Difficulty in disassembly and installation caused by inadequate combination of looseness and tightness during bearing installation
In this type of malfunction, due to the inconsistent tightness status between the components in the ship’s engine room, it is important to ensure that the components are not too loose or too tight during installation. The solution to such faults in the engine room equipment of ships is to use the principle of “thermal expansion and contraction”. Similarly, engine room components will contract when the temperature is cold and expand when the temperature is high. In the engineering of ship engine room equipment, sometimes the disassembly and assembly of components is a frequent task. However, when encountering difficulties in disassembly and assembly, the maintenance personnel of the unit often lack certain experience, and the efficiency of repair and maintenance is low. For example, in the combination problem between piston bearings and connecting rods, the difficulty of disassembly and assembly increases due to interference fit. When dismantling bearings, it is relatively easy because the dismantled parts are no longer in use, and slight damage to the parts is not a problem. However, during the installation of bearings, interference fit will increase the difficulty of installation. Although external mechanical equipment such as steel round plates can effectively assist, they will cause certain damage to the bearings. In severe cases, excessive compression deformation of the bearings will affect their performance in subsequent use, threatening the operational efficiency and safety of system components. Sometimes, it may also cause excessive component damage and cannot be put into use. These measures are labor-intensive and not worth it. The matter.
Solution: Based on the principle of “thermal expansion and contraction” of objects, freeze the bearings in an ice storage (at a temperature of about -20 ℃) for a certain period of time before installation. At the same time, prepare an iron container, in which oil with a temperature of about 100-120 ℃ is prepared. Let the connecting rod stand in the oil for a certain period of time. At this time, due to the principle of thermal expansion and contraction, the bearings will contract to a certain extent, and the connecting rod will also expand to a certain extent. When installing both, it is already very easy, which will not cause damage to the two and can accurately position the installation. Of course, in this maintenance and upkeep process, it is important to note that the time and temperature control for both in the engine oil or cold storage should be appropriate. For example, the temperature for standing in the ice storage should reach -20 ℃ for 12 hours, while the temperature for standing in the engine oil for the connecting rod should be above 100 ℃, and the standing time should be controlled within 0.5h-40min. When taking it out, measures should be taken to remove impurities at the top of the connecting rod and clear its surface. In addition, the same road can also be used to clear faults on components such as gears and coppers, ensuring that the components are not damaged.
Pulling issues with components such as the 2-copy forest
Ship equipment manufacturers often use interference fit to combine centrifugal pump copies with pump shafts. When repairing centrifugal pumps, a puller is often used to unload the copy forest. During the disassembly process, due to uneven force distribution, the time and efficiency of disassembling the Kebeilin are not high, and the process of repairing the centrifugal pump wastes a lot of time. Although some high-temperature and high-pressure welding equipment may be borrowed during the actual maintenance process, this will cause damage to the stability of the Kebeilin, and also lead to its deformation, affecting subsequent use and threatening safety. Solution: To solve the problem of difficult disassembly of Kaobeilin, you can create a simple drawing tool yourself and operate it specifically for specific problems. Sometimes it can solve problems well while avoiding safety and damage issues. For example, groove steel can be used to open a certain number of holes on both sides of the groove steel, and extended bolts can be inserted into the holes. At this time, the groove steel is equivalent to a flat and long crossbeam. Install handrails on the groove steel beams. During the dismantling operation of the copying forest, connect the groove steel beams to the copying forest with flanges and bolts for fixation. Install jacks between the groove steel beams and the copying forest to separate the copying forest from the centrifugal pump and achieve the purpose of repairing the centrifugal pump.
Cleaning of smoke and dust from the 3-way exhaust duct or exhaust valve
In airport equipment, there are many exhaust valves, exhaust holes, and pipelines. Regular dust and dust cleaning is necessary in the daily maintenance of cabin equipment. Especially the cleaning work of the exhaust valve of the main engine. Effectively cleaning the dust inside the exhaust valve and exhaust channel of the host can control the amount of combustion materials, improve the cooling effect of fresh water, and prolong the service life of the valve. The traditional dust cleaning work of exhaust valves often involves maintenance personnel using some scrapers or dust removal equipment to clean the flow channel or valve. The methods and methods are relatively outdated and can damage the surface of the flow channel to varying degrees, affecting the stability performance of the equipment. During the dust cleaning process, a lot of time is wasted, and the work efficiency is very low. Solution: Dust cleaning work is indispensable, and the process of dust cleaning needs a regular cycle to ensure that the flow channel and valve are in a normal working range. However, mechanical dust removal methods have a significant dependence on humans and can cause varying degrees of damage to equipment. Changing the approach and using clean water for dust removal can greatly avoid these drawbacks. For example, after disassembling components such as valve heads, the difficulty of cleaning can be greatly reduced by using clean water and cotton felt. Especially, the dust on the surface of the flow channel will flow out of the chamber wall along the clean water, and the accumulated water after cleaning can also flow out along the exhaust flow channel. This method is also very practical in cleaning components such as pistons and rotors of cabin equipment. In the process of cleaning with clean water, in order to improve the efficiency of cleaning, cleaning agents can also be added appropriately to the clean water for better cleaning effect. This method of clearing valves and flow channels with clean water has a fast and efficient overall process. Compared to traditional scraping operations, it does not cause excessive pollution to the surrounding environment and people’s clothing. However, if there are some residual oil stains, the water and oil cannot dissolve with each other, and the effect may not be good. It should be noted that cleaning with clean water and dust will leave water on some surfaces, which may cause rust. At this time, some engine oil can be sprayed on the surface appropriately.