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

Abstract

The invention discloses a crankshaft axial centering state detection method, device and equipment and a 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 state of a diesel engine relative to an axial centering position; and determining a second offset of the actual axial position of the crankshaft in the second working condition state of the diesel engine relative to the axial center position. And according to the first offset and / or the second offset, whether the crankshaft deviates or not and the deviation type are judged. Therefore, through the method, 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 deviates or not and judge the deviation type, so that the deviation can be adjusted in time before abrasion occurs, serious abrasion accidents are avoided, and the service life of the diesel engine is prolonged. Therefore, maintenance and equipment replacement cost is reduced, and reliable operation of the diesel engine is guaranteed.

Description

Technical Field

[0001] The present application relates to the field of engine technology, and in particular to a method, device, equipment and storage medium for detecting the axial centering state of a crankshaft. Background Art

[0002] During the operation of the 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 cylinder pulling and other faults, it is necessary to design the 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 undergo thermal expansion, the crankshaft axial offset is easy to occur, resulting in abnormal wear of the thrust plate. Therefore, it is necessary to detect the axial centering state of the crankshaft.

[0003] The 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 determine whether the crankshaft is in the axial centering state based on the change in the axial displacement of the crankshaft. However, this method is a fault detection after wear occurs, and it is impossible to detect the centering state in advance. Summary of the invention

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

[0005] Technical solution: A method for detecting the axial centering state of a crankshaft according to an embodiment of the present application is applied to a diesel engine, and the method comprises:

[0006] Determine a first offset of an actual axial position of the crankshaft relative to an axial center position under a first operating state of the diesel engine;

[0007] Determine a second offset of an actual axial position of the crankshaft relative to an axial center position under a second operating state of the diesel engine;

[0008] Whether the crankshaft is offset and the type of offset are determined according to the first offset and / or the second offset.

[0009] In some embodiments, judging whether the crankshaft is offset and the type of offset according to the first offset and / or the second offset includes:

[0010] Determining 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;

[0011] And / or, it is determined 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 to 0.5 times the actual 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 the thermal expansion amount of the diesel engine body.

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

[0017] The second type of deviation includes: deviation caused by thermal expansion of the diesel engine block and / or thermal expansion of the crankshaft.

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

[0019] Determine a maximum actual axial displacement of the crankshaft under a first operating condition of the diesel engine and a minimum actual axial displacement of the crankshaft under the first operating condition of the diesel engine;

[0020] The first offset is determined according to half of the sum of a maximum value of the actual axial displacement of the crankshaft under the first operating state of the diesel engine and a minimum value of the actual axial displacement of the crankshaft under the first operating state of the diesel engine.

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

[0022] Determine the maximum actual axial displacement of the crankshaft under the second operating state of the diesel engine and the minimum actual axial displacement of the crankshaft under the second operating state of the diesel engine;

[0023] The second offset is determined according to half of the sum of a maximum value of the actual axial displacement of the crankshaft under the second operating state of the diesel engine and a minimum value of the actual axial displacement of the crankshaft under the second operating state of the diesel engine.

[0024] In some embodiments, the first operating state is a low operating state or an initial start-up state of the diesel engine, and the second operating state is a high operating state or a long-term operation state of the diesel engine.

[0025] Accordingly, a crankshaft axial centering state detection device described in an embodiment of the present application is applied to a diesel engine, and the device includes:

[0026] A first determination module, used to determine a first offset of an actual axial position of the crankshaft relative to an axial center position under a first operating state of the diesel engine;

[0027] A second determination module, used to determine a second offset of an actual axial position of the crankshaft relative to an axial center position under a second operating state of the diesel engine;

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

[0029] Correspondingly, an electronic device described in an embodiment of the present application includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the crankshaft axial centering state detection method described above is implemented.

[0030] Accordingly, a computer-readable storage medium described in an embodiment of the present application stores a computer program thereon, and when the computer program is executed by a processor, the crankshaft axial centering state detection method as described above is implemented.

[0031] Beneficial effects: Compared with the prior art, the crankshaft axial centering state detection method, device, equipment and storage medium of the embodiment of the present application, the crankshaft axial centering state detection method includes: determining the first offset of the actual axial position of the crankshaft in the first working state of the diesel engine relative to the axial centering position; determining the second offset of the actual axial position of the crankshaft in the second working state of the diesel engine relative to the axial centering position. Determine whether the crankshaft is offset and the type of offset according to the first offset and / or the second offset. Therefore, the method can realize real-time detection of the axial centering state of the crankshaft during the operation of the diesel engine to determine whether the crankshaft is offset and the type of offset, which is conducive to timely adjustment of the offset before wear occurs, avoiding serious wear accidents, thereby reducing the cost of maintenance and equipment replacement, and ensuring the reliable operation of the diesel engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

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

[0034] Figure 2 It is a schematic diagram of a crankshaft axial centering state detection device provided in an embodiment of the present application;

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

[0036] Figure 4 It is a schematic diagram of a crankshaft axial centering state identification process provided in an embodiment of the present application;

[0037] Figure 5 It is a principle structure block diagram of a crankshaft axial centering state detection device provided in an embodiment of the present application;

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

[0039] Reference numerals:

[0040] 101-first determination module; 102-second determination module; 103-judgment module; 100-crankshaft axial centering state detection device; 1-rear end shaft system; 2-high elastic coupling; 3-flywheel; 4-second axial displacement sensor; 5-first axial displacement sensor; 6-acquisition system; 7-computer; 8-machine body; 9-thrust plate; 10-crankshaft. DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with 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 of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0042] It should be understood that although the terms first, second, etc. may 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 component. Therefore, the first component discussed below can be referred to as the second component without departing from the teachings of the concepts of the present application. As used herein, the term "and / or" includes any one of the associated listed items and all combinations of one or more.

[0043] Those skilled in the art will appreciate that the drawings are only schematic diagrams of example embodiments and may not be to scale. The modules or processes in the drawings are not necessarily required to implement 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 cylinder pulling and other faults, it is necessary to design the 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 its relative axial position is mainly affected by the installation error of the rear-end shaft system and high-elastic coupling. If the relative axial position of the rear-end shaft system, high elasticity and diesel engine is too large / too small when matched and assembled, the crankshaft will be pushed to the flywheel end / free end, causing the crankshaft thrust surface to be too close to the thrust plate on one side, which is not conducive to establishing a stable oil film on the thrust plate. In addition, during the long-term high-operating condition operation of the diesel engine, due to the influence of the thermal expansion of the crankshaft and the engine body, the axial clearance between the crankshaft thrust surface and the thrust plate on one side may be too small. When the crankshaft rotates at high speed in the above state, it is very easy to cause the lubrication condition of the thrust plate to deteriorate and reduce its axial load-bearing capacity. Therefore, by detecting whether the crankshaft is in an axially centered state, abnormal wear of the thrust plate can be effectively avoided.

[0045] At present, the conventional detection method for the axial state of the crankshaft is to use a displacement sensor to detect the axial displacement of the crankshaft, and judge the wear of the thrust plate according to the change of the axial displacement of the crankshaft. This method belongs to fault detection after the wear occurs, and it is impossible to detect in advance to avoid abnormal wear of the thrust plate caused by the rear-end shaft system and high-elastic installation errors. In addition, as the test proceeds, the thermal expansion of the crankshaft and the engine body will affect the detection accuracy of the displacement sensor, and thus affect the accuracy of the crankshaft motion state monitoring.

[0046] In view of this, the embodiments of the present application provide a crankshaft axial centering state detection method, device, equipment and storage medium to achieve real-time detection of the axial centering state of the crankshaft of a diesel engine and identify the type of offset when an offset is detected.

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

[0048] See also Figure 1 , the method comprises the following steps:

[0049] Step 110: Determine a first offset of an actual axial position of the crankshaft relative to an axial center position under a first operating state of the diesel engine.

[0050] The first operating state of the diesel engine is a low operating state or an initial start-up state of the diesel engine.

[0051] Among them, the axial center position of the crankshaft refers to the ideal installation position or design position of the crankshaft in the axial direction relative to the main journal for installing the thrust plate. At this time, the axial clearance of the crankshaft main journal opening relative to both sides of the main bearing seat of the engine body is equal. The specific position can be set according to actual conditions and is not specifically limited here.

[0052] Step 120: Determine a second offset of the actual axial position of the crankshaft relative to the axial center position under the second operating state of the diesel engine.

[0053] The second operating state is a high operating state or a long operating state of the diesel engine.

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

[0055] Specifically, during the operation of the diesel engine, by determining in real time a first offset of the crankshaft when the diesel engine is in a first operating condition, and a second offset when the diesel engine is in a second operating condition, and based on the first offset and / or the second offset, it is possible to determine in real time whether an axial centering state of the crankshaft has shifted, and the type of the shift that has occurred, thereby achieving real-time detection of the axial centering state of the crankshaft, thereby facilitating timely adjustments to the shift before wear occurs, thereby avoiding serious wear accidents, and thereby reducing the cost of maintenance and equipment replacement.

[0056] In the technical solution of the embodiment of the present application, the working principle of the crankshaft axial centering state detection method is as follows: Figure 1 First, determine the first offset of the actual axial position of the crankshaft in the first working state of the diesel engine relative to the axial center position. Then, determine the second offset of the actual axial position of the crankshaft in the second working state of the diesel engine relative to the axial center position. Finally, determine whether the crankshaft is offset and the type of offset based on the first offset and / or the second offset. Therefore, this method can realize real-time detection of the axial centering state of the crankshaft during the operation of the diesel engine to determine whether the crankshaft is offset and the type of offset, which is conducive to making timely adjustments to the offset before wear occurs, avoiding serious wear accidents, thereby reducing the cost of maintenance and equipment replacement, and ensuring the reliable operation of the diesel engine.

[0057] In some embodiments, determining whether the crankshaft is offset and the type of offset is determined based on the first offset and / or the second offset, including: determining whether the first offset satisfies a first preset condition; if so, the crankshaft is offset and a first type of offset occurs; and / or determining whether the second offset satisfies a second preset condition; if so, the crankshaft is offset and a second type of offset occurs.

[0058] 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.

[0059] The first preset wear warning value is an abnormal wear warning value of the thrust washer, and the second preset wear warning value is an abnormal wear warning value of the thrust washer affected by thermal expansion.

[0060] The value range of the first preset wear warning value is 0.4 to 0.5 times the actual thrust clearance of the diesel engine. Since the first preset wear warning value is affected by the thrust clearance, the thrust clearance ranges of different models are different, and even for the same model, the thrust clearance actual measured values ​​between different machines will also be different, so the first preset wear warning value cannot be generally set to a universal range.

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

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

[0063] The crankshaft thermal expansion is the second offset, which is used for logical judgment with the second preset wear warning value. The method for determining the crankshaft thermal expansion can be: determining it according to the maximum and minimum values ​​of the actual axial displacement of the crankshaft after being affected by the axial thermal expansion of the crankshaft. The maximum and minimum values ​​of the actual axial displacement of the crankshaft after being affected by the axial thermal expansion of the crankshaft can be obtained by detecting the position sensor. For example, it is calculated by summing the maximum and minimum values ​​of the actual axial displacement of the crankshaft after being affected by the axial thermal expansion of the crankshaft and taking half of it.

[0064] The specific method for determining the second preset wear warning value may be: calculating the value based on 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: offset caused by installation error of the crankshaft rear end shaft system and / or installation error of the high elastic coupling; the second type of offset includes: offset caused by thermal expansion of the diesel engine body and / or thermal expansion of the crankshaft.

[0066] Specifically, during the operation of the diesel engine, the first offset of the crankshaft in the first working state of the diesel engine and the second offset of the crankshaft in the second working state of the diesel engine are determined. Then, it is determined whether the first offset is greater than the first preset wear warning value. If the first offset is greater than the first preset wear warning value, it means that the crankshaft is offset, and the offset is caused by the installation error of the rear end shaft system of the crankshaft and / or the installation error of the high elastic coupling. It is determined whether the second offset is greater than the second preset wear warning value. If the second offset is greater than the second preset wear warning value, it means that the crankshaft is offset, and the offset is caused by the thermal expansion of the diesel engine body and / or the thermal expansion of the crankshaft. In this way, 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, which is conducive to timely adjustment of the offset before wear occurs, avoiding serious wear accidents, thereby reducing the cost of maintenance and equipment replacement, and ensuring the reliable operation of the diesel engine. This method can also be used to avoid the problem of axial misalignment of the crankshaft caused by installation deviations of the rear-end shaft system and high-elastic coupling of the diesel engine, and considers the influence of thermal expansion of the crankshaft and engine body on the axial centering state of the crankshaft during the test. Thus, the axial centering state of the crankshaft during the operation of the diesel engine can be detected to avoid wear problems caused by axial deviation of the crankshaft, thereby ensuring the reliable operation of the diesel engine.

[0067] In some embodiments, the method for determining the first offset includes: determining the maximum actual axial displacement of the crankshaft under the first operating condition of the diesel engine and the minimum actual axial displacement of the crankshaft under the first operating condition of the diesel engine; determining the first offset based on the sum of the maximum actual axial displacement of the crankshaft under the first operating condition of the diesel engine and the minimum actual axial displacement of the crankshaft under the first operating condition of the diesel engine.

[0068] The first offset is specifically implemented as follows: the first offset is calculated based on half of the sum of the actual maximum axial displacement of the crankshaft under the first operating state of the diesel engine and the actual minimum axial displacement of the crankshaft under the first operating state of the diesel engine.

[0069] The calculation formula of the first offset is:

[0070]

[0071] Among them, a max ′ is the actual maximum axial displacement of the crankshaft in the first working state of the diesel engine, a min' is the minimum actual axial displacement of the crankshaft in the first working state of the diesel engine.

[0072] The method for determining the maximum value of the actual axial displacement of the crankshaft under the first working condition of the diesel engine is as follows: by detecting the maximum value of the actual axial displacement of the crankshaft under the low working condition of the diesel engine. For example, the maximum value of the actual axial displacement of the crankshaft under the low working condition of the diesel engine is repeatedly detected by the displacement sensor for multiple times (for example, n times, the specific value of n can be set according to the actual situation and is not specifically limited here), and the average value of the maximum value of the actual axial displacement of the crankshaft under the low working condition of the diesel engine measured repeatedly for n times is used as the maximum value of the actual axial displacement of the crankshaft under the first working condition of the diesel engine.

[0073] The method for determining the minimum value of the actual axial displacement of the crankshaft under the first working condition of the diesel engine is as follows: by detecting the minimum value of the actual axial displacement of the crankshaft under the low working condition of the diesel engine. For example, the minimum value of the actual axial displacement of the crankshaft under the low working condition of the diesel engine is repeatedly detected by the displacement sensor for multiple times (for example, n times, the specific value of n can be set according to the actual situation and is not specifically limited here), and the average value of the minimum value of the actual axial displacement of the crankshaft under the low working condition of the diesel engine measured repeatedly for n times is used as the minimum value of the actual axial displacement of the crankshaft under the first working condition of the diesel engine.

[0074] In some embodiments, the method for determining the second offset includes: determining the maximum actual axial displacement of the crankshaft under the second operating condition of the diesel engine and the minimum actual axial displacement of the crankshaft under the second operating condition of the diesel engine; determining the second offset based on the sum of the maximum actual axial displacement of the crankshaft under the second operating condition of the diesel engine and the minimum actual axial displacement of the crankshaft under the second operating condition of the diesel engine.

[0075] The second offset is specifically implemented as follows: the second offset is calculated based on half of the sum of the actual maximum axial displacement of the crankshaft under the second operating state of the diesel engine and the actual minimum axial displacement of the crankshaft under the second operating state of the diesel engine.

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

[0077]

[0078] Among them, a max ″ is the actual maximum axial displacement of the crankshaft in the second working state of the diesel engine, a min ″ is the minimum actual axial displacement of the crankshaft in the second operating state of the diesel engine.

[0079] Figure 2 Schematic diagram of a crankshaft axial centering state detection device provided in an embodiment of the present application. Figure 2The crankshaft axial centering state detection device includes a rear end shaft system 1, a high elastic coupling 2, a flywheel 3, a second axial displacement sensor 4, a first axial displacement sensor 5, a collection system 6, a computer 7, a body 8, a thrust plate 9 and a crankshaft 10. Among them, 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. Among them, the first axial displacement sensor 5, the second axial displacement sensor 4, the collection system 6 and the computer 7 complete data collection and recording through a data line.

[0080] Figure 3 is a schematic diagram of the overall process of a crankshaft axial centering state detection method provided in an embodiment of the present application. Figure 3 The specific implementation process of this method is as follows:

[0081] First, when the diesel engine is static, adjust the crankshaft to the axial center position and set the crankshaft axial displacement to zero. Specifically, first, when the diesel engine is stopped, press the dial indicator pointer against the crankshaft end face, and pry the crankshaft toward the free end and the flywheel end to the axial limit respectively to obtain the crankshaft thrust clearance value L. Then push the crankshaft toward the free end until the crankshaft thrust surface contacts the thrust plate at the flywheel end. At this time, the free end axial limit is reached. In this state, move the crankshaft axially toward the flywheel end by a distance of L / 2 (the L / 2 distance is determined by the difference in dial indicator readings before and after the crankshaft moves). It is considered that the axial clearances of the crankshaft main journal opening relative to both sides of the engine main bearing seat are approximately equal, that is, when the diesel engine is static, the crankshaft main journal opening is approximately adjusted to the axial center position relative to the engine main bearing seat. Then, fix and install the axial displacement sensor to eliminate the interference of engine body vibration on the displacement sensor. Figure 2 The first axial displacement sensor 5 is aligned with the vertical surface of the engine body 8 to detect the thermal expansion of the engine body, the second axial displacement sensor 4 is aligned with the end surface of the flywheel 3 to detect the axial displacement of the crankshaft, and the indication of the second axial displacement sensor 4 when the crankshaft 10 is in the axial center position is set to 0, completing the crankshaft axial displacement zero position setting.

[0082] Second, when the diesel engine is in the initial state of operation, detect the impact of the installation of the rear-end shaft system 1 and the high-elastic coupling 2 on the axial centering state of the crankshaft 10. Specifically, when the diesel engine is in the initial state of operation, half of the sum of the maximum and minimum values ​​of the crankshaft axial displacement curve (i.e., the first offset) is used to determine whether the crankshaft is still in the axial center position in the rotating state (i.e., the first working state of the diesel engine) (half of the sum of the maximum and minimum values ​​in the axial center position should be approximately zero). Since the crankshaft is in a suspended state due to the support of the main bearing oil film during operation, the axial installation error of the rear-end shaft system and the high-elastic coupling will cause the crankshaft to have a first offset. If the first offset is greater than the abnormal wear criterion value L of the thrust plate. a(i.e. the first preset wear warning value), it can be judged that the installation error of the rear-end shaft system and the high-elastic coupling is too large and has affected the normal operation of the thrust plate. The engine should be shut down 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 center position when the diesel engine is running.

[0083] Third, in the subsequent high-operating conditions and long-term operation of the diesel engine, the influence of the crankshaft expansion and the thermal expansion of the engine body on the axial centering state of the crankshaft is detected. Specifically, first, the axial thermal expansion of the engine body during the operation of the diesel engine is obtained by the difference in the maximum value of the axial displacement curve of the first axial displacement sensor before and after startup. 机体 Then, the axial thermal expansion △L of the crankshaft during the operation 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 working condition of the diesel engine and taking half of it. 曲轴 , while the axial thermal expansion △L 曲轴 This is the actual offset of the crankshaft relative to the axial center position after considering the influence of thermal expansion (i.e., the second offset). The second offset is combined with the abnormal wear criterion value L of the thrust plate considering the influence of thermal expansion. a ′ (i.e., the second preset wear warning value) is used for calculation and judgment. If the second offset is greater than the abnormal wear criterion value L of the thrust plate, a ′, indicating that the crankshaft main journal is too close to one side of the main bearing seat of the engine body due to thermal expansion, which prompts the operator to reduce the speed and load to avoid ablation failure of the thrust washer working surface.

[0084] It can be seen from this that the crankshaft axial centering state detection method provided in the embodiment of the present application can be used to avoid the problem of crankshaft axial non-centering caused by the installation deviation of the rear end shaft system and the high elastic coupling of the diesel engine, and takes into account the influence of the thermal expansion of the crankshaft and the engine body on the axial centering state of the crankshaft during the test. Therefore, the axial centering state of the crankshaft during the operation of the diesel engine can be detected to avoid wear problems caused by axial deviation of the crankshaft, thereby ensuring the reliable operation of the diesel engine.

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

[0086] First, the crankshaft is axially centered when the diesel engine is static, and the crankshaft axial displacement zero position is set. Specifically, the crankshaft is pried when the diesel engine is stopped, and the actual maximum axial displacement a of the crankshaft in the static state of the diesel engine is measured by the second axial displacement sensor. max and the actual minimum axial displacement a min, the measured value of crankshaft thrust clearance is defined as C = a max -a min , and further obtain the second axial displacement sensor indication value a under the theoretical installation state of the diesel engine (at this time, the thrust clearance of the crankshaft relative to the thrust plates on both sides should be equal) t . Pry the crankshaft to the axial limit position at the free end, and then pry the crankshaft toward the flywheel end until the second axial displacement sensor indicates a. t At this time, it is considered that the crankshaft is approximately in the axial center position when the diesel engine is static, and the indication of the second axial displacement sensor is set to 0.

[0087] Among them, the second axial displacement sensor indication value a under the theoretical installation state of the diesel engine (at this time, the thrust clearance of the crankshaft relative to the thrust plates on both sides should be equal) t for:

[0088]

[0089] Second, obtain the maximum and minimum actual axial displacements of the crankshaft in the initial state of the diesel engine. Specifically, in the low-operating state of the diesel engine (i.e., the first operating state), select the maximum actual axial displacements a of the crankshaft in three (here, 3 are selected as an example, and other numbers can also be selected) complete swaying processes. max1 、a max2 、a max3 , the actual maximum axial displacement a of the crankshaft under rotation is obtained by calculating the average value max ′ (i.e., the maximum actual axial displacement of the crankshaft under the first working condition of the diesel engine). Similarly, the minimum actual axial displacement a of the crankshaft under three complete displacement processes is selected. min1 、a min2 、a min3 , and obtain the minimum actual axial displacement a of the crankshaft under rotation min ' (i.e. the minimum actual axial displacement of the crankshaft under the first operating condition of the diesel engine).

[0090] Among them, the actual maximum axial displacement a of the crankshaft under rotation max 'for:

[0091]

[0092] Among them, the actual minimum axial displacement a of the crankshaft under rotation min 'for:

[0093]

[0094] Third, the actual axial position state of the crankshaft is obtained according to the actual maximum axial displacement of the crankshaft under the first working condition of the diesel engine and the actual minimum axial displacement of the crankshaft under the first working condition of the diesel engine, and a logical judgment is made with the criterion value (i.e., the first preset wear warning value): if the actual maximum axial displacement of the crankshaft under the first working condition of the diesel engine is a max The absolute value of ′ is less than the minimum actual axial displacement a of the crankshaft in the first working state of the diesel engine. min The absolute value of ' indicates that the actual installation position of the crankshaft is offset toward the free end relative to its theoretical installation position, and vice versa, it is offset toward the flywheel end. The offset 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 abnormal wear criterion value L of the thrust plate a When the engine is restarted, repeat the third step until the first offset is less than the abnormal wear alarm value L of the thrust washer. a , indicating that the crankshaft is approximately axially centered under this installation condition.

[0095] Fourth, obtain the thermal expansion of the crankshaft and the engine body under high working conditions and long-term operation of the diesel engine: the maximum value of the first axial displacement sensor before and after startup b 1 and b 2 , and then get the thermal expansion of the diesel engine before and after startup △L 机体 =b 1 -b 2 ; The maximum and minimum values ​​of the actual axial displacement of the crankshaft after being affected by the axial thermal expansion of the crankshaft are a max ″ (i.e. the actual maximum axial displacement of the crankshaft in the second working state of the diesel engine) and a min ″ (i.e., the actual minimum axial displacement of the crankshaft under the second working condition of the diesel engine), the maximum and minimum values ​​of the axial displacement curve of the second axial displacement sensor under the second working condition of the diesel engine are summed and half is taken to obtain the crankshaft thermal expansion:

[0096]

[0097] Fifth, the actual axial centering state of the crankshaft under the influence of thermal expansion is detected based on the thermal expansion (i.e., the offset of the crankshaft under the second operating condition of the diesel engine). Specifically, based on the calculated thermal expansion of the crankshaft and the thermal expansion of the engine body, the axial centering state of the crankshaft under high operating conditions and long-term operation of the diesel engine is corrected. At this time, the offset of the actual axial position of the crankshaft relative to the axial centering state is the second offset. Since the thermal expansion of the engine body is equivalent to reducing the measured value C of the crankshaft thrust clearance, the abnormal wear alarm value of the thrust plate under the influence of thermal expansion (i.e., the second preset wear warning value) is L a ′=L a -ΔL 机体 When the second offset is greater than the second preset wear warning value, it is considered that the lubrication condition of the thrust plate at the free end or the flywheel end is poor. Continuing the test at this time may cause abnormal wear of the thrust plate. When the above situation occurs, an alarm command is issued to prompt the operator to reduce the speed and load until the second offset is less than the second preset wear warning value, indicating that the diesel engine can resume high-load testing.

[0098] Among them, L a In order to determine the threshold indicator for whether abnormal wear of the crankshaft thrust plate occurs, this indicator can be accurately obtained through bench testing, and the approximate value is taken as: 0.4 to 0.5 times the actual measured thrust clearance of the diesel engine.

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

[0100] The technical solution of the embodiment of the present application provides a crankshaft axial centering state detection device, including: a first determination module, used to determine the first offset of the actual axial position of the crankshaft in the first working state of the diesel engine relative to the axial centering position; a second determination module, used to determine the second offset of the actual axial position of the crankshaft in the second working state of the diesel engine relative to the axial centering position; a judgment module, used to judge whether the crankshaft is offset and the type of offset according to the first offset and / or the second offset. Therefore, the device can realize real-time detection of the axial centering state of the crankshaft during the operation of the diesel engine to judge whether the crankshaft is offset and the type of offset, so as to facilitate timely adjustment of the offset before wear occurs, avoid causing serious wear accidents, and thus 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 also used to: judge whether the first offset satisfies a first preset condition. If so, the crankshaft is offset and a first type of offset occurs; and / or judge whether the second offset satisfies a second preset condition. If so, the crankshaft is 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; 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 ranges from 0.4 to 0.5 times the actual 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 the thermal expansion amount of the diesel engine body.

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

[0106] In some embodiments, the first determination module is also used to: determine the maximum actual axial displacement of the crankshaft under the first operating condition of the diesel engine and the minimum actual axial displacement of the crankshaft under the first operating condition of the diesel engine; determine the first offset based on half of the sum of the maximum actual axial displacement of the crankshaft under the first operating condition of the diesel engine and the minimum actual axial displacement of the crankshaft under the first operating condition of the diesel engine.

[0107] In some embodiments, the second determination module is also used to: determine the maximum actual axial displacement of the crankshaft under the second operating condition of the diesel engine and the minimum actual axial displacement of the crankshaft under the second operating condition of the diesel engine; determine the second offset based on half of the sum of the maximum actual axial displacement of the crankshaft under the second operating condition of the diesel engine and the minimum actual axial displacement of the crankshaft under the second operating condition of the diesel engine.

[0108] In some embodiments, the first operating state is a low operating state or an initial start state of the diesel engine, and the second operating state is a high operating state or a long-term operation state of the diesel engine.

[0109] Accordingly, the present application also provides an electronic device, see Figure 6 , Figure 6 The structure diagram of the electronic device of the embodiment of the present application is illustrated. The electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the above-mentioned crankshaft axial centering state detection method are implemented. Since the crankshaft axial centering state detection method is described in detail above, it will not be repeated here.

[0110] Accordingly, the embodiment of the present application further provides a computer-readable storage medium on which a computer program is stored, and when the computer program is executed by a processor, the steps of the above-mentioned crankshaft axial centering state detection method are implemented. Since the above-mentioned crankshaft axial centering state detection method is described in detail, it will not be repeated here.

[0111] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0112] The above describes in detail the crankshaft axial centering state detection method, device, equipment and storage medium provided in the embodiments of the present application, and uses specific examples to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the technical solution and core idea of ​​the present application; ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents; and these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the present application.

Claims

1. A method for detecting the axial centering state of a crankshaft, characterized in that: Applied to a diesel engine, the method comprises: Determine a first offset of an actual axial position of the crankshaft relative to an axial center position under a first operating state of the diesel engine; Determine a second offset of an actual axial position of the crankshaft relative to an axial center position under a second operating state of the diesel engine; Whether the crankshaft is offset and the type of offset are determined according to the first offset and / or the second offset.

2. The method for detecting the axial centering state of a crankshaft according to claim 1, characterized in that: The step of judging whether the crankshaft is offset and the type of offset according to the first offset and / or the second offset includes: Determining 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, it is determined 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.

3. The method for detecting the axial centering state of a crankshaft according to claim 2, characterized in that: 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.

4. The method for detecting the axial centering state of a crankshaft according to claim 3, characterized in that: The first preset wear warning value is 0.4 to 0.5 times the actual measured thrust clearance of the diesel engine.

5. The method for detecting the axial centering state of a crankshaft according to claim 3, characterized in that: 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.

6. The method for detecting the axial centering state of a crankshaft according to claim 2, characterized in that: The first type of offset includes: offset caused by installation error of the crankshaft rear end shaft system and / or installation error of the high elastic coupling; The second type of deviation includes: deviation caused by thermal expansion of the diesel engine block and / or thermal expansion of the crankshaft.

7. The method for detecting the axial centering state of a crankshaft according to claim 1, characterized in that: The method for determining the first offset includes: Determine a maximum actual axial displacement of the crankshaft under a first operating condition of the diesel engine and a minimum actual axial displacement of the crankshaft under the first operating condition of the diesel engine; The first offset is determined according to half of the sum of a maximum actual axial displacement of the crankshaft under the first operating state of the diesel engine and a minimum actual axial displacement of the crankshaft under the first operating state of the diesel engine.

8. The method for detecting the axial centering state of a crankshaft according to claim 1, characterized in that: The method for determining the second offset includes: Determine the maximum actual axial displacement of the crankshaft under the second operating state of the diesel engine and the minimum actual axial displacement of the crankshaft under the second operating state of the diesel engine; The second offset is determined according to half of the sum of a maximum value of the actual axial displacement of the crankshaft under the second operating state of the diesel engine and a minimum value of the actual axial displacement of the crankshaft under the second operating state of the diesel engine.

9. The method for detecting the axial centering state of a crankshaft according to claim 1, characterized in that: The first operating state is a low operating state or an initial start-up state of the diesel engine, and the second operating state is a high operating state or a long-term operation state of the diesel engine.

10. A crankshaft axial centering state detection device, characterized in that: Applied to a diesel engine, the device comprises: A first determination module, used to determine a first offset of an actual axial position of the crankshaft relative to an axial center position under a first operating state of the diesel engine; A second determination module, used to determine a second offset of an actual axial position of the crankshaft relative to an axial center position under a second operating state of the diesel engine; The judging module is used to judge whether the crankshaft is offset and the type of offset according to the first offset and / or the second offset.

11. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the crankshaft axial centering state detection method according to any one of claims 1 to 9 is implemented.

12. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the crankshaft axial centering state detection method according to any one of claims 1 to 9 is implemented.

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