Aligning and connecting tool for segmented crankshaft of main engine for ultra-large ship

Abstract

A guide cylinder is arranged on the front section of a body 5, an oil cylinder 3 and an oil cylinder cover are arranged on the rear section of the body 5, a piston is arranged in the oil cylinder, a guide rod at the front end of the piston penetrates through the front wall of the oil cylinder to extend out, a connecting shaft sleeve at the front end of the guide rod is connected with a stretching wedge shaft 7, and the stretching wedge shaft is matched with a wedge block sleeve 6; the rear end of the wedge sleeve is opposite to the front end of the guide cylinder, and the outer edge of the connecting shaft sleeve is movably matched with the guide cylinder. A stroke indicating rod 1 at the rear end of the piston penetrates through an oil cylinder cover, and stroke scales are arranged outside the stroke indicating rod. And the oil cylinder wall is provided with an oil duct which is communicated with a pressurizing port 8 in front of the oil cylinder cavity and is provided with a pressurizing pipe joint. And an oil duct 4 is arranged on the oil cylinder wall and communicated with an oil return port 2 and a pipe joint behind the oil cylinder cavity. The device is simple and convenient to use and light in weight, and achieves the functions of wide load adjustment range, accurate centering and omni-directional adjustment.

Description

Technical Field

[0001] Modern ultra-large marine main engines (taking 9X92B as an example, the total weight exceeds 1,600 tons, and the subsequent examples all take the 9X92B main engine as an example) are very heavy and large in size. Limited by the crane capacity and transportation tools of the shipyard and main engine factory, their large parts usually adopt a segmented design. After the main engine is assembled and tested on the test bench of the main engine factory, it must be disassembled into several large sections before it can be shipped to the shipyard for final assembly. The crankshaft is the heaviest single large part on the main engine (weighing more than 350 tons). Although it is a moving part, it also adopts a segmented design. It must also be connected in sections at the main engine factory, and then disassembled and sent to the shipyard after the test run. The development and application of this technology is to solve the problem of alignment and disassembly of segmented crankshafts in the main engine factory. Background Art

[0002] The weight of the segmented crankshaft is large (the segment exceeds 170 tons), and the shaft alignment requires high precision (coaxiality within 0.05mm), requiring the alignment tool to have a large omnidirectional adjustment ability and high alignment accuracy. The crankshaft transmits a large torque (the maximum torque is nearly 700,000 N m), so the connecting bolts must have a sufficiently large design strength. In addition, when shipped to the shipyard for reinstallation, the bolt holes must have good dimensional accuracy and finish, which requires that the crankshaft bolt holes must not have scratches after the main engine factory test run. Unlike the one-time assembly of finished products in the shipyard without disassembly, the main engine factory has dozens of main engines in the same series. Considering the cost, the connecting bolts need to be reused many times. Therefore, the main engine factory's segmented crankshaft alignment connection has higher and more stringent technical requirements. Traditional technical solutions cannot take into account the above stringent requirements, and it is necessary to develop and apply new technical solutions and connection tooling. Summary of the invention

[0003] This technology development and application includes the development and application of the main engine crankshaft segment connection operation tool. In terms of operation tools, we have developed and applied the ultra-large marine main engine segment crankshaft alignment connection tooling (see Figure 1 ), suitable for the main engine factory to disassemble and assemble multiple times without damaging the bolt hole cone sleeve hydraulic connection bolt assembly (such as Figure 2 ), as well as hydraulic tensioning for taper sleeve tensioning and bolt tightening, which provides convenience and efficiency for the centering and alignment of crankshaft segments, installation of taper sleeve bolts and disassembly.

[0004] The technical solution of the present invention is:

[0005] The super-large marine main engine segmented crankshaft alignment connection tool (hereinafter referred to as the centering tool or tool) has a main body, the front section of the main body is a guide cylinder, the rear section of the main body is a cylinder, the rear end of the cylinder is equipped with a cylinder cover, and the inner cavity of the cylinder is equipped with a piston. The guide rod with the front end of the piston extends through the guide hole of the front wall of the cylinder, and the front end of the guide rod is connected to the stretching wedge shaft through a coupling sleeve. The outside of the stretching wedge shaft is equipped with a wedge sleeve; the rear end of the wedge sleeve is opposite to the front end of the guide cylinder, and the outer edge of the coupling sleeve is dynamically matched with the inside of the guide cylinder. The stroke indicator rod with the rear end of the piston passes through the stroke hole of the cylinder cover, and the stroke indicator rod has a stroke scale on the outside. The cylinder wall is opened with a flow channel to connect the pressure port in front of the cylinder cavity, and the pressure port has a pressure pipe joint. The cylinder wall is opened with a flow channel to connect the oil return port behind the cylinder cavity, and the oil return port has a joint for the return pipe.

[0006] Use the following tools according to the operating instructions to align, install and disassemble the segmented crankshaft.

[0007] 1Hydraulic centering tooling, as shown in the figure, pressurized oil is injected from the pressure port, the stretching cylinder plunger drives the stretching wedge shaft to move left, and the inclined surface on the wedge shaft drives the wedge surface to move outward. This mechanism converts the axial tension of the hydraulic cylinder into radial tension of the wedge block to the surroundings, forcing the two non-concentric bolt holes to be accurately aligned;

[0008] 2. Cone sleeve type tensioning hydraulic bolt assembly, as shown in the figure, is the core tooling for the development and application of this technology. The cone structure is used to expand the cone sleeve radially under the action of axial tension until the bolt\cone sleeve and the bolt hole form an interference fit. At this time, the force contact area between the bolt / cone sleeve and the bolt hole is the largest, the force is evenly applied to each part of the bolt hole, and the load between the bolts is also even. This will minimize the force per unit area of ​​the bolt hole. When the main engine is running at high load, the bolt hole will not be damaged by the bolt. When disassembling, the axial tension is released so that the bolt as a whole and the bolt hole can be restored to a clearance fit state. This not only facilitates the removal of the bolt, but also does not damage the bolt hole in the process. The bolt itself can also be kept in good condition and can be reused.

[0009] 3. Hydraulic tensioner: In order to ensure that the cone sleeve hydraulic bolt has reliable and balanced fastening strength, hydraulic tensioning is adopted. This can not only ensure the accuracy of the preload force, but also avoid the damage of the bolt and the bolt hole surface caused by rotational friction during the tightening of the cone sleeve bolt caused by torque preload. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 A schematic diagram of the structural alignment and connection tooling for the segmented crankshaft of a super-large marine main engine;

[0011] Figure 2 This is a schematic diagram of the installation of tapered sleeve hydraulic bolts after using the segmented crankshaft alignment connection tooling for super-large marine main engines. DETAILED DESCRIPTION

[0012] As shown in the attached figure Figure 1The illustrated ultra-large marine main engine segmented crankshaft alignment connection fixture has a body 5, the front section of the body is a guide cylinder, and the rear section of the body is a cylinder 3. The rear end of the cylinder is matched with a cylinder cover, and the inner cavity of the cylinder is matched with a piston. The guide rod with the front end of the piston extends through the guide hole of the front wall of the cylinder. The front end of the guide rod is connected to the stretching wedge shaft 7 through a coupling sleeve. The outside of the stretching wedge shaft is equipped with a wedge sleeve 6; the rear end of the wedge sleeve is opposite to the front end of the guide cylinder, and the outer edge of the coupling sleeve is dynamically matched with the inside of the guide cylinder. The stroke indicator rod 1 with the rear end of the piston passes through the stroke hole of the cylinder cover, and the stroke indicator rod has a stroke scale on the outside. The cylinder wall is opened with an oil channel connected to the pressure port 8 in front of the cylinder cavity, and the pressure port has a pressure pipe joint. The cylinder wall is opened with an oil channel 4 connected to the oil return port 2 behind the cylinder cavity, and the oil return port has a joint of the oil return pipe. Use a turning machine to roughly adjust the alignment of the bolt holes of the two crankshafts. When the coaxial accuracy of the crankshaft connecting bolt holes reaches within 1-2mm, select two bolt holes with an angular distance of 180° and install them into the hydraulic alignment tool. Driven by high-pressure hydraulic oil, the alignment tool expands to accurately align the bolt holes of the two crankshafts.

[0013] Install cone sleeve type tensioning hydraulic bolts into other bolt holes, install cone sleeve stop plates, and use hydraulic tensioners to stretch the bolts so that the bolts and cone sleeves fit completely and enlarge the cone sleeves to form an interference fit with the bolt holes, in preparation for the next step of hydraulically tightening the nuts. Of course, the hydraulic oil pressure for the above operations is regulated accordingly.

[0014] Install the hydraulic nuts on both sides and tighten the hydraulic nuts using a hydraulic tensioner. Install and tighten the cone sleeve bolts in all bolt holes (including the two bolt holes after removing the centering tool).

[0015] After the test run, disassemble it by loosening the hydraulic nut first, then injecting hydraulic oil between the bolt and the taper sleeve through the oil hole in the middle of the bolt, spreading the taper sleeve to separate the bolt and the taper sleeve, and taking out the bolt and the taper sleeve.

[0016] A hydraulic alignment tool was developed and applied for use in aligning segmented crankshafts of super-large marine main engines. The tool has the advantages of being easy to use, light weight, wide load adjustment range, precise alignment and omnidirectional adjustment. Cone-sleeve tensioning hydraulic bolts were applied for connecting segmented crankshafts of super-large marine main engines. The bolts have the advantages of high connection strength, easy assembly and disassembly without knocking or straining the bolt holes during use and disassembly. Construction specifications for segmented crankshaft connections were compiled. The specifications were based on the use of the above-mentioned tool and combined with the characteristics of segmented crankshafts to standardize the construction procedures and standards.

Claims

1. A super-large marine main engine segmented crankshaft alignment connection tool, characterized in that: The utility model has a main body, the front section of the main body is a guide cylinder, the rear section of the main body is an oil cylinder, the rear end of the oil cylinder is matched with an oil cylinder cover, the inner cavity of the oil cylinder is matched with a piston, the guide rod with the front end of the piston extends through the guide hole of the front wall of the oil cylinder, the front end of the guide rod is connected with the stretching wedge shaft through the coupling sleeve, and the outside of the stretching wedge shaft is matched with a wedge sleeve; the rear end of the wedge sleeve is opposite to the front end of the guide cylinder, and the outer edge of the coupling sleeve is movably matched with the inside of the guide cylinder.

2. The ultra-large marine main engine segmented crankshaft alignment and connection tooling according to claim 1, characterized in that: A stroke indicating rod provided at the rear end of the piston passes through the stroke hole of the oil cylinder cover, and a stroke scale is provided on the outer surface of the stroke indicating rod.

3. The ultra-large marine main engine segmented crankshaft alignment and connection tooling according to claim 1 or 2, characterized in that: A flow channel is opened on the oil cylinder wall to connect to the pressure port in front of the oil cylinder cavity, and the pressure port is provided with a pressure pipe joint.

4. The super-large marine main engine segmented crankshaft alignment and connection tooling according to claim 1 or 2, characterized in that: A flow channel is opened on the oil cylinder wall to connect to the oil return port at the rear of the oil cylinder cavity, and the oil return port is provided with a joint of the oil return pipe.

5. The super-large marine main engine segmented crankshaft alignment and connection tooling as claimed in claim 3, characterized in that: A flow channel is opened on the oil cylinder wall to connect to the oil return port at the rear of the oil cylinder cavity, and the oil return port is provided with a joint of the oil return pipe.

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