Crankshaft axial centering state detection method, device, equipment and storage medium

Abstract

The application discloses a crankshaft axial centering state detection method, device, equipment and storage medium, and relates to the technical field of engines. The crankshaft axial centering state detection method comprises the following steps: determining a first offset of an actual axial position of a crankshaft in a first working condition of a diesel engine relative to an axial centering position; and determining a second offset of the actual axial position of the crankshaft in a second working condition of the diesel engine relative to the axial centering position. Whether the crankshaft is offset and the type of the offset are determined according to the first offset and / or the second offset. Thus, the axial centering state of the crankshaft during the working process of the diesel engine can be detected in real time, so that whether the crankshaft is offset and the type of the offset can be determined, and timely adjustment can be made before wear occurs, so that a serious wear accident can be avoided, and the cost of maintenance and equipment replacement is reduced, and the reliable operation of the diesel engine is ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of engines, in particular to a crankshaft axial centering state detection method, device, equipment and storage medium. BACKGROUND

[0002] During the working process of a diesel engine, the crankshaft will expand axially due to heat. In order to ensure that the crankshaft has room for thermal expansion and does not produce excessive axial movement to cause such faults as cylinder pulling, it is necessary to design a crankshaft thrust clearance. Due to the existence of the crankshaft thrust clearance, the axial position of the crankshaft main journal opening relative to the main bearing seat of the engine body is not fixed. Therefore, when the rear end shaft system and the high elastic installation error are large, and / or the crankshaft and the engine body expand thermally, the crankshaft is prone to axial deviation, thereby causing abnormal wear of the thrust plate. Therefore, it is necessary to detect the axial centering state of the crankshaft.

[0003] A conventional method for detecting the axial centering state of the crankshaft is to use a displacement sensor to detect the axial displacement of the crankshaft, and to determine whether the crankshaft is in the axial centering state according to the change in the axial displacement of the crankshaft. However, this method is a fault detection method that occurs after wear, and cannot detect the centering state in advance. SUMMARY

[0004] The embodiments of the present application provide a crankshaft axial centering state detection method, device, equipment and storage medium to realize real-time detection of the axial centering state of the crankshaft of a diesel engine.

[0005] Technical solution: The crankshaft axial centering state detection method provided by the embodiments of the present application is applied to a diesel engine, and the method comprises:

[0006] determining a first offset of an actual axial position of the crankshaft in a first working condition of the diesel engine relative to an axial centering position;

[0007] determining a second offset of the actual axial position of the crankshaft in a second working condition of the diesel engine relative to the axial centering position;

[0008] determining whether the crankshaft deviates and the type of deviation according to the first offset and / or the second offset.

[0009] In some embodiments, the determination of whether the crankshaft deviates and the type of deviation according to the first offset and / or the second offset comprises:

[0010] determining whether the first offset satisfies a first preset condition, and if the first offset satisfies the first preset condition, the crankshaft deviates and a first type of deviation occurs;

[0011] And / or, judging whether the second offset satisfies a second preset condition, if the second preset condition is satisfied, the crankshaft is offset and a second type of offset occurs.

[0012] In some embodiments, the first preset condition is whether the first offset is greater than a first preset wear warning value.

[0013] The second preset condition is whether the second offset is greater than a second preset wear warning value.

[0014] In some embodiments, the first preset wear warning value is 0.4-0.5 times of a measured thrust clearance of the diesel engine.

[0015] In some embodiments, the second preset wear warning value is determined according to the first preset wear warning value and a thermal expansion amount of the diesel engine body.

[0016] In some embodiments, the first type of offset includes an offset caused by installation error of a rear end shaft system of the crankshaft and / or installation error of a high-elastic coupling.

[0017] The second type of offset includes an offset caused by thermal expansion of the diesel engine body and / or thermal expansion of the crankshaft.

[0018] In some embodiments, the method for determining the first offset includes:

[0019] determining a maximum actual axial displacement of the crankshaft in a first working condition of the diesel engine and a minimum actual axial displacement of the crankshaft in the first working condition of the diesel engine;

[0020] determining the first offset according to half of a sum of the maximum actual axial displacement of the crankshaft in the first working condition of the diesel engine and the minimum actual axial displacement of the crankshaft in the first working condition of the diesel engine.

[0021] In some embodiments, the method for determining the second offset includes:

[0022] determining a maximum actual axial displacement of the crankshaft in a second working condition of the diesel engine and a minimum actual axial displacement of the crankshaft in the second working condition of the diesel engine;

[0023] determining the second offset according to half of a sum of the maximum actual axial displacement of the crankshaft in the second working condition of the diesel engine and the minimum actual axial displacement of the crankshaft in the second working condition of the diesel engine.

[0024] In some embodiments, the first working condition is a low working condition of the diesel engine or an initial running condition, and the second working condition is a high working condition of the diesel engine or a long-time running condition.

[0025] Correspondingly, the application discloses a device for detecting the axial centering state of a crankshaft.

[0026] A first determining module is configured to determine a first offset of the actual axial position of the crankshaft in the first working condition of the diesel engine relative to the axial centering position.

[0027] A second determining module is configured to determine a second offset of the actual axial position of the crankshaft in the second working condition of the diesel engine relative to the axial centering position.

[0028] A judging module is configured to judge whether the crankshaft is offset and the type of the offset according to the first offset and / or the second offset.

[0029] Correspondingly, the application discloses an electronic device, which comprises a memory, a processor and a computer program stored in the memory and capable of running on the processor, and the processor implements the method for detecting the axial centering state of a crankshaft when executing the computer program.

[0030] Correspondingly, the application discloses a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the method for detecting the axial centering state of a crankshaft.

[0031] Advantages: compared with the prior art, the method, device, equipment and storage medium for detecting the axial centering state of a crankshaft, the method for detecting the axial centering state of a crankshaft comprises the following steps: determining a first offset of the actual axial position of the crankshaft in the first working condition of the diesel engine relative to the axial centering position; determining a second offset of the actual axial position of the crankshaft in the second working condition of the diesel engine relative to the axial centering position. The first offset and / or the second offset are used to judge whether the crankshaft is offset and the type of the offset. Thus, the axial centering state of the crankshaft in the working process of the diesel engine can be detected in real time, so as to judge whether the crankshaft is offset and the type of the offset, thereby facilitating timely adjustment before wear occurs, avoiding serious wear accidents, reducing the cost of maintenance and equipment replacement, and ensuring the reliable operation of the diesel engine. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0033] Figure 1is a flow chart of a method for detecting an axial centering state of a crankshaft provided in an embodiment of the present application.

[0034] Figure 2 is a schematic diagram of a device for detecting an axial centering state of a crankshaft provided in an embodiment of the present application.

[0035] Figure 3 is a schematic diagram of a method for detecting an axial centering state of a crankshaft provided in an embodiment of the present application.

[0036] Figure 4 is a schematic diagram of a method for detecting an axial centering state of a crankshaft provided in an embodiment of the present application.

[0037] Figure 5 is a schematic diagram of a device for detecting an axial centering state of a crankshaft provided in an embodiment of the present application.

[0038] Figure 6 is a schematic diagram of an electronic device according to an embodiment of the present application.

[0039] Reference Signs:

[0040] 101 - first determining module; 102 - second determining module; 103 - judging module; 100 - device for detecting an axial centering state of a crankshaft; 1 - rear end shafting; 2 - high-elasticity coupling; 3 - flywheel; 4 - second axial displacement sensor; 5 - first axial displacement sensor; 6 - acquisition system; 7 - computer; 8 - machine body; 9 - thrust piece; 10 - crankshaft. DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0042] It should be understood that although the terms first, second, etc. can be used herein to describe various components, these components should not be limited by these terms. These terms are used to distinguish one component from another. Thus, a first component discussed below could be termed a second component without departing from the teachings of the present application. As used herein, the term "and / or" includes any and all combinations of associated items.

[0043] Those skilled in the art can understand that the drawings are only schematic diagrams of example embodiments, and can not be to scale. The modules or processes in the drawings are not necessarily essential for implementing the present application, and therefore cannot be used to limit the scope of protection of the present application.

[0044] Considering that the crankshaft will expand axially due to heat during the operation of the diesel engine, in order to ensure that the crankshaft has room for thermal expansion and does not produce excessive axial movement to cause such failures as cylinder pulling, it is necessary to design a crankshaft thrust clearance. Due to the existence of the crankshaft thrust clearance, the axial position of the crankshaft main journal opening relative to the main bearing seat of the engine body is not fixed, and the relative axial position is mainly affected by the installation error of the rear end shaft system and the high elastic coupling. If the relative axial position of the rear end shaft system and the high elastic coupling is too large / too small when they are matched and assembled with the diesel engine, the crankshaft will be pushed to the flywheel end / free end, thereby causing the crankshaft thrust surface to be too close to a side thrust piece, which is not conducive to establishing a stable oil film on the thrust piece. In addition, during the long-term high operating condition of the diesel engine, due to the thermal expansion of the crankshaft and the engine body, the axial clearance between the crankshaft thrust surface and a side thrust piece may also be too small. When the crankshaft rotates at high speed in the above state, the lubrication condition of the thrust piece is easily deteriorated, and its axial carrying capacity is reduced. Therefore, by detecting whether the crankshaft is in an axial central state, abnormal wear of the thrust piece can be effectively avoided.

[0045] At present, the conventional detection method for the axial state of the crankshaft is to detect the axial displacement of the crankshaft by using a displacement sensor, and to judge the wear condition of the thrust piece according to the change of the axial displacement of the crankshaft. This method belongs to fault detection after wear occurs, and cannot detect in advance to avoid abnormal wear of the thrust piece caused by installation error of the rear end shaft system and the high elastic coupling. Moreover, as the test proceeds, the thermal expansion of the crankshaft and the engine body will affect the detection accuracy of the displacement sensor, and then affect the accuracy of the crankshaft movement state monitoring.

[0046] Therefore, the embodiment of the present application provides a crankshaft axial central state detection method, device, equipment and storage medium, to realize real-time detection of the axial central state of the crankshaft of the diesel engine, and identify the type of the deviation when the deviation occurs.

[0047] Figure 1 is a flow chart of a crankshaft axial central state detection method provided in the embodiment of the present application. The method can be applied to the process of realizing real-time detection of the state of the crankshaft of the diesel engine in the diesel engine control system. The method can be executed by a crankshaft axial central state detection device, which can be realized by software and hardware, and the device can be configured in the processor or controller of the diesel engine control system.

[0048] Referring to Figure 1 , the method comprises the following steps:

[0049] Step 110, determining a first deviation amount of the actual axial position of the crankshaft in a first operating condition state of the diesel engine relative to the axial central position.

[0050] The first working condition of the diesel engine is a low working condition or a starting condition.

[0051] The axial center position of the crankshaft refers to an ideal installation position or a design position of the crankshaft in the axial direction relative to the main journal on which the thrust plate is installed, at which the axial clearances of the main journal opening of the crankshaft relative to the main bearing seats on both sides of the crankshaft body are equal, and the specific position can be set according to actual conditions and is not limited herein.

[0052] Step 120, determining a second offset of the actual axial position of the crankshaft in the second working condition of the diesel engine relative to the axial center position.

[0053] The second working condition is a high working condition or a long-time running condition.

[0054] Step 130, judging whether the crankshaft is offset and the type of the offset according to the first offset and / or the second offset.

[0055] Specifically, during the running of the diesel engine, the first offset of the crankshaft in the first working condition of the diesel engine and the second offset of the crankshaft in the second working condition of the diesel engine are determined in real time, and the axial centering state of the crankshaft is determined in real time according to the first offset and / or the second offset, so that the axial centering state of the crankshaft can be detected in real time, and timely adjustment can be made before wear occurs, so as to avoid serious wear accidents and reduce the cost of maintenance and equipment replacement.

[0056] In the technical scheme of the embodiment of the present application, the working principle of the crankshaft axial centering state detection method is as follows: Figure 1 First, the first offset of the actual axial position of the crankshaft in the first working condition of the diesel engine relative to the axial center position is determined. Then, the second offset of the actual axial position of the crankshaft in the second working condition of the diesel engine relative to the axial center position is determined. Finally, whether the crankshaft is offset and the type of the offset are judged according to the first offset and / or the second offset. Thus, the axial centering state of the crankshaft during the running of the diesel engine can be detected in real time by the method to determine whether the crankshaft is offset and the type of the offset, so that timely adjustment can be made before wear occurs, serious wear accidents can be avoided, the cost of maintenance and equipment replacement can be reduced, and the reliable running of the diesel engine can be ensured.

[0057] In some embodiments, determining whether the crankshaft is offset and the type of offset according to the first offset amount and / or the second offset amount comprises: determining whether the first offset amount satisfies a first preset condition, if the first preset condition is satisfied, the crankshaft is offset and a first type of offset occurs; and / or, determining whether the second offset amount satisfies a second preset condition, if the second preset condition is satisfied, the crankshaft is offset and a second type of offset occurs.

[0058] The first preset condition is whether the first offset amount is greater than a first preset wear warning value, and the second preset condition is whether the second offset amount is greater than a second preset wear warning value.

[0059] The first preset wear warning value is an abnormally worn thrust plate warning value. The second preset wear warning value is an abnormally worn thrust plate warning value affected by the thermal expansion amount.

[0060] The first preset wear warning value is in the range of 0.4-0.5 times the measured thrust clearance of the diesel engine. Since the first preset wear warning value is affected by the thrust clearance, the thrust clearance range is different for different models, and even for the same model, the measured value of the thrust clearance between different units will also differ, so the first preset wear warning value cannot be generally set as a universal range.

[0061] The second preset wear warning value is determined according to the first preset wear warning value and the thermal expansion amount of the diesel engine body.

[0062] The method for determining the thermal expansion amount of the diesel engine body can be: determining according to the thermal expansion amount of the diesel engine body before and after starting. The thermal expansion amount of the diesel engine body before and after starting can be obtained by a position sensor. For example, the difference between the maximum value before starting and the maximum value after starting of the displacement sensor arranged at the end face of the diesel engine body is calculated.

[0063] The thermal expansion amount of the crankshaft is the second offset amount, which is used for logical judgment with the second preset wear warning value. The method for determining the thermal expansion amount of the crankshaft can be: determining according to the maximum value and the minimum value of the actual axial displacement of the crankshaft affected by the axial thermal expansion of the crankshaft. The maximum value and the minimum value of the actual axial displacement of the crankshaft affected by the axial thermal expansion of the crankshaft can be obtained by a position sensor. For example, the maximum value and the minimum value of the actual axial displacement of the crankshaft affected by the axial thermal expansion of the crankshaft are summed and half of the sum is calculated.

[0064] The specific method for determining the second preset wear warning value can be: calculating according to the difference between the first preset wear warning value and the thermal expansion amount of the diesel engine body.

[0065] In some embodiments, the first type of offset includes an offset caused by installation error of the rear end shaft system of the crankshaft and / or installation error of the high-elasticity coupling; and the second type of offset includes an offset caused by thermal expansion of the diesel engine body and / or thermal expansion of the crankshaft.

[0066] Specifically, during operation of the diesel engine, a first offset amount of the crankshaft in a first working condition of the diesel engine and a second offset amount of the crankshaft in a second working condition of the diesel engine are determined. Then, it is determined whether the first offset amount is greater than a first preset wear warning value. If the first offset amount is greater than the first preset wear warning value, it indicates that the crankshaft is offset, and the offset is caused by installation error of the rear end shaft system of the crankshaft and / or installation error of the high-elasticity coupling. It is also determined whether the second offset amount is greater than a second preset wear warning value. If the second offset amount is greater than the second preset wear warning value, it indicates that the crankshaft is offset, and the offset is caused by thermal expansion of the diesel engine body and / or thermal expansion of the crankshaft. Thus, the axial centering state of the crankshaft can be detected in real time to determine whether the crankshaft is offset and the type of offset, so that timely adjustment can be made before wear occurs, thereby avoiding serious wear accidents, reducing maintenance and equipment replacement costs, and ensuring reliable operation of the diesel engine. Moreover, the method can be used to avoid the problem of axial misalignment of the crankshaft caused by installation error of the rear end shaft system of the diesel engine and the high-elasticity coupling, and the influence of thermal expansion of the crankshaft and the diesel engine body on the axial centering state of the crankshaft during the test process is considered, so that the axial centering state of the crankshaft during operation of the diesel engine can be detected, wear problems caused by axial offset of the crankshaft can be avoided, and reliable operation of the diesel engine can be ensured.

[0067] In some embodiments, the method for determining the first offset amount includes determining an actual axial displacement maximum value of the crankshaft in the first working condition of the diesel engine and an actual axial displacement minimum value of the crankshaft in the first working condition of the diesel engine; and determining the first offset amount according to a sum of the actual axial displacement maximum value of the crankshaft in the first working condition of the diesel engine and the actual axial displacement minimum value of the crankshaft in the first working condition of the diesel engine.

[0068] In some embodiments, the first offset amount is calculated according to half of the sum of the actual axial displacement maximum value of the crankshaft in the first working condition of the diesel engine and the actual axial displacement minimum value of the crankshaft in the first working condition of the diesel engine.

[0069] In some embodiments, the calculation formula of the first offset amount is:

[0070]

[0071] In some embodiments, a max is the actual axial displacement maximum value of the crankshaft in the first working condition of the diesel engine, and a minis the minimum value of the actual axial displacement of the crankshaft in the first working condition of the diesel engine.

[0072] The maximum value of the actual axial displacement of the crankshaft in the first working condition of the diesel engine is determined by detecting the maximum value of the actual axial displacement of the crankshaft in the low working condition of the diesel engine. For example, the maximum value of the actual axial displacement of the crankshaft in the low working condition of the diesel engine is repeatedly detected by the displacement sensor for multiple times (for example, n times, and the specific value of n can be set according to actual conditions, which is not specifically limited herein). The average value of the maximum values of the actual axial displacement of the crankshaft in the low working condition of the diesel engine repeatedly measured for n times is taken as the maximum value of the actual axial displacement of the crankshaft in the first working condition of the diesel engine.

[0073] The minimum value of the actual axial displacement of the crankshaft in the first working condition of the diesel engine is determined by detecting the minimum value of the actual axial displacement of the crankshaft in the low working condition of the diesel engine. For example, the minimum value of the actual axial displacement of the crankshaft in the low working condition of the diesel engine is repeatedly detected by the displacement sensor for multiple times (for example, n times, and the specific value of n can be set according to actual conditions, which is not specifically limited herein). The average value of the minimum values of the actual axial displacement of the crankshaft in the low working condition of the diesel engine repeatedly measured for n times is taken as the minimum value of the actual axial displacement of the crankshaft in the first working condition of the diesel engine.

[0074] In some embodiments, the method for determining the second offset includes: determining the maximum value of the actual axial displacement of the crankshaft in the second working condition of the diesel engine and the minimum value of the actual axial displacement of the crankshaft in the second working condition of the diesel engine; and determining the second offset according to the sum of the maximum value of the actual axial displacement of the crankshaft in the second working condition of the diesel engine and the minimum value of the actual axial displacement of the crankshaft in the second working condition of the diesel engine.

[0075] The specific implementation of the second offset is that the second offset is calculated according to half of the sum of the maximum value of the actual axial displacement of the crankshaft in the second working condition of the diesel engine and the minimum value of the actual axial displacement of the crankshaft in the second working condition of the diesel engine.

[0076] The calculation formula of the second offset is:

[0077]

[0078] wherein a max is the maximum value of the actual axial displacement of the crankshaft in the second working condition of the diesel engine, a min is the minimum value of the actual axial displacement of the crankshaft in the second working condition of the diesel engine.

[0079] Figure 2 is a schematic diagram of a crankshaft axial centering state detection device provided in an embodiment of the present application. For example, please refer to Figure 2, the crankshaft axial centering state detection device comprises a rear end shaft system 1, a high elasticity coupling 2, a flywheel 3, a second axial displacement sensor 4, a first axial displacement sensor 5, an acquisition system 6, a computer 7, a body 8, a thrust piece 9 and a crankshaft 10. The measuring surface of the first axial displacement sensor 5 is the body 8, and the measuring surface of the second axial displacement sensor 4 is the end surface of the flywheel 3. The first axial displacement sensor 5, the second axial displacement sensor 4, the acquisition system 6 and the computer 7 complete data acquisition and recording through data lines.

[0080] Figure 3 is a whole flowchart of a crankshaft axial centering state detection method provided in the embodiment of the application. For example, please refer to Figure 3 , and the specific implementation process of the method is as follows:

[0081] Firstly, in the static state of the diesel engine, the crankshaft is adjusted to the axial centering position, and the zero position of the axial displacement of the crankshaft is set. Specifically, firstly, in the static state of the diesel engine, the pointer of the dial gauge is placed on the end surface of the crankshaft, and the crankshaft is pried to the axial limit position in the direction of the free end and the flywheel end respectively, so that the crankshaft thrust clearance value L is obtained. Then, the crankshaft is pushed towards the free end until the crankshaft thrust surface contacts the thrust piece at the flywheel end, at which time the free end axial limit position is reached. After the crankshaft is axially moved by a distance of L / 2 (the distance L / 2 is determined by the difference between the readings of the dial gauges before and after the movement of the crankshaft), it is considered that the axial clearances of the crankshaft main journal opening relative to the two sides of the body main bearing seat are approximately equal, that is, the crankshaft main journal opening relative to the body main bearing seat is approximately adjusted to the axial centering position in the static state of the diesel engine. Then, the axial displacement sensor is fixedly installed to exclude the interference of the body vibration on the displacement sensor. The first axial displacement sensor 5 in the Figure 2 is aligned with the vertical surface of the body 8 to detect the thermal expansion amount of the body, and the second axial displacement sensor 4 is aligned with the end surface of the flywheel 3 to detect the axial displacement amount of the crankshaft. The indication value of the second axial displacement sensor 4 when the crankshaft 10 is in the axial centering position is set to 0, and the zero position setting of the axial displacement of the crankshaft is completed.

[0082] Secondly, in the initial running state of the diesel engine, the influence of the installation of the rear end shaft system 1 and the high elasticity coupling 2 on the axial centering state of the crankshaft 10 is detected. Specifically, in the initial running state of the diesel engine, whether the crankshaft is still in the axial centering position in the rotating state (i.e. the first working condition state of the diesel engine) is judged by half of the sum of the maximum value and the minimum value of the crankshaft axial displacement curve (i.e. the first offset amount). Since the crankshaft is in a suspended state due to the supporting action of the main bearing bush oil film in the work, the axial installation error of the rear end shaft system and the high elasticity coupling will cause the crankshaft to have the first offset amount. If the first offset amount is greater than the abnormal wear criterion value L of the thrust piece, it is considered that the installation of the rear end shaft system and the high elasticity coupling has caused the crankshaft to deviate from the axial centering position, and the diesel engine needs to be repaired. a(i.e. the first preset wear warning value), it can be determined that the installation error of the rear end shaft system and the high-elastic coupling is too large, which has affected the normal work of the thrust plate, and the diesel engine should be stopped and the axial position of the rear end shaft system and the high-elastic coupling should be adjusted according to the offset direction and distance of the crankshaft relative to the main bearing seat of the engine body, so that the crankshaft is approximately in the axial central position under the running state of the diesel engine.

[0083] Thirdly, the influence of the expansion of the crankshaft and the thermal expansion of the engine body on the axial central state of the crankshaft is detected under the subsequent high working condition and long time running state of the diesel engine. Specifically, first, the axial thermal expansion amount AL of the engine body in the running process of the diesel engine is obtained by the difference between the maximum values of the axial displacement curves of the first axial displacement sensor before and after starting. 机体 Then, the axial thermal expansion amount AL of the crankshaft in the running process of the diesel engine is obtained by taking half of the sum of the maximum value and the minimum value of the axial displacement curve of the second axial displacement sensor under the second working condition of the diesel engine. 曲轴 At the same time, the axial thermal expansion amount AL of the crankshaft in the running process of the diesel engine is obtained by taking half of the sum of the maximum value and the minimum value of the axial displacement curve of the second axial displacement sensor under the second working condition of the diesel engine. 曲轴 That is, the actual offset amount (i.e. the second offset amount) of the crankshaft relative to the axial central position considering the influence of thermal expansion. The second offset amount is operated and judged with the thrust plate abnormal wear criterion value L a '(i.e. the second preset wear warning value), if the second offset amount is greater than the thrust plate abnormal wear criterion value L a ', it indicates that the crankshaft main journal opening is too close to one side of the engine main bearing seat under the influence of thermal expansion, and the operator should be prompted to run at a reduced speed and load to avoid causing the thrust plate working surface to be ablated.

[0084] Therefore, the crankshaft axial central state detection method provided by the embodiment of the application can be used to avoid the problem of the crankshaft axial misalignment caused by the installation deviation of the rear end shaft system and the high-elastic coupling of the diesel engine, and the influence of the thermal expansion of the crankshaft and the engine body on the axial central state of the crankshaft during the test process is considered, so that the axial central state of the crankshaft in the running process of the diesel engine can be detected, the wear problem caused by the axial offset of the crankshaft can be avoided, and the reliable operation of the diesel engine can be ensured.

[0085] Figure 4 is a schematic diagram of a crankshaft axial central state recognition process provided in the embodiment of the application. For example, please refer to Figure 4 The crankshaft axial central state recognition includes the following steps:

[0086] Firstly, the crankshaft is axially centered in the static state of the diesel engine, and the zero position of the axial displacement of the crankshaft is set. Specifically, the crankshaft is jolted in the stopped state of the diesel engine, and the actual maximum axial displacement a max and the actual minimum axial displacement a minThe measured value of the crankshaft thrust clearance is defined as C=a max -a min The second axial displacement sensor value a t is obtained when the crankshaft is jolted to the axial limit of the free end and then jolted to the flywheel end direction until the second axial displacement sensor value is a t At this time, it is considered that the crankshaft is approximately in the axial center position under the static state of the diesel engine, and the second axial displacement sensor value is set to 0.

[0087] The second axial displacement sensor value a t under the theoretical installation state of the diesel engine (at this time, the thrust clearance of the crankshaft relative to the two sides of the thrust piece should be equal) is:

[0088]

[0089] Secondly, the maximum actual axial displacement and the minimum actual axial displacement of the crankshaft under the initial state of the diesel engine are obtained. Specifically, during the low working condition operation stage (i.e., the first working condition state) of the diesel engine, the maximum actual axial displacement a max1 , a max2 , a max3 of the crankshaft under three (this example selects 3, and other numbers can also be selected) complete displacement processes are selected, and the maximum actual axial displacement a max ′ of the crankshaft under the rotating state (i.e., the maximum actual axial displacement of the crankshaft under the first working condition state of the diesel engine) is obtained by calculating the average value. Similarly, the minimum actual axial displacement a min1 , a min2 , a min3 of the crankshaft under three complete displacement processes is selected, and the minimum actual axial displacement a min ′ of the crankshaft under the rotating state (i.e., the minimum actual axial displacement of the crankshaft under the first working condition state of the diesel engine) is obtained.

[0090] The maximum actual axial displacement a max ′ of the crankshaft under the rotating state is:

[0091]

[0092] The minimum actual axial displacement a min ′ of the crankshaft under the rotating state is:

[0093]

[0094] Third, the actual axial position of the crankshaft is obtained based on the maximum and minimum actual axial displacements of the crankshaft under the first operating condition of the diesel engine, and logically judged against the criterion value (i.e., the first preset wear warning value): if the maximum actual axial displacement of the crankshaft under the first operating condition of the diesel engine is a max The absolute value of ′ is less than the minimum actual axial displacement a of the crankshaft under the first operating condition of the diesel engine. min The absolute value of ′ indicates that the actual installation position of the crankshaft has shifted towards the free end relative to its theoretical installation position, and vice versa, it has shifted towards the flywheel end. The amount of shift of the actual axial position of the crankshaft relative to the axial center position is the first offset. When the first offset is greater than the thrust washer abnormal wear criterion value L a If the error message indicates improper installation of the diesel engine's rear shaft system and high-elasticity coupling, resulting in significant axial displacement of the crankshaft, an alarm command will be issued, prompting the operator to stop the engine and adjust the axial position of the rear shaft system and high-elasticity coupling. After restarting the engine, repeat step three until the first offset is less than the abnormal wear alarm value L for the thrust washers. a This indicates that the crankshaft is approximately axially centered under these installation conditions.

[0095] Fourth, obtain the thermal expansion of the crankshaft and engine block under high operating conditions and long-term operation of the diesel engine: by using the maximum values ​​b1 and b2 of the first axial displacement sensor before and after start-up, the thermal expansion ΔL of the engine block before and after start-up of the diesel engine can be obtained. 机体 =b1-b2; The maximum and minimum actual axial displacements of the crankshaft after being affected by the axial thermal expansion of the crankshaft are respectively a max "(i.e., the maximum actual axial displacement of the crankshaft under the second operating condition of the diesel engine) and a min "(That is, the actual minimum axial displacement of the crankshaft under the second operating condition of the diesel engine), is obtained by summing the maximum and minimum values ​​of the axial displacement curve of the second axial displacement sensor under the second operating condition of the diesel engine and taking half of the sum.

[0096]

[0097] Fifth, the actual axial centering state of the crankshaft (i.e., the crankshaft offset under the second operating condition of the diesel engine) is determined by considering the thermal expansion. Specifically, based on the calculated thermal expansion of the crankshaft and the engine block, the axial centering state of the crankshaft under high operating conditions and long-term operation is corrected. The offset of the actual axial position of the crankshaft relative to the axial centering state is then called the second offset. Since the thermal expansion of the engine block is equivalent to reducing the measured value C of the crankshaft thrust clearance, the abnormal wear alarm value for the thrust washers considering the thermal expansion (i.e., the second preset wear warning value) is L. a ′=L a- AL 机体 When the second offset is greater than the second preset wear warning value, it is considered that the lubrication condition of the free end or the flywheel end thrust plate is poor, and the test may cause abnormal wear of the thrust plate at this time. When the above-mentioned situation occurs, an alarm instruction is issued to prompt the operator to run at a reduced speed and load until the second offset is less than the second preset wear warning value, which indicates that the diesel engine can resume high-load test.

[0098] Wherein, L a is a threshold index for judging whether the crankshaft thrust plate has abnormal wear, which can be accurately obtained through bench test, and the method for approximately taking the value is: 0.4-0.5 times the measured thrust clearance of the diesel engine.

[0099] Figure 5 is a schematic structural diagram of a principle of a crankshaft axial centering state detection device provided in the embodiment of the present application. Please refer to Figure 5 The crankshaft axial centering state detection device 100 comprises: a first determination module 101, configured to determine a first offset of an actual axial position of the crankshaft in a first working condition of the diesel engine relative to an axial centering position; a second determination module 102, configured to determine a second offset of the actual axial position of the crankshaft in a second working condition of the diesel engine relative to the axial centering position; and a judgment module 103, configured to judge whether the crankshaft has offset and the type of the offset according to the first offset and / or the second offset.

[0100] The technical scheme of the embodiment of the present application provides a crankshaft axial centering state detection device, which comprises: a first determination module, configured to determine a first offset of an actual axial position of the crankshaft in a first working condition of the diesel engine relative to an axial centering position; a second determination module, configured to determine a second offset of the actual axial position of the crankshaft in a second working condition of the diesel engine relative to the axial centering position; and a judgment module, configured to judge whether the crankshaft has offset and the type of the offset according to the first offset and / or the second offset. Thus, the axial centering state of the crankshaft in the working process of the diesel engine can be detected in real time by the device to judge whether the crankshaft has offset and the type of the offset, so as to facilitate timely adjustment of the offset before wear occurs, avoid serious wear accidents, reduce the cost of maintenance and equipment replacement, and ensure the reliable operation of the diesel engine.

[0101] In some embodiments, the judgment module is further configured to: judge whether the first offset satisfies a first preset condition, and if the first preset condition is satisfied, the crankshaft has offset and a first type of offset occurs; and / or, judge whether the second offset satisfies a second preset condition, and if the second preset condition is satisfied, the crankshaft has offset and a second type of offset occurs.

[0102] In some embodiments, the first preset condition is whether the first offset is greater than a first preset wear warning value; and the second preset condition is whether the second offset is greater than a second preset wear warning value.

[0103] In some embodiments, the first preset wear warning value is in a range of 0.4-0.5 times of the measured thrust clearance of the diesel engine.

[0104] In some embodiments, the second preset wear warning value is determined according to the first preset wear warning value and a thermal expansion amount of the diesel engine body.

[0105] In some embodiments, the first type of offset includes an offset caused by an installation error of the rear-end shaft system of the crankshaft and / or an installation error of the high-elasticity coupling; and the second type of offset includes an offset caused by thermal expansion of the diesel engine body and / or thermal expansion of the crankshaft.

[0106] In some embodiments, the first determining module is further configured to determine a maximum actual axial displacement of the crankshaft in the first working condition of the diesel engine and a minimum actual axial displacement of the crankshaft in the first working condition of the diesel engine; and determine the first offset according to half of a sum of the maximum actual axial displacement of the crankshaft in the first working condition of the diesel engine and the minimum actual axial displacement of the crankshaft in the first working condition of the diesel engine.

[0107] In some embodiments, the second determining module is further configured to determine a maximum actual axial displacement of the crankshaft in the second working condition of the diesel engine and a minimum actual axial displacement of the crankshaft in the second working condition of the diesel engine; and determine the second offset according to half of a sum of the maximum actual axial displacement of the crankshaft in the second working condition of the diesel engine and the minimum actual axial displacement of the crankshaft in the second working condition of the diesel engine.

[0108] In some embodiments, the first working condition is a low working condition or an initial running condition of the diesel engine; and the second working condition is a high working condition or a long-time running condition of the diesel engine.

[0109] Correspondingly, the embodiment of the present application further provides an electronic device, please refer to Figure 6 , Figure 6 a structural diagram of the electronic device of the embodiment of the present application is shown. The electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor executes the computer program to implement the steps of the above-mentioned crankshaft axial centering state detection method. Since the above-mentioned crankshaft axial centering state detection method has been described in detail, it will not be repeated here.

[0110] Correspondingly, the application also provides a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the steps of the above-mentioned crankshaft axial centering state detection method. Since the above-mentioned crankshaft axial centering state detection method has been described in detail, it will not be described here.

[0111] In the above embodiments, the description of each embodiment has its own focus, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0112] The above describes the crankshaft axial centering state detection method, device, equipment and storage medium provided by the embodiments of the application in detail, and the principles and implementation manners of the application are described by applying specific examples. The above embodiment is only used to help understand the technical solutions and core ideas of the application; those skilled in the art should understand that the technical solutions recorded in the above-mentioned embodiments can still be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the application.

Claims

1. A method of detecting a state of axial centering of a crankshaft, characterized by, The method is applied to a diesel engine, and the method comprises: determining a first offset of an actual axial position of a crankshaft relative to an axial center position in a first working condition of the diesel engine; determining a second offset of the actual axial position of the crankshaft relative to the axial center position in a second working condition of the diesel engine; judging whether the crankshaft is offset and the type of offset according to the first offset and / or the second offset; the judging whether the crankshaft is offset and the type of offset according to the first offset and / or the second offset comprises: judging whether the first offset satisfies a first preset condition, if the first preset condition is satisfied, the crankshaft is offset and a first type of offset occurs; and / or, judging whether the second offset satisfies a second preset condition, if the second preset condition is satisfied, the crankshaft is offset and a second type of offset occurs; the first preset condition is whether the first offset is greater than a first preset wear warning value; the second preset condition is whether the second offset is greater than a second preset wear warning value; the second preset wear warning value is determined according to the first preset wear warning value and a thermal expansion amount of a diesel engine body; the first type of offset comprises an offset caused by installation errors of a crankshaft rear end shaft system and / or installation errors of a high-elasticity coupling; the second type of offset comprises an offset caused by thermal expansion of the diesel engine body and / or thermal expansion of the crankshaft.

2. The method of claim 1, wherein The first preset wear warning value is 0.4-0.5 times of a measured thrust clearance of the diesel engine.

3. The method of claim 1, wherein The method for determining the first offset comprises: determining a maximum actual axial displacement of the crankshaft in the first working condition of the diesel engine and a minimum actual axial displacement of the crankshaft in the first working condition of the diesel engine; determining the first offset according to half of a sum of the maximum actual axial displacement of the crankshaft in the first working condition of the diesel engine and the minimum actual axial displacement of the crankshaft in the first working condition of the diesel engine.

4. The method of claim 1, wherein The method for determining the second offset comprises: determining a maximum actual axial displacement of the crankshaft in the second working condition of the diesel engine and a minimum actual axial displacement of the crankshaft in the second working condition of the diesel engine; determining the second offset according to half of a sum of the maximum actual axial displacement of the crankshaft in the second working condition of the diesel engine and the minimum actual axial displacement of the crankshaft in the second working condition of the diesel engine.

5. The method of claim 1, wherein The first working condition is a low working condition of the diesel engine or an initial driving state, and the second working condition is a high working condition of the diesel engine or a long-time running state.

6. A crankshaft axial centering detection device, characterized in that, The device is applied to a diesel engine, and the device comprises: a first determining module configured to determine a first offset of an actual axial position of a crankshaft relative to an axial center position in a first working condition of the diesel engine; a second determining module configured to determine a second offset of the actual axial position of the crankshaft relative to the axial center position in a second working condition of the diesel engine; a judging module configured to judge whether the crankshaft is offset and the type of offset according to the first offset and / or the second offset; The judging module is further configured to judge whether the first offset satisfies a first preset condition, and if the first preset condition is satisfied, the crankshaft is offset and a first type of offset occurs. And / or, judge whether the second offset satisfies a second preset condition, and if the second preset condition is satisfied, the crankshaft is offset and a second type of offset occurs. The first preset condition is whether the first offset is greater than a first preset wear early warning value. The second preset condition is whether the second offset is greater than a second preset wear early warning value. The second preset wear early warning value is determined according to the first preset wear early warning value and the thermal expansion amount of the diesel engine body. The first type of offset includes an offset caused by installation errors of a crankshaft rear end shaft system and / or installation errors of a high-elasticity coupling. The second type of offset includes an offset caused by thermal expansion of the diesel engine body and / or thermal expansion of the crankshaft.

7. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the computer program to implement the crankshaft axial centering state detection method in any one of claims 1-5.

8. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the crankshaft axial centering state detection method in any one of claims 1-5.

Images