Eccentricity adjustment method for liquid ring pump

Abstract

The present application belongs to the technical field of liquid ring pump, especially to a liquid ring pump eccentricity adjusting method, comprising the following steps: step 1, setting the fixing mechanism at both ends of the pump body of the liquid ring pump into a flange plate form, eccentrically setting the inner cavity of the pump body of the liquid ring pump and the fixing mechanism at both ends thereof, the eccentricity value being a, then the maximum total eccentricity E1 of the liquid ring pump = e + a; step 2, calculating the optimal rotation angle through a formula, calculating the corresponding number of bolt holes C = α × Z / 360; step 3, rotating the liquid ring pump by the corresponding number of bolt holes C, thereby obtaining the optimal eccentricity value E2 = e + b, wherein b = a * cos (C * β). The present application adjusts the optimal installation angle, thereby realizing the adjustment of the optimal eccentricity value, and thereby realizing that the liquid ring pump can achieve the optimal working efficiency under different working speeds; the limit working point suction capacity of the liquid ring pump is greatly improved, and the working efficiency is also greatly improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of liquid ring pumps, in particular to a liquid ring pump eccentricity adjusting method. BACKGROUND

[0002] The liquid ring pump is a gas pumping device taking working liquid as energy transmission medium, and its working principle is that an impeller is eccentrically installed in a nearly circular pump body, Figure 1 is a lateral section view of the prior art liquid ring pump, Figure 2 is a front section view of the prior art liquid ring pump (i.e. a structure schematic view of the pump body inner cavity), Figure 1 10 is a rotor center line, and 11 is a pump body inner cavity center line, Figure 2 12 is a rotor center point, and 13 is a pump body inner cavity center point, when the impeller rotates, due to the centrifugal force, the liquid injected into the pump body forms a rotating liquid ring, an inner surface of the liquid ring and the impeller hub form a crescent-shaped space, and the cavities enclosed between two adjacent blades gradually increase, and the gas is sucked from the outside; when the impeller continues to rotate, the corresponding cavities change from large to small, so that the originally sucked gas is compressed, and when the pressure reaches or is slightly greater than the atmospheric pressure, the gas is discharged.

[0003] The design of the liquid ring pump is that the impeller and the pump body inner cavity are eccentrically arranged, and in general, the eccentricity value e is a fixed value, i.e. the eccentricity value e of the liquid ring pump product cannot change. In the working process of the liquid ring pump, gas suction and discharge are realized, which is actually a process of converting the kinetic energy of the liquid in the pump into the potential energy of the gas. However, the liquid ring pump can usually work at different speeds, when the speed increases, the kinetic energy of the liquid ring increases, the resistance loss increases, and the efficiency of the liquid ring pump also decreases; when the speed decreases, the kinetic energy of the liquid ring decreases, and the liquid ring may be unstable or even unable to form during the working process, thereby causing unstable gas suction and discharge or even normal working problems. Therefore, when the eccentricity value e is fixed, the high-efficiency working point of the liquid ring pump can only be fixed at a rated speed, and the overall working efficiency is relatively low. SUMMARY

[0004] In order to overcome the defects of the prior art, the present application provides a liquid ring pump eccentricity adjusting method, which realizes the adjustment of the optimal eccentricity value, so that the liquid ring pump can achieve the best working efficiency at different working speeds. The technical problem to be solved by the present application is realized through the following technical scheme:

[0005] A liquid ring pump eccentricity adjusting method, comprising the following steps:

[0006] Step 1, the fixing mechanism at both ends of the pump body of the liquid ring pump is arranged in the form of a flange plate, Z holes are drilled on the flange plate, and the pump body inner cavity of the liquid ring pump is eccentrically arranged with the fixing mechanism at both ends thereof, the eccentricity value is a, and the maximum total eccentricity E1 of the liquid ring pump is e+a.

[0007] Step 2, the best rotation angle is alpha, the rotation angle is beta, the number of rotating bolt holes is C, the flange is the center, and the rotation angle beta = 360 / Z for each rotation hole, the number of rotating bolt holes corresponding to the best rotation angle C = a*Z / 360 (rounding to the nearest integer), and the best rotation angle is calculated by alpha formula:

[0008]

[0009] n is the rotating speed, unit: rpm;

[0010] Kappa is the structure coefficient;

[0011] D is the impeller diameter, unit: m;

[0012] Delta is the length-diameter ratio of the impeller;

[0013] P is the maximum working pressure difference, unit: Pa;

[0014] Step 3, according to the actual required rotating speed n, the flange is the center, the number of rotating bolt holes C of the liquid ring pump is obtained, and the best eccentricity value E2 = e + b is obtained, wherein b = a*cos(C*beta).

[0015] Further, the value of Z is 10-50.

[0016] Further, the value of kappa is 3-6.

[0017] The present application adjusts the best installation angle, thereby adjusting the best eccentricity value, so that the liquid ring pump can achieve the best working efficiency under different working speeds; the limit working point of the liquid ring pump is greatly improved, and the working efficiency is also greatly improved. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a lateral section view of the existing liquid ring pump;

[0019] Figure 2 It is a front section view of the existing liquid ring pump;

[0020] Figure 3 It is a structure diagram of the pump body inner cavity of the liquid ring pump of the present application;

[0021] Figure 4 It is a structure diagram of the pump body inner cavity of the liquid ring pump after adjusting the angle of the present application. DETAILED DESCRIPTION

[0022] Figure 3 It is a structure diagram of the pump body inner cavity of the liquid ring pump of the present application, Figure 4Structure diagram of the pump body inner cavity after adjusting the angle of the liquid ring pump of the application, Figure 3 and Figure 4 In the figure, 12 is the rotor center point, 13 is the pump body inner cavity center point of the application, 14 is the flange center point, and 15 is the initial vertex of the flange, Figure 4 In the figure, 16 is the axis of the initial vertex of the flange, and 17 is the axis in the vertical direction after adjusting the angle, a liquid ring pump eccentric adjustment method comprises the following steps:

[0023] Step 1: The fixing mechanism at both ends of the pump body of the liquid ring pump is set in the form of a flange 1, Z holes 2 are drilled on the flange 1, and the pump body inner cavity 3 of the liquid ring pump is eccentrically arranged with the fixing mechanism at both ends, with an eccentric value a, that is, the pump body inner cavity center point 13 and the flange center point 14 have an eccentric value a in the vertical direction, and the rotor center point 12 and the flange center point 14 have an eccentric value e in the vertical direction, as shown in the figure, then the maximum total eccentricity E1 of the liquid ring pump in the vertical direction is e+a. Figure 3

[0024] Step 2: The optimal rotation angle is α, the rotation angle is β, the number of rotating bolt holes is C, and the flange is taken as the center, then the rotation angle β=360 / Z, the number of rotating bolt holes C corresponding to the optimal rotation angle is α×Z / 360 (rounded to an integer), and the optimal rotation angle is calculated by the following formula:

[0025]

[0026] In the formula, ρ is the working liquid density, with the unit of Kg / m 3 ;

[0027] n is the rotation speed, with the unit of rpm;

[0028] κ is the structure coefficient;

[0029] d is the impeller diameter, with the unit of m;

[0030] δ is the length-diameter ratio of the impeller, that is, the ratio of the length and the diameter;

[0031] p is the maximum working pressure difference, with the unit of Pa.

[0032] Step 3: The number of rotating bolt holes corresponding to the optimal rotation angle is calculated according to the actual required rotation speed n, the flange 1 is taken as the center, and the liquid ring pump is rotated by the corresponding number of bolt holes C, at this time, the axis 16 of the initial vertex of the flange and the axis 17 in the vertical direction after adjusting the angle form an angle α1, as shown in the figure, α1=C*β, and the eccentric value on the vertical line becomes E2=e+b, where b=a*cos(C*β). Figure 4 ​​

[0033] Wherein, the value range of Z in step 1 is 10-50, the value range of K in step 2 is 3-6, the total eccentricity E2 of the pump body with different installation angles is different, the total eccentricity E2 of the pump body is composed of two parts, e is unchanged with the change of the pump body angle, and the value of a in the vertical direction becomes b=a*cos(C*beta), therefore, E2=e+b.

[0034] The following is an actual example:

[0035] Step 1, the fixed mechanism at both ends of the pump body of the liquid ring pump is set to the form of flange plate 1, 24 holes 2 are drilled on the flange plate 1, the impeller diameter d of the pump is 0.72m, the length to diameter ratio δ is 1.4, the inner cavity 3 of the pump body is designed to have an eccentricity a of 8mm with the flange plate 1, the center point of the rotor 4 has a fixed eccentricity e of 50mm with the center point of the flange plate 1, and the maximum total eccentricity E1 of the liquid ring pump is e+a=58mm.

[0036] Step 2, the optimal rotation angle is alpha, the rotation angle is beta, the number of bolt holes rotated is C, the flange plate 1 is taken as the center, the rotation angle beta is 360 / 24=15 when rotating one hole, the working maximum pressure difference p is 100000Pa, the working liquid is water, the density p is 1000Kg / m 3 , the structure coefficient K is 4, and the rotation speed n is 372rpm; the optimal rotation angle is

[0037]

[0038] When rotating clockwise, the number of bolt holes C corresponding to the optimal rotation angle is C=53.7 / 15≈4.

[0039] Step 3, according to the actual required rotation speed 372rpm, the liquid ring pump of the application is rotated by the number of bolt holes C corresponding to the flange plate, at this time, the corresponding eccentricity E2 is e+b=e+a*cos(C*beta)=54mm, the comprehensive performance of the liquid ring pump reaches the best, and therefore it is the optimal eccentricity.

[0040] The formula of the application is derived from the results and experience summary of a large number of performance tests of liquid ring pump products of various specifications at various rotation speeds with different installation angles, therefore, the eccentricity corresponding to the calculated rotation angle can make the comprehensive performance of the liquid ring pump reach the best.

[0041] The present application adjusts the optimal installation angle, thereby adjusting the optimal eccentricity, so that the liquid ring pump can reach the optimal working efficiency at different working speeds. The liquid ring pump of the present application is generally fixed at one speed during use. If the speed is changed or the maximum pressure difference changes, the angle is recalculated and adjusted according to step 2.

[0042] A liquid ring pump with an impeller diameter d=0.72m and a length-to-diameter ratio δ=1.4 was tested, wherein A is a liquid ring pump without adjustable eccentricity, and B is the liquid ring pump of the present application with adjusted installation angle. When the eccentricity cannot be changed, only one speed can be taken as the high-efficiency point design. Here, the highest speed is taken as the high-efficiency point design. See Table 1.

[0043] Table 1

[0044]

[0045] It can be seen that the liquid ring pump of the present application can reach the optimal working efficiency at different working speeds. Compared with the existing liquid ring pump without adjustable eccentricity, the limit working point suction capacity of the liquid ring pump of the present application is greatly improved, and the working efficiency is also greatly improved.

[0046] In summary, the present application adjusts the optimal installation angle, thereby adjusting the optimal eccentricity, so that the liquid ring pump can reach the optimal working efficiency at different working speeds. The limit working point suction capacity of the liquid ring pump of the present application is greatly improved, and the working efficiency is also greatly improved.

Claims

1. A method for adjusting the eccentricity of a liquid ring pump, characterized in that, Includes the following steps: Step 1: Set the fixing mechanism at both ends of the liquid ring pump body to the form of a flange, drill Z holes on the flange, and set the inner cavity of the liquid ring pump body to be eccentric with the fixing mechanism at both ends of itself. The eccentricity value is a. Then the maximum total eccentricity of the liquid ring pump is E1 = e + a. Step 2: Let the optimal rotation angle be α, the rotation angle be β, and the number of bolt holes rotated be C. With the flange as the center, for each hole rotated, the rotation angle β = 360 / Z. Therefore, the number of bolt holes rotated corresponding to the optimal rotation angle is C = α × Z / 360 (rounded to the nearest integer). The optimal rotation angle is calculated using the following formula: Where ρ is the working fluid density, in kg / m³. 3 ; n represents the rotational speed, in rpm; κ is the structural coefficient; d is the impeller diameter, in meters (m). δ is the length-to-diameter ratio of the impeller; p is the maximum operating differential pressure, in Pa. Step 3: Based on the actual required rotational speed n, with the flange as the center, rotate the liquid ring pump to the corresponding number of bolt holes C, thereby obtaining the optimal eccentricity value E2=e+b, where b=a*cos(C*β).

2. The eccentricity adjustment method for a liquid ring pump according to claim 1, characterized in that, The value of Z is 10-50.

3. The eccentricity adjustment method for a liquid ring pump according to claim 1, characterized in that, The value of κ is 3-6.

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