On-site hoisting and replacing method for crankshaft of fixed-width side press of hot rolling production line

Abstract

The invention discloses a hot rolling production line fixed-width side press crankshaft on-site hoisting and replacing method, which comprises the following steps of: firstly, disassembling related accessories of a crankshaft, and retaining the crankshaft by adopting a lever block; manufacturing a lifting appliance comprising a lifting beam, an upper lifting lug and a lower lifting lug; the crane main hook is connected with the shackle of the upper lifting lug through a sling, the shackle of the lower lifting lug hooks the 30T hoist, the 30T hoist at the inner side lifting point is used for retaining the crankshaft, the lever hoist is dismounted, the crane moves the crankshaft, and when a rope at the inner side lifting point abuts against a girder of a rolling mill housing, a rope of the 30T hoist at the outer side lifting point is moved to the outer side of the girder of the rolling mill housing; a 30T hoist at the outer side hoisting point is adopted to hold the crankshaft, the rope at the inner side hoisting point is dismounted, and the crane continues to move the crankshaft, so that the crankshaft is pulled out and hoisted away from the rolling mill housing; and the rolling mill housing is cleaned and ground, reverse hoisting and mounting are carried out according to the steps, and crankshaft replacement is completed. The method simplifies operation procedures, reduces cost and period, and ensures normal operation of a hot rolling production line.

Description

Technical Field

[0001] The present invention relates to the technical field of metallurgical equipment maintenance, and in particular to a method for on-site lifting and replacement of a crankshaft of a fixed-width side press of a hot rolling production line. Background Art

[0002] The fixed width side press is a key equipment on the hot rolling production line. It is the first rolling process for efficient side pressing of the steel billet coming out of the heating furnace. It is directly related to the normal production of the entire production line and the quality of the product. The design characteristics of the fixed width side press are that there is only an intermittent side pressing mode, no continuous side pressing mode, the main transmission is on the side, which is easy to maintain, the moving parts are heavy, and the related parts are easy to damage and wear.

[0003] The crankshaft of the fixed width side press (weighing about 46 tons) is fixed to the mill arch in a horizontal form. How to quickly and efficiently replace the crankshaft assembly has become a difficult point in maintenance. In the past, the maintenance process usually involves first disassembling the inner and outer blocks of the crankshaft and lifting them away, then hoisting a special maintenance platform, using the maintenance platform to support the crankshaft with a bracket, removing the semi-harf seat of the crankshaft bearing seat, and finally lifting the crankshaft away. The crankshaft needs to be rotated during the lifting process, and then lifted from the middle of the beam of the mill arch. The entire process requires 10 days of shutdown. Therefore, the crankshaft replacement and lifting operation process is cumbersome and complicated, which increases the cost and cycle of equipment maintenance operations, reduces operating efficiency, and seriously affects the normal operation of the hot rolling production line. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method for on-site lifting and replacement of the crankshaft of a fixed-width side press of a hot rolling production line. The method overcomes the defects of traditional crankshaft lifting operations, solves the problem of on-site replacement and lifting of the crankshaft, simplifies the operating procedures, reduces costs and cycles, and ensures the normal operation of the hot rolling production line.

[0005] In order to solve the above technical problems, the on-site lifting and replacement method of the crankshaft of the fixed-width side press of the hot rolling production line of the present invention comprises the following steps: Step 1: Remove the inner and outer blocks of the crankshaft and move them horizontally to the anti-warping roller frame side of the hot rolling production line; Step 2: Remove the connecting arm and crankshaft takeover bolts that fix the crankshaft; Step 3: Remove the pipeline support and walkway platform on the entrance operation side; Step 4: Use a hand hoist to hold the crankshaft. When the half-haft seat of the crankshaft bearing seat is suspended by a crane, remove the fixing bolts of the half-haft seat by electric heating and lift the half-haft seat away from the bearing seat. Step 5: Make a sling, including a sling beam, upper sling ears arranged on the top surfaces of both ends of the sling beam, and four lower sling ears arranged at intervals on the bottom surface of the sling beam, wherein the two middle lower sling ears constitute the inner sling points, and the two outer lower sling ears constitute the outer sling points, and the upper sling ears and the lower sling ears are respectively provided with shackles; Step 6. The main hook of the crane is connected to the shackle of the upper lifting eye through a sling, and 30T hoists are hooked on the shackles of the four lower lifting eyes respectively. The crane is driven to the top of the crankshaft, and the 30T hoist of the inner lifting point is used to secure the crankshaft. The hand hoist is removed and the crane is directed to move the crankshaft. When the rope of the inner lifting point approaches the beam of the rolling mill arch, the 30T hoist rope of the outer lifting point is moved to the outer side of the rolling mill arch beam, and the 30T hoist of the outer lifting point is used to secure the crankshaft. The rope of the inner lifting point is removed, and the crane continues to move the crankshaft. By moving the lifting point on the lifting beam, the crankshaft is pulled out and lifted from the rolling mill arch. Step 7: Clean and grind the rolling mill arch, lift and install it in reverse according to the above steps to complete the crankshaft replacement.

[0006] Furthermore, the shackles provided on the upper lifting eye and the lower lifting eye are bow-shaped shackles. Since the on-site lifting and replacement method for the fixed-width side press of the hot rolling production line of the present invention adopts the above-mentioned technical scheme, that is, the method first disassembles the inner and outer blocks, connecting arms, crankshaft hand bolts, and the entrance operation side pipeline bracket and the walkway platform of the crankshaft; uses a hand hoist to hold the crankshaft and lift it off the semi-half seat of the crankshaft bearing seat; makes a lifting device including a lifting beam, an upper lifting eye and a lower lifting eye; the main hook of the crane is connected to the shackle of the upper lifting eye through a sling, and the shackle of the lower lifting eye is respectively hooked with a 30T hoist, and the inner side is used to lift the crankshaft. The 30T hoist at the lifting point holds the crankshaft, the hand hoist is removed, and the crane moves the crankshaft. When the rope of the inner lifting point approaches the beam of the rolling mill arch, the rope of the 30T hoist at the outer lifting point is moved to the outside of the beam of the rolling mill arch, and the 30T hoist at the outer lifting point is used to hold the crankshaft. The rope of the inner lifting point is removed, and the crane continues to move the crankshaft. By moving the lifting point on the lifting beam, the crankshaft is pulled out of the rolling mill arch and lifted away; the rolling mill arch is cleaned and repaired, and the crankshaft is lifted and installed in reverse according to the above steps to complete the replacement of the crankshaft. This method overcomes the defects of the traditional crankshaft lifting operation, solves the problem of on-site replacement and lifting of the crankshaft, simplifies the operation process, reduces costs and cycles, and ensures the normal operation of the hot rolling production line. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments: Figure 1 Schematic diagram of the sling structure in this method. DETAILED DESCRIPTION

[0008] Implementation example Figure 1 As shown, the on-site lifting and replacement method of the crankshaft of the fixed-width side press of the hot rolling production line of the present invention comprises the following steps: Step 1: Remove the inner and outer blocks of the crankshaft and move them horizontally to the anti-warping roller frame side of the hot rolling production line; Step 2: Remove the connecting arm and crankshaft takeover bolts that fix the crankshaft; Step 3: Remove the pipeline support and walkway platform on the entrance operation side; Step 4: Use a hand hoist to hold the crankshaft. When the half-haft seat of the crankshaft bearing seat is suspended by a crane, remove the fixing bolts of the half-haft seat by electric heating and lift the half-haft seat away from the bearing seat. Step 5, making a sling, including a sling beam 1, upper sling ears 2 arranged on the top surfaces of both ends of the sling beam 1, and four lower sling ears 3 arranged at intervals on the bottom surface of the sling beam 1, wherein the two middle lower sling ears constitute the inner sling points 31, and the two outer lower sling ears constitute the outer sling points 32, and the upper sling ears 2 and the lower sling ears 3 are respectively provided with shackles 4; The spacing of the four lower lifting ears 3 is determined by the position of the lifting point on the crankshaft and the hoist hand-over distance across the rolling mill arch beam on site; Step 6, the main hook 5 of the crane is connected to the shackle of the upper lifting eye 2 through a sling, and the 30T hoist is hooked on the shackles of the four lower lifting eyes 3 respectively. The crane is driven to the top of the crankshaft, and the 30T hoist of the inner lifting point is used to secure the crankshaft, and the hand hoist is removed, and the crane is directed to move the crankshaft. When the rope of the inner lifting point approaches the rolling mill arch beam, the 30T hoist rope of the outer lifting point is moved to the outer side of the rolling mill arch beam, and the 30T hoist of the outer lifting point is used to secure the crankshaft, and the rope of the inner lifting point is removed. The crane continues to move the crankshaft, and the crankshaft is pulled out and lifted from the rolling mill arch by moving the lifting point on the lifting beam; Step 7: Clean and grind the rolling mill arch, lift and install it in reverse according to the above steps to complete the crankshaft replacement.

[0009] Preferably, the shackles provided on the upper lifting eye and the lower lifting eye are bow-shaped shackles.

[0010] The bow-shaped shackle has a large load-bearing capacity and can withstand a large weight. It is suitable for hoisting operations of crankshafts weighing about 46 tons. When used properly, the bow-shaped design can effectively reduce the risk of accidental detachment of the shackle during the force-bearing process, ensure the safety of the hoisting operation, and improve the safety factor. It is also easy to install, and its shape is convenient for connection with various ropes, chains, etc. It is simple for workers to operate and can be quickly installed in an emergency.

[0011] This method does not require the construction of a special hoisting maintenance platform. When the crankshaft is hoisted and replaced on site, the crankshaft must be hoisted across the beam of the rolling mill arch. Due to the limited construction site, it is impossible to support the crankshaft to be continuously hoisted and pulled out of the rolling mill arch. This method makes a special hoist and solves the problem of the crankshaft crossing the beam of the rolling mill arch during the hoisting process by moving the hoisting point on the hoisting beam. This method can smoothly realize the hoisting and replacement of the crankshaft, meet the maintenance cycle of the fixed-width side press, simplify the operation process, reduce costs and cycles, and ensure the normal operation of the hot rolling production line.

Claims

1. A method for on-site lifting and replacement of a crankshaft of a fixed-width side press in a hot rolling production line, characterized in that The steps include: Step 1: Remove the inner and outer blocks of the crankshaft and move them horizontally to the anti-warping roller frame side of the hot rolling production line; Step 2: Remove the connecting arm and crankshaft takeover bolts that fix the crankshaft; Step 3: Remove the pipeline support and walkway platform on the entrance operation side; Step 4: Use a hand hoist to hold the crankshaft. When the half-haft seat of the crankshaft bearing seat is suspended by a crane, remove the fixing bolts of the half-haft seat by electric heating and lift the half-haft seat away from the bearing seat. Step 5: Make a sling, including a sling beam, upper sling ears arranged on the top surfaces of both ends of the sling beam, and four lower sling ears arranged at intervals on the bottom surface of the sling beam, wherein the two middle lower sling ears constitute the inner sling points, and the two outer lower sling ears constitute the outer sling points, and the upper sling ears and the lower sling ears are respectively provided with shackles; Step 6. The main hook of the crane is connected to the shackle of the upper lifting eye through a sling, and 30T hoists are hooked on the shackles of the four lower lifting eyes respectively. The crane is driven to the top of the crankshaft, and the 30T hoist of the inner lifting point is used to secure the crankshaft. The hand hoist is removed and the crane is directed to move the crankshaft. When the rope of the inner lifting point approaches the beam of the rolling mill arch, the 30T hoist rope of the outer lifting point is moved to the outer side of the rolling mill arch beam, and the 30T hoist of the outer lifting point is used to secure the crankshaft. The rope of the inner lifting point is removed, and the crane continues to move the crankshaft. By moving the lifting point on the lifting beam, the crankshaft is pulled out and lifted from the rolling mill arch. Step 7: Clean and grind the rolling mill arch, lift and install it in reverse according to the above steps to complete the crankshaft replacement.

2. The method for on-site lifting and replacement of the crankshaft of the fixed-width side press of the hot rolling production line according to claim 1 is characterized in that: The shackles arranged on the upper lifting eye and the lower lifting eye are bow-shaped shackles.

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