Marine main engine pre-positioning construction method

Abstract

The invention provides a ship main engine pre-positioning construction method which comprises the following steps: step 1, after a ship body section carrying structure of main engine pre-positioning is completed, the center line of a ship body is confirmed; 2, main engine pre-positioning irradiation is conducted according to the center line of the ship body; 3, main engine foot bolt scribing is conducted according to main engine pre-positioning irradiation and main engine foot hole arrangement; step 4, drilling a screw hole of the bottom foot of the main engine according to the lineation of the main engine base; 5, after the structural state meets the shaft-rudder system irradiation requirement and the ship body base line is checked to be qualified, shaft-rudder system irradiation is carried out according to the process requirement; step 6, hoisting the main machine; and 7, boring the stern shaft tube. The construction efficiency of ship building is effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of shipbuilding, and in particular to a method for pre-positioning a ship main engine. Background Art

[0002] Main engine positioning and hoisting is an important project in the shipbuilding process and a key node in the entire construction process of the ship in the dock (slipway). The completion status of this node directly affects the integrity of the ship when it is launched, and also lays the corresponding foundation for whether the mooring test after the ship is launched can be carried out smoothly.

[0003] With the advancement of shipbuilding technology, while ensuring shipbuilding quality, the implementation status of forward outfitting is a reflection of the shipbuilding technology and process level. Since main engine installation is directly related to the outfitting construction of the entire engine room area, including the construction integrity of the main engine-related piping and the installation plan of the engine room top deck, it directly affects the overall integrity of the entire engine room and, to a certain extent, affects subsequent construction plans above the engine room deck, such as the installation of a superstructure above the engine room, which will affect the installation and construction period of the superstructure. Therefore, to a certain extent, the positioning and installation nodes of the main engine during shipbuilding are important factors affecting the overall integrity of the ship's launch.

[0004] Currently, the main engine positioning is done by marking the centerline of the shaft system after the shaft and rudder system has been illuminated, drilling the main engine foot screw holes, and painting the main engine oil pan area before the main engine is hoisted. However, the technical state of the shaft and rudder system illumination places very high demands on the structure. The general principles are as follows:

[0005] (1) The welding and straightening work of the entire hull structure from the engine room front wall to the rear end of the stern tube, the bottom of the engine room area and the deck above it should be completed; the lifting of the sections or blocks to the main deck should be completed. The inspection results need to be confirmed by the shipowner and the ship surveyor.

[0006] (2) The double bottom tightness test of the above-mentioned areas is completed. This includes the tightness test of the stern tube cooling water tank and double bottom tank. The inspection results need to be confirmed by the shipowner and the ship surveyor.

[0007] (3) The hull baseline has been submitted to the shipowner and the ship surveyor. Summary of the Invention

[0008] In view of the shortcomings in the prior art, the present invention provides a method for pre-positioning a main engine of a ship.

[0009] The present invention achieves the above technical objectives through the following technical means.

[0010] A ship main engine pre-positioning construction method, comprising:

[0011] Step 1. After the hull section loading structure of the main engine pre-positioning is completed, confirm the hull centerline; Step 2. Carry out main engine pre-positioning lighting according to the hull centerline; Step 3. Mark the main engine foot bolts according to the main engine pre-positioning lighting and the main engine foot hole layout; Step 4. Drill the main engine foot screw holes according to the markings of the main engine base; Step 5. When the structural status meets the shaft and rudder system lighting requirements and the hull baseline is qualified, then carry out shaft and rudder system lighting according to the process requirements; Step 6. Carry out main engine hoisting; Step 7. Boring the stern shaft tube.

[0012] Furthermore, the hull section includes a stern tube, a shaft, a double bottom of the engine room and a side hull at the bottom of the engine room area.

[0013] Furthermore, the specific process of the main engine pre-positioning lighting is: lighting the shaft system according to the center line of the hull, confirming the processing allowances of the front and rear end faces of the stern tube and the stern bearing, and according to the arrangement of the main engine foot screw holes, determining the center positions of the screw holes at the four top corners of the main engine on the main engine base panel, determining the shaft system length and the position of the hull center line through pre-positioning lighting, and determining the height position of the shaft system center line through shaft system lighting.

[0014] Furthermore, the main engine foot bolt marking is specifically as follows: based on the four screw hole center point positions obtained by pre-positioning the main engine, the main engine base foot screw holes are marked according to the main engine foot hole arrangement, and the screw hole inspection circle is drawn according to the screw hole marking.

[0015] Furthermore, the processing accuracy of the main unit foot screw holes is confirmed by checking the circle.

[0016] Furthermore, the shaft rudder system lighting includes:

[0017] 1) Check the centerline of the main engine foot screw holes according to the centerline of the hull;

[0018] 2) Confirm the shafting centerline using the hull centerline and baseline height;

[0019] 3) Confirm the rudder system centerline and check whether the intersection relationship with the shaft system centerline meets the technical requirements;

[0020] 4) Use the centerline of the shafting system as the centerline of the stern tube to confirm the position of the machining circle of the stern tube bearing. At the same time, measure the length of the shafting system centerline based on the theoretical data from the rear end screw hole of the main engine to the rear end face of the stern tube to determine the machining amount of the rear end face of the stern tube;

[0021] 5) Confirm the height of the intermediate bearing base of the shaft system based on the center line of the shaft system.

[0022] Furthermore, the specific process of the main engine hoisting is: when the shaft system is preset to the shaft state, the main engine hoisting work is carried out according to the pre-positioned main engine base screw holes and the shaft system centerline height value confirmed by lighting the shaft system.

[0023] Furthermore, the specific process of boring the stern tube is as follows: the stern tube machining is carried out in parallel with the main engine hoisting, and the stern tube machining is carried out according to the optical data; the stern tube bearing is machined first, and then the front and rear end surfaces of the stern tube are machined.

[0024] The beneficial effects of the present invention are:

[0025] (1) The present invention adopts a method for pre-positioning the main engine based on the hull centerline after the stern tube, shaft, double bottom of the engine room and the side hull structure of the engine room area are completed. Since the structure from the stern tube to the engine room has been completed, the length data of the shaft system is ensured, and the side structure of the engine room bottom is completed, the corresponding hull center is also confirmed, and the height of the shaft system centerline is determined by the hull baseline, which does not affect the main engine pre-positioning work of the main engine foot screw hole processing, and the stern tube bearing and the front and rear end processing surfaces generally have a processing allowance of about 10mm, so in this state, the accuracy control of the subsequent hull installation can meet the requirements according to the principle process construction, and the accuracy control meets the technical requirements.

[0026] (2) The present invention realizes that the positioning and processing of the main engine foot screw holes are moved forward to before the shaft system is illuminated. After the shaft system is illuminated, the main engine hoisting work can be carried out directly, that is, the main engine hoisting is moved forward accordingly, which is beneficial to the deck capping of the engine room area, realizes the structural integrity of the engine room, lays the foundation for the integrity of the engine room outfitting, and effectively improves the construction efficiency of shipbuilding. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the main engine pre-positioning hull structure state of the present invention.

[0028] Figure 2 This is a schematic diagram of the pre-positioning and lighting of the host according to the present invention.

[0029] Figure 3 This is a schematic diagram of the lighting of the shaft rudder system of the present invention.

[0030] Figure 4 This is a schematic diagram of the structure of the ship's stern tube and its processed surface according to the present invention. DETAILED DESCRIPTION

[0031] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the protection scope of the present invention is not limited thereto.

[0032] This embodiment provides a method for pre-positioning a ship main engine, such as Figure 1 As shown, the following steps are included:

[0033] Step 1: Ship section loading status of main engine pre-positioning

[0034] like Figure 1 As shown in the figure, after the stern tube, shaft, engine room double bottom and engine room area bottom side hull structure are completed, the hull centerline is confirmed.

[0035] Step 2: Pre-position and illuminate the host

[0036] Host pre-positioning lighting Figure 2 As shown, the shafting system is illuminated along the hull centerline to confirm the machining allowances of the fore and aft ends of the stern tube and the stern bearing. The center positions of the screw holes at the four corners of the main engine are determined on the main engine base panel according to the main engine foot screw hole layout. Pre-positioning illumination is used to determine the shafting length and hull centerline position, and the height position of the shafting centerline is determined by illumination of the shafting system.

[0037] Step 3: Mark the main engine foot bolts

[0038] Based on the positions of the four screw hole centers obtained by pre-positioning the host, mark the screw holes of the host base feet according to the arrangement of the host foot holes, and draw the inspection circle of the screw holes based on the screw hole markings.

[0039] Step 4: Drilling screw holes for the host base

[0040] The screw holes are machined according to the markings on the main unit base, and the machining accuracy of the screw holes is confirmed by the inspection circle.

[0041] Step 5: Illuminate the rudder system

[0042] When the structural status meets the requirements for shaft and rudder system lighting and the hull baseline is qualified, the shaft and rudder system lighting shall be carried out according to the process requirements. Figure 3 As shown, it mainly includes the following contents:

[0043] 1) Check the centerline of the main engine foot screw holes according to the centerline of the hull.

[0044] 2) Confirm the shafting centerline using the hull centerline and baseline height.

[0045] 3) Confirm the rudder system centerline and check whether the intersection relationship with the shaft system centerline meets the technical requirements.

[0046] 4) Using the shafting centerline as the stern tube centerline, confirm the machining circle position of the stern tube bearing. Simultaneously, using the theoretical data from the rear end screw hole of the main engine to the rear end face of the stern tube, measure the length of the shafting centerline to determine the machining amount of the stern tube rear end face.

[0047] 5) Confirm the height of the intermediate bearing base of the shaft system based on the center line of the shaft system.

[0048] Step 6: Host hoisting

[0049] When the shaft system is preset to the shaft state, the main engine hoisting work is carried out according to the pre-positioned main engine foot screw holes and the shaft system centerline height value confirmed by lighting the shaft system.

[0050] Step 7: Boring the stern tube

[0051] The boring of the stern tube is as follows Figure 4 As shown, the stern tube machining is carried out in parallel with the main engine installation, and the stern tube machining is carried out according to the optical data. The stern tube bearing is machined first, and then the front and rear end surfaces of the stern tube are machined.

[0052] The embodiments described are preferred implementations of the present invention, but the present invention is not limited to the above implementations. Any obvious improvements, substitutions or modifications that can be made by those skilled in the art without departing from the essence of the present invention are within the scope of protection of the present invention.

Claims

1. A method for pre-positioning a ship main engine, characterized by: Step 1: After the hull section loading structure of the main engine pre-position is completed, confirm the hull centerline; Step 2: Perform main engine pre-position lighting according to the hull centerline; Step 3: Mark the main engine foot bolts according to the main engine pre-position lighting and the main engine foot hole layout; Step 4: Drill the main engine foot screw holes according to the markings of the main engine base; Step 5: When the structural status meets the shaft and rudder system lighting requirements and the hull baseline is qualified, then perform shaft and rudder system lighting according to the process requirements; Step 6: Hoist the main engine; Step 7: Boring the stern tube.

2. The ship main engine pre-positioning construction method according to claim 1 is characterized in that: The hull sections include a stern tube, a shaft, a double bottom of the engine room and a side hull at the bottom of the engine room area.

3. The ship main engine pre-positioning construction method according to claim 1 is characterized in that: The specific process of the main engine pre-positioning lighting is: lighting the shaft system according to the center line of the hull, confirming the processing allowances of the front and rear end surfaces of the stern tube and the stern bearing, and according to the arrangement of the main engine foot screw holes, determining the center positions of the screw holes at the four top corners of the main engine on the main engine base panel, determining the shaft system length and the position of the hull center line through pre-positioning lighting, and determining the height position of the shaft system center line through shaft system lighting.

4. The ship main engine pre-positioning construction method according to claim 3 is characterized in that: The main engine foot bolt marking is specifically as follows: based on the four screw hole center point positions obtained by pre-positioning the main engine, the main engine base foot screw holes are marked according to the main engine foot hole arrangement, and the screw hole inspection circle is drawn according to the screw hole marking.

5. The ship main engine pre-positioning construction method according to claim 1 is characterized in that: The machining accuracy of the main engine foot screw holes is confirmed by inspection circles.

6. The ship main engine pre-positioning construction method according to claim 1 is characterized in that: The shaft rudder system lighting includes: 1) Check the centerline of the main engine foot screw holes according to the centerline of the hull; 2) Confirm the shafting centerline using the hull centerline and baseline height; 3) Confirm the rudder system centerline and check whether the intersection relationship with the shaft system centerline meets the technical requirements; 4) Use the centerline of the shafting system as the centerline of the stern tube to confirm the position of the machining circle of the stern tube bearing. At the same time, measure the length of the shafting system centerline based on the theoretical data from the rear end screw hole of the main engine to the rear end face of the stern tube to determine the machining amount of the rear end face of the stern tube; 5) Confirm the height of the intermediate bearing base of the shaft system based on the center line of the shaft system.

7. The ship main engine pre-positioning construction method according to claim 1 is characterized in that: The specific process of the host hoisting is: when the shaft system is preset to the shaft state, the host hoisting work is carried out according to the pre-positioned main engine foot screw holes and the shaft system centerline height value confirmed by lighting the shaft system.

8. The ship main engine pre-positioning construction method according to claim 1 is characterized in that: The specific process of boring the stern tube is as follows: the stern tube machining is carried out in parallel with the main engine hoisting, and the stern tube machining is carried out according to the optical data; the stern tube bearing is machined first, and then the front and rear end surfaces of the stern tube are machined.

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