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Demolition construction scheme of ring cooler

One. Project overview

The ring cooling demolition project of sintering machine in the first ironmaking plant of Maanshan Iron and Steel Co., Ltd. was undertaken by Construction Engineering Company II. This demolition project focuses on the demolition of fans, sealing covers, trolleys and tracks, friction plates and steel structure frames. Choose protective demolition. Before dismantling, all equipment must be numbered for installation. This project is characterized by short construction period, large quantity of work and crossover operation on the construction site. Therefore, our company attaches great importance to this demolition project.

Two. Compilation basis

According to the drawings and demolition requirements provided by Party A's unit, this construction scheme is compiled, and auxiliary tools such as cranes are selected according to the actual weight of objects and the performance table of main lifting tools.

Three. process flow

This demolition belongs to protective demolition, and it must be marked before demolition. It was disassembled from top to bottom. Considering the structure and characteristics of the circular cooler, the fan is removed first, and then the sealing cover is removed. After disassembly above the trolley body, the trolley, track and friction plate are disassembled. Secondly, the disassembly of the transmission part, because the trolley needs to be rotated to cooperate in the project of trolley disassembly, so the disassembly of the transmission part is put behind. Then dismantle the bulk material system and blanking system, and finally dismantle the steel structure frame. In the demolition project, there can be cross demolition and point-by-point demolition, which is embodied in the following construction network plan.

Four: Machine preparation

Chain block 1 ton, 2 ton, 5 ton winch, 50 ton crane, 7 units, 25 ton crane, 10 unit, 12 ton crane and 20 units.

Five: personnel organization

The nature of demolition determines that there can be no damage in the process of demolition, and the construction process must be meticulous. Then, the construction personnel will be arranged according to the site construction environment and time limit. Because it is a demolition project, the requirements for welders and riggers are very high. There are 12 welders, 10 riggers, 4 fitters and 4 riveters.

Concrete construction methods of intransitive verbs

This demolition project adopts top-down protective demolition, because all kinds of equipment should be properly kept according to Party A's requirements during the demolition process ... After demolition, it should be repaired and overhauled in time, put in a unified place at the designated location, and then transported to Hegang site. The specific construction methods can be set as follows. In order to facilitate installation and disassembly according to the construction requirements, please mark it before installation and then disassemble it one by one.

6. 1 fan

The number of fan devices is three, and a general direction can be drawn from the entrance to the exit, namely.

Figure 1: schematic diagram of fan marking and hoisting.

As shown in figure 1, select fan 1, fan 2 and fan 3. The three fans can be disassembled at the same time, starting from the sealed hood and passing through the impeller, reducer and motor in the middle. Choose 50-ton crane. Schematic diagram of the foothold and hoisting of the crane is as shown in figure 1, and chain block cooperates in dismantling. Before disassembly, the electronic control system and oil circuit must be disassembled.

6.2 sealing cover

Like the fan, the sealing covers are marked from the inlet to the outlet, including the inlet end sealing cover and the outlet end sealing cover, with 5 sealing covers in the middle, 1 1 sealing covers, 2 expansion sealing covers and 2 expansion sealing covers. The other three fans have a sealing cover on the left and right sides, and there are two sealing covers in the middle of the fans. * * * There are 44 sealing covers, which can be numbered from 1 to 44 with paint (the sealing covers around the fan can also be excluded, and other sealing covers can be numbered in various forms). As can be seen from the site drawings, the heaviest seal coat is 1320kg. Therefore, according to the performance table of main hoisting machinery, a 25t crane can be selected, and a 50t crane can be selected in coordination with the complex hoisting points on the construction site. In order to facilitate transportation, the removed sealing cover is divided into three pieces, which are transported in time, and the internal small system is marked to avoid the complexity of the site. In the process of disassembly, it must be noted that in the process of cutting screws, cranes or chain block must be used for protection to prevent accidents.

6.3 trolley

This number is the same as the above method, and * * * is a 45-gauge trolley. During the demolition process, Party A shall cooperate with the rotation. The weight of the trolley is 1437kg, and a 25t crane can be selected for hoisting. The schematic diagram of lifting is shown in Figure 2. In the process of putting down the car, it is transported to the designated place in time for maintenance with the help of forklift. In addition, it should be noted here that in the process of disassembling the trolley, one side of the trolley is removed and the other side is not disassembled, which may lead to the imbalance of the whole side, so that the friction wheel and the friction plate are engaged too deeply. Therefore, Party A is required to cooperate with the rotation, take a car every few cars, so as to make the car rotate smoothly in the process of disassembly, and use a forklift to cooperate with the repair of the car in the process of putting the car back to the designated position in time.

Fig. 2: Transmission device identification and trolley hoisting schematic diagram.

6.4 Tracks and friction plates

Because this ring cooler is disassembled and installed, because the crawler belt and friction plate have been worn in operation before, it must be assembled and installed in the original way, and the order cannot be reversed. Otherwise, it may cause unnecessary situations such as trolley running, non-rotation of rollers, excessive engagement of blocking wheels, etc., so the numbers are numbered from the entrance to the exit according to the above method. Track * * * has three one-cycle coolers, which can be disassembled at the same time. Choose 12 ton crane, chain block and other tools for demolition, and carry out the narrow space through hoisting. The quantity of this part is very small, so it will be determined according to the actual situation during on-site construction.

Friction plate is one of the important equipment of ring cooler. When disassembling, it must be handled carefully, and it must not be deformed, and it should also be protected during secondary transportation. Friction plates are connected by reaming bolts, and the bolts can be removed first (pay attention to preparing reaming bolts when installing). Ring cooler cycle *** 15.

Figure 3: Schematic diagram of distribution and hoisting of friction plates. The weight of a single friction plate is 560kg, and a crane of 12 ton can be selected for hoisting. The position and station of the crane are reasonable, as shown in Figure 3.

6.5 transmission parts

The transmission device of the ring cooler consists of two transmission systems, which are symmetrically distributed on both sides of the whole ring cooler system. Each transmission device has an upper friction wheel and a lower friction wheel to drive the friction plate connected to the trolley to meet the speed requirements. As mentioned above, a fixed direction from the entrance to the exit can be set, so that the transmission devices 1 and 2 are labeled, as shown in fig. 2. Pay attention to protect the reducer and friction wheel during removal. You can choose a 25-ton crane to dismantle it, and then open the reducer for maintenance.

6.6 Platform and steel structure frame

After the above-mentioned equipment is dismantled, what remains is the dismantling of some basic planes and platforms such as brackets, including trolley brackets, fan brackets, transmission part brackets, and some ladders and protective railings. The marks of the fan bracket and the transmission part bracket can be determined according to the marks of the fan and the transmission device, namely, the fan bracket 1, 2 and 3, the transmission part bracket 1, 2, and the trolley bracket can also be determined according to the marks of the fan and the transmission device. The removal of this part should start with the removal of the fan bracket and the gearbox part bracket. In order to facilitate transportation, the form of surface removal should be adopted, that is, for the four-legged steel structure, two auxiliary frames connected together can be selected without removal. After the fan bracket and the transmission part bracket are removed, the trolley bracket will also be removed, which can be removed at multiple points and started at the same time. In the process of demolition, the internal small system should be marked well, and 12 ton crane should be selected.

The above is the marking and disassembly of all devices. In addition, individual devices, such as hoppers and bulk material systems, do not need to be marked. Only the general direction is determined here. For example, the small internal structure (such as the transmission part and the fan part) is disassembled in blocks, so it is necessary to mark the small internal system carefully to prevent confusion and bring unnecessary trouble to the installation. Expounds the demolition process of each equipment structure from a big aspect, and determines the division of small details according to the site construction situation.

Seven: Key points of quality management and safety control measures

1. Establish and improve the safety system, give safety education to the construction personnel before entering the site, strengthen safety awareness and quality awareness, earnestly do all the preparatory work, fully understand the drawings and materials of the demolition project, investigate the construction site, and make safety technical disclosure to the demolition construction personnel. Prepare construction organization design or safety special construction scheme, and formulate emergency rescue plan for safety accidents. Ensure the project quality is completed on schedule.

2. Hard enclosure and eye-catching warning signs should be set up in the construction area of demolition project. Non-construction personnel are not allowed to enter the construction area. Demolished items should be sorted out and repaired in time, put in designated places and kept in centralized custody.

4. Welding equipment shall be clearly marked and provided with fire and explosion-proof measures.

5. Lifting equipment and tools should be managed by special personnel, and can only be used after being confirmed safe. The length and diameter of steel wire rope used for dismantling and hoisting of large pieces should be reasonably selected, the hoisting point should be confirmed before use, and the signal should be clear during hoisting.

6. Construction personnel should be clear about the safety matters in the operation, strictly abide by the safety technical regulations and operating procedures, and when the demolition project may cause danger to the safety of adjacent buildings, corresponding protective measures must be taken to evacuate and resettle the personnel in the building.

7. The personnel entering the site should prepare complete safety protection articles for the demolition workers, and it is forbidden to work after drinking. Pay attention to prevent temperature and reduce summer heat in hot weather.

8. When the construction stops, cut off the power supply and check the site to ensure that there are no safety factors before leaving.

9. Unsafe factors found in the construction should be eliminated in time, otherwise the operators have the right to refuse the operation. When there are overhead lines or cable lines on the construction site, contact Party A and take protective measures to ensure safety before construction.

10. Before the demolition operation, the construction unit shall inspect all kinds of pipelines in the building and confirm that they are all cut off before construction (transmission devices are reserved). If unknown objects are found in the demolition work, the construction should be stopped, corresponding emergency measures should be taken to protect the site and report to the relevant departments in time.

1 1. Strengthen lighting during construction at night, set up protective platforms when crossing up and down, assign special personnel to supervise and coordinate, and don't throw things down at will.

12. According to the working environment of the demolition project construction site, corresponding fire safety measures should be formulated. Fire truck access should be set up at the construction site to ensure adequate fire water supply. When the oil pollution on site is serious, adequate fire extinguishing equipment should be provided to prevent fire and prevent skid.

Eight: Environmental Protection Measures and Civilized Construction

1. Set up eye-catching signs, signs and notices within the scope of the construction section.

2. Machines and materials should be neatly stacked, and the remaining materials should be cleared in time.

3. During the demolition operation, it is forbidden to gather or pile materials on the platform, and the operators should stand on the stable structure or scaffold, and the dismantled components should be placed in a safe place.

4. Waste oil and waste on site shall not be discharged at will, and shall be treated centrally.

5. After demolition, clean up the site to complete the work, use all materials and clean up the site.

FYI