A double-beam eccentric lifting method for hoisting a finishing mill unit

Abstract

The present invention is a double-beam eccentric lifting method, which includes two existing overhead cranes and a double-beam lifting beam. The method further comprises the following steps: lying the rolling mill stand horizontally on the supporting steel stools, and keeping the stand placed at an inclination of about 10° with the horizontal direction; sleeving the stand onto the double-beam lifting beam, firmly fixing it to the H-shaped steel, and then the two overhead cranes start to slowly lift synchronously; when the stand is lifted to the expected height, hoist the stand to the installation position and slowly place it in position; after the stand is in place, finally tighten the anchor bolts according to the torque requirements, and at this time the installation of the stand is completed. Compared with the traditional rotary balance method, which has the defects that a large number of components need to be assembled and reinforced on site and the sliding process is complex and slow, the double-beam eccentric lifting method of the present invention fixes, turns over and places the stand in one go through the precise design and perfect cooperation of the overhead crane and the lifting beam; greatly improving the lifting efficiency. At the same time, the double-beam lifting beam can be reused in future similar projects, which is both economical and environmentally friendly.

Description

Technical Field

[0001] The present invention relates to the technical field of installation of electromechanical equipment, and specifically to a double-beam eccentric lifting method for hoisting a finishing mill unit. Background Art

[0002] In metallurgical engineering projects, the installation of equipment on the rolling production line mostly adopts closed construction. Due to the overweight of the rolling mill housing and its extremely large external dimensions, the single-crane lifting capacity in the workshop far cannot meet the hoisting requirements of the rolling mill housing. During the implementation of installing the rolling mill housing using the traditional rotary balance method, as the external dimensions of the equipment are large, the jacking (lowering) stroke is also increased. It is found that during the jacking and lowering processes of the housing, the stability is difficult to control. The larger the jacking amplitude, the worse the stability, and there are adverse factors such as potential safety hazards. Since the rotary balance method has a complex process, requires a large number of supporting fittings, and requires a long pre-assembly time, it is very time-consuming and laborious. Summary of the Invention

[0003] In order to solve the defects that in the conventional rotary balance method, the pre-assembly is cumbersome, the stability is difficult to control, and there are certain potential safety hazards during use, a method is proposed in which two overhead cranes in the main rolling bay of the workshop cooperate to adopt a set of double-beam lifting beam synchronous lifting method to install the rolling mill housing; in this way, not only the work efficiency of equipment installation is improved, but also the labor intensity and safety risks of operators are reduced.

[0004] To achieve the above object, the present invention is implemented as follows:

[0005] A double-beam eccentric lifting method for hoisting a finishing mill unit includes two existing overhead cranes (No. 1 and No. 2), and also includes a double-beam lifting beam (No. 3). The double-beam lifting beam (No. 3) includes two symmetrically arranged box girders (No. 5 and No. 6), lifting lugs (No. 7) located at both ends of the two box girders (No. 5 and No. 6), pins (No. 8) located at both ends of the two box girders (No. 5 and No. 6), H-shaped short cross beams (No. 9) respectively connected to both ends of the two box girders (No. 5 and No. 6) and connecting bolts (No. 10), and also includes the following steps:

[0006] Step 1: Confirm the distance between the No. 1 overhead crane and the No. 2 overhead crane. The distance between the cranes must meet the installation requirements for the opening dimension between the lifting lugs (No. 7) at both ends of the lifting beam.

[0007] Step 2: Unload the rolling mill housing through the two overhead cranes (No. 1 and No. 2) with a balance beam.

[0008] Step 3: Lay the rolling mill housing horizontally on 6 horizontally arranged support steel stools, and keep the housing placed in an inclined state of about 10° with the horizontal direction.

[0009] Step 4: Assemble the double-beam lifting beam (3#) on the ground and prepare the auxiliary parts for the hoisting work;

[0010] Step 5: Lift the rolling mill stand from three places in the middle with steel stools. The steel stools are distributed on both sides of the stand window, and sleepers are laid on the steel stools. One more sleeper is padded on the top of the stand, so that the stand forms an angle of about 10° with the horizontal plane of the top plate when placed;

[0011] Step 6: Calculation of the eccentricity of the stand: Since the finishing mill unit is usually in the form of multi-stand continuous rolling, there is a certain center distance between the rolling mill stands. If all the stands are hoisted by fixing them in the middle of the double-beam lifting beam, when hoisting the second group of stands, since the distance from the center of the stand to the end of the lifting beam is greater than the distance between the stands, there will be a collision between the lifting beam and the already installed stand, and the second group of stands cannot be in place. In order to meet the installation of multiple stands, eccentric hoisting needs to be carried out and the eccentricity needs to be calculated. The hoisting after eccentricity must ensure that the double-beam lifting beam (3#) does not interfere with the stand when hoisting the lower stand. Therefore, the eccentricity needs to be calculated according to the number of stands, the width and height of the stand, so as to meet the minimum space requirement for hoisting the next stand;

[0012] Step 7: Set the stand on the double-beam lifting beam (3#). After firmly fixing it with the H-shaped steel, the two overhead cranes (1#, 2#) start to slowly lift synchronously. When the stand is in an upright state, after determining that the braking performance of the overhead crane and the safety of each connection point are reliable, repeat it twice. Finally, after confirming that the overhead crane, the stand, the lifting appliance and each connection point are all okay, lift synchronously;

[0013] Step 8: When the stand is lifted to the expected height, the two overhead cranes coordinate with each other, and the trolleys run synchronously. After hoisting the stand to the installation position, slowly place it in place;

[0014] Step 9: After the stand is safely in place, pre-fix it with anchor bolts; when the stand is finally leveled and aligned, tighten the anchor bolts according to the torque requirements. At this time, the installation of the stand is completed.

[0015] The double-beam eccentric lifting method proposed by the present invention makes full use of the effective combination of the existing overhead crane and the lifting beam in the factory workshop, and adopts an economical, effective and safe hoisting method. Compared with the traditional rotary balance method, which requires a large number of components to be assembled and reinforced on site and the sliding process is complex and slow, this method has better operability and higher safety. Through the precise design and perfect cooperation of the overhead crane and the lifting beam, the stand is fixed, turned over and placed in place in one go. Greatly improve the hoisting efficiency. At the same time, the double-beam lifting beam can be reused in future similar projects, which is both economical and environmentally friendly. Brief Description of the Drawings

[0016] Figure 1It is a structural schematic diagram of a double - beam shoulder pole beam.

[0017] Figure 2 It is a schematic diagram of the placement of the frame in the present invention.

[0018] Figure 3 It is a schematic diagram of the hoisting state of the rolling mill in the present invention. Specific implementation manners

[0019] The present invention will be further described below through specific embodiments.

[0020] A double - beam eccentric lifting method for hoisting a finishing rolling mill unit includes two existing overhead traveling cranes (No. 1 and No. 2), and also includes a double - beam shoulder pole beam (No. 3). As Figure 1 shown, the double - beam shoulder pole beam (No. 3) includes two symmetrically arranged box girders (No. 5 and No. 6), lifting lugs (No. 7) located at both ends of the two box girders (No. 5 and No. 6), pins (No. 8) located at both ends of the two box girders (No. 5 and No. 6), H - shaped short cross - beams (No. 9) respectively connected to the two ends of the two box girders (No. 5 and No. 6) and connecting bolts (No. 10). The method also includes the following steps:

[0021] Step 1: Confirm the distance between the No. 1 overhead traveling crane and the No. 2 overhead traveling crane. The distance between the traveling cranes must meet the installation requirements of the opening dimension between the lifting lugs (No. 7) at both ends of the shoulder pole beam.

[0022] Step 2: Unload the rolling mill frame through the two overhead traveling cranes (No. 1 and No. 2) with a balance beam.

[0023] Step 3: Lay the rolling mill frame horizontally on 6 horizontally arranged support steel stools, and keep the frame placed at an inclined state of about 10° with the horizontal direction, as Figure 2 shown.

[0024] Step 4: Assemble the double - beam shoulder pole beam (No. 3) on the ground and prepare the auxiliary parts for the hoisting work.

[0025] Step 5: Pad the rolling mill frame from three places in the middle with steel stools. The steel stools are distributed on both sides of the frame window, and sleepers are laid on the steel stools. One more sleeper is padded on the top of the frame, so that the frame forms an angle of about 10° with the horizontal plane of the top plate.

[0026] Step 6: Calculate the eccentricity of the frame: The hoisting after eccentricity must ensure that the double - beam shoulder pole beam (No. 3) does not interfere with the frame when hoisting the lower rolling mill frame. Therefore, it is necessary to calculate the eccentricity according to the number of frames, the width and height of the frame, so as to meet the minimum space requirements for hoisting the next frame.

[0027] Step 7: Set the frame onto the double - beam shoulder pole beam (No. 3), and firmly fix it with the H - shaped steel. As Figure 3, two overhead cranes (1# and 2#) start to slowly lift synchronously. After the frame is in an upright state, after confirming the braking performance of the overhead cranes and the safety and reliability of each connection point, repeat twice. Finally, after confirming that the overhead cranes, the frame, the lifting appliances and each connection point are all okay, lift synchronously;

[0028] Step 8: After the frame is lifted to the expected height, the two overhead cranes coordinate with each other, and the trolley runs synchronously. After the frame is hoisted to the installation position, slowly place it in place;

[0029] Step 9: After the frame is safely placed in place, pre-fix it with anchor bolts; when the frame is finally leveled and aligned, tighten the anchor bolts according to the torque requirements. At this time, the installation of the frame is completed.

Claims

1. A double-beam eccentric lifting method for the hoisting of a finishing mill unit, comprising two existing overhead cranes (No. 1 and No. 2), characterized in that: It also includes a double-beam shoulder pole beam (3#), and the double-beam shoulder pole beam (3#) includes two symmetrically arranged box girders (5#, 6#), lifting lugs (7#) located at both ends of the two box girders (5#, 6#), dowel pins (8#) located at both ends of the two box girders (5#, 6#), an H-shaped short cross beam (9#) with both ends respectively connected to the two box girders (5#, 6#), and connecting bolts (10#). It also includes the following steps: Step 1: Confirm the distance between the No. 1 crane and the No. 2 crane. The distance between the cranes must meet the installation requirements for the opening dimension between the lifting lugs (7#) at both ends of the shoulder pole beam; Step 2: Use two cranes (No. 1 and No. 2) with a balance beam to unload the rolling mill stand; Step 3: Lay the rolling mill stand horizontally on 6 horizontally arranged supporting steel stools, and keep the stand placed in a state of about 10° inclination with the horizontal direction; Step 4: Assemble the double-beam shoulder pole beam (3#) on the ground and prepare the auxiliary parts for the hoisting work; Step 5: Pad the rolling mill stand from three places in the middle with steel stools. The steel stools are distributed on both sides of the stand window, and sleepers are laid on the steel stools. One more sleeper is padded on the top of the stand, so that the stand forms an angle of about 10° with the horizontal plane of the top plate when placed; Step 6: Calculate the eccentricity of the stand: The hoisting after eccentricity must ensure that the double-beam shoulder pole beam (3#) does not interfere with the stand when hoisting the lower stand. Therefore, it is necessary to calculate the eccentricity according to the number of stands, the width and height of the stand, so as to meet the minimum space requirement for hoisting the next stand; Step 7: Set the stand into the double-beam shoulder pole beam (3#). After firmly fixing it with the H-shaped steel, the two cranes (No. 1 and No. 2) start to slowly lift synchronously. When the stand is in an upright state, after determining that the braking performance of the cranes and the safety of each connection point are reliable, repeat it twice. Finally, after confirming that the cranes, the stand, the lifting appliances and each connection point are all okay, lift synchronously; Step 8: When the stand is lifted to the expected height, the two cranes coordinate with each other, and the trolleys run synchronously. After the stand is hoisted to the installation position, slowly place it in place; Step 9: After the stand is safely placed in place, pre-fix it with anchor bolts; When the stand is finally leveled and aligned, then tighten the anchor bolts finally according to the torque requirements. At this time, the installation of the stand is completed.

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