JP2019167829A - Special rubber supporting bearing for vertical long-sized pump and special rubber damper device for vertical long-sized pump - Google Patents

Abstract

To provide a special rubber supporting bearing for a vertical long-sized pump capable of avoiding a dry friction whirl.SOLUTION: A dumper inner cylinder 2 is outwardly fitted to a bearing inner cylinder 1 accepting a rotating shaft, a damper member 4 is interposed between the damper inner cylinder 2 and a damper outer cylinder 3, a bearing case 5 supported by a fixed structure portion of a vertical pump is installed outside the damper outer cylinder 3 and rubber showing a tangent loss more than a value attained by a following process is applied to the damper member 4. A destabilization coefficient Kxy derived from a friction coefficient μ that becomes a cause of a dry friction whirl is converted. This invention is characterized in that if this value is larger than the maximum coefficient of friction (μc>μreal) that can be attained at the bearing, a friction whirl is not generated, and a tangent loss tanδ(=Cω/K) showing μc>μreal is calculated so as to adopt a rubber for realizing it.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a special rubber support bearing for a vertical long pump and a special rubber vibration isolator for a vertical long pump.

  Conventionally, various vertical pumps used for pumping water have been proposed (Patent Document 1, Patent Document 2). This vertical pump generally has a structure in which a transmission shaft of a driving machine and a rotary shaft of the pump are connected to an external shaft joint, and the rotary shaft is rotatably supported by bearings at least at two upper and lower positions.

  By the way, a prior standby pump is known as this type of vertical pump (Patent Document 3), and the prior standby pump can wait for the pump in a full-speed operation state from a state where there is no water in the suction water tank of the pump. When the water level reaches the height near the tip of the rotating impeller, the pumping can be started. The normal vertical pump generates large vibrations and sounds due to the vortices that are generated, but the standby pump suppresses the generation of vortices by taking in air from the atmosphere and smoothly transitions from air operation to pumping operation. To be able to do that.

JP 11-37082 A JP 2000-345990 A JP 2000-266042 A

  However, the prior standby pump described in Patent Document 3 generates a dry friction whirl depending on the friction coefficient of a bearing (hereinafter referred to as “submersible bearing”) that should be located underwater during the dry operation (in-air operation) of the pump. This may cause damage such as burnout of the bearing and the bearing sleeve.

  This invention makes it a subject to provide the special rubber | gum support bearing of a vertical elongate pump which enabled it to avoid a dry friction whirl in view of this problem.

Therefore, in the special rubber support bearing of the vertical long pump according to the present invention, a damper inner cylinder is fitted on the bearing inner cylinder that receives the rotation shaft, and a damper member is provided between the damper inner cylinder and the damper outer cylinder. A bearing box which is interposed and supported by the fixed structure portion of the vertical long pump is provided outside the damper outer cylinder. The characteristics of the damper member are as follows: static spring: K, damping: Cω = tanδ * K, tangent loss: tanδ = Cω / K. The damper member is made of rubber whose tangent loss is not less than the value obtained by the following method. It was determined limit Kxy by the rotor dynamics analysis using the dry friction destabilizing factor derived from the causative friction coefficient μ ho Waal Kxy = -μK = -μ * (K 2 + (Cω) 2) 1/2 Later, the limit friction coefficient μc = limit Kxy / (K ² + (Cω) ² ) ^1/2 is converted. If this value is larger than the maximum friction coefficient [mu] real that the bearing can take ([mu] c> [mu] real), no friction whirl is generated, and if [mu] <[mu] real, a friction whirl is generated. A tan δ (= Cω / K) such that μc> μreal is obtained, and a rubber that realizes this is employed.

Further, in the special long rubber support bearing of the vertical long pump according to the present invention, a damper inner cylinder is externally fitted to a bearing inner cylinder that receives a rotating shaft, and a damper member is provided between the damper inner cylinder and the damper outer cylinder. A bearing box that is interposed and supported by the fixed structure portion of the rotating machine is provided outside the damper outer cylinder. The characteristics of the damper member are as follows: static spring: K, damping: Cω = tanδ * K, tangent loss: tanδ = Cω / K. The damper member is made of rubber whose tangent loss is not less than the value obtained by the following method. It was determined limit Kxy by the rotor dynamics analysis using the dry friction destabilizing factor derived from the causative friction coefficient μ ho Waal Kxy = -μK = -μ * (K 2 + (Cω) 2) 1/2 Later, the limit friction coefficient μc = limit Kxy / (K ² + (Cω) ² ) ^1/2 is converted. If this value is larger than the maximum friction coefficient that the bearing can take (μc> μreal), no friction whirl is generated, and if μc <μreal, a friction whirl is generated. A tan δ (= Cω / K) such that μc> μreal is obtained, and a rubber that realizes this is employed. The rubber is characterized in that the resonance magnification at the primary critical speed is such that the vibration becomes a small amplitude vibration.

  Furthermore, the special rubber support bearing of the vertical long pump according to the present invention preferably further includes a device for cooling the damper inner cylinder and the damper member.

  Further, in the special rubber support bearing of the vertical long pump according to the present invention, it is preferable that the tangent loss of the damper member is at least 0.3.

Further, according to the present invention, there is provided a special rubber vibration isolator for a vertical long pump provided on a rotary shaft directly below an external bearing that connects a rotary shaft of a vertical pump and a transmission shaft of a drive machine, A damper inner cylinder is fitted on the bearing inner cylinder that receives the shaft, and a damper member is interposed between the damper inner cylinder and the damper outer cylinder, and is supported by the fixed structure portion of the vertical pump outside the damper outer cylinder. A bearing housing is provided. The characteristics of the damper member are as follows: static spring: K, damping: Cω = tanδ * K, tangent loss: tanδ = Cω / K. The damper member is made of rubber whose tangent loss is not less than the value obtained by the following method. It was determined limit Kxy by the rotor dynamics analysis using the dry friction destabilizing factor derived from the causative friction coefficient μ ho Waal Kxy = -μK = -μ * (K 2 + (Cω) 2) 1/2 Later, the limit friction coefficient μc = limit Kxy / (K ² + (Cω) ² ) ^1/2 is converted. If this value is larger than the maximum friction coefficient that the bearing can take (μc> μreal), no friction whirl is generated, and if μc <μreal, a friction whirl is generated. A tangent loss tan δ (= Cω / K) such that μc> μreal is obtained, and a rubber that realizes this is employed. The rubber can provide a special rubber vibration isolator for a vertical long pump.

It is a figure which shows preferable embodiment of the special rubber support bearing of the vertical elongate pump which concerns on this invention. It is a figure which shows the relationship between the tangent loss and temperature of special rubber and normal rubber. It is a figure which shows typically the dynamic characteristic of the bearing with respect to a minute vibration. It is a figure which shows typically the dry friction whirl stability analysis method. It is a figure which shows the structure of a model pump, and the shaft system which simplified it. It is a figure which shows the relationship between the natural frequency fi and damping ratio (zeta) i in tangent loss 0.1 and 0.6. It is a figure which shows the relationship of the vibration response magnification with respect to rotation speed. It is a figure which shows preferable embodiment of the special rubber support bearing of a vertical elongate pump provided with the cooling device of rubber | gum. It is a figure which shows preferable embodiment of the special rubber support bearing of the vertical long pump provided with the other cooling device of rubber | gum. It is a figure which shows preferable embodiment of the special rubber support bearing of the vertical long pump provided with the further cooling device of rubber | gum. It is a figure which shows preferable embodiment of the special rubber vibration isolator of the vertical long pump which concerns on this invention. It is a figure which shows 2nd Embodiment of the special rubber vibration isolator of the vertical long pump which concerns on this invention. It is a figure which shows the structural example of the external bearing in a vertical long pump. It is a figure which shows 3rd Embodiment of the special rubber vibration isolator of the vertical long pump which concerns on this invention. It is a figure which shows typically the example of a countermeasure against vibration by this invention. It is a figure which shows the relationship of the vibration amplitude with respect to the rotation speed when the vibration countermeasure is performed in the present invention and when it is not performed. It is a figure which shows one example of the method of a rotor dynamics analysis. It is a figure which shows the relationship between the limit (micro | micron | mu) of primary mode, and tangent loss tan-delta (= Comega / Kxx).

  The structure of this type of bearing will be described. As shown in FIGS. 1A and 1B, a damper inner cylinder 2 is fitted on a bearing inner cylinder 1 that receives a rotating shaft. A damper member 4 is interposed between the outer cylinder 3 and a bearing box 5 supported by a fixed structure portion of the rotary machine is provided outside the damper outer cylinder 3.

  Conventionally, there has been no simple method for theoretically predicting the tangent loss tanδ (= Cω / K) in which the underwater bearing can avoid the dry friction whirl in the preceding standby pump. The analysis method can predict Cω / K that avoids dry friction whirl. Further, by adopting a special rubber having a high damping characteristic that realizes Cω / K that can avoid the dry friction whirl, the dry friction whirl can be avoided.

The new stability analysis can be performed in the following relationship. In general, the dynamic characteristics of the bearing can be expressed by twelve dynamic coefficients of FIG.
However, X, Y: Cartesian axis coordinates, K: Dimensionless spring, C: Dimensionless damping, M: Dimensionless inertia, F: Excitation force, Z: Transfer function, ω: Angular velocity (rad / s), f: Rotation frequency (Hz / s), tan δ: tangent loss or damping capacity, μ: equivalent friction coefficient, ζ: damping ratio, Q: resonance magnification Q factor = 1 / (2ζ).

  The inventors of the present invention have invented a method for examining the stability of the friction whirl that has not been calculated so far by using a program used for analyzing the shaft vibration of the rotor. Using a complex eigenvalue analysis program that can calculate oil whip, etc., as shown in the following paragraphs “0018” and “0019”, a new method of calculating by replacing the friction effect with the coupled spring coefficient of the bearing is used to rotate the rotating shaft Is to analyze the state of hitting. Although it is not possible to analyze the moving state in the gap, it has been confirmed that sufficient accuracy can be obtained practically.

1) Rubber properties Rubber properties are required for stability analysis.
Static springs: Kxx, Kyy, rubber damping: Cxxω = tanδ * Kxx, Cyyω = tanδ * Kyy, tangent loss: tanδ = Cxxω / Kxx.
Although C is necessary for the eigenvalue calculation, since C of rubber changes with ω, C is obtained from C = Cω / 2πf and input.

2) Definition of new Kxy The destabilizing force due to friction is (FU) = μF (μ: friction coefficient, F: radial load). Considering the state where the shaft is in contact with the bearing, it can be expressed as F = KX or F = (K ² + (Cω) ² ) ^1/2 * X, and the destabilizing force is FU = μF = μ * (K ² + (Cω If) ^{2) 1/2} * X or attenuation is small, since the FU = μKX, the Kxy = FU / X = μ * (K 2 + (Cω) 2) 1/2 or .mu.K. Since (K ² + (Cω) ² ) ^1/2 is determined by the rubber, if this is made constant, changing Kxy is equivalent to changing μ. This concept is an unprecedented treatment.

3) Specific Calculation Example In order to explain the effectiveness of the high-damping bearing according to the present invention, a rubber tangent is obtained with a simplified shaft system (FIG. 5B) of the model pump shown in FIG. When the loss (= Cω / Kxx) is 0.1 (normal rubber) and 0.6 (high damping special rubber), the limit Kxy at which the damping ratio (ζ) is negative is obtained by stability analysis. The critical friction coefficient was derived and compared.

  FIG. 4 schematically shows a dry friction whirl stability analysis technique. First, Kxy and -Kyx for rotor dynamics analysis are calculated (step S1). Next, the stability analysis function of the rotor dynamics analysis program is calculated (step S2), thereby obtaining the natural frequency fi and the damping ratio ζi (step S3). An example of a rotor dynamics analysis technique is shown in FIG. This process is repeated (step S4), the natural frequency fi and the damping ratio ζi of the calculation result are plotted (see FIG. 6), the stability limit at which the damping ratio ζi becomes 0 is obtained (step S5), and converted to the friction coefficient μ Then (step S6), the limit friction coefficient μc is obtained (step S7). It can be concluded that if the limiting coefficient of friction μc is greater than the maximum coefficient of friction that the bearing can take, it is sufficiently safe against dry friction whirls.

1) Stability analysis calculation In order to evaluate the stability by changing the friction effect as the values of Kxy and Kyx, change the value of Kxy = -Kyx as follows to obtain the change in stability (damping ratio). It was. Kxy = −5 × 10 ³ , Kxy = −1 × 10 ⁴ , Kxy = −3 × 10 ⁴ , Kxy = −5 × 10 ⁴ , Kxy = −1 × 10 ⁵ , Kxy = −3 × 10 ⁵ , Kxy = FIG. 6 is a graph in which the frequency and damping ratio obtained in each case of −5 × 10 ⁵ and Kxy = −1 × 10 ⁶ (N / m) are plotted with the value of the horizontal axis −Kxy. From FIG. 6, the limit −Kxy and the limit μ at which the dry friction whirl is generated for each tangent loss tan δ (= Cω / Kxx) · mode are as follows.
Cω / Kxx = 0.1
Primary mode limit -Kxy = 1.7 × 10 ⁴ N / m, limit μ = 0.065
Secondary mode limit -Kxy = 2.5 × 10 ⁴ N / m, limit μ = 0.095
Cω / Kxx = 0.6
Primary mode limit -Kxy = 1.3 × 10 ⁵ N / m, limit μ = 0.45
Secondary mode limit -Kxy = 1.5 × 10 ⁵ N / m, limit μ = 0.52

FIG. 18 shows the relationship between the limit μ of the primary mode and the tangent loss tan δ (= Cω / Kxx). Usually, μreal has a maximum value of about 0.2. Therefore, it can be understood that if tangent loss tan δ (= Cω / Kxx) is 0.3 or more, μ _C > μreal and the friction whirl does not occur. .

  By the way, in a shaft system used exceeding the primary critical speed of a vertical pump, if the damping is small, as shown in FIG. 7, a large amplitude vibration is generated when the primary critical speed is passed due to the unbalance of the shaft. However, it may be difficult to continue driving. There is a need for countermeasure technology to realize a shaft system that can be used over the primary critical speed.

  Since the special rubber support bearing of the vertical long pump according to the present invention employs rubber having high damping characteristics, as shown in FIG. 7, the large amplitude vibration generated when the primary dangerous speed is passed is attenuated. It can be expected that the vehicle can be operated safely while being suppressed.

  If other methods, for example, lubricating oil can be used, the tangent loss tan δ (= Cω / Kxx) = 1.0 can be obtained, so that it can be used beyond the primary critical speed due to the damping effect. However, an oil bearing cannot be used when the vertical pump used in water is used at a rotational speed higher than the primary critical speed. Therefore, the bearing according to the present invention can be operated safely and reliably exceeding the primary critical speed.

That is, in the special rubber support bearing for the vertical long pump according to the present invention, the damper inner cylinder is fitted on the bearing inner cylinder that receives the rotation shaft, and the damper member is disposed between the damper inner cylinder and the damper outer cylinder. A bearing box that is interposed and supported by the fixed structure portion of the rotating machine is provided outside the damper outer cylinder. A rubber whose tangent loss of the damper member is equal to or greater than a value obtained by the following method is used. It was determined limit Kxy by the rotor dynamics analysis using the dry friction destabilizing factor derived from the causative friction coefficient μ ho Waal Kxy = -μK = -μ * (K 2 + (Cω) 2) 1/2 Later, the limit friction coefficient μc = limit Kxy / (K ² + (Cω) ² ) ^1/2 is calculated. If this value is larger than the maximum friction coefficient that the bearing can take (μc> μreal), no friction whirl is generated, and if μc <μreal, a friction whirl is generated. A tangent loss tan δ (= Cω / K) such that μc> μreal is obtained, and a rubber that realizes this is employed. The rubber is characterized in that the resonance magnification at the primary critical speed is such that the vibration becomes a small amplitude vibration.

1) Vibration at the time of passing through the first critical speed The resonance magnification Q factor can be obtained from the damping ratio (ζ) when Kxy = 0 and μ = 0 in each tangent loss tan δ (= Cω / Kxx) in the primary mode of FIG. it can.
Cω / Kxx = 0.1:
Primary mode damping ratio (ζ) = 0.024 Resonance magnification Q factor = 20.8
Cω / Kxx = 0.6:

Primary mode damping ratio (ζ) = 0.143 Resonance magnification Q factor = 3.5
FIG. 7 shows the vibration response at each Cω / Kxx when passing through the primary critical speed 350 min ⁻¹ . It can be seen that by using rubber having a high damping characteristic, the Q factor can be reduced to about 1/6, and a characteristic capable of easily overcoming the primary dangerous speed can be obtained.

  Also, bearings supported by rubber with high damping characteristics can be operated in the air without lubrication, but the aforementioned rubber has the property of generating heat when absorbing vibration energy, so the temperature of the rubber rises. As shown in FIG. 2, the rubber softens and the spring constant decreases. In the air operation, a cooling technique that suppresses the temperature rise is necessary so as to ensure the performance of the rubber.

  Therefore, it is preferable that the bearing of the rotary machine according to the present invention further includes a cooling device that can suppress the temperature rise of the rubber (damping member). For the rubber cooling device, methods such as air cooling, heat pipes, and heat transfer using a pure copper flexible conductor can be adopted.

1) Air cooling system A vertical groove for ventilation is provided in the rubber inner cylinder on the surface in contact with the bearing. Examples of the structure are shown in FIGS. In the figure, 10 is a rotating shaft, 11 is a bearing inner cylinder, 12 is a damper inner cylinder having a plurality of longitudinal grooves 12A formed on the inner surface, 13 is a damper outer cylinder, 14 is rubber (damper member), and 15 is a bearing box. , 16 is a bearing sleeve, and 17 is an impeller. During the air operation, the damper 14 is blown and cooled using the fan blow pressure of the impeller 17 and exhausted using a pipe connected to the atmospheric pressure side such as an instrumentation pipe to thereby remove the rubber 14. Can be cooled.

2) Heat Pipe System FIG. 9 shows an example of the structure of a rubber cooling device using the heat pipe system, and the same reference numerals as those in FIG. In the figure, 20 is a heat pipe, 21 is a working fluid, 22 is a steam flow, 23 is a capillary gap material, 24 is an evaporating part, and 25 is a condensing part.

  As shown in FIG. 9 (c), when heat is applied at the evaporation section 24, the heat pipe boiles the working fluid (water, alcohol, etc.) 21, becomes a steam flow 22, and moves to the condensation section 25 at the speed of sound. While the condensation latent heat is released and the external heat is taken away, the condensing unit 25 liquefies the hydraulic fluid 21 that has been cooled from the outside to become the vapor stream 22. The condensed hydraulic fluid 21 returns to the evaporator 24 by the capillary force of the wick (capillary gap material) 23 and repeats this cycle.

  As shown in FIGS. 9 (a) and 9 (b), the rubber is cooled by embedding the evaporating portion 24 of the heat pipe 20 in the rubber 14 so that the rubber 14 is cooled evenly. The circumferential direction and depth direction are adjusted at. The generated steam flow 22 is connected to a fin insertion type heat pipe / heat sink 26 which becomes a condensing portion 25 by extending the heat pipe 20, and is cooled to condense the working fluid 21.

3) Air cooling system A fin-inserted heat pipe / heat sink is installed inside the pump or outside the pump so that the fins can be efficiently cooled using the air flow from the impeller.

4) Heat transfer by pure copper flexible conductor As shown in FIG. 10, one side of the flexible conductor 30 with pure copper crimp terminal is screwed to the lower end of the damper inner cylinder 12 in contact with the bearing inner cylinder 11, The other crimp terminal is attached to the screw hole opened in the underwater bearing box 15 through the groove hole opened on the back side of the mounting flange of the damper outer cylinder 13. Thereby, the heat of the damper inner cylinder 12 and the rubber 14 that rise in temperature due to the heat generated by the bearing can be thermally conducted from the bearing box 15 to the guide vanes 17 through the pure copper flexible conductor 30 to be cooled.

  In FIG. 10, 10 is a rotating shaft, 11 is a bearing inner cylinder, 12 is a damper inner cylinder, 13 is a damper outer cylinder, 14 is a damper rubber (damper member), 15 is an underwater bearing box, 16 is a bearing sleeve, and 17 is a blade. A car 18 is a guide vane.

  By the way, the damper bearing generally uses oil such as a squeeze film oil damper bearing, but a damper bearing that exhibits high damping characteristics is required even in places where oil cannot be used.

  Therefore, in the present invention, a bearing supported by rubber having high damping characteristics can be employed as the damper rubber bearing. That is, according to the present invention, a bearing supported with high damping characteristics is installed immediately below the external shaft joint 40 as shown in FIG. 11, or the main body of the external bearing 40 as shown in FIGS. Is installed so as to be supported by rubber having a high damping characteristic, a damper effect can be obtained, and it can be used to reduce vibration amplitude of the shaft and avoid self-excited vibration such as whirl.

1) Example of external bearing body supported by rubber with high damping characteristics (Fig. 12)
A plurality of round anti-vibration rubbers (damper rubbers) 14 are arranged in a circular shape below the main body of the external bearing 40, and the pump thrust load and the pump weight above the external bearing 40 are supported by the damper rubber 14 in the horizontal direction. The rubber shape is determined so as to be rigid in the vertical direction and flexible in the horizontal direction so that vibration response is possible.

2) An example in which the vertical direction is supported by a support pin and the horizontal direction is supported by a damper rubber (FIG. 14).
The support pin 43 is arranged in a circular shape at the lower part of the body of the external bearing 40 to support the pump thrust load and the pump load above the external bearing 40, and the vibration vibration in the horizontal direction applies a damper rubber to the radial bearing position of the external bearing 40. Place and support.

  Here, as shown in FIG. 13, in the case of a vertical pump, the external bearing 40 is a bearing in which a radial bearing 41 and a thrust bearing 42 are installed as a set on a discharge curved pipe.

〔Concrete example〕
Hereinafter, the present invention will be described in detail based on specific examples. When using a vertical pump with a rated speed of 585 min ^-1 and a speed control range of 80% to 100% (468 min ^{-1 to} 585 min ^-1 ), the critical speed is at 80% speed and dangerous from the operating range. It was necessary to remove the speed. The spring constant of the existing submerged bearing of the pump of this example is 10 ⁶ N / m. However, in the apparatus of this example, the resonance magnification Q factor is improved, the vibration peak is reduced, and the spring constant is 5 × 10 ⁶ N. As a result of taking measures to remove the dangerous speed from the operating range by lowering to / m, the rotational speed control range was widened and smooth operation was possible.
Here, FIG. 15 schematically shows a vibration countermeasure example in the above specific example, and FIG. 16 shows the relationship of the vibration amplitude to the rotation speed when the vibration countermeasure is taken and when it is not taken.

DESCRIPTION OF SYMBOLS 1 Bearing inner cylinder 2 Damper inner cylinder 3 Damper outer cylinder 4 Damper member 5 Bearing box

Claims (5)

A damper inner cylinder is externally fitted to the bearing inner cylinder that receives the rotation shaft, and a damper member is interposed between the damper inner cylinder and the damper outer cylinder, and the fixed structure portion of the vertical pump is disposed outside the damper outer cylinder. A supported bearing box is provided. The characteristics of the damper member are as follows: static spring: K, damping: Cω = tanδ * K, tangent loss: tanδ = Cω / K. The damper member is made of rubber whose tangent loss is not less than the value obtained by the following method. It was determined limit Kxy by the rotor dynamics analysis using the dry friction destabilizing factor derived from the causative friction coefficient μ ho Waal Kxy = -μK = -μ * (K 2 + (Cω) 2) 1/2 Later, the limit friction coefficient μc = limit Kxy / (K ² + (Cω) ² ) ^1/2 is converted. If this value is larger than the maximum friction coefficient [mu] real that the bearing can take ([mu] c> [mu] real), no friction whirl is generated, and if [mu] <[mu] real, a friction whirl is generated. A special rubber support bearing for a long vertical pump characterized by obtaining a tangent loss tan δ (= Cω / K) such that μc> μreal, and adopting a rubber that realizes this. A damper inner cylinder is externally fitted to the bearing inner cylinder that receives the rotating shaft, and a damper member is interposed between the damper inner cylinder and the damper outer cylinder, and is supported on the fixed structure portion of the rotating machine outside the damper outer cylinder. A bearing housing is provided. The characteristics of the damper member are as follows: static spring: K, damping: Cω = tanδ * K, tangent loss: tanδ = Cω / K. The damper member is made of rubber whose tangent loss is not less than the value obtained by the following method. It was determined limit Kxy by the rotor dynamics analysis using the dry friction destabilizing factor derived from the causative friction coefficient μ ho Waal Kxy = -μK = -μ * (K 2 + (Cω) 2) 1/2 Later, the limit friction coefficient μc = limit Kxy / (K ² + (Cω) ² ) ^1/2 is converted. If this value is larger than the maximum friction coefficient [mu] real that the bearing can take ([mu] c> [mu] real), no friction whirl is generated, and if [mu] <[mu] real, a friction whirl is generated. By calculating the tangent loss tan δ (= Cω / K) such that μc> μreal and adopting a rubber that realizes this, the resonance magnification at the primary critical speed becomes a vibration with a small amplitude. Special rubber support bearings for vertical long pumps.   The special rubber support bearing for a vertical long pump according to claim 1 or 2, further comprising a device for cooling the damper inner cylinder and the damper member.   The special rubber support bearing for a vertical long pump according to claim 1 or 2, wherein the tangent loss of the damper member is at least 0.3. A special rubber vibration isolator for a vertical long pump provided on a rotary shaft directly below an external bearing connecting a rotary shaft of a vertical pump and a transmission shaft of a driving machine,
A damper inner cylinder is externally fitted to the bearing inner cylinder that receives the rotating shaft, a damper member is interposed between the damper inner cylinder and the damper outer cylinder, and a fixed structure portion of the vertical pump outside the damper outer cylinder Is provided with a bearing box supported by the housing. The characteristics of the damper member are as follows: static spring: K, damping: Cω = tanδ * K, tangent loss: tanδ = Cω / K. The damper member is made of rubber whose tangent loss is not less than the value obtained by the following method. It was determined limit Kxy by the rotor dynamics analysis using the dry friction destabilizing factor derived from the causative friction coefficient μ ho Waal Kxy = -μK = -μ * (K 2 + (Cω) 2) 1/2 Later, the limit friction coefficient μc = limit Kxy / (K ² + (Cω) ² ) ^1/2 is converted. If this value is larger than the maximum friction coefficient [mu] real that the bearing can take ([mu] c> [mu] real), no friction whirl is generated, and if [mu] <[mu] real, a friction whirl is generated. A special rubber vibration isolator for a vertical long pump characterized by obtaining a tangent loss tan δ (= Cω / K) such that μc> μreal and adopting a rubber that realizes this.

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