Method for lifting and dismounting manhole door through worm and gear elevator

Abstract

The invention discloses a method for lifting and dismounting a manhole door by using a worm and gear lifter. The height of a manhole door cover plate of a generator is different due to the fact that operators are different in height and uneven in force application, and potential safety and technical hazards exist. The device comprises a base frame, two base lifters are fixed on the base frame, base lifter flange plates of the two base lifters are fixed on a bottom plate, a main lifter is fixed on the bottom plate, a manhole door seat is arranged on a main lifter flange plate of the main lifter, and a manhole door seat is arranged on the main lifter flange plate of the main lifter. The fixing lead screw penetrates through the installation hole in the manhole door and then is in threaded connection with the threaded hole in the plane of the bottom of the generator. The device is used for assisting the disassembly and assembly of the generator manhole door.

Description

TECHNICAL FIELD

[0001] The present application relates to a method for lifting and dismounting manhole door by using worm gear hoist. BACKGROUND

[0002] During the generator maintenance process in power plant, the generator manhole door is located in the abdomen of the generator, the cover plate of the generator manhole door is 610*540mm in length and width, and weighs about 100kg, at least four people are needed to dismount and mount the generator manhole door each time, a scaffold needs to be erected, and the generator manhole door cover plate is lifted to the shoulder height position by manpower, and the bolts are brought in. During this period, due to the different heights of the workers and the uneven force, the height of the generator manhole door cover plate is not the same, which exists safety and technical hidden dangers. SUMMARY

[0003] The purpose of the present application is to provide a method for lifting and dismounting manhole door by using worm gear hoist, so as to solve the above technical problems.

[0004] The above purpose is realized by the following technical scheme: A method for lifting and dismounting manhole door by using worm gear hoist, the method comprises the following steps: (1) When dismounting the manhole door, first remove the bolts installed at the four corners of the manhole door, then thread the fixed screw rod through the installation hole after the dismounting bolt of the four corners of the manhole door and the threaded hole of the bottom plane of the generator; (2) Place the device under the manhole door, the top of the base frame has a through hole for the main lifting screw rod of the main hoist to pass through, adjust the height so that the main hoist flange plate of the main hoist contacts the bottom of the manhole door, then remove the remaining bolts installed on the manhole door, adjust the height of the main hoist to lower, then adjust the base hoist to continue to lower the height of the manhole door until the fixed screw rod is separated from the manhole door, and the manhole door can be lifted down; (3) When installing the manhole door, first thread the four fixed screw rods into the threaded holes at the four corners of the bottom plane of the generator, then place the device under the bottom plane of the generator, lift the manhole door to this position and place it on the main hoist flange plate, then adjust the base hoist to raise the height of the manhole door, and stop when it is about to contact the bottom of the fixed screw rod; (4) Then adjust the position of the manhole door so that the four fixed screw rods can pass through the corresponding installation holes at the four corners of the manhole door, after adjustment, continue to operate the main hoist to raise the height of the manhole door until it contacts the bottom plane of the generator, then install bolts in all the installation holes of the manhole door except the installation hole connected with the fixed screw rod on the bottom plane of the generator, after installation, adjust the main hoist to lower the height of the device, then unscrew the fixed screw rod and install the bolts at the four corners to complete the installation of the manhole door.

[0005] The method for lifting and disassembling a manhole door by using a worm gear and worm lifting machine comprises a base frame, two base lifting machines fixed on the base frame, a base lifting machine flange plate of the two base lifting machines fixed on a base plate, a main lifting machine fixed on the base plate, a manhole door seat on a main lifting machine flange plate of the main lifting machine, and a fixed screw rod screwed with a threaded hole in a bottom plane of a generator after passing through an installation hole in the manhole door.

[0006] The method for lifting and disassembling a manhole door by using a worm gear and worm lifting machine, wherein the main lifting machine and the base lifting machine are both worm gear and worm screw rod lifting machines.

[0007] The method for lifting and disassembling a manhole door by using a worm gear and worm lifting machine, wherein the base frame is a square ring frame, and the top of the square ring frame has a through hole for the main lifting screw rod of the main lifting machine to pass through. Beneficial effects

[0008] 1. The present application can support the manhole door to lift it, facilitate the installation and disassembly of the manhole door, ensure that the manhole door cover plate is uniformly stressed during disassembly, and protect the generator manhole door sealing gasket from damage during assembly.

[0009] 2. In the process of disassembling the manhole door, the bolts installed at the four corners of the manhole door are first removed, then the fixed screw rod is screwed with a threaded hole in the bottom plane of the generator after passing through the installation hole of the bolts removed from the four corners of the manhole door, then the device is placed under the manhole door, the height is adjusted so that the main lifting machine flange plate of the main lifting machine contacts the bottom of the manhole door, then the remaining bolts installed on the manhole door are removed, the height of the main lifting machine is adjusted to lower it, then the base lifting machine is adjusted to continue lowering the height of the manhole door until the fixed screw rod is separated from the manhole door, and the manhole door can be lifted down. BRIEF DESCRIPTION OF DRAWINGS

[0010] Fig. 1 It is a front view of the present application; Fig. 2 It is a front view of the fixed screw rod not installed with the bottom plane of the generator; Fig. 3 It is a top view of the fixed screw rod not installed with the bottom plane of the generator; Wherein: 1, the bottom plane of the generator; 2, the fixed screw rod; 3, the main lifting machine flange plate; 4, the manhole door; 5, the main lifting machine; 6, the main lifting machine hand wheel; 7, the base plate; 8, the main lifting machine screw rod; 9, the base lifting machine; 10, the through hole; 11, the base lifting machine hand wheel; 12, the connecting rod; 13, the base frame; 14, the base lifting machine flange plate; 15, the nut. DETAILED DESCRIPTION

[0011] Reference Figs. 1-3 A method for lifting and disassembling a manhole door using a worm gear jack, the method comprising the following steps: (1) When disassembling the manhole door, first remove the bolts installed at the four corners of the manhole door, and then thread the fixing screw through the installation holes after removing the bolts at the four corners of the manhole door and thread it into the threaded hole on the bottom plane of the generator. (2) Place the device below the manhole door. The top of the base frame has a through hole for the main lifting screw of the main elevator to pass through. Adjust the height so that the main lifting flange of the main elevator contacts the bottom of the manhole door. Then remove the remaining bolts on the manhole door. Adjust the height of the main elevator to lower it. Then adjust the base elevator to lower the height of the manhole door until the fixing screw is separated from the manhole door. Then the manhole door can be lifted down. (3) When installing the manhole door, first connect the four fixing screws to the threaded holes at the four corners of the bottom plane of the generator, then place the device below the bottom plane of the generator, lift the manhole door to this point and place it on the flange plate of the main elevator, then adjust the base elevator to raise the height of the manhole door, and stop when it is about to touch the bottom of the fixing screw. (4) Then manually adjust the position of the manhole door so that its four fixing screws can pass through the corresponding mounting holes at the four corners of the manhole door. After the adjustment is completed, continue to operate the main elevator to raise the height of the manhole door until it touches the bottom plane of the generator. Then install bolts in all mounting holes of the manhole door and the bottom plane of the generator except for the mounting holes for connecting the fixing screws. After the installation is completed, adjust the main elevator to lower the height of the device. Then unscrew the fixing screws and install the bolts at the four corners to complete the installation of the manhole door.

[0012] A method for lifting and disassembling a manhole door using a worm gear jack includes a base frame 13, on which two base jacks 9 are fixed. The base jack flange plates 14 of the two base jacks are fixed to a base plate 7. A main jack 5 is fixed to the base plate. Three through holes 10 are provided on the upper surface of the base frame. One through hole is in the center for the main jack screw of the main jack to pass through, and the other two through holes are for the base jack screws of the base jacks to pass through. A center hole 16 is provided in the center of the base plate for the main jack screw to pass through. The handwheels of the two base jacks are connected by a connecting rod 12, so that rotating one handwheel allows for synchronous rotation of both handwheels, achieving synchronous operation of the two base jacks and ensuring stable height adjustment of the base plate. A manhole door 4 is seated on the main jack flange plate 3 of the main jack. A fixing screw 2 passes through the mounting hole on the manhole door and is threadedly connected to a threaded hole on the bottom plane 1 of the generator.

[0013] The main elevator and the base elevator are both worm and screw rod elevators.

[0014] The base frame is a square ring frame, and the top of the square ring frame has a through hole 10 for the main lifting screw rod of the main elevator to pass through.

[0015] Working principle: first, when the manhole door is disassembled, the bolts installed at the four corners of the manhole door are removed, then the fixed screw rod is screwed into the threaded hole in the bottom plane of the generator after passing through the mounting hole of the four corner bolts of the manhole door, then the device is placed below the manhole door, the height is adjusted so that the main lifting flange plate of the main elevator contacts the bottom of the manhole door, then the remaining bolts on the manhole door are removed, the height of the main elevator is adjusted to lower it, then the base elevator is adjusted to continue to lower the height of the manhole door until the fixed screw rod is disengaged, and the manhole door can be lifted down. When installing the manhole door, first screw the four fixed screw rods into the threaded holes in the four corners of the bottom plane of the generator, then place the device below the bottom plane of the generator, lift the manhole door to this position and place it on the main lifting flange plate, then adjust the base elevator to raise the height of the manhole door, stop when it is about to contact the bottom of the fixed screw rod, then adjust the position of the manhole door manually so that the four fixed screw rods can pass through the corresponding mounting holes in the four corners of the manhole door, after adjustment, continue to operate the main elevator to raise the height of the manhole door until it contacts the bottom plane of the generator, then install bolts in all the mounting holes of the manhole door except the mounting hole connected to the fixed screw rod on the bottom plane of the generator, after installation, adjust the main elevator to lower the height of the device, then unscrew the fixed screw rod and install the bolts at the four corners to complete the installation of the manhole door. The height of the manhole door is raised by the elevator, which can prevent the phenomenon of uneven height of the generator manhole door cover caused by different heights of workers and uneven force.

Claims

1. A method for lifting and disassembling manhole doors using a worm gear jack, characterized in that: The method includes the following steps: (1) When disassembling the manhole door, first remove the bolts installed at the four corners of the manhole door, and then thread the fixing screw through the installation holes after removing the bolts at the four corners of the manhole door and thread it into the threaded hole on the bottom plane of the generator. (2) Place the device below the manhole door. The top of the base frame has a through hole for the main lifting screw of the main elevator to pass through. Adjust the height so that the main lifting flange of the main elevator contacts the bottom of the manhole door. Then remove the remaining bolts on the manhole door. Adjust the height of the main elevator to lower it. Then adjust the base elevator to lower the height of the manhole door until the fixing screw is separated from the manhole door. Then the manhole door can be lifted down. (3) When installing the manhole door, first connect the four fixing screws to the threaded holes at the four corners of the bottom plane of the generator, then place the device below the bottom plane of the generator, lift the manhole door to this point and place it on the flange plate of the main elevator, then adjust the base elevator to raise the height of the manhole door, and stop when it is about to touch the bottom of the fixing screw. (4) Then manually adjust the position of the manhole door so that its four fixing screws can pass through the corresponding mounting holes at the four corners of the manhole door. After the adjustment is completed, continue to operate the main elevator to raise the height of the manhole door until it touches the bottom plane of the generator. Then install bolts in all mounting holes of the manhole door and the bottom plane of the generator except for the mounting holes for connecting the fixing screws. After the installation is completed, adjust the main elevator to lower the height of the device. Then unscrew the fixing screws and install the bolts at the four corners to complete the installation of the manhole door.

2. The method for lifting and disassembling a manhole door using a worm gear jack according to claim 1, characterized in that: Its components include a base frame, on which two base lifts are fixed. The base lift flanges of the two base lifts are fixed to a base plate. A main lift is fixed to the base plate. A manhole door is seated on the main lift flange of the main lift. A fixing screw passes through the mounting hole on the manhole door and is threadedly connected to the threaded hole on the bottom plane of the generator.

3. The method for lifting and disassembling a manhole door using a worm gear jack according to claim 2, characterized in that: Both the main lift and the base lift are worm gear screw jacks.

4. The method for lifting and disassembling a manhole door using a worm gear jack according to claim 3, characterized in that: The base frame is a square ring frame, and the top of the square ring frame has a through hole for the main lifting screw of the main elevator to pass through.

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