When the aerial vehicle runs to a certain period (traveling to a certain distance), the parts will naturally loosen and wear out. Therefore, it is necessary to carry out compulsory preventive maintenance. Regular maintenance is divided into one, two and three levels of maintenance. First, a maintenance The first-level maintenance is the technical maintenance that is centered on lubricity and sturdiness in the 1,500-2,400-km interval mileage of high-altitude operation vehicles. Its main content is: 1. Check and sturdy bolts and nuts on exposed parts of aerial vehicles. 2. Add lubricating oil (fat) according to the specified lubrication points. 3, check the oil level within the assembly, when the lack of lubrication according to the standard. 4, cleaning gasoline, oil, air filter. After the first-level maintenance of aerial vehicles, it should achieve the purpose of cleanliness, complete equipment, firm connection, smooth flow of the three filters (gasoline, oil, air), good lubrication, and no leakage. Second, two maintenance The secondary maintenance is the technical maintenance based on inspection and adjustment after the high-altitude vehicle has traveled between 6,000-8,000 kilometers. At this time, in addition to carrying out a level 1 maintenance project, the following items should be added: 1. Check and adjust the technical status of the aerial vehicle engine and electrical equipment. 2. Clean crankcase (oil sump) and oil filter, replace new oil, add grease. 3, clean gasoline filter. 4. Check the technical status of steering, brake mechanism and clutch. 5. Check the other assemblies and adjust them as needed. 6. Check the tyres of aerial vehicles and perform transposition. Three, three maintenance The three-level maintenance is the technical maintenance centered on the dismantling, cleaning, inspection and adjustment of the assembly after the lift truck has traveled 36,000 to 40000 kilometers. At this time, in addition to repeating the first and second maintenance items, the following items should be added: 1. Check the engine of the aerial working platform to remove carbon deposits, gel deposits and cooling scales. 2. Disassemble the chassis assembly as required, clean, inspect and adjust to eliminate hidden dangers. 3. Inspect the frame and body of the aerial work vehicle and perform rust removal, welding and replenishing as required.
Pharmaceutical intermediates are actually some chemical raw materials or products used in the synthesis process. Chemical products do not need that kind of production license. They can be produced in ordinary chemical plants. As long as they reach some grades, they can be synthesized appropriately.
Types of intermediates
Intermediates refer to semi-finished products, which are intermediate products in the production of certain products. For example, to produce a product, it can be produced from intermediates to save costs.
Intermediates are formed from cyclic compounds such as benzene, naphthalene, anthracene, etc. through sulfonation, alkali fusion, nitration, reduction, etc. For example, benzene is nitrated to nitrobenzene, and then reduced to aniline, which can be chemically processed into dyes, drugs, vulcanization accelerators, etc. Both nitrobenzene and aniline are intermediates.
There are also acyclic compounds such as methane, acetylene, propylene, butane, butene, etc. through dehydrogenation, polymerization, halogenation, hydrolysis and other reactions. For example, butane or butene is dehydrogenated to butadiene, which can be chemically processed into synthetic rubber, synthetic fibers, and the like.
Butadiene is an intermediate.
It originally refers to the intermediate products produced in the process of synthesizing chemical products such as spices, dyes, resins, drugs, plasticizers, rubber accelerators, etc. using coal tar or petroleum products as raw materials. It now generally refers to various intermediate products obtained in the process of organic synthesis.
5-Bromo-2 4-dichloropyrimidine,4-Bromo-2-fluorobenzoic acid,4-Bromo-2-fluorobenzaldehyde,6-(4-Aminophenyl)-4 5-dihydro-5-methyl-3(2H)-pyridazinone Shenyang TYSChem Co., Ltd. , https://www.custchemvip.com
Three-level maintenance of aerial vehicles
Three-level maintenance of aerial vehicles