Vibration reduction method for reciprocating compressor unit system

Abstract

The invention discloses a vibration reduction method for a reciprocating compressor unit system, and belongs to the technical field of system vibration control. The method comprises the following steps: acquiring working condition parameters under the operation condition of a reciprocating compressor unit system and time domain vibration signals of each vibration measuring point in each testing direction, and obtaining a corresponding spectrogram; establishing a mechanical vibration finite element analysis model of the system according to the design drawing information and the quality and rigidity of equipment in the system, and obtaining the distribution condition of the inherent frequency of the structure; vibration measuring points with vibration amplitudes exceeding a set limit value are recognized through the spectrogram and serve as vibration reduction positions; and corresponding tuned mass dampers are respectively designed and mounted at the vibration reduction positions according to the inherent frequency of the system for vibration reduction. According to the method, the vibration characteristics of the reciprocating compressor unit system put into use in the operation process can be analyzed, targeted vibration reduction measures are provided, and meanwhile the service life, safety and reliability of equipment of the reciprocating compressor unit system can be prolonged.

Description

Technical Field

[0001] The present invention belongs to the technical field of system vibration control, and particularly relates to a vibration reduction method for a reciprocating compressor unit system. Background Art

[0002] The vibration problem of compressor units in industries such as petroleum, chemical, and gas industries is a major problem in the industrial field. The vibration of the compressor unit is mainly caused by equipment rotation and pulsation, and the positions with relatively large vibration mainly occur at the cylinder ends, buffer tank air inlets, buffer tank air outlets, accessory pipelines, etc.

[0003] The existing solutions mainly include: modifying the pipeline diameter, adding pipeline supports, adding orifice plates, etc. These measures all require modifying the compressor unit equipment and have the following problems:

[0004] 1. Long modification cycle, poor reliability, high cost, etc.

[0005] 2. If the modification is improper, it will cause relatively large local stresses in the compressor unit equipment, etc., thus exacerbating the vibration.

[0006] 3. Poor repeatable modification performance.

[0007] On the other hand, since the existing solutions focus on the optimal design and improvement of the equipment structure, in actual production applications, in many cases, the vibration of the compressor unit system equipment cannot be effectively reduced. When the compressor unit system equipment operates under relatively large vibration for a long time, it will cause the equipment life, safety, and reliability to be greatly reduced. Summary of the Invention

[0008] The purpose of the present invention is to provide a vibration reduction method for a reciprocating compressor unit system, which can analyze the vibration characteristics during the operation of the reciprocating compressor unit system that has been put into use, analyze the influence of vibration on the operation of the reciprocating compressor unit system, and based on this, propose targeted vibration reduction measures to prevent resonance from affecting the normal operation of the reciprocating compressor unit system, and at the same time improve the equipment life, safety, and reliability of the reciprocating compressor unit system.

[0009] Specifically, the present invention provides a vibration reduction method for a reciprocating compressor unit system, including:

[0010] Collecting operating condition parameters: Collecting the operating condition parameters of the reciprocating compressor unit system under operating conditions, collecting the time-domain vibration signals of each vibration measuring point of the reciprocating compressor unit system in each test direction, and obtaining the corresponding frequency spectrum diagrams;

[0011] Obtain the natural frequency of the system: According to the information in the design drawings and the mass and stiffness of the equipment in the system, establish a mechanical vibration finite element analysis model of the reciprocating compressor unit system put into use, and obtain the distribution of the structural natural frequencies;

[0012] Determine the vibration damping positions: Identify the vibration measurement points with vibration amplitudes exceeding the set limit values through the spectrogram as the vibration damping positions P1n;

[0013] Install tuned mass dampers: At each vibration damping position, design and install corresponding tuned mass dampers for vibration damping according to the natural frequency of the system.

[0014] Furthermore, the natural frequency of the system also includes the natural frequency of the air column.

[0015] Furthermore, before determining the vibration damping positions, it also includes:

[0016] Establish an air flow pulsation simulation analysis model of the reciprocating compressor unit system put into use; According to the positions of the vibration measurement points, divide each air flow pulsation system in the air flow pulsation simulation analysis model, set corresponding internal nodes, and set boundary nodes at the boundaries of each air flow pulsation system;

[0017] Take the operating condition parameters of the reciprocating compressor unit system under operating conditions as the input of the air flow pulsation analysis model, and calculate the pulsating unbalanced forces of the internal nodes and boundary nodes; Take the pulsating unbalanced forces of the internal nodes and boundary nodes as the excitation force input and apply them to the mechanical vibration finite element analysis model to obtain the forced vibration response of the dynamic excitation force of the reciprocating compressor unit system, and compare the effective value of the vibration amplitude in the obtained forced vibration response of the dynamic excitation force with the set limit value;

[0018] Determining the vibration damping positions also includes: Taking the vibration measurement points with the effective value of the vibration amplitude in the obtained forced vibration response of the dynamic excitation force exceeding the set limit value as the vibration damping positions P2n; Taking the union of the vibration damping positions P1n and the vibration damping positions P2n as all the vibration damping positions that need vibration control.

[0019] Furthermore, divide the reciprocating compressor unit system into each air flow pulsation system in the system air flow pulsation simulation analysis model according to the cylinders.

[0020] Furthermore, the installation of the tuned mass dampers includes:

[0021] In the mechanical vibration finite element analysis model, add corresponding tuned mass damper models at each vibration damping position to obtain the global optimal solutions of the mass, stiffness, and damping coefficients of the tuned mass damper models;

[0022] According to the global optimal solutions of the mass, stiffness and damping coefficient of the tuned mass damper, the tuned mass dampers at each vibration reduction position are designed and installed so that their natural frequencies are equal to or close to the natural frequency of the system.

[0023] Further, when obtaining the global optimal solutions of the mass, stiffness and damping coefficient of the tuned mass damper model, the parameter constraints of the tuned mass damper are defined as: mass ratio 1% - 5%, natural frequency ratio 0.95 - 1, damping ratio 0.05 - 0.2.

[0024] Further, the operating condition parameters include but are not limited to operating speed, gas flow rate, pipeline inlet pressure and exhaust pressure, pipeline inlet temperature and exhaust temperature.

[0025] Further, the vibration amplitude is vibration displacement, vibration velocity and / or vibration acceleration.

[0026] Further, the vibration reduction positions include the cylinder end, the buffer tank inlet, the buffer tank outlet and the attached pipeline of the inlet and outlet.

[0027] Further, the tuned mass damper includes a hoop, an elastic unit, a basic mass unit and an adjustment mass unit;

[0028] The hoop is tightly held on the outer circumference of the inlet and outlet buffer tank or the cylinder end of the compressor unit. The hoop is composed of several arc segments, and each arc segment is connected into a ring. On the outer circumference of the arc segment of the hoop, several elastic units are fixedly installed in an array in a centrosymmetric distribution manner, and the basic mass unit is fixedly installed on the outer side of each elastic unit; one or several adjustment mass units are respectively fixedly installed on each basic mass unit.

[0029] The beneficial effects of the vibration reduction method for the reciprocating compressor unit system of the present invention are as follows:

[0030] The vibration reduction method for the reciprocating compressor unit system of the present invention collects the operating condition parameters of the reciprocating compressor unit system under operating conditions, collects the time-domain vibration signals of each vibration measurement point of the reciprocating compressor unit system in each test direction, and obtains the corresponding spectrogram. The vibration measurement points with vibration amplitudes exceeding the set limit values are identified through the spectrogram as the vibration reduction positions; by installing vibration reduction devices with working frequencies corresponding to the natural frequency of the system at these vibration reduction positions, the resonance at these frequencies is reduced, and the vibration of the reciprocating compressor unit system can be effectively reduced without modifying the structure, with strong adjustability and applicability to all types of reciprocating compressor unit systems.

[0031] The vibration reduction method for the reciprocating compressor unit system of the present invention comprehensively considers the influence of the structural natural frequency and the air column natural frequency on the system vibration, and through the airflow pulsation analysis of the reciprocating compressor unit system that has been put into use, further analyzes the system vibration characteristics, can discover more positions where severe vibration occurs, and prevent the emergence of severe vibration points at new positions after the vibration reduction control is carried out according to the working condition parameters under the collected operating conditions, so as to obtain the optimal vibration reduction effect.

[0032] The vibration reduction method for the reciprocating compressor unit system of the present invention takes the working condition parameters under the operating conditions of the collected compressor unit system as the input of the simulation analysis. Compared with the structural optimization through simulation means in the structural design stage, it can more accurately identify the vibration risks of the system, provide a reasonable basis for vibration reduction treatment, and can solve the vibration problems that emerge after the equipment is manufactured and put into operation although the structure has been optimized.

[0033] By dividing the entire reciprocating compressor unit system into non-interfering airflow pulsation systems according to cylinders for the system airflow pulsation simulation analysis model, the analysis difficulty is reduced.

[0034] The vibration reduction method for the reciprocating compressor unit system of the present invention can effectively reduce the vibration of the compressor unit. The test data of different severe vibration measurement points of a certain type of reciprocating compressor unit system before and after vibration reduction are shown in Table 1.

[0035] Description of the Drawings

[0036] Figure 1 It is a flow chart of an embodiment of the present invention.

[0037] Figure 2 It is a schematic diagram of the layout positions of the vibration measurement points of the reciprocating compressor unit system in an embodiment of the present invention.

[0038] Figure 3 It is a schematic diagram of the layout positions of the vibration measurement points of the first-stage intake and exhaust system in an embodiment of the present invention.

[0039] Figure 4 It is a schematic diagram of the layout positions of the vibration measurement points of the second-stage intake and exhaust system in an embodiment of the present invention.

[0040] Figure 5 It is a schematic diagram of the layout positions of the vibration measurement points of the last-stage intake and exhaust system in an embodiment of the present invention.

[0041] Figure 6 It is a schematic diagram of the layout positions of the vibration measurement points of the vent pipeline in an embodiment of the present invention.

[0042] Figure 7 It is a block diagram of the vibration test system in an embodiment of the present invention.

[0043] Figure 8 It is the vibration test curve of the 12-H direction vibration measurement point in the embodiment of the present invention.

[0044] Figure 9 It is the schematic diagram of the pulsation exceeding ratio of the second pulsation system in the embodiment of the present invention.

[0045] Figure 10 It is the schematic diagram of the pulsation unbalanced force of the first-stage exhaust system in the embodiment of the present invention.

[0046] Figure 11 It is the schematic diagram of the pulsation unbalanced force of the second-stage intake system in the embodiment of the present invention.

[0047] Figure 12 It is the installation schematic diagram of the tuned mass damper of the horizontal compressor unit adopting the embodiment of the present invention.

[0048] Figure 13 It is Figure 12 the schematic diagram of the structure of the tuned mass damper in

[0049] Figure 14 It is Figure 13 the schematic diagram of the elastic unit of

[0050] Figure 15 It is Figure 13 the schematic diagram of the basic mass unit of

[0051] Figure 16 It is Figure 13 the schematic diagram of the adjustment mass unit of

[0052] Identifications in the figure: 1 - inlet and outlet buffer tanks of the compressor unit, 2 - the first type of tuned mass damper, 21 - hoop, 22 - elastic unit, 221 - fixed interface of the elastic unit, 222 - installation interface of the elastic unit, 23 - basic mass unit, 231 - fixed interface of the basic mass unit, 232 - installation interface of the basic mass unit, 24 - adjustment mass unit, 241 - fixed interface of the adjustment mass unit, 3 - the second type of tuned mass damper, 4 - the third type of tuned mass damper, 5 - cylinder end, 6 - compressor unit cylinder block. Specific embodiments

[0053] The present invention will be further described in detail below with reference to the embodiments and the accompanying drawings.

[0054] An embodiment of the present invention is a vibration reduction method for a reciprocating compressor unit system. As Figure 1 shown, the vibration reduction method for the reciprocating compressor unit system of the present invention specifically includes the following steps:

[0055] I. Collect the working condition parameters under the operating conditions.

[0056] Collect the operating condition parameters of the reciprocating compressor unit system under the operating conditions during its commissioning, collect the time-domain vibration signals of each vibration measurement point of the reciprocating compressor unit system in each test direction, and obtain the corresponding spectrograms.

[0057] The operating conditions of the compressor unit system determine the vibration state of the system. When the compressor unit system is operating normally, the operating condition parameters include but are not limited to the operating speed, gas flow rate, pipeline inlet pressure and exhaust pressure, pipeline inlet temperature and exhaust temperature. Usually, acquisition devices for the corresponding operating condition parameters are installed in the already operating compressor unit system. For example, the current operating speed can be directly obtained through the feedback system of the compressor itself, the gas flow rate can be read through a flow meter at the inlet, the pipeline inlet pressure and exhaust pressure can be read through a pressure gauge, and the pipeline inlet temperature and exhaust temperature can be measured through a temperature sensor. For example, in this embodiment, it is collected that the operating frequency of the compressor unit is 960 rpm (16 Hz), the flow rate is 1.8×10 6 m 3 / day, the pipeline inlet pressure is 7 MPa, the pipeline exhaust pressure is 14 MPa, the pipeline inlet temperature is 20 °C, and the pipeline exhaust temperature is 65 °C.

[0058] The time-domain vibration signal is the vibration state shown by the system during operation, and a special test device is required for signal acquisition. The layout of the vibration measurement points of the reciprocating compressor unit system in this embodiment is as Figures 2 to 6 shown. Figure 2 In which CYL#1~CYL#6 are the cylinder numbers, Figures 2 to 6 The circled digital serial numbers (1~75) marked in it are the position numbers for collecting the time-domain vibration signals. Figures 3 to 6 The coordinates in it represent the test directions. A (axial) represents the direction along the axis of the compressor crankshaft, H (horizontal) represents the direction along the movement direction of the compressor cylinder piston, and V (vertical) represents the direction perpendicular to the ground. Three-axis acceleration sensors can be arranged at the vibration measurement point positions for collecting vibration signals (such as vibration acceleration signals), and the collected vibration acceleration signals are saved and processed by a dynamic signal analyzer.

[0059] The test system block diagram is as Figure 7 shown. The vibration measurement points transmit the vibration signals to the analyzer through three-axis acceleration sensors, and the analyzer performs signal conditioning, data processing, records the results and displays them for the vibration signals.

[0060] The vibration amplitude can be vibration displacement, vibration velocity and / or vibration acceleration. In this embodiment, taking vibration velocity as an example, for the vibration measurement points where the vibration velocity of the compressor unit exceeds the set limit value (such as 18 mm / s), it indicates that vibration damping control is required at this position. For example, the time-domain signal vibration data and the corresponding spectrum in the H direction of vibration measurement point 12 are asFigure 8 As shown, the maximum vibration amplitude (i.e., vibration velocity) of this vibration measurement point in the H direction is 23.3 mm / s, which has exceeded the set limit value (18 mm / s), posing a major safety hazard to the safe operation of the unit. The other vibration measurement points will not be elaborated here one by one. The data listed in Table 1 are the over-standard conditions of some vibration measurement points.

[0061] II. Obtain the natural frequency of the system.

[0062] According to the design drawing information, the mass and stiffness of the equipment in the system, establish a mechanical vibration finite element analysis model of the reciprocating compressor unit system put into use, and obtain the distribution of the structural natural frequencies.

[0063] For example, according to the design drawing information of the reciprocating compressor unit system, the mass and stiffness of the equipment in the system, use finite element analysis software (such as ABAQUS) to establish a mechanical vibration finite element analysis model of the reciprocating compressor unit system put into use, and obtain the distribution of the natural frequencies of the currently put into use reciprocating compressor unit system.

[0064] The reciprocating compressor unit system is a relatively complex vibration system, and the natural frequency generally has n orders (n is an integer greater than 1). When one or several orders of the structural natural frequencies coincide with the resonance region of the excitation frequency of the compressor, the pipeline will resonate, and this resonance is called structural resonance. By installing a vibration damping device with a working frequency corresponding to the structural natural frequency, reducing the structural resonance at this structural natural frequency can effectively reduce the vibration of the reciprocating compressor unit system.

[0065] Table 2 shows the calculation results of the first 12-order natural frequencies of the reciprocating compressor unit system in this embodiment. It can be seen from this that the lowest frequency of the compressor unit system is only 10 Hz, the lowest frequency is less than the operating frequency of the compressor (16 Hz), and the 5th and 6th order vibration mode frequencies also fall on the double frequency of the operating frequency of the compressor. Therefore, the system is prone to resonance. Although the natural frequency of the compressor unit system can be optimized through finite element simulation software at the initial stage of the system structure design, due to the complexity of the compressor unit system, it is difficult to optimize the system natural frequency to the best, which results in the occurrence of resonance in the actual operation of the system.

[0066]

[0067] (Optional) III. Establish an air flow pulsation simulation analysis model of the reciprocating compressor unit system put into use, and further analyze the vibration characteristics of the system.

[0068] The gas flows in the pipeline of the compressor unit system, and the shape of the gas column is similar to the outer shape of the pipeline. When a certain order or several orders of the natural frequency of the gas column coincide with the resonance region of the excitation frequency of the compressor, the pipeline will also resonate, and this resonance is called gas column resonance. The common result of gas column resonance and structural resonance is to cause severe vibration of the system. Therefore, in order to better eliminate the possibility of severe vibration, the natural frequency of the system includes the natural frequency of the gas column and the natural frequency of the structure.

[0069] Preferably, in another embodiment, according to the drawing information, equipment information, gas composition and overall layout of the reciprocating compressor unit system, an air flow pulsation simulation analysis model of the reciprocating compressor unit system put into use can be established through acoustic simulation software (such as Bentley Puls), and the natural frequency of the gas column can be obtained.

[0070] Preferably, in another embodiment, by performing air flow pulsation analysis on the reciprocating compressor unit system that has been put into use, the vibration characteristics of the system are further analyzed, specifically including:

[0071] 3-1) Establish an air flow pulsation simulation analysis model of the reciprocating compressor unit system put into use; according to the position of the vibration measurement points, divide each air flow pulsation system in the air flow pulsation simulation analysis model, set corresponding internal nodes to obtain the acoustic wave propagation characteristics at these internal nodes, and set boundary nodes at the boundaries of each air flow pulsation system in the system air flow pulsation simulation analysis model.

[0072] An air flow pulsation simulation analysis model of the reciprocating compressor unit system put into use can be established according to the drawing information, equipment information, gas composition and overall layout of the reciprocating compressor unit system through acoustic simulation software (such as Bentley Puls).

[0073] Since the cylinder is the demarcation point of the air flow pulsation system and each air flow pulsation system does not interfere with each other and can be analyzed independently, preferably, the entire reciprocating compressor unit system is divided into each air flow pulsation system in the system air flow pulsation simulation analysis model according to the cylinders, which reduces the analysis difficulty.

[0074] Such as Figure 2 In the shown compressor system, it is divided into 6 pulsation systems, namely the first pulsation system for the first-stage intake, the second pulsation system for the first-stage exhaust and the second-stage intake, the third pulsation system for the second-stage exhaust and the final-stage intake, the fourth pulsation system for the final-stage exhaust, the fifth pulsation system for the first-stage intake manifold, and the sixth pulsation system for the final-stage exhaust manifold.

[0075] 3-2) Use the operating condition parameters of the reciprocating compressor unit system in actual operation as the input of the gas flow pulsation analysis model to calculate the pulsating unbalanced forces of the internal nodes and boundary nodes; use the pulsating unbalanced forces of the internal nodes and boundary nodes as the input of the excitation force, apply them to the mechanical vibration finite element analysis model, obtain the forced vibration response of the dynamic excitation force of the reciprocating compressor unit system, and compare the effective value of the vibration amplitude in the obtained forced vibration response of the dynamic excitation force with the set limit value.

[0076] The vibration amplitude can be vibration displacement, vibration velocity, and / or vibration acceleration. For example, in this embodiment, when the vibration velocity exceeds the set limit value (18 mm / s), it is considered that the vibration is severe and there is a safety hazard to the normal operation of the unit.

[0077] Use the operating condition parameters of the reciprocating compressor unit system in actual operation collected in Step 1 as the input of the gas flow pulsation analysis model. The acoustic simulation software can automatically calculate the pulsation values of the model nodes in the frequency domain, and can also accurately calculate the pulsating unbalanced forces through the pulsation values. To evaluate the pulsation characteristics of the system, the gas flow pulsation analysis results can be compared with the requirements of API 618 standard. API 618 is a standard for the design, manufacture, procurement, installation, operation, and maintenance of reciprocating compressors and their auxiliary equipment used in the petroleum, chemical, and natural gas industries, and is an important reference for reciprocating compressor-related activities. Figures 9 to 11 For the calculation results obtained by using the operating condition parameters of the compressor unit system in actual operation collected in Step 1 as the input of the gas flow pulsation analysis model, the peak-to-peak value of the pulsation of the first-stage exhaust and second-stage intake systems (i.e., the second pulsation system) is 2.95 times the API 618 standard value, and the pulsating unbalanced force also exceeds the corresponding standard value requirements. It can be seen that there is abnormal vibration caused by gas flow pulsation in the reciprocating compressor unit system in actual operation. Other pulsation systems are also carried out according to the same analysis mode and will not be elaborated here one by one.

[0078] Using the mechanical vibration analysis model to analyze the forced vibration response of the dynamic excitation force of the system can more objectively reflect the vibration situation of the compressor unit system.

[0079] The exciting force is generally the unbalanced force caused by air flow pulsation and the gas force in the cylinder. The pulsating unbalanced forces of each internal node and boundary node obtained from the above air flow pulsation analysis are used as the excitation forces and input into the finite element analysis model of the mechanical vibration of the reciprocating compressor unit system in operation. Table 3 shows the effective value response of the system vibration velocity after the excitation force is applied to the reciprocating compressor unit system. The results show that the vibration amplitudes of the first-stage intake buffer tank and its attached pipelines, and the first-stage exhaust buffer tank and its attached pipelines are relatively large, and the vibration velocities of the first-stage intake buffer tank and the first-stage exhaust buffer tank both exceed the requirement of the set limit value (18 mm / s), posing a safety hazard to the normal operation of the unit.

[0080]

[0081] Therefore, it can be seen that optimizing the structure through simulation means in the structural design stage of the reciprocating compressor unit system achieves vibration reduction based on theory. However, after the equipment is manufactured and put into operation, the vibration problems exposed cannot be identified before production. Part of the reason is that there are deviations between the input information used in the structural design stage and the actual operation. Therefore, by using the actual working state of the compressor unit system obtained in Step 1 as the input for simulation analysis, the vibration risks of the system can be more accurately identified, providing a reasonable basis for vibration reduction treatment.

[0082] IV. Determine the vibration reduction positions.

[0083] The vibration reduction positions refer to the areas where the vibration measuring points with vibration amplitudes exceeding the set limit values are located in the compressor unit system.

[0084] Identify the vibration measuring points with vibration amplitudes exceeding the set limit values through the spectrogram described in Step 1 as the vibration reduction positions P1n. For example, in Step 1, through data processing of all vibration measuring points, the vibration measuring points with the maximum vibration velocity exceeding the set limit value (18 mm / s) can be identified through the spectrogram and used as the vibration reduction positions, and these vibration reduction positions are denoted as P1n. Vibration reduction control must be carried out on the vibration reduction positions P1n because they are problems existing in actual operation.

[0085] Preferably, in another embodiment, the vibration measuring points with the effective values of the vibration amplitudes in the forced vibration response of the dynamic exciting force obtained through the system air flow pulsation in Step 3 exceeding the set limit values are used as the vibration reduction positions P2n. For example, the internal nodes or boundary nodes with the effective values of the vibration velocity exceeding the set limit values are used as the vibration reduction positions P2n. The union of the vibration reduction positions P1n and the vibration reduction positions P2n is used as all the vibration reduction positions that require vibration control. According to the vibration limit requirements of the compressor unit system, the vibration velocities of all the treated vibration reduction positions should not be greater than the set limit value (18 mm / s).

[0086] The vibration reduction positions P2n and P1n may have intersections or differences, and the vibration reduction positions in P2n that are different from P1n are recorded as P2x. The vibration reduction position P2x also needs to be controlled, because after the vibration reduction position P1n is controlled, the vibration occurring at the vibration reduction position P2x will become prominent in actual situations, forming a new vibration bad point. Therefore, in the present invention, the union of P1n and P2n is used as all the vibration reduction positions that need vibration control, so that the best vibration reduction effect can be obtained.

[0087] In this embodiment, the identified vibration reduction positions include the cylinder end, the buffer tank air inlet, the buffer tank exhaust port, and the auxiliary pipes of the air inlet and exhaust ports.

[0088] 5. Install the tuned mass damper.

[0089] At each vibration reduction position, a corresponding tuned mass damper is designed and installed according to the natural frequency of the system to reduce vibration.

[0090] Since the compressor system is already in operation, if it is shut down for structural optimization to solve the vibration problem, it will not only affect the output capacity, but also consume higher costs and time for the transformation. It should be pointed out that structural transformation measures cannot completely overcome the vibration problem of the system, and improper transformation will cause new vibration problems.

[0091] In the present invention, a corresponding tuned mass damper is designed and installed at each vibration reduction position to reduce vibration. As a vibration reduction device, the tuned mass damper does not require modification of the original system structure, can be quickly installed and disassembled, and has an adjustable tuning frequency. It is a better choice for vibration control of the compressor unit system. Specifically, it includes:

[0092] 5-1) In the mechanical vibration finite element analysis model, a corresponding tuned mass damper model is added at each vibration reduction position to obtain a global optimal solution of the mass, stiffness, and damping coefficient of the tuned mass damper model.

[0093] Optimization software (such as HyperStudy) can be used for joint simulation, and the genetic optimization algorithm provided by the software can be used to achieve global optimization and find the global optimal solution for the mass, stiffness and damping coefficient of the tuned mass damper.

[0094] In the global optimization, the parameter constraints of the tuned mass damper are defined as follows: the mass ratio is between 1% and 5%, the natural frequency ratio is between 0.95 and 1, and the damping ratio is between 0.05 and 0.2. Among them, the mass ratio refers to the ratio of the mass of the tuned mass damper to the mass of the vibration-damping system; the natural frequency ratio refers to the ratio of the natural frequency of the tuned mass damper to the natural frequency of the vibration-damping system, and the ratio of stiffness to mass is equal to the square of the natural frequency; the damping ratio refers to the ratio of the damping coefficient of the tuned mass damper to the critical damping coefficient of the vibration-damping system. The goal of global optimization is to minimize the maximum value of the vibration velocity at all vibration-damping positions, and the global optimal solutions of the mass, stiffness, and damping coefficient of the tuned mass damper will be obtained.

[0095] 5-2) Design and install the tuned mass dampers at each vibration-damping position according to the global optimal solutions of the mass, stiffness, and damping coefficient of the tuned mass damper.

[0096] According to the optimization results of the tuned mass damper parameters, considering the structural characteristics of the vibration-damping positions, design and manufacture the structure of the tuned mass damper and install it on the compressor unit system. Figure 12 It is a horizontal compressor unit, which is a specific implementation case of a reciprocating compressor unit. Among them, the first type of tuned mass damper 2 and the second type of tuned mass damper 3 for vibration damping are installed on the inlet and outlet air buffer tanks 1 of the horizontal compressor unit, and the third type of tuned mass damper 4 for vibration damping is installed and arranged at the end 5 of the compressor unit cylinder.

[0097] As Figure 13 shown, the first type of tuned mass damper 2 includes a hoop 21, an elastic unit 22, a basic mass unit 23, and an adjustment mass unit 24; it is used to control the inlet and outlet air buffer tank 1 of the compressor unit or the end 5 of the compressor unit cylinder.

[0098] The hoop 21 is tightly held on the outer circumference of the inlet and outlet air buffer tank 1 or the end 5 of the cylinder of the compressor unit. The hoop 21 is composed of several arc segments, and each arc segment is connected into a ring. A number of elastic units 22 arranged in an array in a centrosymmetric distribution manner are fixedly installed on the outer side of the hoop 21, a basic mass unit 23 is fixedly installed on the outer side of each elastic unit 22, and one or several adjustment mass units 24 are respectively fixedly installed on each basic mass unit 23.

[0099] As Figure 14 shown, the elastic unit 22 is provided with an elastic unit installation interface 222, and the basic mass unit 23 is provided with a basic mass unit fixing interface 231. The basic mass unit fixing interface 231 cooperates with the elastic unit installation interface 22 to fix the basic mass unit 23 on the elastic unit 22.

[0100] As Figure 15 and Figure 16As shown in the figure, the basic mass unit 23 is provided with a basic mass unit installation interface 232; the adjustment mass unit 24 is provided with an adjustment mass unit fixing interface 241. The adjustment mass unit fixing interface 241 cooperates with the basic mass unit installation interface 232 to fix a plurality of adjustment mass units 24 on the outer sides of a plurality of basic mass units 23.

[0101] When the first type of tuned mass damper 2 works, the basic mass unit 23 and the adjustment mass unit 24 vibrate relative to the hoop 21 together with the elastic unit 22, absorbing the vibration energy of the inlet and outlet gas buffer tank 1 of the compressor unit and the cylinder end 5. Each basic mass unit 23 and adjustment mass unit 24 vibrates with the first type of tuned mass damper 2, so that multiple vibration directions can be taken into account, and adjustment is convenient. The best vibration parameters can be matched more conveniently and accurately, so that the best vibration control effect can be produced.

[0102] The number of elastic units 22 can be adjusted. The installation direction and position of the elastic unit 22 can be adjusted according to the vibration control direction. For example, it can be distributed along the circumferential surface of the hoop 21, or radially distributed on each of the inlet and outlet gas buffer tank 1 of the compressor unit or the cylinder end 5, or axially distributed along the inlet and outlet gas buffer tank 1 of the compressor unit or the cylinder end 5. By adjusting the number, material, shape, installation direction and position of the elastic unit, the performance related to vibration such as elastic stiffness, damping and mass can be adjusted, and the best vibration parameters can be accurately matched, so that the best vibration control effect can be produced.

[0103] For the first type of tuned mass damper 2, the hoop is tightly held on the outer side of the inlet and outlet gas buffer tank 1 of the compressor unit or the cylinder end 5, without the need to transform the equipment, which is convenient for implementation. The installation and implementation have little impact on the object to be vibration-controlled, and can effectively reduce the vibration of the inlet and outlet gas buffer tank 1 of the compressor unit or the cylinder end 5.

[0104] For the first type of tuned mass damper 2, the hoop, elastic unit, basic mass unit and adjustment mass unit all adopt modular design, and can be flexibly configured according to the vibration conditions of the equipment, quickly solving the problem of excessive vibration in multiple directions of the equipment. By adjusting the number, material, shape and direction of the elastic unit, basic mass unit and adjustment mass unit, the performance related to vibration such as elasticity, damping and mass can be adjusted, and the best vibration parameters can be accurately matched, so that the best vibration control effect can be produced.

[0105] According to Step 1, collect the working condition parameter data of the reciprocating compressor unit system installed with the tuned mass damper under the operating conditions, and compare the key vibration measurement points before and after vibration reduction. The data comparison is shown in Table 1, and the results show that: the vibration reduction measures of the tuned mass damper meet the system vibration reduction requirements, and the vibration reduction method of the present invention ensures the stability, safety and reliability of the unit operation.

[0106] The vibration reduction method for a reciprocating compressor unit system of the present invention collects the operating condition parameters of the reciprocating compressor unit system under the operating conditions, collects the time-domain vibration signals of each vibration measurement point of the reciprocating compressor unit system in each test direction, and obtains the corresponding spectrogram. The vibration measurement points with vibration amplitudes exceeding the set limit values are identified through the spectrogram as the vibration reduction positions. By installing vibration reduction devices with working frequencies corresponding to the natural frequencies of the system at these vibration reduction positions, resonance at these frequencies can be reduced, and the vibration of the reciprocating compressor unit system can be effectively reduced without modifying the structure.

[0107] The vibration reduction method for a reciprocating compressor unit system of the present invention comprehensively considers the influence of the structural natural frequency and the air column natural frequency on the system vibration, and further analyzes the system vibration characteristics through the air flow pulsation analysis of the reciprocating compressor unit system that has been put into use, so as to discover more positions where severe vibration occurs, prevent the emergence of severe vibration points at new positions after vibration reduction control based on the collected operating condition parameters, and thus obtain the optimal vibration reduction effect.

[0108] The vibration reduction method for a reciprocating compressor unit system of the present invention uses the operating condition parameters of the compressor unit system collected as the input for simulation analysis. Compared with optimizing the structure through simulation means in the structural design stage, it can more accurately identify the vibration risks of the system, provide a reasonable basis for vibration reduction treatment, and solve the vibration problems that emerge after the equipment is manufactured and put into operation although the structure has been optimized.

[0109] By dividing the entire reciprocating compressor unit system into non-interfering air flow pulsation systems according to the cylinders, the analysis difficulty is reduced.

[0110] Although the present invention has been disclosed above with preferred embodiments, the embodiments are not used to limit the present invention. Any equivalent changes or modifications made without departing from the spirit and scope of the present invention also belong to the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the content defined by the claims of this application.

Claims

1. A vibration damping method for a reciprocating compressor unit system, characterized in that Including: Collecting operating condition parameters during operation: Collecting the operating condition parameters of the reciprocating compressor unit system under the operating conditions when it is put into use, collecting the time-domain vibration signals of each vibration measurement point of the reciprocating compressor unit system in each test direction, and obtaining the corresponding spectrogram; Obtaining the system natural frequency: According to the design drawing information, the mass and stiffness of the equipment in the system, establishing a mechanical vibration finite element analysis model of the reciprocating compressor unit system put into use, and obtaining the distribution of the structural natural frequency; Determining the vibration damping position: Identifying the vibration measurement points with vibration amplitudes exceeding the set limit value through the spectrogram as the vibration damping positions P1n; Installing tuned mass dampers: At each vibration damping position, respectively designing and installing corresponding tuned mass dampers for vibration damping according to the system natural frequency.

2. The vibration damping method for the reciprocating compressor unit system according to claim 1, characterized in that, The system natural frequency also includes the air column natural frequency.

3. The vibration damping method for the reciprocating compressor unit system according to claim 1, characterized in that, Before the determination of the vibration damping position, it also includes: Establishing an air flow pulsation simulation analysis model of the reciprocating compressor unit system put into use; According to the positions of the vibration measurement points, dividing each air flow pulsation system in the air flow pulsation simulation analysis model, setting corresponding internal nodes, and setting boundary nodes at the boundaries of each air flow pulsation system; Taking the operating condition parameters of the reciprocating compressor unit system under the operating conditions as the input of the air flow pulsation analysis model, calculating the pulsation unbalanced forces of the internal nodes and boundary nodes; Taking the pulsation unbalanced forces of the internal nodes and boundary nodes as the excitation force input, applying them to the mechanical vibration finite element analysis model, obtaining the forced vibration response of the dynamic excitation force of the reciprocating compressor unit system, and comparing the effective value of the vibration amplitude in the obtained forced vibration response of the dynamic excitation force with the set limit value; The determination of the vibration damping position also includes: Taking the vibration measurement points with the effective value of the vibration amplitude in the obtained forced vibration response of the dynamic excitation force exceeding the set limit value as the vibration damping positions P2n; Taking the union of the vibration damping positions P1n and the vibration damping positions P2n as all the vibration damping positions that need vibration control.

4. The vibration damping method for a reciprocating compressor unit system according to claim 3, characterized in that, Dividing the reciprocating compressor unit system into each air flow pulsation system in the system air flow pulsation simulation analysis model according to the cylinders.

5. The vibration damping method for a reciprocating compressor unit system according to any one of claims 1-4, characterized in that, The installation of the tuned mass dampers includes: In the mechanical vibration finite element analysis model, adding corresponding tuned mass damper models at each vibration damping position to obtain the global optimal solutions of the mass, stiffness, and damping coefficient of the tuned mass damper models; According to the global optimal solutions of the mass, stiffness, and damping coefficient of the tuned mass damper, designing and installing the tuned mass dampers at each vibration damping position so that its natural frequency is equal to or close to the system natural frequency.

6. The vibration damping method for a reciprocating compressor unit system according to claim 5, characterized in that, When obtaining the global optimal solutions of the mass, stiffness, and damping coefficient of the tuned mass damper model, defining the parameter constraints of the tuned mass damper as: mass ratio 1% - 5%, natural frequency ratio 0.95 - 1, damping ratio 0.05 - 0.

2.

7. The vibration damping method for the reciprocating compressor unit system according to any one of claims 1-4, characterized in that, The operating condition parameters include but are not limited to operating speed, gas flow rate, pipeline inlet pressure and exhaust pressure, pipeline inlet temperature and exhaust temperature.

8. The vibration damping method for a reciprocating compressor unit system according to any one of claims 1-4, characterized in that, The vibration amplitude is vibration displacement, vibration velocity and / or vibration acceleration.

9. The vibration damping method for the reciprocating compressor unit system according to any one of claims 1-4, characterized in that, The vibration damping positions include the cylinder end, the inlet of the buffer tank, the outlet of the buffer tank, and the auxiliary pipelines of the inlet and outlet.

10. The vibration damping method for a reciprocating compressor unit system according to any one of claims 1-4, characterized in that, The tuned mass damper includes a hoop, an elastic unit, a basic mass unit, and an adjustment mass unit; The hoop is tightly held on the outer circumference of the inlet and outlet buffer tank or the cylinder end of the compressor unit. The hoop is composed of several arc segments, and the arc segments are connected into a ring. On the outer circumference of the arc segments of the hoop, several elastic units are fixedly installed in an array composed of a central symmetry distribution method. The basic mass unit is fixedly installed on the outer side of each elastic unit; one or several adjustment mass units are respectively fixed on each basic mass unit.

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