A machining device and method for controlling deformation of a high-power high-rotation diesel engine crankshaft

Abstract

The application provides a machining device for controlling deformation of a high-power high-rotation-speed diesel engine crankshaft, which comprises a bolt and a screw sleeve; the screw sleeve comprises a shell, a containing section, a fixing section and a pre-tightening section, the containing section, the fixing section and the pre-tightening section are sequentially arranged inside the shell, the containing section is internally provided with a containing hole, the fixing section is threadedly connected with the bolt, the pre-tightening section is internally provided with a movable channel, the movable channel is internally provided with a movable nut, the movable nut is threadedly connected with the bolt, the movable nut is provided with a pre-tightening bolt, and the end of the pre-tightening bolt is in contact with the fixing section. The machining device is connected with the bolt through the fixing section, the two ends of the machining device can be tightly pressed against or loosened from the surfaces on the two sides by rotating the screw sleeve, and the machining device is suitable for machining crankshafts of various models; the movable nut can move towards or away from the fixing section, and can rotate with the shell simultaneously with the fixing section; and the end of the pre-tightening bolt can provide a pre-tightening force away from the fixing section, preventing the relative loosening between the screw sleeve and the bolt.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of diesel engine crankshaft manufacturing, in particular to a machining device and method for controlling deformation of a high-power high-speed diesel engine crankshaft. BACKGROUND

[0002] As a core component of a diesel engine, a crankshaft collects the power emitted by a cylinder block of the diesel engine, converts the power into torque to drive a load, and outputs effective power to the outside, and drives other auxiliary devices of the diesel engine. When the diesel engine is running, the crankshaft is constantly subjected to alternating stress from a connecting rod, and the shape of the crankshaft is complex, which causes serious stress concentration, and is prone to vibration, deformation or wear of the crankshaft, and even causes the diesel engine to malfunction or even damage.

[0003] During the machining of the crankshaft, controlling the deformation of the crankshaft is a key technology to ensure the performance of the crankshaft, especially when manufacturing a long and thin crankshaft with a large length-diameter ratio, it is particularly important to control the deformation of the crankshaft as much as possible to reduce the journal runout as much as possible, so as to ensure the normal operation of the diesel engine. SUMMARY

[0004] Therefore, the present application aims to provide a machining device and method for controlling deformation of a high-power high-speed diesel engine crankshaft to control the deformation degree of a long and thin crankshaft with a large length-diameter ratio during machining.

[0005] To achieve the above-mentioned purpose, the technical scheme of the present application is as follows:

[0006] In a first aspect, a machining device for controlling deformation of a high-power high-speed diesel engine crankshaft is provided, comprising a bolt and a nut.

[0007] The nut comprises an outer shell, a receiving section, a fixing section and a pre-tightening section, the receiving section, the fixing section and the pre-tightening section are arranged in the outer shell in sequence, a receiving hole for receiving an end of the bolt is arranged in the receiving section, the fixing section is threadedly connected with the bolt, a movable channel is arranged in the pre-tightening section, a movable nut is arranged in the movable channel, the movable nut is threadedly connected with the bolt, a pre-tightening bolt is further arranged on the movable nut, and an end of the pre-tightening bolt is in contact with the fixing section.

[0008] Further, the fixing section is a fixed nut, and the fixed nut is fixedly connected with an inner surface of the outer shell.

[0009] Further, a threaded hole for accommodating the pre-tightening bolt is arranged on the movable nut.

[0010] Further, anti-wear pads are arranged on the bolt and the nut, respectively, and the anti-wear pads are arranged on the end faces of the bolt and the nut away from each other.

[0011] Further, the inner surface of the accommodating hole is a smooth surface.

[0012] In a second aspect, a machining method for controlling deformation of a high-power high-rotation diesel engine crankshaft, uses the machining device for controlling deformation of a high-power high-rotation diesel engine crankshaft, and includes the following steps:

[0013] Step S1: machining both ends and a center hole of the crankshaft;

[0014] Step S2: rough milling of the main journal and the connecting rod journal and releasing stress;

[0015] Step S3: repairing the center hole;

[0016] Step S4: turning the main journal and the connecting rod journal, and turning the cone;

[0017] Step S5: machining a weight-reducing hole and releasing stress;

[0018] Step S6: rough grinding of the main journal and the connecting rod journal and releasing stress;

[0019] Step S7: semi-finish grinding of the main journal and the connecting rod journal;

[0020] Step S8: machining an oil hole and releasing stress;

[0021] Step S9: repairing the center hole;

[0022] Step S10: finish grinding of the main journal and the connecting rod journal, and finish grinding of the cone;

[0023] Step S11: nitriding treatment;

[0024] Step S12: polishing of the main journal and the connecting rod journal;

[0025] The nitriding treatment includes:

[0026] Step S11-1: connecting a hoisting member with the center main journal of the crankshaft, and hoisting the crankshaft;

[0027] Step S11-2: arranging the machining device between the crank arms on both sides of the center main journal, rotating the screw sleeve of the machining device, and abutting the two ends of the machining device against the surfaces of the crank arms on both sides of the center main journal;

[0028] Step S11-3: arranging the machining device at the main journal symmetrically on both sides of the center main journal, and arranging the machining device between the crank arms on both sides of the main journal, rotating the screw sleeve of the machining device, and abutting the two ends of the machining device against the surfaces of the crank arms on both sides of the main journal;

[0029] Step S11-4: rotating the pre-tightening bolts of all the machining devices, and pre-tightening and fixing the machining devices;

[0030] Step S11-5: nitriding heat treatment;

[0031] Step S11-6: reverse rotation of the machining device pre-tightening bolt, and then reverse rotation of the machining device sleeve, all the machining device is disassembled.

[0032] Further, the machining device is arranged below the center spindle neck and the spindle neck symmetrically on both sides of the center spindle neck.

[0033] Further, the wear pads at both ends of the machining device are respectively in contact with the opposite surfaces of the curved arms on both sides of the spindle neck.

[0034] Further, the stress relief is aging treatment.

[0035] Compared with the prior art, the machining device and method for controlling the deformation of the crankshaft of the high-power high-speed diesel engine have the following advantages:

[0036] (1) The machining device is connected by the fixed section inside the shell to the threaded connection of the sleeve and the bolt, and the length of the machining device can be adjusted by rotating the sleeve, so that the two ends of the machining device can be tightly or loosely contacted with the surfaces on both sides, and the machining device can be applied to machining of various types of crankshafts. The movable nut inside the shell can move towards or away from the fixed section in the axial direction of the accommodating hole in the movable channel, and the movable nut can rotate with the shell at the same time. The end of the pre-tightening bolt on the movable nut can be in contact with the fixed section to provide a pre-tightening force away from the fixed section. When the movable nut and the fixed section are simultaneously connected with the bolt, the relative loosening between the sleeve and the bolt is prevented.

[0037] (2) The wear pads arranged at both ends of the bolt and the sleeve of the machining device can prevent the sleeve from causing wear to the surface of the crankshaft during the process of being screwed and abutting, which can cause the crankshaft machining to not meet the relevant requirements. The smooth inner surface of the accommodating hole does not hinder the axial movement of the bolt under the guidance of the lead screw, so that the machining device can be smoothly installed.

[0038] (3) The machining method of the application controls the deformation of the crankshaft of the high-power high-speed diesel engine by using the machining device to hoist the crankshaft from the center main journal close to the center of gravity, and setting the machining device below the center main journal and below the main journals symmetrically on both sides of the center main journal, and by using the machining device to press against the crank arms on both sides of the main journal, the two ends of the crankshaft are bent and deformed upwards before the crankshaft is subjected to nitriding heat treatment, so as to offset the downward bending deformation of the two ends of the crankshaft caused by gravity during the nitriding heat treatment, and the pre-tightening bolt can keep the stability of the machining device pressing against the crank arm, avoiding uncontrollable deformation of the crankshaft caused by loosening of the machining device, and after the nitriding heat treatment is completed, all the machining devices are disassembled, and the crankshaft can restore to the shape before the reverse deformation, so as to ensure that the journal runout of the crankshaft is within the range required by the relevant requirements.

[0039] (4) The machining method of the application controls the deformation of the crankshaft of the high-power high-speed diesel engine by using the machining device to hoist the crankshaft from the center main journal close to the center of gravity, and setting the machining device below the center main journal and below the main journals symmetrically on both sides of the center main journal, and by using the machining device to press against the crank arms on both sides of the main journal, the two ends of the crankshaft are bent and deformed upwards before the crankshaft is subjected to nitriding heat treatment, so as to offset the downward bending deformation of the two ends of the crankshaft caused by gravity during the nitriding heat treatment, and the pre-tightening bolt can keep the stability of the machining device pressing against the crank arm, avoiding uncontrollable deformation of the crankshaft caused by loosening of the machining device, and after the nitriding heat treatment is completed, all the machining devices are disassembled, and the crankshaft can restore to the shape before the reverse deformation, so as to ensure that the journal runout of the crankshaft is within the range required by the relevant requirements. BRIEF DESCRIPTION OF DRAWINGS

[0040] The accompanying drawings, which form a part of the present application, are used to provide a further understanding of the application and are incorporated herein in their entirety. The illustrative embodiments of the present application, together with its description, serve to explain the application. In the drawings:

[0041] Figure 1 A structure schematic view of a machining device for controlling the deformation of a crankshaft of a high-power high-speed diesel engine according to the first embodiment of the application;

[0042] Figure 2 A sectional view schematic view of a sleeve according to the first embodiment of the application;

[0043] Figure 3 A flow chart of a machining method for controlling the deformation of a crankshaft of a high-power high-speed diesel engine according to the second embodiment of the application;

[0044] Figure 4 A flow chart of a nitriding treatment according to the second embodiment of the application;

[0045] Figure 5 A structure schematic view of a crankshaft according to the second embodiment of the application.

[0046] BRIEF DESCRIPTION OF DRAWINGS

[0047] 1 - first wear pad; 2 - bolt; 3 - screw; 4 - screw sleeve; 5 - second wear pad; 6 - movable nut; 7 - pre-tightening bolt; 8 - fixed nut; 9 - accommodating hole; 10 - movable threaded hole; 11 - movable passage; 12 - housing; 13 - fixed threaded hole; 14 - accommodating section; 15 - center spindle journal. DETAILED DESCRIPTION

[0048] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0049] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second" and the like are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined with "first", "second" and the like can explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0050] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood through specific circumstances.

[0051] The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0052] Embodiment one

[0053] Figure 1 A structure diagram of a processing device for controlling the deformation of a high-power high-speed diesel engine crankshaft according to the first embodiment of the present application. A processing device for controlling the deformation of a high-power high-speed diesel engine crankshaft, as shown in Figure 1 It includes a bolt 2 and a screw sleeve 4;

[0054] Figure 2 A cross-sectional view of the screw sleeve according to the first embodiment of the present application. As shown in Figure 2As shown, the sleeve comprises an outer shell 12, a receiving section 14, a fixing section and a pre-tightening section, the receiving section, the fixing section and the pre-tightening section are sequentially arranged inside the outer shell, the receiving section is provided with a receiving hole 9 for receiving the end of the bolt, the fixing section is threadedly connected with the bolt, the pre-tightening section is provided with a movable channel 11, the movable channel is provided with a movable nut 6, the movable nut is threadedly connected with the bolt, and the movable nut is further provided with a pre-tightening bolt 7, the end of the pre-tightening bolt is in contact with the fixing section.

[0055] One end of the outer shell is provided with an opening, the shank 3 of the bolt can extend into the interior of the outer shell from the opening, the receiving section, the fixing section and the pre-tightening section are sequentially arranged towards the opening inside the outer shell, the end of the bolt extending into the outer shell is inserted into the receiving hole, the diameter of the receiving hole is slightly larger than the diameter of the shank, the receiving hole can prevent the axial direction of the bolt from being deflected when the bolt is rotated, but will not hinder the axial movement of the bolt. Exemplarily, the inner surface of the receiving hole is a smooth surface.

[0056] The fixing section is provided with a threaded hole through which the shank can pass, the center of the threaded hole is located on the axis of the receiving hole, the bolt can be threadedly connected with the threaded hole, so that the bolt can move towards or away from the sleeve when the bolt is rotated. An alternative embodiment of the present embodiment is that the fixing section is a fixing nut 8, and the fixing nut is fixedly connected with the inner surface of the outer shell. The center of the fixing threaded hole 13 of the fixing nut is located on the axis of the receiving hole, and the bolt is connected with the fixing nut through the fixing threaded hole, so that the bolt can move towards or away from the sleeve when the bolt is rotated.

[0057] The movable channel of the pre-tightening section is arranged between the opening of the outer shell and the fixing section, the movable channel is provided with a hexagonal guide rail which can cooperate with the shape of the movable nut, and the movable nut can move towards or away from the fixing section along the hexagonal guide rail. The center of the movable threaded hole 10 of the movable nut is located on the axis of the receiving hole, and the movable nut is connected with the bolt through the movable threaded hole. The hexagonal guide rail can make the center of the movable nut coincide with the axis of the receiving hole when the movable nut moves, and the axial direction of the movable nut will not be deflected when the movable nut moves. The movable nut can rotate with the outer shell under the limitation of the hexagonal guide rail, and the movable nut and the fixing section can be threadedly connected with the bolt at the same time.

[0058] The axial direction of the pre-tightening bolt is parallel to the axial direction of the receiving hole, the pre-tightening bolt extends from the opening of the outer shell, passes through the movable nut and extends towards the fixing section, and a pre-tightening force in the direction away from the fixing section can be provided to the movable nut by rotating the pre-tightening bolt. Exemplarily, the movable nut is provided with a threaded hole for receiving the pre-tightening bolt, the pre-tightening bolt passes through the threaded hole, the head of the pre-tightening bolt extends out of the opening of the outer shell, and the end of the pre-tightening bolt extends towards the fixing section and is in contact with the fixing section.

[0059] When the sleeve is screwed on the bolt, the fixed section and the movable nut rotate simultaneously with the shell and are screwed with the bolt at the same time, at this time the distance between the movable nut and the fixed section will be limited, the pre-tightening bolt can be rotated to move the pre-tightening bolt to the fixed section, and the end of the pre-tightening bolt is tightly pressed against the fixed section, so that the movable nut and the fixed section generate a mutual moving away force, i.e. a pre-tightening force, which can greatly avoid the possibility of loosening of the sleeve after being screwed with the bolt, and the relative fixation between the sleeve and the bolt is more reliable.

[0060] Optionally, in order to prevent the bolt and the sleeve from causing wear to the surface of the crankshaft when the bolt and the sleeve contact the surface of the crankshaft, especially when the bolt and the sleeve continue to rotate and tightly contact the surface of the crankshaft after contacting the surface of the crankshaft, the bolt and the sleeve are provided with wear-resistant pads, the wear-resistant pads are arranged on the end faces of the bolt and the sleeve away from each other, the end of the bolt away from the sleeve is provided with a first wear-resistant pad 1, the end of the sleeve away from the bolt is provided with a second wear-resistant pad 5, and the two ends of the bolt and the sleeve away from each other are in contact with the crankshaft through the first wear-resistant pad and the second wear-resistant pad respectively, so that damage to the surface of the crankshaft is avoided.

[0061] In order to facilitate the operation of the shell, a convex rib with a hexagonal cross section can be arranged on the outer surface of the shell, so that the shape of the outer surface of the shell is close to the hexagonal shape of the outer part of the nut, and the sleeve can be easily tightened by using a tool for operating the nut.

[0062] Embodiment two

[0063] Figure 3 A flowchart of a processing method for controlling deformation of a high-power high-rotation-speed diesel engine crankshaft according to the embodiment two of the present application is shown. The processing method for controlling deformation of a high-power high-rotation-speed diesel engine crankshaft, as shown in the figure, utilizes the processing device for controlling deformation of a high-power high-rotation-speed diesel engine crankshaft, and includes the following steps: Figure 3

[0064] Step S1: processing the two ends and the center hole of the crankshaft;

[0065] Step S2: rough milling of the main shaft neck and the connecting rod neck and releasing stress;

[0066] Step S3: center hole finishing;

[0067] Step S4: turning of the main shaft neck and the connecting rod neck and the cone;

[0068] Step S5: processing of the weight-reducing hole and releasing stress;

[0069] Step S6: rough grinding of the main shaft neck and the connecting rod neck and releasing stress;

[0070] Step S7: semi-finish grinding of the main shaft neck and the connecting rod neck; ​

[0071] Step S8: machining oil hole and releasing stress;

[0072] Step S9: center hole finishing;

[0073] Step S10: fine grinding of main journal and connecting rod journal, fine grinding of cone;

[0074] Step S11: nitriding treatment;

[0075] Step S12: polishing of main journal and connecting rod journal;

[0076] In order to reduce the cutting process in the manufacturing process of the crankshaft, the precision forging is used as the blank of the crankshaft machining, and the outer shape of the crank arm is directly precision forged, so that the crank arm and the crank are no longer machined, and the generation of cutting stress is greatly reduced. First, the two ends of the crankshaft are machined to determine the center hole of the crankshaft machining, then the main journal and the connecting rod journal are coarsely milled, and the cutting stress generated by the coarse milling is released. In order to ensure the accuracy of the crankshaft machining, the center hole needs to be ground after coarse milling to ensure the accuracy of the center hole positioning, then the main journal and the connecting rod journal are turned, and the crank cone is turned, then the weight reduction hole is machined to reduce the weight of the connecting rod journal and reduce the centrifugal force generated when the crankshaft rotates, and then the stress is released. Then the main journal and the connecting rod journal are coarsely ground, and the stress is released again after coarse grinding, then the main journal and the connecting rod journal are coarsely ground again, and then the oil hole is machined, and then the cutting stress is released. After releasing the stress, the center hole is ground again to ensure the accuracy of the crankshaft machining, then the main journal and the connecting rod journal are finely ground, and the crank cone is finely ground. At this point, the cutting process involved in the crankshaft machining process is basically completed, and the crankshaft needs to be nitrided to strengthen the strength of the crankshaft, and the main journal and the connecting rod journal are polished after nitriding. In order to improve the service life of the crankshaft, the cutting stress in the machining process of the crankshaft should be fully released as much as possible. For example, the stress release is aging treatment, by adding one time aging treatment after machining the weight reduction hole in step S5 and adding one time aging treatment after coarse grinding in step S6 based on the original machining process, the cutting stress of turning and coarse grinding can be fully released, and the uneven stress is avoided to affect the normal work and service life of the crankshaft. In order to reduce the cutting amount during fine machining, a semi-fine grinding process of the main journal and the connecting rod journal is added based on the original process in step S7, and correspondingly, the machining allowance of fine grinding in step S10 is reduced from 0.75mm to 0.3mm, which greatly reduces the deformation caused by grinding heat and controls the cutting stress to a small degree.

[0077] Figure 4 The flowchart of the nitriding treatment according to the second embodiment of the present application is shown. Figure 4 The nitriding treatment includes:

[0078] Step S11-1: connecting the lifting member with the center main journal 15 of the crankshaft, lifting the crankshaft, as shown in Figure 5

[0079] Step S11-2: setting the machining device between the crank arms on both sides of the center main journal, rotating the screw sleeve 4 of the machining device, and abutting the two ends of the machining device against the surfaces of the crank arms on both sides of the center main journal.

[0080] Step S11-3: setting the machining device at the main journals symmetrically on both sides of the center main journal, and setting the machining device between the crank arms on both sides of the main journal, rotating the screw sleeve of the machining device, and abutting the two ends of the machining device against the surfaces of the crank arms on both sides of the main journal.

[0081] Step S11-4: rotating the pre-tightening bolts of all the machining devices, and pre-tightening and fixing the machining devices.

[0082] Step S11-5: nitriding heat treatment.

[0083] Step S11-6: rotating the pre-tightening bolts of the machining devices in reverse, then rotating the screw sleeves of the machining devices in reverse, and dismounting all the machining devices.

[0084] In the nitriding treatment, the machining device for controlling deformation of a high-power high-rotation diesel engine crankshaft according to Embodiment 1 is needed. In the lifting, in order to make the deformation of the crankshaft in the nitriding treatment uniform, the lifting position should be as close to the center of gravity of the crankshaft as possible, so the lifting member can be connected with the center main journal at the center of the crankshaft, and the crankshaft is lifted from the center of the main journal for nitriding treatment.

[0085] In the process of the nitriding heat treatment, the crankshaft will be bent and deformed due to gravity, so before the nitriding heat treatment, according to the deformation law and deformation amount of the crankshaft after nitriding, the machining device according to Embodiment 1 is used to reversely deform the crankshaft, so as to offset the deformation of the crankshaft in the process of the nitriding heat treatment. In this embodiment, the crankshaft is lifted at the center main journal of the crankshaft, and after the nitriding heat treatment, the two ends of the crankshaft will be bent and deformed downward due to gravity, so the crankshaft needs to be reversely bent and deformed upward before the nitriding heat treatment, so as to offset the deformation of the two ends of the crankshaft downward in the process of the nitriding heat treatment. After the nitriding heat treatment, the machining device is dismounted, so that the crankshaft can basically return to the state before the reverse deformation, and the journal runout of the crankshaft can be controlled within the range required by the relevant requirements. In this embodiment, the journal runout of the crankshaft before the nitriding heat treatment is 0.03 mm, and the journal runout of the crankshaft after the nitriding heat treatment can be controlled within 0.05 mm, which meets the requirements of the crankshaft product of this type. ​

[0086] In the installation of the processing device, the two ends of the processing device, i.e. the bolt head and the threaded sleeve far away from the bolt head, are respectively directed towards the curved arms on both sides of the center main shaft neck, the threaded sleeve is rotated to make the two ends of the processing device respectively abut against the surface of the curved arms, and the curved arms at both ends are bent and deformed upward by abutting against the curved arms. Next, the processing device is arranged at the main shaft neck at the symmetrical position on both sides of the center main shaft neck, and the processing device is also arranged between the curved arms on both sides of the main shaft neck, the threaded sleeve is rotated to make the two ends of the processing device respectively abut against the curved arms on both sides of the main shaft neck. Since the deformation amount of the curved arms is smaller as they are closer to both ends, the upward bending deformation degree of the curved arms abutted against by the processing device close to both ends of the curved arms also needs to be controlled to be correspondingly reduced.

[0087] After all the processing devices are installed, the pre-tightening bolts on the processing devices are rotated to generate a pre-tightening force between the movable nuts and the fixed parts of the processing devices, so as to prevent the loosening of the processing devices from causing uncontrolled deformation of the curved arms. After the nitriding heat treatment is completed, the pre-tightening bolts are rotated to release the pre-tightening force between the movable nuts and the fixed parts, the threaded sleeves are then rotated to loosen the processing devices, and all the processing devices are removed. At this time, the nitriding heat treatment of the curved arms is completed, and the deformation degree of the curved arms is controlled within the range required by the relevant requirements under the action of the processing devices.

[0088] Since the deformation of the curved arms is caused by the influence of gravity, the processing devices are arranged below the center main shaft neck and the main shaft necks symmetrically arranged on both sides of the center main shaft neck, so as to bend and deform the curved arms upward to offset the downward bending deformation of the curved arms caused by the influence of gravity during the nitriding heat treatment.

[0089] An optional embodiment of the present embodiment is that the wear-resistant pads at both ends of the processing device respectively abut against the opposite surfaces of the curved arms on both sides of the main shaft neck, and the two ends of the processing device abut against the surfaces of the curved arms through the wear-resistant pads. Since the wear-resistant pads exist, the curved arms will not be damaged in the process of rotating and abutting against the curved arms by the processing device.

[0090] The above only describes the preferred embodiments of the present application and is not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A processing device for controlling deformation of a high-power and high-speed diesel engine crankshaft, characterized in that: Comprising a bolt (2) and a threaded sleeve (4); The screw sleeve (4) comprises: a shell (12), a receiving section (14), a fixing section and a pre-tightening section, wherein the receiving section (14), the fixing section and the pre-tightening section are sequentially arranged inside the shell (12), a receiving hole (9) for accommodating the end of the bolt (2) is provided in the receiving section (14), the fixing section is threadedly connected to the bolt (2), a movable channel (11) is provided in the pre-tightening section, a movable nut (6) is provided in the movable channel (11), the movable nut (6) is threadedly connected to the bolt (2), a pre-tightening bolt (7) is further provided on the movable nut (6), and the end of the pre-tightening bolt (7) contacts the fixed section; The fixing section is a fixing nut (8), and the fixing nut (8) is fixedly connected to the inner surface of the outer shell (12); The movable nut (6) is provided with a threaded hole for accommodating a pre-tightening bolt (7); Anti-wear pads are provided on both the bolt (2) and the screw sleeve (4), and the anti-wear pads are respectively arranged on end surfaces of the bolt (2) and the screw sleeve (4) that are away from each other.

2. The processing device for controlling deformation of a high-power, high-speed diesel engine crankshaft according to claim 1, characterized in that: The inner surface of the accommodating hole (9) is a smooth surface.

3. A method for controlling deformation of a high-power, high-speed diesel engine crankshaft, using the device for controlling deformation of a high-power, high-speed diesel engine crankshaft according to any one of claims 1 to 2, characterized in that: The following steps are involved: Step S1: Processing the two ends and the center hole of the crankshaft; Step S2: Rough milling of the main journal and connecting rod journal and stress relief; Step S3: repairing the center hole; Step S4: turning the main journal and connecting rod journal, and turning the cone; Step S5: machining the lightening holes and relieving the stress; Step S6: Roughly grinding the main journal and connecting rod journal and relieving stress; Step S7: semi-finishing the main journal and connecting rod journal; Step S8: machining the oil hole and releasing the stress; Step S9: repairing the center hole; Step S10: fine grinding the main journal and connecting rod journal, and fine grinding the cone; Step S11: nitriding treatment; Step S12: polishing the main journal and connecting rod journal; The nitriding treatment comprises: Step S11-1: Connect the hanging piece to the central main journal (15) of the crankshaft and hang the crankshaft; Step S11-2: arranging the processing device between the crank arms on both sides of the central main shaft neck (15), rotating the screw sleeve (4) of the processing device, and pressing the two ends of the processing device against the crank arm surfaces on both sides of the central main shaft neck (15); Step S11-3: The processing devices are respectively arranged at the main journals symmetrically on both sides of the central main journal (15), and the processing devices are both arranged between the crank arms on both sides of the main journal, and the screw sleeves (4) of the processing devices are rotated to press the two ends of the processing devices against the crank arm surfaces on both sides of the main journal; Step S11-4: rotating the pre-tightening bolts (7) of all the processing devices to pre-tighten and fix the processing devices; Step S11-5: nitriding heat treatment; Step S11-6: reversely rotate the pre-tightening bolt (7) of the processing device, then reversely rotate the threaded sleeve (4) of the processing device, and disassemble all the processing devices.

4. A method for controlling deformation of a high-power, high-speed diesel engine crankshaft according to claim 3, characterized in that: The processing devices are both arranged below the central main shaft neck (15) and the main shaft necks symmetrical on both sides of the central main shaft neck (15).

5. The method for controlling deformation of a high-power, high-speed diesel engine crankshaft according to claim 3, characterized in that: The anti-wear pads at both ends of the processing device are respectively pressed tightly against the relative surfaces of the crank arms on both sides of the main shaft neck.

6. The method for controlling deformation of a high-power, high-speed diesel engine crankshaft according to claim 3, characterized in that: The stress release is an aging treatment.

Images