Method for dismantling crankshaft of marine large generator at wharf

Abstract

The invention discloses a method for dismantling a crankshaft of a marine large generator at a wharf. The method specifically comprises the following steps that S1, a piston and a crankshaft connecting rod of a shell of the crankshaft of the generator are dismantled, and a shipping lifting lug is installed on a cylinder body assembly; s2, a bottom shock absorber of a base on the lower portion of the generator is dismounted, and a jacking stand column and a hydraulic jack are installed under the shock absorber; s3, cantilever beams are installed at the two ends of the crankshaft, the cantilever beams are jacked through a hydraulic jack, and after jacking of the cylinder body assembly is completed, a temporary support is installed below the crankshaft, and the crankshaft is supported and fixed; s4, a translation tool is placed on the generator oil pan, and the translation tool is perpendicular to the length direction of the crankshaft; s5, the crankshaft is separated from the cylinder body assembly, a temporary support below the crankshaft is dismounted, and the crankshaft is lowered to the translation tool through a lifting lug; and the crankshaft is moved out through the translation tool. Through the use of the jacking tool and the translation tool, forming of a process hole is avoided, and the safety of crankshaft maintenance and replacement work of the large generator is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of shipbuilding, and in particular relates to a method for dismantling a crankshaft of a large marine generator at a dock. Background Art

[0002] Large dual-fuel generators are the source of electricity for LNG ships. During daily operations, the generator sets need to undergo routine maintenance. When the ship was first designed, periodic routine maintenance inspections were taken into consideration, so a crane beam was installed above the generator room to facilitate the maintenance inspection of the generator equipment.

[0003] When the generator equipment is in operation, a component damage accident outside the conventional design considerations occurs, and the generator equipment needs to be disassembled for repair. The crane beam configured in the generator room cannot meet the needs of the lifting operation. If the generator crankshaft needs to be repaired and replaced, since it is located inside the generator prime mover, the prime mover cylinder assembly needs to be removed for repair and replacement. It is necessary to find a suitable location in the hull structure to open a large process hole, use external crane resources to lift the cylinder assembly out of the ship's generator room, and then repair and replace the crankshaft. Therefore, the repair and replacement operations need to be carried out in the dock, and the workload is large, the construction period is long, and the safety during the construction process is low. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies in the above-mentioned prior art and to provide a method for dismantling the crankshaft of a large marine generator at a dock. Compared with conventional schemes, the present invention uses jacking tooling and translation tooling to open large process holes and cooperate with external cranes in construction, thereby reducing peripheral workload and improving the safety of large generator crankshaft maintenance and replacement work.

[0005] In order to achieve the above invention purpose, the technical solution provided by the present invention is as follows:

[0006] A method for dismantling a crankshaft of a large marine generator at a dock, the method specifically comprising the following steps:

[0007] S1, remove the piston and crankshaft connecting rod of the generator crankshaft housing, and install the lifting lug on the cylinder assembly;

[0008] S2, remove the bottom shock absorber of the lower base of the generator, and install a jacking column and a hydraulic jack just below the shock absorber;

[0009] S3, install cantilever beams at both ends of the crankshaft. The cantilever beams are installed just above the jacking columns. The cantilever beams are lifted by hydraulic jacks to lift the cylinder assembly to the required height. After the cylinder assembly is lifted, a temporary support is installed under the crankshaft to fix the crankshaft support.

[0010] S4, placing a translation tool on the generator oil pan, wherein the translation tool is perpendicular to the length direction of the crankshaft;

[0011] S5, separate the crankshaft from the cylinder assembly, remove the temporary support under the crankshaft, lower the crankshaft onto the translation tooling through the lifting lugs; move the crankshaft out through the translation tooling to complete the removal of the crankshaft.

[0012] Furthermore, the lifting lug in S1 is installed at the upper end of the generator cylinder liner, the lifting lugs are respectively installed at both ends of the generator cylinder liner, and the crankshaft is suspended in the air by connecting the lifting lugs with a hand winch.

[0013] Furthermore, there are eight bottom shock absorbers on the lower base of the generator. After the shock absorbers are removed, the jacking tooling is inserted into the base position of the shock absorbers, and the jacking tooling is fastened to the shock absorber base through the bolts provided on the shock absorbers.

[0014] Furthermore, the cylinder assembly jacking is specifically as follows: after cantilever beams are installed at both ends of the crankshaft, the jack on the cantilever beam lifts the cantilever beam to lift the crankshaft. When the jack reaches the maximum stroke, a plurality of temporary supports are evenly arranged under the crankshaft between the lifting columns. The temporary supports support the crankshaft, and the height of the lifting columns is adjusted so that the distance between the lifting columns and the cantilever beam is within the lifting range of the jack. After the adjustment of the lifting columns is completed, the jack is used to repeat the lifting to lift the crankshaft to a predetermined height. At the same time, the temporary columns are removed to complete the lifting of the cylinder assembly.

[0015] Furthermore, the translational tooling is a roller structure, which is laid flat on both sides of the generator oil pan, and temporary supports are provided under the translational tooling to keep the translational tooling horizontal. A supporting wooden board is laid on the translational tooling, and the lifted crankshaft is hung on the wooden board. The wooden board is pulled to move the crankshaft to the outside of the generator, thereby completing the removal of the crankshaft.

[0016] Based on the above technical solution, the method for dismantling the crankshaft of a large marine generator at a dock in the present invention has achieved the following technical advantages through practical application:

[0017] 1. The method of dismantling the crankshaft of a large marine generator at a dock of the present invention uses a jacking tool and a translation tool. Compared with the conventional solution of opening a large process hole and cooperating with an external crane for construction, the peripheral workload is reduced and the safety of the work of repairing and replacing the crankshaft of a large generator is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of crankshaft replacement in a method for dismantling a crankshaft of a large marine generator at a dock according to the present invention.

[0019] Figure 2 The present invention is a schematic diagram of crankshaft lifting in a method for dismantling a crankshaft of a large marine generator at a dock.

[0020] Figure 3 A schematic diagram of crankshaft translation in a method for dismantling a crankshaft of a large marine generator at a dock according to the present invention. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is described below by the specific examples shown in the accompanying drawings. However, it should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0022] like Figure 1-3 As shown, the present invention belongs to a method for dismantling a crankshaft of a large marine generator at a dock, and the method specifically comprises the following steps:

[0023] S1, remove the piston of the generator crankshaft 1 housing and the connecting rod of the crankshaft 1, and install the lifting lug on the cylinder assembly;

[0024] S2, remove the bottom shock absorber of the lower base of the generator, and install the jacking column 2 and the hydraulic jack 5 just below the shock absorber;

[0025] S3, install cantilever beams at both ends of the crankshaft 1, the cantilever beams are installed directly above the jacking column 2, and the cantilever beams are lifted by the hydraulic jack 5 to lift the cylinder assembly to the required height; after the cylinder assembly is lifted, install a temporary support 3 under the crankshaft 1 to support and fix the crankshaft 1;

[0026] S4, placing a translation tool 4 on the generator oil pan, wherein the translation tool 4 is perpendicular to the length direction of the crankshaft 1;

[0027] S5, separate the crankshaft 1 from the cylinder assembly, remove the temporary support 3 under the crankshaft 1, and lower the crankshaft 1 onto the translation tooling 4 through the lifting ears; move the crankshaft 1 out through the translation tooling 4 to complete the removal of the crankshaft 1.

[0028] By using the jacking tooling and the translation tooling 4, compared with the conventional solution of opening a large process hole and using an external crane to cooperate in the construction, the peripheral workload is reduced and the safety of the work of repairing and replacing the crankshaft 1 of a large generator is improved.

[0029] The lifting lug in S1 is installed on the upper end of the generator cylinder sleeve, and the lifting lugs are respectively installed at both ends of the generator cylinder sleeve, and the crankshaft 1 is suspended in the air by connecting the lifting lugs with a hand chain hoist.

[0030] There are eight bottom shock absorbers on the lower base of the generator. After the shock absorbers are removed, the jacking tooling is inserted into the base position of the shock absorbers, and the jacking tooling is fastened to the shock absorber base through the bolts provided on the shock absorbers.

[0031] The cylinder assembly jacking is specifically as follows: after cantilever beams are installed at both ends of the crankshaft 1, the jack 5 on the cantilever beam lifts the cantilever beam to lift the crankshaft 1. When the jack 5 reaches the maximum stroke, a plurality of temporary supports 3 are evenly arranged below the crankshaft 1 between the lifting columns 2. The temporary supports 3 support the crankshaft 1. The height of the lifting columns 2 is adjusted so that the distance between the lifting columns 2 and the cantilever beam is within the lifting range of the jack 5. After the adjustment of the lifting columns 2 is completed, the jack 5 repeats the jacking to lift the crankshaft 1 to a predetermined height. At the same time, the temporary supports 3 are removed to complete the jacking of the cylinder assembly.

[0032] The translation tooling 4 is a roller structure, which is laid flat on both sides of the generator oil pan, and a temporary support 3 is placed under the translation tooling 4 to keep the translation tooling 4 in a horizontal state. A supporting wooden board is laid on the translation tooling 4, and the lifted crankshaft 1 is hung on the wooden board. The wooden board is pulled to move the crankshaft 1 to the outside of the generator, thereby completing the removal of the crankshaft 1.

[0033] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the specific implementation methods of the invention can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the present invention, which should be included in the scope of the technical solution for protection of the present invention.

Claims

1. A method for dismantling a large marine generator crankshaft at a dock, characterized in that: The method specifically comprises the following steps: S1, remove the piston and crankshaft connecting rod of the generator crankshaft housing, and install the lifting lug on the cylinder assembly; S2, remove the bottom shock absorber of the lower base of the generator, and install a jacking column and a hydraulic jack just below the shock absorber; S3, install cantilever beams at both ends of the crankshaft. The cantilever beams are installed just above the jacking columns. The cantilever beams are lifted by hydraulic jacks to lift the cylinder assembly to the required height. After the cylinder assembly is lifted, a temporary support is installed under the crankshaft to fix the crankshaft support. S4, placing a translation tool on the generator oil pan, wherein the translation tool is perpendicular to the length direction of the crankshaft; S5, separate the crankshaft from the cylinder assembly, remove the temporary support under the crankshaft, lower the crankshaft onto the translation tooling through the lifting lugs; move the crankshaft out through the translation tooling to complete the removal of the crankshaft.

2. A method for dismantling a large marine generator crankshaft at a dock according to claim 1, characterized in that: The lifting lug in S1 is installed on the upper end of the generator cylinder sleeve, and the lifting lugs are respectively installed at both ends of the generator cylinder sleeve, and the crankshaft is suspended in the air by connecting the lifting lugs with a hand winch.

3. The method for dismantling a large marine generator crankshaft at a dock according to claim 1, characterized in that: There are eight bottom shock absorbers on the lower base of the generator. After the shock absorbers are removed, the jacking tooling is inserted into the base position of the shock absorbers, and the jacking tooling is fastened to the shock absorber base through the bolts provided on the shock absorbers.

4. The method for dismantling a large marine generator crankshaft at a dock according to claim 1, characterized in that: The cylinder assembly jacking is specifically as follows: after cantilever beams are installed at both ends of the crankshaft, the jack on the cantilever beam lifts the cantilever beam to lift the crankshaft. When the jack reaches the maximum stroke, a plurality of temporary supports are evenly arranged below the crankshaft between the lifting columns. The temporary supports support the crankshaft, and the height of the lifting columns is adjusted so that the distance between the lifting columns and the cantilever beam is within the lifting range of the jack. After the adjustment of the lifting columns is completed, the jack is repeatedly lifted to lift the crankshaft to a predetermined height. At the same time, the temporary columns are removed to complete the jacking of the cylinder assembly.

5. The method for dismantling a large marine generator crankshaft at a dock according to claim 1, characterized in that: The translation tooling is a roller structure, which is laid flat on both sides of the generator oil pan, and temporary supports are placed under the translation tooling to keep the translation tooling horizontal. Support wooden boards are laid on the translation tooling, and the lifted crankshaft is hung on the wooden boards. The wooden boards are pulled to move the crankshaft to the outside of the generator, thereby completing the removal of the crankshaft.

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