CN-122009429-A - Hoisting and turning-over method for non-welding lifting lug of large steel structure

Abstract

A method for lifting and turning over the non-welded lifting lugs of large steel structure includes such steps as numerical control or manual cutting permanent holes on the vertical plate or T-shaped web plate of steel structure, matching the positions and numbers of lifting points of crane, and welding permanent reinforcing plates around said holes for reinforcing. The size of the opening is required to meet the assembly requirement of the pin shaft of the turning-over connecting device, and the specification and the size of the reinforcing plate are required to meet the assembly of the hoisting turning-over device and the requirement of safety specifications. The inside of the connecting plate is designed with double bevel edges, the angle of each bevel edge is 20 degrees, when the working condition of tire lifting and turning over is 180 degrees after the tool is permanently perforated and connected with the structure, the right bevel edge is in line contact with the free edge of the T-shaped beam, so that the pressure of line load is conveniently born, and the inclination angle of the double half-piece structure of the device and the horizontal plane is 20 degrees, so that the whole stress condition of the tool is optimized. Only the pin shaft is contacted with the open hole in the process of turning over to 90 degrees.

Inventors

• LI JING
• WANG YINGANG
• LI LU
• HUANG LUMING
• HUANG TIANYING
• Wang jining
• LI SHENGKAI
• LUO DA
• HUANG YANFENG

Assignees

• 大连船舶重工集团有限公司

Dates

Publication Date

20260512

Application Date

20260401

Claims (8)

1. 1. A hoisting and turning method for a large steel structure non-welding lifting lug is characterized in that a main turning hole and an auxiliary turning hole are respectively formed at two ends of a ship sub-section, a main turning hanging point and an auxiliary turning hanging point are formed, the main turning hole and the auxiliary turning hole are permanent holes, the main turning hole is formed by punching on two adjacent T-shaped beam webs at one end of the sub-section, and two adjacent main turning holes are in a pair and are two pairs; the auxiliary turning holes are formed in the T-shaped beam web at the other end of the subsection, and are provided with two auxiliary turning holes, and a space is reserved between the two auxiliary turning holes; Reinforcing plates are welded on the main turning holes and the auxiliary turning holes, and the diameters of the holes of the reinforcing plates are larger than those of the main turning holes and the auxiliary turning holes; during hoisting, hoisting clamps are fixed on the main turning hole and the auxiliary turning hole, each hoisting clamp comprises two plates with the same structure, a connecting block is fixed at one end of each plate and between the two plates, the other ends of the two plates clamp the main turning hole or the auxiliary turning hole and are hinged with the main turning hole or the auxiliary turning hole through a pin shaft, and one side, close to a T-shaped beam web, of each connecting block is provided with an inclined part; one side of the hoisting clamp with the connecting block is hinged with the crane shackle; the specific turning-over process is as follows: S1, under the working conditions of lifting and tire lifting, maintaining the ship sub-section parallel to a horizontal plane, simultaneously bearing force on a main turning over lifting point and an auxiliary turning over lifting point, and enabling a crane to horizontally hoist the ship sub-section from a tire frame to a turning over site, and preparing to turn over after falling to the ground; S2, separating the hoisting clamp from the auxiliary turning hole, connecting the hoisting clamp to the main turning hole, connecting the hoisting clamp to a crane through a steel wire rope, slowly lifting the crane at one end of the main turning hole upwards, forming a rotating shaft at the other end of the section all the time, and starting turning the section; S3, when the main turning over is turned over to 20 degrees, the beveling of the connecting block is in line contact with the edge of the T-shaped beam web, at the moment, the bearing connecting plate on the main turning over hole is about to be separated from contact with the edge of the T-shaped beam web, the main turning over hanging point is continuously lifted upwards, and the other end of the segment is kept to be turned over by grounding; S4, finishing a segmented landing rolling link when turning over to 90 degrees, lifting the main turning over lifting point to lift the segment 500mm away from the ground, and connecting the crane with the auxiliary turning over hole at the lower end of the segment through the lifting clamp; s5, connecting the auxiliary turning device, and then performing combined operation of the main turning and auxiliary turning lifting hooks to turn the segments to 180 degrees, wherein the bevels of all connecting blocks are in line contact with the edges of the web plates of the T-shaped beam; S6, finishing the assembly of the semi-solid and the outer bottom plate or the outer shell plate, starting loosening force on the main turning lifting point and the auxiliary turning lifting point after sealing welding, and dismantling and recovering the hoisting clamp for repeated use.
2. 2. The lifting and turning method for the welding-free lifting lug of the large steel structure, which is disclosed in claim 1, is characterized in that the diameters of the openings of the main turning hole and the auxiliary turning hole are 3-4 mm larger than the diameter of the pin shaft.
3. 3. The method for lifting and turning over a large steel structure non-welded lifting lug according to claim 1, wherein the ship sub-section is a sub-section of a ship double-bottom or double-shell section.
4. 4. The method for lifting and turning over a large steel structure non-welding lifting lug according to claim 1, wherein the slanting is arranged from the central axis of the connecting block to two sides.
5. 5. The method for lifting and turning over a large steel structure non-welded lifting lug according to claim 1, wherein the bearing connecting plate is connected with a shackle of a crane hook.
6. 6. The method for hoisting and turning over the welding-free lifting lug of the large steel structure, which is disclosed in claim 1, is characterized in that two ends of the plate are arc-shaped, the outer sides of the connecting blocks are arc-shaped, and the arc-shaped radius of the connecting blocks is larger than that of the plate.
7. 7. The method for lifting and turning over a large steel structure non-welding lifting lug according to claim 1, wherein the weight of the ship sub-section is less than 80t.
8. 8. The method for lifting and turning a large steel structure non-welding lifting lug according to claim 1, wherein the angle of inclination is 20 degrees.

Description

Hoisting and turning-over method for non-welding lifting lug of large steel structure Technical Field The invention belongs to the field of marine ship construction and design, and particularly relates to a hoisting and turning-over method for a large steel structure non-welding lifting lug. Background The semi-solid structure is a subsection of a ship double bottom or double shell subsection, and is formed by welding a T-shaped beam after splicing an inner bottom plate or an inner shell plate. The semi-solid segments are assembled with the outsole or skin after turning over using the crane to form the complete segments. In order to realize the integral turning of the semi-three-dimensional large steel structure, a method is generally adopted in which a plurality of special lifting lugs for turning are welded on the structure, and after the turning is finished, the lifting lugs are cut off and repair work of a base metal and the structure is completed. The traditional lifting and turning-over process for installing lifting lugs has the following defects: 1. The single turning over is required to be subjected to the complex procedures of lifting lug and temporary reinforcement, welding, post-welding flaw detection, lifting turning over, cutting/gouging, base material polishing, plate hole repairing and the like. The time for occupying the assembly line position is longer, and the whole construction beat of the assembly line is dragged slowly. 2. The cost is high, the number of C-shaped lifting lugs used for semi-three-dimensional turning over and temporary reinforcement thereof exceeds 8500, the repeated utilization rate of the lifting lugs is less than 10%, and the material cost is about 200 ten thousand yuan per year. Meanwhile, the labor cost for putting the lifting lug into the assembly welding and the cutting repair is huge, and the time length of manual operation in the whole year is counted to exceed 32000 hours. 3. Potential quality hazards include that the welding lifting lug has the risk of damaging parent metal, and the quality risks of damaging an original groove, a T-shaped Liang Duanche and the like after cutting are also present. 4. The labor intensity is high, the operations of carrying, welding, cutting and polishing are required for many times, the heavy burden is caused by the complicated process and heavy physical labor, and meanwhile, the potential safety hazard is increased. Disclosure of Invention In order to solve the problems, the invention provides a hoisting and turning method for a large steel structure non-welding lifting lug, which adopts the following technical scheme: a hoisting and turning method for a welding-free lifting lug of a large steel structure comprises the steps that a main turning hole and an auxiliary turning hole are respectively formed in two ends of a ship sub-section, so that a main turning hanging point and an auxiliary turning hanging point are formed, the main turning hole and the auxiliary turning hole are permanent holes, the main turning hole is formed in two adjacent T-shaped beam webs at one end of the sub-section, two adjacent main turning holes are in a pair, and two pairs are formed. The auxiliary turning holes are formed in the T-shaped beam web at the other end of the subsection, two auxiliary turning holes are formed, and a space exists between the two auxiliary turning holes. The distance between the two pairs of main turning holes is larger than that between the two auxiliary turning holes. Reinforcing plates are welded on the main turning holes and the auxiliary turning holes, and the diameters of the holes of the reinforcing plates are larger than those of the main turning holes and the auxiliary turning holes. During hoisting, the main turning hole and the auxiliary turning hole are fixedly provided with hoisting clamps, each hoisting clamp comprises two plates with the same structure, a connecting block is fixed between one end of each plate and each plate, the other end of each plate clamps the main turning hole or the auxiliary turning hole, the main turning hole or the auxiliary turning hole is hinged with the corresponding pin shaft, and one side, close to the T-shaped beam web, of each connecting block is provided with an inclined structure. The side of the lifting clamp with the connecting block is hinged with the crane shackle. The specific turning-over process is as follows: S1, under the working conditions of lifting and tire lifting, the ship sub-section is kept parallel to the horizontal plane, the main turning over and auxiliary turning over lifting points are stressed simultaneously, the crane horizontally lifts the ship sub-section from the tire frame to the turning over site, and the ship sub-section is ready to turn over after falling to the hook for landing. S2, separating the hoisting clamp from the auxiliary turning hole, connecting the hoisting clamp to the main turning hole, connecting the hoisting clamp to a crane thr