A surface treatment process and system for a cylinder block of a marine main engine and a marine engine

Abstract

The application provides a ship main engine cylinder body surface treatment process and system and a marine engine, and relates to the field of marine engine manufacturing. The application is aimed at the problem that the segmented cylinder body of a large marine engine is not convenient to implement overturning processing, which easily causes the center of gravity to deviate and collision damage. The application first folds all the cylinder bodies into a whole for rack end processing, reduces the local accumulated error caused by the thickness change of the sealing glue, then splits the whole cylinder body into multiple groups of combined cylinder bodies for separate overturning, so as to adapt to the lifting equipment capacity of the existing workshop. When splitting, the function cylinder body with a larger weight difference is arranged at the center position of the combined cylinder body, which balances the weight distribution on both sides of the special combined section, reduces the center of gravity deviation amplitude, and provides protection for the posture stability control in the turning process. While ensuring the overall machining precision of the segmented main engine cylinder body surface, the safety and engineering feasibility of the overall construction process are improved.

Description

Technical Field

[0001] This invention relates to the field of marine engine manufacturing, specifically to a surface treatment process and system for marine main engine cylinder blocks and a marine engine. Background Technology

[0002] For the segmented main engine cylinder block of large marine engines, gantry milling equipment is used for surface machining. In large-bore dual-fuel marine low-speed engines, the main engine has up to 10 segmented cylinder blocks, including 9 effective cylinder blocks and 1 functional cylinder block. The functional cylinder block is located between the effective cylinder blocks, and the number of effective cylinder blocks on both sides of the functional cylinder block is not equal. Thus, the position of the functional cylinder block corresponds to the cylinder head assembly above and the frame below, meeting the layout requirements of the functional components.

[0003] A certain thickness of sealant needs to be added between the connecting surfaces of adjacent cylinder segments. If the cylinder segments are surface-treated separately, the thickness deviation of the sealant after connection can easily cause excessive errors in the bottom surfaces of adjacent cylinder segments. If the cylinder segments are processed after being assembled as a whole, the total weight after assembly is about 200T, which exceeds the load-bearing capacity of the existing tilting equipment in the workshop, making it impossible to tilt the cylinder segments as a whole. The weight of the functional cylinder segment is different from that of the effective cylinder segment. If the segments are tilted, the combined segment with the effective cylinder segment is prone to a shift in the center of gravity, making it difficult to control the posture during tilting and inducing collision damage. Summary of the Invention

[0004] In view of this, the present invention provides a surface treatment process, system and marine engine for the main engine cylinder block, which, while ensuring the overall machining accuracy of the segmented main engine cylinder block surface, effectively reduces the risk of instability and collision during hoisting and turning operations, and improves the safety and engineering feasibility of the overall construction process.

[0005] The first objective of this invention is to provide a surface treatment process for marine main engine cylinder blocks, employing the following solution: include: All the segmented cylinder blocks are connected in sequence to form an integral cylinder block. The cylinder head end of the integral cylinder block faces down, and the frame end of the integral cylinder block faces up. The frame end of the integral cylinder block is machined. The overall cylinder block is divided into multiple sets of combined cylinder blocks. Each combined cylinder block includes at least two connected segmented cylinder blocks, and the functional cylinder block is located at the center of its combined cylinder block. Each cylinder block is flipped so that the cylinder head is facing upwards, and all cylinder blocks are reconnected to form a single cylinder block. The cylinder head and the circumferential sides of the single cylinder block are then machined.

[0006] Furthermore, the segmented cylinder blocks are arranged in sequence before connection, with the cylinder head end facing down and the frame end facing up, and the bottom is raised to leave space for flipping operations.

[0007] Furthermore, before connecting the segmented cylinder blocks, adhesive is applied to the connecting surfaces, and locating pins and fasteners are installed.

[0008] Furthermore, the segmented cylinder block includes an effective cylinder block and a functional cylinder block, with the same number of effective cylinder blocks connected to both sides of the functional cylinder block.

[0009] Furthermore, before using the lifting equipment to flip the combined cylinder body, the entire cylinder body is divided according to the lifting capacity of the lifting equipment, so that the weight of each group of combined cylinder bodies after division is less than or equal to the maximum lifting capacity of the lifting equipment.

[0010] Furthermore, the lifting equipment has a hook with a flexible cable that passes through the cylinder holes vertically distributed in the segmented cylinder body, and the combined cylinder body is flipped in stages.

[0011] Furthermore, after flipping the combined cylinder body, the position of the combined cylinder body is adjusted and the combined cylinder body is controlled to rotate half a turn, so that the protrusion on one side of the cylinder head end of the combined cylinder body is located in a clearance position away from the operating space, thus avoiding the equipment in the operating space.

[0012] Furthermore, when reconnecting adjacent sets of combined cylinders, the combined cylinders are adjusted to control the flatness of the frame end of the adjacent combined cylinders within a set range.

[0013] The second objective of this invention is to provide a segmented cylinder machining system for marine engines, used to perform the surface treatment process of the marine main engine cylinder block as described in the first objective. The system includes a tilting assembly, a gantry milling machine, and multiple leveling supports. The multiple leveling supports are used to support the segmented cylinder block. The tilting assembly is connected to the combined cylinder block to drive the combined cylinder block to adjust its posture. The gantry milling machine is mounted above the segmented cylinder block, and the milling head of the gantry milling machine can be adjusted to be above and to the side of the segmented cylinder block.

[0014] A third objective of the present invention is to provide a marine engine in which the cylinders of the marine engine are manufactured using the surface treatment process for marine main engine cylinder blocks as described in the first objective.

[0015] Compared with the prior art, the advantages and positive effects of this invention are: To address the issue of the difficulty in flipping and machining segmented cylinder blocks of large marine engines, which can easily lead to center of gravity shift and collision damage, this invention first assembles all cylinder blocks into a whole for frame-end machining, reducing local cumulative errors caused by variations in sealant thickness. Then, the entire cylinder block is disassembled into multiple sets of combined cylinder blocks for individual flipping, adapting to the lifting capacity of existing workshops. During disassembly, functional cylinder blocks with significant weight differences are strategically positioned at the center of their respective combined cylinder blocks, balancing the weight distribution on both sides of the special combined section and reducing the magnitude of center of gravity shift, thus ensuring stable attitude control during the flipping process. After each combined section is flipped, they are connected to form the entire cylinder block, completing the overall machining of the remaining surfaces. This resolves the contradiction between the high-precision machining requirements of large marine engine cylinder blocks and the limited flipping capacity of the workshop. While ensuring the overall machining accuracy of the segmented engine cylinder block surface, it effectively reduces the risk of instability and collision during lifting and flipping operations, improving the safety and engineering feasibility of the overall construction process. Attached Figure Description

[0016] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0017] Figure 1 This is a schematic diagram of the arrangement of the segmented cylinder blocks before connection in one or more embodiments of the present invention.

[0018] Figure 2 This is a schematic diagram of a segmented cylinder block connected to form an integral cylinder block in one or more embodiments of the present invention.

[0019] Figure 3 This is a schematic diagram illustrating the process of splitting a single cylinder block into multiple sets of combined cylinder blocks in one or more embodiments of the present invention.

[0020] Figure 4 This is a schematic diagram of the combined cylinder after being flipped in one or more embodiments of the present invention.

[0021] Figure 5 This is a schematic diagram of the reconnection of combined cylinder blocks to form an integral cylinder block in one or more embodiments of the present invention.

[0022] In the diagram, 1. Segmented cylinder block; 2. Functional cylinder block; 3. Integral cylinder block; 4. Frame end; 5. Cylinder head end; 6. Cylinder bore; 7. Effective cylinder block; 8. Connecting surface; 9. Combined cylinder block; 10. Protrusion. Detailed Implementation

[0023] Example 1 In a typical embodiment of the present invention, such as Figure 1 - Figure 5 As shown, a surface treatment process for the cylinder block of a marine main engine is presented.

[0024] The segmented main engine cylinder block of a large marine engine undergoes surface machining. The top of the cylinder block connecting to the cylinder head, the bottom of the connecting frame, and the axial sides are milled to ensure that the overall dimensions and surface roughness meet assembly requirements. However, machining the top and bottom ends requires flipping the main engine cylinder block to position the top and bottom ends for easy machining. If each segmented cylinder block 1 is machined individually, the flipping difficulty can be reduced, but independent machining can easily lead to excessive errors in the top, bottom, and sides after connection and assembly, resulting in insufficient overall flatness after assembly. If the entire cylinder block is machined to ensure flatness, the weight of the entire cylinder block far exceeds the load-bearing capacity of traditional flipping equipment. It is also necessary to consider the center of gravity distribution when the functional cylinder block 2 and the effective cylinder block 7 are flipped together, as a shift in the center of gravity can easily induce collision damage. Based on this, this embodiment provides a surface treatment process for the main engine cylinder block of a ship. After being assembled, the overall processing ensures that the error is within the allowable range. The cylinder block is then split into multiple sets of combined cylinder blocks 9 and flipped separately. The combined cylinder blocks 9 with functional cylinder blocks 2 are specially allocated to make their center of gravity distribution reasonable. After being reassembled, the remaining surfaces are processed to achieve the required processing accuracy and reduce the difficulty of flipping.

[0025] like Figures 1-5 As shown, the surface treatment process for the marine main engine cylinder block includes: All the segmented cylinder blocks 1 are connected in sequence to form an integral cylinder block 3. The cylinder head end 5 of the integral cylinder block 3, which is close to the cylinder head, faces downward and the frame end 4, which is close to the machine frame, faces upward. The frame end 4 of the integral cylinder block 3 is machined. The overall cylinder block 3 is divided into multiple sets of combined cylinder blocks 9. Each combined cylinder block 9 includes at least two connected segmented cylinder blocks 1, and the functional cylinder block 2 is located at the center of its combined cylinder block 9. Each of the combined cylinder blocks 9 is flipped so that the cylinder head end 5 faces upward, and all the combined cylinder blocks 9 are reconnected to form an integral cylinder block 3. The circumferential sides of the cylinder head end 5 and the integral cylinder block 3 are then machined.

[0026] Specifically, in the manufacturing of large dual-fuel low-speed marine engines, the overall length of the segmented main engine, comprising nine effective cylinder blocks 7 and one functional cylinder block 2, is relatively long. A certain thickness of sealant is applied between adjacent cylinder block segments 1. If each cylinder block segment 1 is machined separately on a machine tool, unavoidable micro- differences in sealant thickness during actual assembly, such as uneven application or varying clamping forces, will accumulate after all cylinder block segments 1 are finally connected in series. This will ultimately lead to significant flatness errors at the frame end 4 or cylinder head end 5 of the overall cylinder block 3, affecting assembly and easily causing structural stress concentration.

[0027] In this embodiment, the segmented cylinder block 1 has ten segments, such as... Figure 1As shown, the functional cylinder 2 is located at the position of the sixth segment cylinder 1. There are five effective cylinders 7 on one side of the functional cylinder 2 and four effective cylinders 7 on the other side. Each segment cylinder 1 is pre-processed to obtain the finished product. The opposite surfaces between adjacent segment cylinders 1 are the connecting surfaces 8. The connecting surfaces 8 are provided with positioning pin holes and bolt holes. The positioning pin holes are used with positioning pins to align adjacent segment cylinders 1. The bolt holes are used with bolts and other fasteners to connect and fix adjacent segment cylinders 1. In order to ensure sealing, adhesive is also required at the connecting surfaces 8. The adhesive application position avoids the connection position of the positioning pin holes and bolt holes. When connecting, the connection between segment cylinders 1 is carried out in accordance with the WinGD connection specification.

[0028] like Figure 1 As shown, the segmented cylinder bodies 1 are arranged in sequence before connection, with the cylinder head end 5 facing down and the frame end 4 facing up. The bottom is raised using level supports to provide physical space for subsequent flipping operations. Before connection, the connecting surfaces 8 of the segmented cylinder bodies 1 are glued, and locating pins and fasteners are precisely installed. After all the segmented cylinder bodies 1 are connected in sequence to form the integral cylinder body 3, the gantry milling machine is started, and the upward-facing frame end 4 is first subjected to continuous planar machining.

[0029] like Figure 2 As shown, the loosely segmented cylinder body 1 is connected into a whole component by applying glue, pinning and bolting. At this time, the whole component is processed by a gantry milling machine. The cutting tool of the gantry milling machine continuously mills the entire frame end 4 under a unified coordinate system. This absorbs and masks the cumulative dimensional chain error caused by the uneven thickness of the sealant at each internal joint from a macroscopic physical level, so that the overall flatness of the frame end 4 is well guaranteed.

[0030] The support system used for the bottom elevation consists of multiple rigid support components with calibrated heights, such as 300mm high square boxes distributed in a matrix on the workshop floor, with a heavy-duty gantry milling machine straddling above them.

[0031] The side of the segmented cylinder body 1 is a connecting surface 8. The edge of the connecting surface 8 is opened to form a flange structure. The locating pin is inserted into the locating pin hole to limit radial slippage. The tension bolt passes through the reserved bolt hole to provide axial locking force.

[0032] When connecting adjacent segmented cylinder blocks 1, hydraulic tools are used to gradually apply preload to complete the overall assembly. Subsequently, the crossbeam of the gantry milling machine descends, and the large-diameter milling cutter head on the main bearing starts to rotate. The cutter head feeds smoothly along the longitudinal X-axis and transverse Y-axis of the integral cylinder block 3. Amidst the sound of metal cutting, the milling cutter gradually processes the uneven blank surface of the frame end 4 into a flat, continuous, and uniform mounting reference surface with a metallic luster.

[0033] After machining the frame end 4, the entire cylinder body must be rotated 180 degrees so that the cylinder head end 5 faces upwards for the next machining step. However, the total weight after assembly reaches approximately 200 tons, while the combined lifting capacity of single or multiple overhead cranes in a typical heavy machinery workshop often has an upper limit, which is less than 200 tons. This exceeds the lifting limit, and forced lifting could easily damage the equipment or even cause a major workshop collapse accident. Furthermore, the internal structure of the functional cylinder body 2 differs from that of the effective cylinder body 7, resulting in significant differences in total weight and weight distribution. If it is arbitrarily segmented, the combined section with the functional cylinder body 2 will experience a severe shift in the center of gravity during lifting.

[0034] In this regard, such as Figure 3 As shown, in this embodiment, the segmented cylinder 1 includes an effective cylinder 7 and a functional cylinder 2. The same number of effective cylinders 7 are connected to both sides of the functional cylinder 2, so that the functional cylinder 2 is located at the center of the combined cylinder 9 to which it belongs. The center of gravity of the combined cylinder 9 to which the functional cylinder 2 belongs is located at the center of the functional cylinder 2, so that the attitude control is convenient when the combined cylinder 9 is in a flipping posture.

[0035] When performing attitude control, steel wire ropes, chains, etc. can be connected to the segmented cylinder 1. The end of the steel wire rope can be connected to a fixed traction machine. The position of the segmented cylinder 1 can be controlled by the traction machine winding or releasing the steel wire rope to prevent the segmented cylinder 1 from going out of control during the flipping process.

[0036] It should be noted that the tilting of the combined cylinder 9 can be achieved by using lifting equipment such as overhead cranes or gantry cranes, with a lifting device connected to a flexible cable, which is then connected to the combined cylinder 9, thereby performing operations such as traction, lifting, and lowering of the combined cylinder 9 to achieve tilting; alternatively, a dedicated load-bearing tilting device can be used to drive the combined cylinder 9 to rotate and adjust.

[0037] Specifically, in this embodiment, a lifting device is used to flip the combined cylinder 9. Based on the lifting capacity of the lifting device, the overall cylinder 3 is divided and disassembled so that the weight of each group of combined cylinders 9 is less than or equal to the maximum lifting capacity of the lifting device. This ensures that the lifting device operates within the maximum lifting capacity range when lifting and flipping each group of combined cylinders 9, avoiding the risk of equipment damage and safety accidents caused by overload lifting. This allows the ultra-heavy main cylinder flipping processing task, which was originally limited by the workshop lifting bottleneck, to be carried out smoothly.

[0038] like Figure 3 As shown, the combined cylinder block 9 comprises at least two connected segments. During the segmentation planning, the functional cylinder block 2 is ensured to be located at the geometric center of its respective combined cylinder block 9, and the functional cylinder block 2 is connected to the same number of effective cylinder blocks 7 on both sides, as shown below. Figure 3As shown, the combined cylinder 9 corresponding to the functional cylinder 2 includes the effective cylinder 7, the functional cylinder 2, and the effective cylinder 7 arranged sequentially, forming a three-section combination. For the functional cylinder 2 with uneven weight distribution, by retaining an equal number of conventional effective cylinders 7 on both sides as counterweights, the lever balance principle is used to forcibly pull the overall center of gravity of this combined section back to near the physical symmetry plane, thereby reducing the overturning moment during lifting and providing a stable mechanical premise for subsequent safe overturning. This allows older shipyards or manufacturing bases with limited lifting hardware to undertake the production of ultra-large dual-fuel main engines, avoiding the need to spend huge sums upgrading the workshop crane system for a single project.

[0039] When the heavy combined cylinder 9 is rotated 180 degrees, if the traditional lifting point distribution method is used, the positioning pin holes and bolt holes are used as lifting points to thread steel wire ropes, etc. The orientation adjustment impact force during the rotation process can easily cause deformation of the positioning pin holes and bolt holes. Furthermore, the steel wire rope passing through the positioning pin holes and bolt holes can easily scratch the connecting surface 8, causing the sealant on the connecting surface 8 to fail, and even damaging the flatness and roughness of the connecting surface 8.

[0040] In this embodiment, the lifting equipment uses a flexible cable attached to its hook. The flexible cable passes through the vertically distributed cylinder holes 6 of the segmented cylinder body 1, gradually flipping the combined cylinder body 9. The flexible cable can also be a high-strength synthetic fiber sling, thus avoiding the connecting surface 8. Simultaneously, the center of the end faces of the frame end 4 and cylinder head end 5 of the segmented cylinder body 1 are concave, effectively avoiding the machining positions of the frame end 4 and cylinder head end 5 during the flexible cable insertion, ensuring accuracy. The flexible cable passes through the cylinder holes of the combined cylinder body 9 from top to bottom, and is connected at the bottom by a dedicated horizontal lifting beam or flexible protective sleeve, forming a "U"-shaped force circuit. The raised space between the bottom of the segmented cylinder body 1 and the ground provides a passage for the flexible cable to pass through.

[0041] The flipping process is carried out in two steps: first, flip it 90° to make the segmented cylinder 1 lie flat, and then flip it 90° to flip the entire segmented cylinder 1.

[0042] Furthermore, after the cylinder block 9 is flipped, the protrusion 10 on the side of the segmented cylinder block 1, which is used to connect the exhaust pipe or the intake box, often occupies a lot of space and may even physically interfere with the column of the gantry milling machine or the workshop logistics channel. To address this, after flipping the combined cylinder block 9, the position of the combined cylinder block 9 is adjusted and the combined cylinder block 9 is controlled to rotate half a turn, so that the protrusion 10 on the cylinder head end 5 side of the combined cylinder block 9 is located in a clearance position away from the operating space, thus avoiding the equipment in the operating space.

[0043] When the lifting equipment is hoisting the combined cylinder body 9, the ground-based tilting assembly can also assist. The lifting equipment slowly raises the hook, and the flexible cable gradually tightens under stress, fitting against the inner wall of the cylinder bore 6 without causing scratches. With the guide support of the bottom tilting assembly, the combined cylinder body 9 slowly moves away from the support and smoothly completes a 180-degree longitudinal roll in mid-air or on a dedicated tilting frame, so that the cylinder head end 5 faces upwards. Figure 4 As shown, before landing, the trolley or hook rotation mechanism of the crane is started, which drives the combined cylinder 9 suspended in the air to rotate smoothly 180 degrees on the horizontal plane, and finally the protrusion 10 falls towards the back of the workshop wall or column.

[0044] After the combined cylinder block 9 is flipped and its posture adjusted, it needs to be reassembled into a complete 10-cylinder length. However, due to the disturbances caused by disassembly, hoisting, and flipping, the original assembly state has been disrupted. The original integral cylinder block 3, which was placed face down on the support after the initial connection, is prone to step differences or angular tilting at the joints of the very flat frame end 4. If the cylinder head end 5 and the sides are machined under such micro-deformation with accumulated misalignment, it will eventually cause the upper and lower reference surfaces of the engine to lose parallelism, resulting in uneven stress on the crankshaft and cylinder head during assembly.

[0045] In this embodiment, when reconnecting adjacent cylinder blocks 9 to form an integral cylinder block 3, the cylinder blocks 9 need to be continuously adjusted. The machining system is used to strictly control the flatness of the machined frame ends 4 of adjacent cylinder blocks 9 within a set range. The segmented cylinder blocks are then reassembled into a single unit. At this point, the cylinder head end 5, as the blank to be machined, faces upwards, and the frame end 4 faces downwards and rests stably on multiple equal-height support members. The universal milling head of the gantry milling machine is suspended above the cylinder block 9.

[0046] The disassembled flange surface is re-glued, and the locating pin is inserted in its original position. The lower frame end 4 forms a surface contact support relationship with the support component of equal height. When the fastening bolts are inserted but not completely locked, a laser tracker or micrometer is used to measure the seam at the bottom frame end 4 joint. By fine-tuning the height of the support component or using a hydraulic jack to fine-tune the cylinder body posture, it is confirmed that the flatness difference between the two ends of the frame end 4 at the joint has returned to the set range, and then the fasteners are completely locked. The gantry milling machine spindle descends and processes the plane of the top cylinder head end 5 along the X / Y axis; then the spindle milling head deflects 90 degrees or a side milling head is used to feed along the Z / Y axis to continuously mill and bore the exhaust port surface and inspection door surface on the side of the cylinder body, completing the global machining of the cylinder head end 5 and the circumferential side of the entire cylinder body 3.

[0047] In this embodiment, the flatness of the frame end 4 of the adjacent combined cylinder 9 is within 0.1mm. When connecting fasteners, the fasteners are installed and tightened in a diagonal order.

[0048] Example 2 In another typical embodiment of the present invention, such as Figure 1 - Figure 5 As shown, a segmented cylinder machining system for marine engines is presented, which performs the surface treatment process of the marine main engine cylinder block as described in Example 1.

[0049] It includes a tilting assembly, a gantry milling machine, and multiple equal-height support components. The multiple equal-height support components are used to support the segmented cylinder 1. The tilting assembly is connected to the combined cylinder 9 to drive the combined cylinder 9 to adjust its posture. The gantry milling machine is mounted above the segmented cylinder 1, and the milling head of the gantry milling machine can be adjusted to the top and side of the segmented cylinder 1.

[0050] Among them, multiple equal-height support components can be heavy-duty support columns made of high-strength alloy steel or cast iron. Their tops are precision ground and distributed in an array, fixed on the heavy-duty bearing foundation of the workshop, forming the physical base of the entire processing system.

[0051] Before the cylinder block is hoisted into place, a laser tracker or a high-precision level is used to check the level of the top surface of all the supporting components to ensure that they are on the same horizontal plane. This provides a stable and rigid support for the cylinder block, which weighs up to 100 tons, and eliminates the structural deformation caused by suspension or unevenness due to its own weight. In addition, it can also provide a physical reference plane for the overall assembly of the segmented cylinder block 1 and the combined cylinder block 9. At the same time, its height design is just right to leave space at the bottom for the hoisting straps to pass through and for the exhaust pipes to avoid.

[0052] The tilting assembly can be achieved using a crane, or it can be assisted by adding a heavy-duty hydraulic tilting frame, a dedicated lifting beam with rotary drive, or a follow-up positioner. When the crane lifts the combined cylinder 9 upwards, it provides a stable and controllable rotational torque, transforming simple vertical lifting into controllable spatial tumbling, guiding the combined cylinder 9 to tilt.

[0053] A gantry milling machine is a large CNC gantry machining center that spans above a level support structure. It includes two columns, a worktable that can move a long distance along the X-axis, and a ram that can move along the Y and Z axes. The ram end is equipped with a universal milling head or a right-angle side milling head that can automatically change position.

[0054] After the cylinder blocks are closed and stabilized, the gantry milling machine starts. All cylinder block segments 1 are integrated into a unified global three-dimensional coordinate system. The main milling head first performs large-area planar milling on the frame end 4 above the overall cylinder block 3; after the cylinder block segments 1 are adjusted in posture, the cylinder head end 5 is planar milled. Then, the milling head is controlled to deflect 90 degrees, and the milling cutter is rotated to the side of the cylinder block. Along the X / Y axis, it performs side milling and boring on various intake and exhaust flange surfaces and inspection windows on the side.

[0055] Example 3 In another embodiment of this invention, a marine engine is proposed, which is processed by the above-mentioned marine main engine cylinder surface treatment process.

[0056] Because the cylinders of this marine engine are manufactured using a process of first applying adhesive and then milling as a whole, the cylinder head mounting surface at the top and the frame connection surface at the bottom form a continuous geometric whole from cylinder 1 to cylinder 10. When assembled onto the engine frame, there are no step differences at the joints, eliminating local stress concentration, improving the overall structural rigidity of the engine, and better resisting the adverse effects of hull deformation.

[0057] Due to the flexible cable hoisting and center-of-gravity balancing configuration used in the process, the machined surface of the combined cylinder block 9 is not scratched after being flipped and adjusted. Furthermore, since the cylinder bore 6 is machined after assembly, any scratches caused during posture adjustment can be addressed in subsequent processing. This ensures the cylindricity and fit of the cylinder liner during subsequent press-fitting, thereby achieving smooth reciprocating motion of the piston and effectively extending the friction life of the cylinder liner and piston rings.

[0058] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A surface treatment process for marine main engine cylinder blocks, characterized in that, include: All the segmented cylinder blocks are connected in sequence to form an integral cylinder block. The cylinder head end of the integral cylinder block faces down, and the frame end of the integral cylinder block faces up. The frame end of the integral cylinder block is machined. The overall cylinder block is divided into multiple sets of combined cylinder blocks. Each combined cylinder block includes at least two connected segmented cylinder blocks, and the functional cylinder block is located at the center of its combined cylinder block. Each cylinder block is flipped so that the cylinder head is facing upwards, and all cylinder blocks are reconnected to form a single cylinder block. The cylinder head and the circumferential sides of the single cylinder block are then machined.

2. The surface treatment process for marine main engine cylinder blocks as described in claim 1, characterized in that, Before connecting the segmented cylinder blocks, they are arranged in sequence with the cylinder head end facing down and the frame end facing up, and the bottom is raised to leave space for flipping operations.

3. The surface treatment process for marine main engine cylinder blocks as described in claim 2, characterized in that, Before connecting the segmented cylinder blocks, the connecting surfaces are coated with adhesive, and locating pins and fasteners are installed.

4. The surface treatment process for marine main engine cylinder blocks as described in claim 1, characterized in that, The segmented cylinder block includes an effective cylinder block and a functional cylinder block, with the same number of effective cylinder blocks connected to each side of the functional cylinder block.

5. The surface treatment process for marine main engine cylinder blocks as described in claim 1 or 4, characterized in that, Before using lifting equipment to flip the combined cylinder body, the entire cylinder body is divided according to the lifting capacity of the lifting equipment, so that the weight of each group of combined cylinder bodies after division is less than or equal to the maximum lifting capacity of the lifting equipment.

6. The surface treatment process for marine main engine cylinder blocks as described in claim 5, characterized in that, The lifting equipment has a hook with a flexible cable that passes through the vertically distributed cylinder holes of the segmented cylinder body, and rotates the combined cylinder body step by step.

7. The surface treatment process for marine main engine cylinder blocks as described in claim 1, characterized in that, After flipping the combined cylinder, adjust its position and control it to rotate half a turn so that the protrusion on one side of the cylinder head is in a clearance position away from the operating space, thus avoiding the equipment in the operating space.

8. The surface treatment process for marine main engine cylinder blocks as described in claim 1, characterized in that, When reconnecting adjacent cylinder blocks, adjust the cylinder blocks and control the flatness of the frame end of the adjacent cylinder blocks within the set range.

9. A segmented cylinder machining system for marine engines, used to perform the surface treatment process of the marine main engine cylinder block as described in any one of claims 1-8, characterized in that, It includes a tilting assembly, a gantry milling machine, and multiple level support components. The level support components are used to support the segmented cylinder body. The tilting assembly is connected to the combined cylinder body to drive the combined cylinder body to adjust its posture. The gantry milling machine is mounted above the segmented cylinder body, and the milling head of the gantry milling machine can be adjusted to the top and side of the segmented cylinder body.

10. A marine engine, characterized in that, It is obtained by the surface treatment process of the ship main engine cylinder block as described in claims 1-8.

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