High-speed high-power diesel engine body main bearing stud stretching tool and method

Abstract

The invention discloses a high-speed and high-power diesel engine body main bearing stud stretching tool and method in the technical field of engine part assembling, the tool comprises a fixing assembly, the fixing assembly comprises a base and compression bolts, and the compression bolts are installed on the two sides of the base in a penetrating mode. A second compression nut on a second double-end stud on the outer side is synchronously tightened, then a main bearing stud on the outer side is stretched, a first compression nut is rotated to the contact face of the upper end of a supporting piece, and the pre-tightening force of the main bearing stud on the outer side can be kept; then a second pressing nut on the first double-end stud on the inner side is synchronously tightened through an executing mechanism, stretching and pre-tightening of the main bearing stud on the inner side are completed, the first pressing nut on the main bearing stud on the inner side is rotated to the contact face of the upper end of the bearing cover, and then the pre-tightening force of the main bearing stud on the outer side can be kept; and therefore, the multiple groups of main bearing studs on the inner side and the outer side respectively keep corresponding and consistent pre-tightening force.

Description

Technical Field

[0001] This invention relates to the field of engine component assembly technology, specifically a high-speed, high-power diesel engine block main bearing stud stretching tool and method. Background Technology

[0002] The current fastening method for the main bearing studs of a certain V-type 10-cylinder diesel engine block is as follows: First, insert the main bearing stud into the upper crankcase. Second, pass the bearing cap through the main bearing stud and install it onto the upper crankcase. Third, screw the clamping nut onto the main bearing stud. Fourth, pre-tighten the inner clamping nut to 50 N·m and sew the upper crankcase and bearing cap together. Fifth, pre-tighten the clamping nut by a 150° rotation. Sixth, repeat steps four and five to pre-tighten the outer clamping nut. After this step, the engine block and bearing cap are sewn together.

[0003] Using the above method to sew the upper crankcase and bearing cover has the following disadvantages:

[0004] First: In the fourth step of the current pre-tightening method, when pre-tightening the clamping nut to 50 N·m, the surface roughness of the threads of each main bearing stud and nut varies, and the roughness of the bearing cap surface and support surface in contact with the clamping nut also varies slightly. This results in different friction coefficients between the friction pairs when pre-tightening to 50 N·m. At the same pre-tightening of 50 N·m, the rotation angle of the clamping nut varies. The difference in rotation angle leads to different clamping forces provided by each clamping nut. This causes inconsistencies in the bottom hole dimensions of the six bearing holes in the V-type 10-cylinder diesel engine block components. Inconsistent bottom hole dimensions will seriously affect the service life of the engine.

[0005] Second: Due to the need for three stitching processes during the machining and assembly of engine block components, specifically the upper crankcase and bearing cap, the following three stitching procedures apply: the first stitching occurs during the boring of the bearing hole in the upper crankcase; the second stitching occurs after the bearing is installed to facilitate measurement of the bearing hole data; and the third stitching occurs during crankshaft installation. This unique requirement for multiple stitching processes for the upper crankcase and bearing cap, coupled with the current preload method of 50 N·m, leads to inconsistent wear levels among the friction pairs, resulting in inconsistent dimensions of the six bearing hole sizes in the V-type 10-cylinder diesel engine block components during the final stitching.

[0006] In existing diesel engine components, the inconsistent friction coefficients of the friction pairs formed between the main bearing studs, bearing caps, nuts, and supports during assembly result in inconsistent preload, which in turn leads to bearing hole deformation and affects engine lifespan. Summary of the Invention

[0007] The purpose of this invention is to provide a high-speed, high-power diesel engine block main bearing stud stretching tool and method to solve the problem mentioned above where inconsistent friction coefficients of the friction pairs formed between the main bearing stud, bearing cap, nut, and support lead to inconsistent preload, which in turn causes bearing hole deformation and affects engine service life.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] In a first aspect, the present invention provides a high-speed, high-power diesel engine block main bearing stud stretching tool, comprising:

[0010] A fixing component, comprising a base and clamping bolts, wherein clamping bolts are installed through both sides of the base, and the clamping bolts are used to fix the base to the mating surface of the machine body;

[0011] A support assembly is connected to the base. The support assembly is used to vertically limit the bearing cover. Multiple sets of main bearing studs are connected to the bearing cover. A clamping component is connected to the main bearing studs. The main bearing studs cooperate with the clamping component to fix the bearing cover to the mating surface of the machine body.

[0012] A stretching actuator assembly, one end of which is connected to the main bearing stud and the other end of which is connected to the base, is used to vertically stretch to a preset elongation amount to stretch multiple sets of main bearing studs.

[0013] A limiting component is provided on the stretching execution component, and a support component is provided through the middle of the limiting component. The limiting component is used to limit the stretching execution component.

[0014] The stretching actuator is used to stretch vertically to a preset elongation to stretch multiple sets of main bearing studs and to tighten the clamping component so that the multiple sets of main bearing studs maintain a uniform preload on the bearing cap.

[0015] As a further aspect of the present invention: a central screw hole is provided in the middle of the base, and multiple sets of symmetrical first stud holes and second stud holes are provided on both sides of the central screw hole. A support component is installed in the central screw hole, and a tensioning actuator is installed in the first stud hole and the second stud hole.

[0016] As a further embodiment of the present invention: the clamping component includes a first clamping nut and a support member; multiple sets of main bearing studs are symmetrically distributed on both sides of the bearing cover; the main bearing studs on the outer side of the bearing cover are sleeved with the support member and threaded with the first clamping nut; the main bearing studs on the inner side of the bearing cover are threaded with the first clamping nut; the main bearing studs cooperate with the first clamping nut to fix the bearing cover to the mating surface of the machine body.

[0017] As a further aspect of the present invention: the tensioning actuator includes a first double-ended stud, a second double-ended stud, and a tension nut, wherein the tension nut is threadedly connected to the main bearing stud, the first double-ended stud is installed in the first stud hole and threadedly connected to the tension nut, and the first double-ended stud and the inner main bearing stud are arranged on the same axis.

[0018] The second double-ended stud is installed in the second stud hole and threadedly connected to the tension nut; the first double-ended stud and the inner main bearing stud are arranged on the same axis.

[0019] The upper ends of the first and second double-ended studs are both fitted with thrust bearings and threaded with second clamping nuts, and the thrust bearings abut against the upper end face of the base.

[0020] Both the first and second double-ended studs have a limiting portion, and a limiting component is provided on the limiting portion of the first and second double-ended studs. The limiting component is used to limit the rotation of the first and second double-ended studs.

[0021] The synchronous knob pulls multiple sets of second clamping nuts to stretch the first and second double-ended studs to a preset elongation, thereby stretching multiple sets of main bearing studs and tightening the first clamping nut, so that multiple sets of main bearing studs maintain a uniform preload on the bearing cap.

[0022] As a further aspect of the present invention: a countersunk hole is provided on the upper end face of the base, and the thrust bearing is engaged in the countersunk hole.

[0023] As a further aspect of the present invention: the limiting component includes a limiting plate, the limiting plate having a central hole in the middle and limiting holes on both sides of the central hole, the limiting portions of the first double-ended stud and the second double-ended stud being matched and engaged in the limiting holes, and a support component being installed through the central hole.

[0024] As a further aspect of the present invention: the cross-section of the limiting part is an equilateral hexagon, and the limiting hole matches the limiting part.

[0025] As a further embodiment of the present invention: the support assembly includes a support bolt and a locking nut, the locking nut is threaded onto the support bolt, the support bolt is threaded into the central threaded hole, one end of the support bolt abuts against the upper end face of the bearing cover, the support bolt is used to vertically limit the displacement of the bearing cover, and the locking nut is used to lock the support bolt.

[0026] Secondly, the present invention provides a method for stretching the stud of the main bearing of a high-speed, high-power diesel engine block, the method comprising the following steps:

[0027] Fix the base to the mating surface of the machine body, and use the main bearing stud to engage with the clamping component to fix the bearing cover to the mating surface of the machine body;

[0028] The support assembly is mounted on the base; the support assembly is used to limit the vertical displacement of the bearing cover.

[0029] One end of the tension actuator is connected to the main bearing stud, and the other end is connected to the base. A limit component is set on the tension actuator.

[0030] The stretching actuator is used to vertically stretch to a preset elongation to stretch multiple sets of main bearing studs and tighten the clamping components so that the multiple sets of main bearing studs maintain a uniform preload on the bearing cap.

[0031] Release the tool and repeat the above steps to complete the tensioning and pre-tightening of all main bearing studs.

[0032] As a further aspect of the present invention, the preset elongation is 0.7mm–0.8mm.

[0033] Compared with the prior art, the beneficial effects of the present invention are:

[0034] 1. In this invention, by simultaneously tightening the second clamping nut on the outer second double-ended stud, the tension on the second double-ended stud is transmitted to the main bearing stud through the tension nut, thereby stretching the outer main bearing stud. When the outer second double-ended stud is simultaneously stretched to the preset elongation, the outer main bearing stud has the required preload. At this time, the first clamping nut on the outer main bearing stud is in a tightenable state. Rotating the first clamping nut to the upper contact surface of the support member can maintain the preload of the outer main bearing stud. Then, by simultaneously tightening the second clamping nut on the inner first double-ended stud through the actuator, and performing the same steps as above, the tension preload of the inner main bearing stud is completed. Rotating the first clamping nut on the inner main bearing stud to the upper contact surface of the bearing cover can maintain the preload of the outer main bearing stud. This allows multiple sets of main bearing studs on the inner and outer sides to maintain corresponding and consistent preloads, thereby maintaining the stability of the bearing hole and extending the service life of the engine.

[0035] 2. In this invention, the upper crankcase is fixedly connected to the base by a clamping bolt, and a support assembly and a tensioning execution assembly are installed on the base. One end of the support assembly is fixed to the base, that is, the support bolt is threaded through the central threaded hole. When the knob supports the bolt stably contacts the upper end face of the bearing cover at the bottom, the knob locks the nut to the upper end face of the base to lock the support bolt, so as to prevent the support bolt from loosening. The support bolt limits the vertical displacement of the bearing cover and prevents the bearing cover from moving vertically during the tensioning process of the main bearing stud. Attached Figure Description

[0036] Figure 1 This is a schematic cross-sectional view of the overall structure of the present invention;

[0037] Figure 2 For the present invention Figure 1 Enlarged structural diagram at point A in the middle;

[0038] Figure 3 This is a schematic diagram of the first and second double-ended studs of the present invention;

[0039] Figure 4 This is a schematic diagram of the limiting plate structure of the present invention;

[0040] Figure 5 This is a schematic diagram of the base structure of the present invention;

[0041] Figure 6 This is a schematic diagram of the method flow of the present invention.

[0042] In the diagram: 1. Support bolt; 2. Locking nut; 3. First double-ended stud; 31. Limiting part; 4. Second double-ended stud; 5. Clamping bolt; 6. Limiting plate; 61. Center hole; 62. Limiting hole; 7. Tension nut; 8. First clamping nut; 9. Main bearing stud; 10. Upper crankcase; 11. Base; 1101. Center threaded hole; 1102. First stud hole; 1103. First stud hole; 1104. Countersunk hole; 12. Support component; 13. Bearing cap; 14. Second clamping nut; 15. Thrust bearing. Detailed Implementation

[0043] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] Example:

[0045] Taking a V-type 10-cylinder diesel engine as an example, the engine block is the upper crankcase 10 of the diesel engine, and the engine block mating surface is the mating surface of the upper crankcase 10. Multiple main bearing studs 9 are threaded onto the upper crankcase 10. The bearing cover 13 is installed through the multiple main bearing studs 9. Since the multiple main bearing studs 9 are distributed relatively compactly, it is inconvenient to stretch the multiple main bearing studs 9 on the inner and outer sides at the same time. This is not conducive to eliminating the influence of the inconsistent friction coefficient between the friction pairs on the preload, which in turn leads to the deformation of the bearing hole and thus affects the service life of the engine.

[0046] Please see Figures 1-5 In this embodiment of the invention, a high-speed, high-power diesel engine block main bearing stud stretching tool includes:

[0047] The fixing component includes a base 11 and clamping bolts 5. The clamping bolts 5 are installed through both sides of the base 11 and are used to fix the base 11 to the mating surface of the machine body.

[0048] A support assembly is connected to the base 11 and is used to vertically limit the bearing cover 13. Multiple sets of main bearing studs 9 are connected to the bearing cover 13, and clamping components are connected to the main bearing studs 9. The main bearing studs 9, in conjunction with the clamping components, fix the bearing cover 13 to the machine body mating surface. The base 11 has a central threaded hole 1101 in the middle, and multiple sets of symmetrical first stud holes 1102 and second stud holes 1103 are provided on both sides of the central threaded hole 1101. The support assembly is installed in the central threaded hole 1101, and the tensioning actuator is installed in the first stud holes 1102 and second stud holes 1103. The support assembly is installed through the central threaded hole 1101 in the base 11 to ensure stable installation. The first stud holes 1102 and second stud holes 1103 on both sides facilitate the insertion and installation of the tensioning actuator, making subsequent tensioning operations convenient.

[0049] Furthermore, the support assembly includes a support bolt 1 and a lock nut 2. The lock nut 2 is threaded onto the support bolt 1. The support bolt 1 is threaded into the central threaded hole 1101. One end of the support bolt 1 abuts against the upper end face of the bearing cover 13. The support bolt 1 is used to vertically limit the displacement of the bearing cover 13. The lock nut 2 is used to lock the support bolt 1.

[0050] The tensioning actuator is connected at one end to the main bearing stud 9 and at the other end to the base 11. The tensioning actuator is used to vertically stretch to a preset elongation to stretch multiple sets of main bearing studs 9.

[0051] A limiting component is provided on the stretching actuator, and a support component is provided through the middle of the limiting component. The limiting component is used to limit the stretching actuator.

[0052] The tensioning actuator is used to vertically stretch the main bearing studs 9 to a preset elongation, thereby stretching the multiple sets of main bearing studs 9 and tightening the clamping components so that the multiple sets of main bearing studs 9 maintain a uniform preload on the bearing cap 13.

[0053] Specifically, the machine body is the upper crankcase 10, the machine body mating surface is the mating surface of the upper crankcase 10, multiple main bearing studs 9 are threadedly connected to the upper crankcase 10, bearing caps 13 are connected to the multiple main bearing studs 9, and the clamping components on the main bearing studs 9 make initial contact connection with the bearing caps 13.

[0054] The upper crankcase 10 is fixedly connected to the base 11 by the clamping bolt 5, and a support assembly and a tensioning assembly are installed on the base 11. One end of the support assembly is fixed to the base 11, that is, the support bolt 1 is threaded through the central threaded hole 1101. When the knob support bolt 1 is stably against the upper end face of the bearing cover 13 at the bottom, the knob lock nut 2 is turned to the upper end face of the base 11 to lock the support bolt 1, so as to prevent the support bolt 1 from loosening. The vertical displacement of the bearing cover 13 is limited by the support bolt 1, so as to prevent the bearing cover 13 from moving vertically during the tensioning process of the main bearing stud 9.

[0055] Furthermore, the preferred type of clamping bolt 5 is M12×1.5;

[0056] The tensioning actuator is connected to the base 11. The other end of the tensioning actuator is connected to multiple sets of compactly distributed main bearing studs 9. The actuator drives the tensioning actuator to stretch to a preset elongation, which in turn drives a symmetrical set of main bearing studs 9 to stretch to a preset preload. The corresponding clamping component is turned to maintain the preset tension of the set of main bearing studs 9. Then, the tensioning actuator stretches the remaining symmetrical sets of main bearing studs 9. The corresponding clamping component is turned to ensure that multiple sets of main bearing studs 9 maintain a consistent preload through direct tensioning, thereby maintaining the stability of the bearing holes and extending the service life of the engine. This tool avoids the inconsistent preload caused by the inconsistent friction coefficients of the friction pairs in the system when the multiple sets of main bearing studs 9 are preloaded at a preset angle using a torque tool.

[0057] During the stretching process, the tensioning actuator is limited by the limiting component to keep the tensioning actuator stable. The device has a compact overall structure and is suitable for assembly of diesel engine blocks in space-constrained environments. Furthermore, the tool is reusable, which effectively reduces the frequency of tool changes during assembly and improves work efficiency.

[0058] Preferred, such as Figure 1 and Figure 2 As shown, the clamping component includes a first clamping nut 8 and a support member 12. Multiple sets of main bearing studs 9 are symmetrically distributed on both sides of the bearing cover 13. The main bearing studs 9 on the outer side of the bearing cover 13 are sleeved with the support member 12 and threadedly connected to the first clamping nut 8. The main bearing studs 9 on the inner side of the bearing cover 13 are threadedly connected to the first clamping nut 8. The main bearing studs 9 cooperate with the first clamping nut 8 to fix the bearing cover 13 to the mating surface of the machine body.

[0059] Specifically, the bearing cover 13 is initially connected to the upper crankcase 10 by tightening the first clamping nut 8 threaded on the main bearing stud 9. Since multiple sets of main bearing studs 9 are densely distributed, in order to avoid mutual interference between the first clamping nuts 8 on the inner and outer main bearing studs 9 when tightening the knob, a support member 12 is sleeved on the outer main bearing stud 9, so that the first clamping nuts 8 on the inner and outer main bearing studs 9 are misaligned in vertical space, which facilitates the subsequent tightening of the first clamping nut 8.

[0060] Preferred, such as Figure 1 and Figure 3 As shown, the tensioning actuator includes a first double-ended stud 3, a second double-ended stud 4, and a tension nut 7. The tension nut 7 is threaded onto the main bearing stud 9. The first double-ended stud 3 is installed in the first stud hole 1102 and threaded onto the tension nut 7. The first double-ended stud 3 and the inner main bearing stud 9 are arranged on the same axis. The tension nut 7 is preferably a non-standard nut M14×1.5-5H.

[0061] The second double-ended stud 4 is installed in the second stud hole 1103 and threadedly connected to the tension nut 7. The first double-ended stud 3 and the inner main bearing stud 9 are set on the same axis.

[0062] The upper ends of the first double-ended stud 3 and the second double-ended stud 4 are both fitted with thrust bearings 15 and threaded with second clamping nuts 14. The thrust bearings 15 abut against the upper end face of the base 11.

[0063] Both the first double-ended stud 3 and the second double-ended stud 4 have a limiting part 31. A limiting component is provided on the limiting part 31 of the first double-ended stud 3 and the second double-ended stud 4. The limiting component is used to limit the rotation of the first double-ended stud 3 and the second double-ended stud 4.

[0064] The synchronous knob pulls multiple sets of second clamping nuts 14 to stretch the first double-ended stud 3 and the second double-ended stud 4 to a preset elongation, thereby stretching multiple sets of main bearing studs 9 and tightening the first clamping nut 8, so that the multiple sets of main bearing studs 9 maintain a uniform preload on the bearing cover 13.

[0065] Specifically, the tension nut 7 is connected to the upper ends of multiple sets of main bearing studs 9 on the inner and outer sides. The corresponding first double-ended studs 3 and second double-ended studs 4 are installed through the corresponding first stud holes 1102 and second stud holes 1103 on the base 11. Limiting components are placed on the first double-ended studs 3 and second double-ended studs 4 to lock the first double-ended studs 3 and second double-ended studs 4 and prevent them from rotating during the tensioning process. This allows the corresponding first double-ended studs 3 and second double-ended studs 4 to be threadedly connected to the upper end of the tension nut 7, so that the first double-ended studs 3 and second double-ended studs 4 are connected to the multiple sets of main bearing studs 9 on the same axis. Thrust bearings 15 are sleeved on the upper ends of the first double-ended studs 3 and second double-ended studs 4 and threadedly connected to the second clamping nut 14.

[0066] The actuator is a tightening machine or torque wrench, which simultaneously tightens the second clamping nut 14 on the outer second double-ended stud 4, allowing the tension on the second double-ended stud 4 to be transmitted to the main bearing stud 9 through the tension nut 7, thereby stretching the outer main bearing stud 9. When the outer second double-ended stud 4 is stretched to the preset elongation, the outer main bearing stud 9 has the required preload. At this time, the first clamping nut 8 on the outer main bearing stud 9 is in a tightenable state. Rotating the first clamping nut 8 to the upper contact surface of the support member 12 releases the torque on the second clamping nut 14, i.e. The preload of the outer main bearing stud 9 can be maintained, and then the second clamping nut 14 on the inner first double-ended stud 3 is tightened synchronously through the actuator. The same steps are performed to complete the tension preload of the inner main bearing stud 9. The first clamping nut 8 on the inner main bearing stud 9 is rotated to the upper contact surface of the bearing cover 13 to release the torque on the second clamping nut 14. This can maintain the preload of the outer main bearing stud 9, thereby ensuring that the multiple sets of main bearing studs 9 on the inner and outer sides maintain corresponding and consistent preloads, thus maintaining the stability of the bearing hole and extending the service life of the engine.

[0067] The inner first double-ended stud 3 and the outer second double-ended stud 4 are simultaneously stretched to a preset elongation, which is measured by a measuring device. The measuring device includes various tools such as vernier calipers, micrometers and laser rangefinders. These tools can accurately measure the elongation of the first double-ended stud 3 and the outer second double-ended stud 4 to ensure that the stretching process meets the preset requirements.

[0068] The second clamping nut 14 is preferably a clamping nut M14×1.5-5H.

[0069] Preferred, such as Figure 1 and Figure 5 As shown, a countersunk hole 1104 is provided on the upper end face of the base 11, and the thrust bearing 15 is snapped into the countersunk hole 1104. The thrust bearing 15 is preferably a GB / T307.3 thrust bearing.

[0070] Specifically, the thrust bearing 15 is positioned and installed through the countersunk hole 1104, ensuring stable installation of the thrust bearing 15. At the same time, when the second clamping nut 14 is turned, the thrust bearing 15 reduces the friction between the second clamping nut 14 and the base 11, thereby improving the efficiency and accuracy of the nut tightening process.

[0071] Preferred, such as Figure 1 and Figure 4 As shown, the limiting component includes a limiting plate 6, with a central hole 61 in the middle of the limiting plate 6 and limiting holes 62 on both sides of the central hole 61. The limiting parts 31 of the first double-ended stud 3 and the second double-ended stud 4 are matched and engaged in the limiting holes 62. The supporting component is installed through the central hole 61.

[0072] Specifically, the limiting plate 6, through its central hole 61, cooperates with the support component, allowing the support bolt 1 to pass through and be installed. At the same time, the limiting hole 62 can effectively limit the movement range of the first double-ended stud 3 and the second double-ended stud 4, ensuring that they maintain a precise positional relationship during the stretching process and reducing the problem of uneven preload caused by stud offset.

[0073] Preferred, such as Figure 3 As shown, the limiting part 31 has an equilateral hexagonal cross section, and the limiting hole 62 matches the limiting part 31.

[0074] Specifically, the equilateral hexagonal design of the limiting part 31 can effectively prevent the first double-ended stud 3 and the second double-ended stud 4 from rotating during use, thereby further improving the stability of the overall structure.

[0075] Please see Figure 6 This invention provides a method for stretching the main bearing stud of a high-speed, high-power diesel engine block, the method comprising the following steps:

[0076] S1: Fix the base 11 to the mating surface of the machine body, and use the main bearing stud 9 to cooperate with the clamping component to fix the bearing cover 13 to the mating surface of the machine body;

[0077] S2: Install the support assembly on the base 11. The support assembly is used to limit the vertical displacement bearing cover 13.

[0078] S3: Connect one end of the tension actuator to the main bearing stud 9 and the other end to the base 11, and set a limit component on the tension actuator;

[0079] S4: The tensioning actuator is used to vertically stretch to a preset elongation to stretch multiple sets of main bearing studs 9 and tighten the clamping components so that the multiple sets of main bearing studs 9 maintain a uniform preload on the bearing cap 13.

[0080] S5: Release the tool and repeat the above steps to complete the tensioning and pre-tightening of all main bearing studs 9.

[0081] Preferably, the preset elongation is 0.7mm–0.8mm.

[0082] Specifically, through experiments and practical applications, it has been verified that the preset elongation within this range can effectively prevent material fatigue or structural damage caused by excessive stretching while ensuring that the main bearing stud 9 reaches the ideal preload, thus ensuring the stability and consistency of the stretching process.

[0083] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A high-speed, high-power diesel engine block main bearing stud stretching tool, characterized in that, include: The fixing component includes a base (11) and clamping bolts (5), with clamping bolts (5) installed through both sides of the base (11), and the clamping bolts (5) are used to fix the base (11) to the mating surface of the machine body; A support assembly is connected to the base (11). The support assembly is used to vertically limit the bearing cover (13). Multiple sets of main bearing studs (9) are connected to the bearing cover (13). A clamping component is connected to the main bearing studs (9). The main bearing studs (9) cooperate with the clamping component to fix the bearing cover (13) to the machine body mating surface. A stretching actuator is provided, with one end connected to the main bearing stud (9) and the other end connected to the base (11). The stretching actuator is used to stretch vertically to a preset elongation amount to stretch multiple sets of main bearing studs (9). A limiting component is provided on the stretching execution component, and a support component is provided through the middle of the limiting component. The limiting component is used to limit the stretching execution component. The stretching actuator is used to stretch vertically to a preset elongation to stretch multiple sets of main bearing studs (9) and tighten the clamping component so that the multiple sets of main bearing studs (9) maintain a uniform preload on the bearing cap (13).

2. The high-speed, high-power diesel engine block main bearing stud stretching tool according to claim 1, characterized in that: The base (11) has a central screw hole (1101) in the middle, and multiple sets of symmetrical first stud holes (1102) and second stud holes (1103) are provided on both sides of the central screw hole (1101). A support component is installed in the central screw hole (1101), and a tensioning component is installed in the first stud hole (1102) and the second stud hole (1103).

3. The high-speed, high-power diesel engine block main bearing stud stretching tool according to claim 2, characterized in that: The clamping component includes a first clamping nut (8) and a support member (12). Multiple sets of main bearing studs (9) are symmetrically distributed on both sides of the bearing cover (13). The main bearing studs (9) on the outer side of the bearing cover (13) are fitted with the support member (12) and threaded with the first clamping nut (8). The main bearing studs (9) on the inner side of the bearing cover (13) are threaded with the first clamping nut (8). The main bearing studs (9) cooperate with the first clamping nut (8) to fix the bearing cover (13) to the machine body mating surface.

4. The high-speed, high-power diesel engine block main bearing stud stretching tool according to claim 3, characterized in that: The tensioning actuator includes a first double-ended stud (3), a second double-ended stud (4), and a tension nut (7). The tension nut (7) is threaded onto the main bearing stud (9). The first double-ended stud (3) is installed in the first stud hole (1102) and threaded onto the tension nut (7). The first double-ended stud (3) and the inner main bearing stud (9) are arranged on the same axis. The second double-ended stud (4) is installed in the second stud hole (1103) and threadedly connected to the tension nut (7). The first double-ended stud (3) and the inner main bearing stud (9) are set on the same axis. The upper ends of the first double-ended stud (3) and the second double-ended stud (4) are both fitted with thrust bearings (15) and threaded with second clamping nuts (14). The thrust bearings (15) abut against the upper surface of the base (11). The first double-ended stud (3) and the second double-ended stud (4) both have a limiting part (31). A limiting component is provided on the limiting part (31) of the first double-ended stud (3) and the second double-ended stud (4). The limiting component is used to limit the rotation of the first double-ended stud (3) and the second double-ended stud (4). The synchronous knob pulls multiple sets of second clamping nuts (14) to stretch the first double-ended stud (3) and the second double-ended stud (4) to a preset elongation, so as to stretch multiple sets of main bearing studs (9) and tighten the first clamping nut (8) so that multiple sets of main bearing studs (9) maintain a uniform preload on the bearing cap (13).

5. The high-speed, high-power diesel engine block main bearing stud stretching tool according to claim 4, characterized in that: The upper surface of the base (11) is provided with a countersunk hole (1104), and the thrust bearing (15) is engaged in the countersunk hole (1104).

6. The high-speed, high-power diesel engine block main bearing stud stretching tool according to claim 5, characterized in that: The limiting component includes a limiting plate (6), a central hole (61) is provided in the middle of the limiting plate (6), and limiting holes (62) are provided on both sides of the central hole (61). The limiting parts (31) of the first double-ended stud (3) and the second double-ended stud (4) are matched and engaged in the limiting holes (62). A support component is installed through the central hole (61).

7. A high-speed, high-power diesel engine block main bearing stud stretching tool according to claim 6, characterized in that: The limiting part (31) has an equilateral hexagonal cross section, and the limiting hole (62) matches the limiting part (31).

8. The high-speed, high-power diesel engine block main bearing stud stretching tool according to claim 7, characterized in that: The support assembly includes a support bolt (1) and a lock nut (2). The lock nut (2) is threaded onto the support bolt (1). The support bolt (1) is threaded into the central threaded hole (1101). One end of the support bolt (1) abuts against the upper end face of the bearing cover (13). The support bolt (1) is used to vertically limit the displacement of the bearing cover (13). The lock nut (2) is used to lock the support bolt (1).

9. A method for stretching the main bearing stud of a high-speed, high-power diesel engine block, applied to the high-speed, high-power diesel engine block main bearing stud stretching tool as described in any one of claims 1-8, characterized in that: The method includes the following steps: Fix the base (11) to the mating surface of the machine body, and use the main bearing stud (9) to cooperate with the clamping component to fix the bearing cover (13) to the mating surface of the machine body; The support assembly is installed on the base (11) and is used for the vertical displacement limiting bearing cover (13). One end of the tensioning actuator is connected to the main bearing stud (9), and the other end is connected to the base (11), and a limit component is set on the tensioning actuator; The stretching actuator is used to stretch vertically to a preset elongation to stretch multiple sets of main bearing studs (9) and tighten the clamping components so that the multiple sets of main bearing studs (9) maintain a uniform preload on the bearing cap (13); Release the tool and repeat the above steps to complete the tensioning and pre-tightening of all main bearing studs (9).

10. The method for stretching the main bearing stud of a high-speed, high-power diesel engine block according to claim 9, characterized in that: The preset elongation is 0.7mm–0.8mm.

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