A wet motor design method and motor

Abstract

The present application relates to a wet motor design method and a motor, and relates to the technical field of motors. The solution gas release function F(v) is obtained to obtain the gas generation amount V D , obtain the relationship function F(p) between the volume of the pressure regulating structure and the pressure, obtain the internal volume V0 of the motor, the density ρ of the solution, the internal length L of the casing, and obtain the maximum amount of gas V that can be released when the solution volume is V0 through the function F(v) and the initial ambient temperature D0 D , the volume increase V of the solution at the highest temperature D R ; Calculate the pressure P at the pressure regulating structure in the initial state T1 , calculate the pressure P at the pressure regulating structure at the highest temperature D T2 , calculate the volume V of the gas compressed in the motor S , calculate the minimum height difference Hmin between the connection surface and the friction surface corresponding to the gas chamber after gas compression, set the safety factor k, and obtain Hmin=k*V through the cross-sectional area S of the gas chamber S / S. The present invention has the advantage of having a good lubricating effect under long-term use.

Description

Technical Field

[0001] The present application relates to the technical field of motors, and in particular to a wet motor design method and a motor. Background Art

[0002] The submersible motors for wells used in the domestic market are mainly divided into three types: water-filled, oil-filled, and dry. Dry motors are mostly used for small submersible electric pumps and are not suitable for deep well operations. The motors are prone to failure due to water seepage when running for a long time. Water-filled or oil-filled wet motors increase heat dissipation during the operation of the motor by filling water or oil (solution) inside the motor to improve the heat dissipation performance of the motor. However, after long-term use, the friction surface of the mechanical seal has a poor lubrication effect. Summary of the invention

[0003] In view of the deficiencies in the prior art, one of the purposes of the present application is to provide a wet motor design method, which has the advantage of having a good lubrication effect under long-term use.

[0004] The above-mentioned purpose of the present application is achieved through the following technical solutions:

[0005] A wet motor design method obtains the volume of gas released when the solution is heated from a specific temperature to a maximum temperature D under standard atmospheric pressure, and obtains the function F(v) of the released gas volume by fitting and the gas generation V D , obtain the relationship function F(p) between the volume of the pressure regulating structure and the pressure, obtain the space volume V0 inside the motor, the density ρ of the solution, the internal length L of the casing, and obtain the maximum gas production V that can be released when the solution volume is V0 through the function F(v) and the initial ambient temperature D0 D , the volume increase V of the solution at the highest temperature D R ; Calculate the pressure P at the pressure regulating structure in the initial state T1 , calculate the pressure P at the pressure regulating structure at the highest temperature D T2 , calculate the volume V of the gas compressed in the motor S , calculate the minimum height difference Hmin between the connection surface and the friction surface corresponding to the gas chamber after gas compression, set the safety factor k (k ≥ 1), and obtain Hmin = k*V through the cross-sectional area S of the gas chamber S / S.

[0006] In a preferred example, the present application may be further configured as follows: when obtaining the relationship function F(p) between the volume and pressure of the pressure regulating structure, the internal pressure is measured by quantitatively injecting a solution.

[0007] In a preferred example, the present application can be further configured as follows: Assume standard atmospheric pressure P0, P T2The calculation method is, P S = P0V D / V S , P T2 =ρ 液 gh +P S , where g is the acceleration due to gravity.

[0008] The present application also discloses a motor designed by using the above-mentioned wet motor design method.

[0009] This application has the following advantages:

[0010] By calculating the minimum height difference Hmin, the friction surface of the mechanical seal can be located below the liquid level during the use cycle, so that the mechanical seal can always be lubricated. At the same time, by setting the minimum height difference Hmin, the installation position of the mechanical seal can be as high as possible, that is, the position of the mechanical seal is as far out as possible, so as to facilitate disassembly, assembly and replacement. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the cross-sectional structure of the motor of this application.

[0012] Figure numerals: 1. Mechanical seal; 11. Friction surface; 2. Air chamber; 3. Connection surface; 4. Pressure regulating structure. DETAILED DESCRIPTION

[0013] The present application is further described in detail below in conjunction with the accompanying drawings.

[0014] Reference Figure 1 , which is a wet motor design method disclosed in the present application, obtains the volume of gas released by the solution when it is heated from a specific temperature (such as 0°C) under standard atmospheric pressure P0 and continues at the highest temperature D (the data can be obtained by experiment or through reference materials such as textbooks), and obtains the gas generation volume V by fitting the function F(v) of the released gas volume D (The function can be obtained through tools such as MATLAB); Similarly, when the external environment is the standard atmospheric pressure P0, the relationship function F(p) between the volume and pressure of the pressure regulating structure is obtained (the corresponding data can be obtained through experiments or through reference materials such as textbooks). Since it is inconvenient to calculate the corresponding volume during the expansion process of the pressure regulating structure 4, in order to ensure that the pressure of the external environment of the pressure regulating structure 4 remains unchanged during the test, it is not appropriate to use the drainage method or other methods to measure the volume change. The internal pressure can be measured by quantitatively filling the solution; and the expansion coefficient or function of the filled solution is obtained through experiments, or a solution with a known expansion coefficient or function is used to obtain the increase in the volume of the solution in each temperature range;

[0015] The pressure regulating structure 4 can be attached Figure 1The shape shown may also be a capsule shape or other deformable shapes, and the pressure regulating structure 4 is made of a deformable material, such as rubber or silicone.

[0016] Obtain the volume V0 of the space inside the motor (the volume formed by the housing and the voltage regulating structure 4 minus the volume of other contents, such as the volume of the stator, rotor shaft and other structures), and the volume when the internal solution is filled is V0;

[0017] Density of the solution ρ, unit Kg / m 3 , the internal length of the casing L, in m;

[0018] From the function F(v) and the initial ambient temperature D0, we can get: the maximum gas production V that can be released by a solution volume of V0 under standard atmospheric pressure D ;

[0019] The volume increase V of the solution at the highest temperature D R ;

[0020] Calculate the pressure P at the pressure regulating structure 4 in the initial state T1 ;

[0021] According to the liquid pressure formula P = ρgh, since ρ, g (gravitational acceleration), and h (i.e., the internal length of the casing L) are all known values, P is obtained. T1 ;

[0022] Calculate the pressure P at the pressure regulating structure 4 at the highest temperature D T2 ;

[0023] Since the maximum gas generation V under standard atmospheric pressure P0 D , then according to the gas pressure formula PV=nRT, P0*V D =P S * V S , then P S = P0V D / V S ; Here in P S The volume of the gas redissolved in the solution is considered as a safety margin, that is, the corresponding pressure of the actual gas after compression will be slightly less than P S ;

[0024] At this time P T2 =ρ 液 gh+P 气 , that is, P T2 =P T1 +P S (The external environment here is the standard atmospheric pressure P0, which is the same as the experimental environment, so P0 is not introduced in the formula here);

[0025] Calculate the volume V of the compressed gas in the motorS :

[0026] The relationship between the volume and pressure of the pressure regulating structure 4 is used to obtain P T1 , P T2 The corresponding volume and calculate the volume increase V of the pressure regulating structure 4 T ; Then the volume V of the gas after compression S =V T -V R ;

[0027] Calculate the minimum height difference Hmin between the connecting surface 3 and the friction surface 11 in the gas chamber 2 after the gas is compressed:

[0028] Set the safety factor k (k ≥ 1), and obtain Hmin = k*V through the approximate cross-sectional area S of the air chamber 2. S / S.

[0029] The present application also discloses a motor obtained by adopting the above-mentioned design method.

[0030] The implementation principle of this embodiment is: by calculating the minimum height difference Hmin, the friction surface 11 can be located below the liquid level during the service life of the mechanical seal 1, thereby ensuring that the mechanical seal 1 is always lubricated to avoid dry grinding. After replacing the mechanical seal 1, the liquid in the motor is replenished or replaced, and the air generated by the liquid can also be discharged. By setting the minimum height difference Hmin, the position of the mechanical seal 1 can also be as high as possible, that is, the position of the mechanical seal 1 is as far out as possible, so as to facilitate disassembly and replacement.

[0031] The embodiments of this specific implementation method are all preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Therefore, all equivalent changes made based on the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A wet motor design method, characterized in that: Obtain the volume of gas released when the solution is heated from a specific temperature to the highest temperature D under standard atmospheric pressure, and obtain the gas generation volume V by fitting the function F(v) of the released gas volume D , obtain the relationship function F(p) between the volume of the pressure regulating structure and the pressure, obtain the space volume V0 inside the motor, the density ρ of the solution, the internal length L of the casing, and obtain the maximum gas production V that can be released when the solution volume is V0 through the function F(v) and the initial ambient temperature D0 D , the volume increase V of the solution at the highest temperature D R ; Calculate the pressure P at the pressure regulating structure in the initial state T1 , calculate the pressure P at the pressure regulating structure at the highest temperature D T2 , calculate the volume V of the gas compressed in the motor S , calculate the minimum height difference Hmin between the connection surface of the air chamber and the friction surface of the mechanical seal after gas compression, set the safety factor k (k ≥ 1), and obtain Hmin = k*V through the cross-sectional area S of the air chamber S / S.

2. A wet motor design method according to claim 1, characterized in that: When obtaining the relationship function F(p) between the volume and pressure of the pressure regulating structure, the internal pressure is measured by quantitatively injecting the solution.

3. A wet motor design method according to claim 1, characterized in that: Assume standard atmospheric pressure P0, P T2 The calculation method is, P S = P0V D / V S , P T2 =ρ 液 gh +P S , where g is the acceleration due to gravity, h is the internal length of the casing L, and ρ 液 is the density ρ of the solution.

4. A motor, characterized in that: The wet motor is designed by using a wet motor design method as described in any one of claims 1 to 3.

Images