阅读说明：本技术 用于大型船用曲轴红套后的放倒方法 (Method for laying down crankshaft after shrinkage fit for large ship ) 是由 吴凡 马志鸿 姜楠 周焕军 张成佳 沈夏 康艳荣 冯军 于 2019-11-29 设计创作，主要内容包括：本发明提供一种用于大型船用曲轴红套后的放倒方法,包括如下步骤：1、设计制作专用放倒吊具；2、对吊耳及吊耳和吊板连接处进行探伤；3、将起重设备的两根吊带与两个吊耳对应连接；4、安装专用放倒吊具；5、启动起重设备,将大型船用曲轴整体垂直吊起直至其底部高出红套平台；之后将大型船用曲轴作水平位移直至离开平台一定距离；之后降低大型船用曲轴的高度,当大型船用曲轴底部着地后曲轴发生倾斜,继续降低高度直至曲轴完全着地；6、打开挡板拆卸专用放倒吊具。采用上述技术方案,本发明具有吊装作业效率高、安全性好、起吊平稳、对曲轴无损伤等优点。(The invention provides a method for laying down a large-scale marine crankshaft after shrinkage fit, which comprises the following steps: 1. designing and manufacturing a special laying-down lifting appliance; 2. carrying out flaw detection on the lifting lugs and the joints of the lifting lugs and the lifting plates; 3. correspondingly connecting two hanging belts of the hoisting equipment with the two lifting eyes; 4. installing a special laying down hanger; 5. starting the hoisting equipment, and vertically hoisting the whole large marine crankshaft until the bottom of the crankshaft is higher than the red sleeve platform; then horizontally displacing the crankshaft for the large ship until the crankshaft is away from the platform for a certain distance; then reducing the height of the large marine crankshaft, and when the bottom of the large marine crankshaft is grounded, the crankshaft inclines, and continuously reducing the height until the crankshaft is completely grounded; 6. the baffle is opened to disassemble the special laying-down sling. By adopting the technical scheme, the invention has the advantages of high hoisting operation efficiency, good safety, stable hoisting, no damage to the crankshaft and the like.)

1. The laying method for the large marine crankshaft after the red sleeve is adopted is characterized by comprising the following steps of:

designing and manufacturing a special laying-down lifting appliance for a large marine crankshaft; the main body of the special laying-down lifting appliance is a lifting plate formed by a U-shaped metal plate, two end parts of an opening of the lifting plate are respectively hinged with a baffle, and the other ends of the two baffles, which are hinged with the lifting plate, can be detachably connected; the inner side of the hanging plate, facing the bottom of the opening, is also provided with a hoop part with a semi-cylindrical surface, and the hoop part is used for abutting against a main journal of the crankshaft during operation; two lifting lugs are symmetrically arranged on the outer side of the lifting plate;

secondly, carrying out ultrasonic flaw detection and magnetic particle flaw detection on the lifting lugs and the joints of the lifting lugs and the lifting plates;

correspondingly connecting two hanging straps of the hoisting equipment with the two lifting eyes, enabling the hanging straps to rotate relative to the lifting eyes, and enabling the lengths of the two hanging straps to be equal so as to keep the crankshaft in a vertical state during hoisting;

step four, installing a special laying-down lifting appliance; opening the baffle plates, sleeving a special laying lifting appliance at a main journal below a crankshaft lifting side flange plate of a large ship, enabling an adjusting pad to embrace the main journal of the crankshaft, and then closing and connecting the two baffle plates;

step five, starting the hoisting equipment, and vertically hoisting the whole large marine crankshaft until the bottom of the crankshaft is higher than the red sleeve platform; then horizontally displacing the crankshaft for the large ship until the crankshaft is away from the platform for a certain distance; then reducing the height of the large marine crankshaft, and when the bottom of the large marine crankshaft is grounded, the crankshaft inclines, and continuously reducing the height until the crankshaft is completely grounded;

and step six, opening the baffle to disassemble the special laying-down lifting appliance.

2. The method for lowering the crankshaft of the large ship after the crankshaft is sleeved with the red sleeve according to the claim 1, wherein the method comprises the following steps: the special laying lifting appliance further comprises an adjusting pad formed by at least one arched metal strip, the adjusting pad is detachably mounted at the bottom of the inner side of the lifting plate, and the inner side face of the adjusting pad forms the hoop part.

3. The method for lowering the crankshaft of the large ship after the crankshaft is sleeved with the red sleeve according to the claim 2, wherein the method comprises the following steps: on any longitudinal section of the hanging plate, the two baffles and the hinged positions of the hanging plate and the baffles are all positioned on a virtual circle, and the circle center of the virtual circle is concentric with the circle center on the hoop part.

4. The method for lowering the crankshaft of the large ship after the crankshaft is sleeved with the red sleeve according to the claim 3, wherein the method comprises the following steps: on any longitudinal section of the hanging plate, the circle center of the hoop part and the two lifting lugs are located on the same virtual straight line.

5. The method for lowering the crankshaft of the large ship after the crankshaft is sleeved with the red sleeve according to the claim 4, wherein the method comprises the following steps: the two baffles are detachably connected in a bolt type manner; the other end of one baffle plate, which is hinged with the hanging plate, is provided with a mortise and a first pin hole which penetrates through two sides of the mortise; the other end of the other baffle plate, which is hinged with the hanging plate, is provided with a tenon capable of being inserted into the mortise, a second pin hole is formed in the tenon, and a pin is arranged in the first pin hole and the second pin hole in a penetrating mode.

6. The method for lowering the crankshaft of the large ship after the crankshaft is sleeved with the red sleeve according to the claim 5, wherein the method comprises the following steps: and a plurality of connecting counter bores for being bolted to the bottom of the hanging plate groove are uniformly distributed on the adjusting pad.

7. The method for lowering the crankshaft of the large ship after the crankshaft is sleeved with the red sleeve according to the claim 6, wherein the method comprises the following steps: the number of the adjusting pads is multiple, and the radiuses of the inner side surfaces of the adjusting pads are different.

8. The method for lowering the crankshaft of the large ship after the crankshaft is sleeved with the red sleeve according to claim 7, wherein the method comprises the following steps: the lifting lug is a cylinder which is convexly arranged on the outer side of the lifting plate, and the tail end of the cylinder is provided with a flange.

Technical Field

The invention relates to the field of crankshaft machining, in particular to a method for laying down a crankshaft for a large ship after shrinkage fit.

Background

The crankshaft is one of the most important parts in the engine through which all the power of the engine is output, and therefore, the quality of the crankshaft, which is a core component of the diesel engine, is critical to the overall engine life. The following steps are required to be carried out in the process of processing and manufacturing the crankshaft: the method comprises the following steps of crankshaft single part processing, crankshaft shrinkage fit (sleeving a whole crankshaft), crankshaft integral processing, crankshaft flange hole processing and the like.

Wherein the crankshaft shrink fit refers to: because the whole mass of the crankshaft is huge, a semi-combined structure is often adopted, and the main journal and the crank arm are spliced together through a shrink-fit process. The red sleeve is that the crank arm is heated to a certain temperature to expand the aperture, then the main journal at normal temperature is sleeved in the hole, and after cooling, the clamping force is generated due to the interference fit between the main journal and the crank arm hole, so that the combined body can bear the required load. The common crankshaft shrink-fit step also comprises; fixing, shrink-fitting, pouring, pit discharging and the like. Because the weight of the crankshaft is large, the crankshaft needs to be laid down firstly after shrinkage fit in order to meet the requirement that the crankshaft is out of a pit.

At present, a special lifting appliance is not arranged in the crankshaft falling step, a general vertical lifting appliance is generally adopted, the crankshaft is inclined by external force assistance after being lifted out of the red jacket platform, the operation steps are increased, and the crankshaft is likely to be damaged in the process due to the large mass and high surface precision requirement of the crankshaft, so that the operation difficulty is greatly increased.

Disclosure of Invention

The invention aims to provide a method for laying down a large marine crankshaft after shrinkage fit, which has high efficiency, good safety, stable lifting and no damage to the crankshaft, and aims to overcome the defects of the prior art.

In order to achieve the purpose, the invention provides a method for laying a large marine crankshaft after red sleeve, wherein the large marine crankshaft is erected in a red sleeve platform, and the method comprises the following steps:

the laying method for the large marine crankshaft after the red sleeve is adopted is characterized by comprising the following steps of:

designing and manufacturing a special laying-down lifting appliance for a large marine crankshaft; the main body of the special laying-down lifting appliance is a lifting plate formed by a U-shaped metal plate, two end parts of an opening of the lifting plate are respectively hinged with a baffle, and the other ends of the two baffles, which are hinged with the lifting plate, can be detachably connected; the inner side of the hanging plate, facing the bottom of the opening, is also provided with a hoop part with a semi-cylindrical surface, and the hoop part is used for abutting against a main journal of the crankshaft during operation; two lifting lugs are symmetrically arranged on the outer side of the lifting plate;

secondly, carrying out ultrasonic flaw detection and magnetic particle flaw detection on the lifting lugs and the joints of the lifting lugs and the lifting plates;

correspondingly connecting two hanging straps of the hoisting equipment with the two lifting eyes, enabling the hanging straps to rotate relative to the lifting eyes, and enabling the lengths of the two hanging straps to be equal so as to keep the crankshaft in a vertical state during hoisting;

step four, installing a special laying-down lifting appliance; opening the baffle plates, sleeving a special laying lifting appliance at a main journal below a crankshaft lifting side flange plate of a large ship, enabling an adjusting pad to embrace the main journal of the crankshaft, and then closing and connecting the two baffle plates;

step five, starting the hoisting equipment, and vertically hoisting the whole large marine crankshaft until the bottom of the crankshaft is higher than the red sleeve platform; then horizontally displacing the crankshaft for the large ship until the crankshaft is away from the platform for a certain distance; then reducing the height of the large marine crankshaft, and when the bottom of the large marine crankshaft is grounded, the crankshaft inclines, and continuously reducing the height until the crankshaft is completely grounded;

and step six, opening the baffle to disassemble the special laying-down lifting appliance.

The special laying lifting appliance further comprises an adjusting pad formed by at least one arched metal strip, the adjusting pad is detachably mounted at the bottom of the inner side of the lifting plate, and the inner side face of the adjusting pad forms the hoop part.

On any longitudinal section of the hanging plate, the two baffles and the hinged positions of the hanging plate and the baffles are all positioned on a virtual circle, and the circle center of the virtual circle is concentric with the circle center on the hoop part.

On any longitudinal section of the hanging plate, the circle center of the hoop part and the two lifting lugs are located on the same virtual straight line.

The two baffles are detachably connected in a bolt type manner; the other end of one baffle plate, which is hinged with the hanging plate, is provided with a mortise and a first pin hole which penetrates through two sides of the mortise; the other end of the other baffle plate, which is hinged with the hanging plate, is provided with a tenon capable of being inserted into the mortise, a second pin hole is formed in the tenon, and a pin is arranged in the first pin hole and the second pin hole in a penetrating mode.

And a plurality of connecting counter bores for being bolted to the bottom of the hanging plate groove are uniformly distributed on the adjusting pad.

The number of the adjusting pads is multiple, and the radiuses of the inner side surfaces of the adjusting pads are different.

The lifting lug is a cylinder which is convexly arranged on the outer side of the lifting plate, and the tail end of the cylinder is provided with a flange.

By adopting the technical scheme, the invention has the advantages of high hoisting operation efficiency, good safety, stable hoisting, no damage to the crankshaft and the like.

Drawings

The above features and advantages of the present invention will become more apparent and readily appreciated from the following description of the exemplary embodiments thereof taken in conjunction with the accompanying drawings.

FIG. 1 is a perspective view of a special laying down spreader according to an embodiment of the invention;

FIG. 2 is a structural diagram of a special-purpose laying down spreader according to an embodiment of the invention;

FIG. 3 is a structural diagram of a main body of the special-purpose laying down spreader in the embodiment of the invention;

FIG. 4 is a schematic diagram illustrating the hoisting of the special-purpose lowering sling according to the embodiment of the present invention;

fig. 5 is a structural diagram of an adjusting pad of the special-purpose laying down spreader in the embodiment of the invention.

Detailed Description

The invention is described in further detail below with reference to the attached drawing figures to facilitate understanding by those skilled in the art:

referring to fig. 1 to 5, the method for lowering the crankshaft after shrink-wrapping for the large ship in the embodiment of the invention mainly uses a special lowering hanger for hoisting the crankshaft after the shrink-wrapping operation is completed.

The main body of the special laying lifting appliance is a lifting plate 1, and the lifting plate 1 is composed of a U-shaped steel plate. For convenience of presentation, in the present invention: the two tail ends of the opening of the hanging plate 1 are collectively called as the two ends of the hanging plate 1; the U-shaped side surface facing the opening between the two ends is called the inner side of the hanging plate 1, and the bottom facing the opening on the inner side is called the groove bottom; the side of the U between the two ends that is open to the outside is referred to as the hanger plate 1; the side between the inner side and the outer side is a front and a back side.

Referring to fig. 3, two lifting lugs 2 are symmetrically arranged on the outer side of the lifting plate 1. In this embodiment, the lifting lug 2 is a cylinder protruding from the outer side of the hanging plate 1, and a flange is provided at the end of the cylinder. The corresponding position of the outside of the hanger plate 1 is provided with an orifice 11, and the lifting lug 2 is arranged in the orifice. The lifting lug 2 is used as a lifting stress piece, and is required to be subjected to ultrasonic flaw detection and magnetic powder flaw detection before being used every time

Two ends of the hanging plate 1 form a fork 12, the fork 12 is hinged with a baffle 3, and the other ends of the two baffles 3 which are hinged with the hanging plate 1 can be detachably connected. In this embodiment, the detachable connection structure of the two baffles 3 is a plug-type connection; the other end of one baffle 3, which is hinged with the hanging plate 1, is provided with a mortise and a first pin hole which penetrates through two sides of the mortise; the other end of the other baffle 3, which is hinged with the hanger plate 1, is provided with a tenon capable of being inserted into the mortise, a second pin hole is formed on the tenon, and a pin 4 penetrates through the first pin hole and the second pin hole. The purpose of setting up baffle 3 is in order to prevent to lift by crane the drunkenness all around of hanger plate 1, can guarantee safe and stable when making to lift by crane.

The inner side of the hanging plate 1 is detachably provided with an adjusting pad 5, and the adjusting pad 5 is arranged to eliminate the gap between the special laying-down hanger and the crankshaft main journal, so that the safety and stability are ensured during lifting. Therefore, the inner side surface of the adjusting pad 5 opposite to the opening of the hanging plate 1 is provided with a semi-cylindrical surface part which is used for being abutted against the main journal of the crankshaft during operation, and the radian of the semi-cylindrical surface part is matched with the shape of the main journal of the crankshaft to be hoisted. When the special laying-down lifting appliance is installed, the baffle plates 3 are opened, the special laying-down lifting appliance is sleeved at the main journal 72 below the lifting side flange plate 71 of the large-scale marine crankshaft 7, the adjusting pad is made to embrace the main journal 72 of the crankshaft 7, and then the two baffle plates 3 are closed and connected.

In order to make the hoist and mount steady and easy operation, this special use is fallen adjustment pad of hoist and is filled up and have following structural feature:

1. on any longitudinal section of the hanger plate 1: the hanger plate 1, the two flaps 3 and the hinging of the hanger plate 1 and the flaps 3 all lie on an imaginary circle 6 (see figure 2); the center of the virtual circle is concentric with the inner side surface of the adjusting pad 5, so that the axle center of the crankshaft during hoisting operation is defined.

2. On any longitudinal section of the hanger plate 1, the circle center of the inner side surface of the adjusting pad 5 and the two lifting lugs 2 are positioned on the same virtual straight line, and therefore during lifting operation, the connecting line of the two lifting lugs 2 penetrates through the axis of the crankshaft.

Through the arrangement, stable lifting and no damage to the crankshaft during lifting operation are guaranteed.

In a further embodiment, the special laying spreader may be provided with a plurality of adjusting pads 5, and a plurality of connecting counterbores 51 for bolting to the bottom of the main body groove are uniformly distributed on the adjusting pads 5. This allows a detachable connection to the hanger plate 1, so that different crankshafts can be adapted by replacing the adjusting mat 5.

With reference to the special lying spreader, the following describes in detail the operation steps of the lying method for the large marine crankshaft after shrinkage fit in the present embodiment:

designing and manufacturing the special laying lifting appliance;

secondly, carrying out ultrasonic flaw detection and magnetic particle flaw detection on the lifting lugs and the joints of the lifting lugs and the lifting plates;

correspondingly connecting two hanging straps of the hoisting equipment with the two lifting eyes, enabling the hanging straps to rotate relative to the lifting eyes, and enabling the lengths of the two hanging straps to be equal so as to keep the crankshaft in a vertical state during hoisting;

step four, installing a special laying-down lifting appliance; opening the baffle plates, sleeving a special laying lifting appliance at a main journal below a crankshaft lifting side flange plate of a large ship, enabling an adjusting pad to embrace the main journal of the crankshaft, and then closing and connecting the two baffle plates;

step five, starting the hoisting equipment, and vertically hoisting the whole large marine crankshaft until the bottom of the crankshaft is higher than the red sleeve platform; then horizontally displacing the crankshaft for the large ship until the crankshaft is away from the platform for a certain distance; then reducing the height of the large marine crankshaft, and when the bottom of the large marine crankshaft is grounded, the crankshaft inclines, and continuously reducing the height until the crankshaft is completely grounded;

and step six, opening the baffle to disassemble the special laying-down lifting appliance.

Although the present invention is described in detail with reference to the embodiments, it should be understood by those skilled in the art that the above embodiments are only one of the preferred embodiments of the present invention, and not all embodiments can be enumerated herein for the sake of brevity, and any embodiment that can embody the claims of the present invention is within the protection scope of the present invention.