) for controlling on-off is arranged on the water inlet pipe (2); the water outlet pipe (5) is connected to the water lubricating bearing (11); a spring top cover (7) and a spring (8) for blocking the water inlet pipe are arranged in the water tank; the spring extrudes the spring top cover (7), and the spring top cover (7) is propped against the outlet of the water inlet pipe.

2. The automatic pressurizing device for water lubricated bearing in low speed stage of pump as claimed in claim 1, characterized in that the end of the water inlet pipe (2) is provided with a first threaded pipe (1) for connection; the outer diameter of the first threaded pipe is larger than that of the water inlet pipe; a second threaded pipe (6) for connection is arranged at the end part of the water outlet pipe (5); the outer diameter of the second threaded pipe is larger than that of the water outlet pipe.

3. The automatic pressurizing device for the water-lubricated bearing in the low-speed stage of the pump according to claim 1, wherein a plurality of water outlet pipes (5) are uniformly arranged on the water tank (4) in a surrounding manner, and each water outlet pipe (5) is connected with the corresponding water-lubricated bearing.

4. A water lubricated bearing auto-pressurizing device for low-speed stage of pump according to claim 1 or 3, characterized in that a filter screen (10) is arranged at the connection of the water tank (4) and the water outlet pipe; the filter screen (10) is connected to the inner wall of the water tank.

5. A water lubricated bearing auto pressurising device for low speed stages of a pump according to claim 1 characterised in that a top post (9) is provided within the water tank (4); the spring (8) is sleeved on the top column (9), one side of the spring is arranged at the bottom of the water tank (4), and the other side of the spring is connected to the spring top cover (7); when the water pressure is greater than the threshold value and the spring compression amount reaches the designed opening, the ejection column (9) ejects the lower part of the spring top cover (7).

6. The automatic pressurizing device for water lubricated bearings for low speed stage of pump according to claim 1, characterized in that said water tank (4) comprises an upper tank, a lower tank; the upper box body is connected with the lower box body through a bolt; the upper box body is connected with a water inlet pipe, and the lower box body is connected with a water outlet pipe.

7. The automatic pressurizing device for the water-lubricated bearing in the low-speed stage of the pump as claimed in claim 1, wherein the spring top cover (7) is a truncated cone, the radius of one side of the spring top cover connected with the spring is larger than that of the other side of the spring top cover, and the other side of the spring top cover (7) is pressed against the outlet of the water inlet pipe.

8. The automatic pressurizing device for the water-lubricated bearing in the low-speed stage of the pump according to any one of claims 1 to 7, wherein the elastic coefficient of the spring is as follows:

in the formula: n is₁The rated rotation speed of the pump is unit r/min; n is₂The actual rotation speed of the pump is in r/min; h₁The pump head is the pump head at the rated rotation speed of the pump, and the unit is m; h₂Is the actual head of the pump, in m; Δ x is the preset spring compression in m; ρ is the density of water; g is the acceleration of gravity; pi is the circumference ratio; h is_f2Is the head loss of the water inlet pipe, unit m; d is the diameter of the pipeline of the water inlet pipe and the unit m.

9. The automatic pressurizing device for the water-lubricated bearing in the low-speed stage of the pump according to any one of claims 1 to 7, wherein the height of the top column is as follows:

in the formula: l is the height of the water tank in m; t is the wall thickness of the water tank in m; and x is the designed opening degree of the spring top cover in the unit of m.

Background

In a large-scale pump station pump system of hydraulic engineering, water lubrication and oil lubrication are common sliding bearing lubrication modes. The water lubricated bearing adopts water as a lubricant, generates supporting force through a wedge-shaped gap between a shaft neck and a shaft bushing, water viscosity and shaft neck rotation, forms a lubricating water film, and belongs to dynamic pressure lubrication. Compared with oil lubrication, the water lubrication bearing is mostly lubricated directly by river water, and has the advantages of simple mechanical structure and the like.

Water has a strong chemical corrosion effect on metal materials, and the shaft is made of metal materials, so that most of water-lubricated bearing friction pair materials are non-metal materials, and common water-lubricated friction pair materials comprise rubber, plastics, ceramics, graphite, high polymer materials and the like. Further, since the supporting force of the fluid lubrication film is approximately proportional to the viscosity, proportional to the speed, and inversely proportional to the square of the film thickness, the supporting force by the water lubrication is smaller than that by the oil lubrication under the same conditions because the water viscosity is lower than the oil viscosity. And under the conditions of a large pump station pump starting stage, a low-rotation-speed working condition and frequent starting and stopping under special conditions, the water-lubricated bearing is difficult to generate effective bearing force due to insufficient rotation speed of the journal, so that the journal and the bearing undergo dry friction or mixed friction, and the journal and the bearing are easily damaged. Moreover, frequent dry friction or mixed friction greatly reduces the service life of the bearing and the shaft, and if serious abrasion is not found in time, the pump station fault accident can be caused, and even the pump station can be stopped.

Disclosure of Invention

The invention aims to provide an automatic pressurizing device for a water-lubricated bearing at a low-speed stage of a pump, which can prevent the water-lubricated bearing and a shaft neck from being worn, prolong the service life of a shaft and the water-lubricated bearing and ensure the running safety of a unit.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

a water lubricated bearing automatic pressure device used in the low speed stage of the pump, there are water lubricated bearings on the pump, the automatic pressure device pours into the water of the settlement pressure into the water lubricated bearing, the automatic pressure device includes the water inlet pipe, water tank and discharging tube communicated sequentially; the water inlet pipe is connected with the outlet section of the pump; the water inlet pipe is provided with a valve for controlling on-off; the water outlet pipe is connected to the water lubrication bearing; a spring top cover and a spring for blocking the water inlet pipe are arranged in the water tank; the spring extrudes the spring top cover, and the spring top cover is propped against the outlet of the water inlet pipe.

Preferably, the end part of the water inlet pipe is provided with a first threaded pipe for connection; the outer diameter of the first threaded pipe is larger than that of the water inlet pipe; the end part of the water outlet pipe is provided with a second threaded pipe for connection; the outer diameter of the second threaded pipe is larger than that of the water outlet pipe.

Preferably, the water tank is uniformly provided with a plurality of water outlet pipes in a surrounding manner, and each water outlet pipe is connected with a corresponding water lubricating bearing.

Preferably, a filter screen is arranged at the joint of the water tank and the water outlet pipe; the filter screen is connected to the inner wall of the water tank.

Preferably, a top column is arranged in the water tank; the spring is sleeved on the top column, one side of the spring is arranged at the bottom of the water tank, and the other side of the spring is connected to the spring top cover; when the water pressure is greater than the threshold value and the spring compression amount reaches the designed opening, the ejection column ejects the lower part of the spring top cover.

Preferably, the water tank comprises an upper tank body and a lower tank body; the upper box body is connected with the lower box body through a bolt; the upper box body is connected with a water inlet pipe, and the lower box body is connected with a water outlet pipe.

Preferably, the spring top cover is a circular truncated cone, the radius of one side of the spring top cover connected with the spring is larger than that of the other side of the spring top cover, and the other side of the spring top cover is propped against the outlet of the water inlet pipe.

Preferably, the spring constant of the spring is:

in the formula: n is₁The rated rotation speed of the pump is unit r/min; n is₂The actual rotation speed of the pump is in r/min; h₁The pump head is the pump head at the rated rotation speed of the pump, and the unit is m; h₂Is the actual head of the pump, in m; Δ x is the preset spring compression in m; ρ is the density of water; g is the acceleration of gravity; pi is the circumference ratio; h is_f2Is the head loss of the water inlet pipe, unit m; d is the diameter of the pipeline of the water inlet pipe and the unit m.

Preferably, the height of the top pillar is:

in the formula: l is the height of the water tank in m; t is the wall thickness of the water tank in m; and x is the designed opening degree of the spring top cover in the unit of m.

Compared with the prior art, the invention has the following beneficial effects:

the pressurizing device comprises a water inlet pipe, a water tank and a water outlet pipe which are sequentially communicated; the water inlet pipe is connected with the outlet section of the pump; the water outlet pipe is connected to the water lubrication bearing; the water is added into the water-lubricated pump bearing, so that vibration and noise caused by friction of the water-lubricated bearing due to eccentric rotation of the shaft can be effectively relieved, and meanwhile, friction damage can be weakened to a certain degree due to the lubricating and cooling effects of the water. The invention has simple structure, small volume, low cost and simple implementation, prevents the water-lubricated bearing and the shaft neck from being worn, prolongs the service life of the shaft and the water-lubricated bearing, and ensures the operation safety of the unit.

A spring top cover and a spring for blocking a water inlet pipe are arranged in the water tank; the spring extrudes the spring top cover, the spring top cover is propped against the outlet of the water inlet pipe, when the water pressure reaches a certain strength, the spring top cover is propped open to add water to the water-lubricated bearing, the water entering the water-lubricated bearing is ensured to have a set pressure, the friction between the water-lubricated bearing and the shaft is reduced, and the operation efficiency of the pump is improved.

Drawings

FIG. 1 is a block diagram of an automatic pressurizing device for a water lubricated bearing in a low-speed stage of a pump according to an embodiment of the present invention;

fig. 2 is a structural diagram of a pump according to an embodiment of the present invention.

In the figure: the water-lubricated bearing comprises a first threaded pipe 1, a water inlet pipe 2, a valve 3, a water tank 4, a water outlet pipe 5, a second threaded pipe 6, a spring top cover 7, a spring 8, a top column 9, a filter screen 10, a pump 11 and a water-lubricated bearing 12.

Detailed Description

The invention is further described below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

It should be noted that in the description of the present invention, the terms "front", "rear", "left", "right", "upper", "lower", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of describing the present invention but do not require that the present invention must be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. As used in the description of the present invention, the terms "front," "back," "left," "right," "up," "down" and "in" refer to directions in the drawings, and the terms "inner" and "outer" refer to directions toward and away from, respectively, the geometric center of a particular component.

Taking a 20ZLB-70 as an example, the mounting blade angle of the pump is 0 degrees, and the design flow is 2099m³H, the lift is 7.0m, and the rated rotating speed is 980 r/min. The diameter of a pipeline at the outlet of the pump is 0.45m, when the pump works at a low rotating speed of 150r/min, the water lubrication bearing and the shaft rub to cause severe vibration and noise, and the friction hazard is reduced by adopting the device.

As shown in fig. 1-2, an automatic pressurizing device for a water lubricated bearing at a low-speed stage of a pump, a water lubricated bearing 12 is arranged on a pump 11, the automatic pressurizing device injects water with set pressure into the water lubricated bearing 12, and the automatic pressurizing device comprises a water inlet pipe 2, a water tank 4 and a water outlet pipe 5 which are communicated in sequence; the end part of the water inlet pipe 2 is provided with a first threaded pipe 1 for connection; the outer diameter of the first threaded pipe 1 is larger than that of the water inlet pipe 2, so that the water inlet pipe 2 is convenient to install, and the water inlet pipe 2 is connected to the outlet section of the pump 11 through the first threaded pipe 1; and a valve 3 for controlling on-off is arranged on the water inlet pipe 2, and water flow is controlled to enter and exit through opening and closing. When the water pump is started, the ball valve 3 can be opened to introduce water into the water inlet pipe 2, so that the friction between the water lubrication bearing and the shaft is reduced, and the operation efficiency of the pump is improved; when the rotating speed of the water pump reaches the rated rotating speed, the water lubricated bearing does not need water supplement, the ball valve 3 can be closed, and water supplement to the water lubricated bearing is stopped.

The end part of the water outlet pipe 5 is provided with a second threaded pipe 6 for connection; the outer diameter of the second threaded pipe 6 is larger than that of the water outlet pipe 5; the water outlet pipe is connected to a water lubrication bearing 12 through a second threaded pipe 5 and 6; the pressurizing device transmits water at the outlet section of the pump to the water-lubricated bearing so as to reduce the abrasion of the water-lubricated bearing and the shaft of the pump at the low rotating speed stage; a plurality of water outlet pipes 5 are uniformly arranged on the water tank 4 in a surrounding manner, each water outlet pipe 5 is connected with a corresponding water lubrication bearing 12, and the water replenishing efficiency of the water lubrication bearing 12 is improved through the plurality of water outlet pipes 5; a filter screen 10 is arranged at the joint of the water tank 4 and the water outlet pipe; the filter screen 10 connect in the inner wall of water tank 4 filters aquatic impurity through the filter screen, prevents that aquatic impurity from getting into the lubricated bearing of water.

The water tank 4 comprises an upper tank body and a lower tank body; the upper box body is connected with the lower box body through a bolt; the upper box body is connected with the water inlet pipe 2, the lower box body is connected with the water outlet pipe 5, and the structure is convenient for mounting the spring, the spring top cover and the top column and cleaning impurities in the water tank 5; a spring top cover 7 and a spring 8 for blocking a water inlet pipe are arranged in the water tank 4; the spring 8 extrudes the spring top cover 7, the spring top cover 7 is propped against the outlet of the water inlet pipe 2, and the water entering the water lubricating bearing is ensured to have set pressure; a top column 9 is arranged in the water tank 4; the spring 8 is sleeved on the top column 9, one side of the spring 8 is arranged at the bottom of the water tank 4, and the other side of the spring 8 is connected to the spring top cover 7; when the water pressure is greater than the threshold value, when the compression amount of the spring 8 reaches the designed opening degree, the support pillar 9 supports against the lower part of the spring top cover 7, the spring is prevented from being compressed too much, and the size of the water tank 4 is reduced.

The spring top cover 9 is a circular truncated cone, the radius of one side, connected with the spring 8, of the spring top cover 7 is larger than that of the other side of the spring top cover 7, and the other side of the spring top cover 7 is propped against the outlet of the water inlet pipe 2; the spring top cover 7 is made of rubber; the spring top cover 7 passes through the round platform structure so as to seal the outlet of the water inlet pipe 2.

According to the working principle, when the water pump is started, the ball valve 3 can be opened to introduce water into the water inlet pipe 2, and when the water pressure reaches a designed value, the spring top cover 7 is jacked open to add water to the water lubrication bearing, so that the friction between the water lubrication bearing and a shaft is reduced, and the operation efficiency of the pump is improved; when the rotating speed of the water pump reaches the rated rotating speed, the water lubricated bearing does not need water supplement, the ball valve 3 can be closed, and water supplement to the water lubricated bearing is stopped.

A design process of a water lubricated bearing pressurization device comprises the following steps: the value range of the sizes of all parts of the water-lubricated bearing device for the low-speed stage of the pump station pump is recommended as follows: the inner diameter D of the water inlet pipe 2 is 0.01m and 0.2 m; the diameter of the upper bottom of the spring top cover 7 is [0.01m,0.5m ], the diameter of the lower bottom is equal to 1.5 times of the diameter of the upper bottom, and the angle of a vertex angle is [30 degrees, 60 degrees ]; designing the opening x [0.005m,0.3m ]; the inner diameter of the water tank 4 is [0.01m,0.5m ], the height L of the water tank 4 is [0.05m,1.0m ], the wall thickness t of the water tank 4 is [0.001m,0.2m ]; the inner diameter of the water outlet pipe 5 is 0.001m and 0.2 m; the pre-compression amount of the spring 8 is Δ x [0.001m,0.5m ]; the diameter of the top pillar 9 [0.01m,0.5m ].

Under the condition of low rotating speed of the pump 11, adding water into the water-lubricated bearing, and estimating the flow and the lift of the pump by using a pump similarity law;

flow rate Q of the pump 11₂The preset formula is as follows:

=321 m³/h

in the formula, the first step is that,the rated rotation speed of the pump is unit r/min;the actual rotation speed of the pump is in r/min;is the flow rate of the pump at rated speed, in m³/s； Is the actual flow rate of the pump, in m³/s；

Flow rate of the pump 11The preset formula is as follows:

=0.16m

in the formula, the first step is that,the rated rotation speed of the pump is unit r/min;the actual rotation speed of the pump is in r/min;the pump head is the pump head at the rated rotation speed of the pump, and the unit is m;is the actual head of the pump, in m;

the diameter of the pipeline of a water inlet pipe 2 of the device is D =0.06 m; the diameter of the water tank 4 is 0.12m, the height L is 0.15m, and the wall thickness t is 0.01 m; the pre-compression amount of the spring 8 is Δ x =0.1m, and the design opening of the spring top cover 7 is x =0.06 m. The diameter of the water outlet pipe 5 is 0.01 m. The diameter of the top column 9 is 0.04 m; density ρ =1000Kg/m3 of water; the circumferential ratio pi = 3.14; local gravitational acceleration g =9.8m/s 2; h is_f2 =5%H₁And =0.008m, which is 1% -10% of the designed pump head of the pump.

According to the actual head H of the pump₂And the diameter D of the pipeline of the water inlet pipe, and the calculation formula for determining the elastic coefficient of the spring 8 is as follows:

= 44.3N/m

in the formula:for a predetermined amount of spring compression; ρ is the density of water; g is the acceleration of gravity; pi is the circumference ratio;is the head loss of the water inlet pipe; d is the diameter of the pipeline of the water inlet pipe 2, and the value range is 0.01 m-0.2 m;

when the water pressure is greater than the threshold value and the spring compression amount reaches the designed opening degree, the ejection column 9 abuts against the lower part of the spring top cover 7, and the design height L of the ejection column 9₀The calculation is as follows:

=7cm

in the formula: l is the height of the water tank 4 in m; t is the wall thickness of the water tank 4 in m; x is the design opening of the spring top cover 7 in m.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.