What should I do if there is heavy oil mist during cutting oil processing?
August 16, 2021
During metal processing such as turning, milling, drilling, and grinding, a large number of oil mist particles will be formed in the air due to the use of Metal Working Fluid. Metalworking fluid is a very complex mixture. In addition to hydrocarbons, it may also contain various chemical substances such as sulfonates, fatty amines, nitrates, dyes, and fungicides. If it is a processing fluid that has been put into use, due to the oxidation of hydrocarbons, the reproduction of microorganisms or the pollution of external impurities, the metal processing fluid may contain more chemical substances that are harmful to the human body and the ecological environment. Therefore, controlling the oil mist concentration in the metal processing workshop is an important measure related to the occupational safety and health of the production enterprise.
1. The existence of oil mist The metal cutting process can produce the following 3 types of oil mist: 1. Clean oil mist produced by jet impact, free of solid dust. 2. The smoke produced by evaporation or burning caused by the high temperature of heating or high-speed cutting. 3. The oil mist containing grinding dust generated by the metal working fluid jet during grinding. The way the oil mist is generated is different, and its particle diameter range is also quite different. In general, the oil mist produced by the mechanical atomization process mainly exists in the form of droplets, with a wide range of droplet diameters, usually 2-10um. The oil vapor generated by evaporation will also form a very small diameter condensed suspension during the condensation process, the particle size is usually below 2um. Medical research has proved that oil vapor and large particle droplets are relatively less harmful to human lungs. The oil mist in the form of oil vapor is inhaled into the lungs and then exhaled. They will not be captured by the alveoli, and the oil droplets of large particles cannot enter the lungs through the nose and bronchi. Only the oil mist particles that exist in the form of droplets and have a diameter of less than 5um can reach the alveoli smoothly and settle in the lungs, thus causing greater harm to the human body. 2. The harm of oil mist The existence of metal working fluid oil mist greatly increases the fire hazard, and at the same time, the possibility of slipping on the floor with oil mist increases. The air with oil mist is discharged from the workshop, which will also pollute the environment. The biggest harm of metalworking fluid oil mist is also affecting the health of workers exposed to it. Long-term exposure to metalworking fluid oil mist can cause diseases, allergic skin diseases and malignant tumors, and may cause genetic effects. Another major hazard of metalworking fluid oil mist is its carcinogenic possibility. The carcinogenicity of metalworking fluids mainly depends on the concentration of its additives, contamination and conditions of use. At present, there is no research on the carcinogenicity of metalworking fluids for humans. Although there is still controversy about the carcinogenicity of metalworking fluids and their oil mist, experimental studies with animals have found that the oil Fog can cause skin tumors/skin cancer papilloma, lung cancer and pancreatic cancer. 3. Current status of oil mist control in machining workshops at home and abroad There are two main methods for controlling the concentration of oil mist particles in the atmosphere of the workshop: mechanical and chemical. 1. Mechanical method Including the installation of exhaust fans, oil mist traps, setting up protective covers or splash guards around the machine tool, etc. At the same time, to meet environmental protection requirements, the exhaust gas should be filtered for oil mist. Oil mist filters are important equipment to complete this task. , The oil mist collection rate of good quality equipment can reach more than 98%. At present, most of the processing workshops use mechanical oil mist purification methods. The exhaust hood is used to supplement the oil mist in the processing center on the spot. The fan is pumped to the centralized or stand-alone oil mist purifier. The Filter Material is filtered and discharged. 2. Chemical method Use a special low oil mist machining lubricant. From the perspective of cutting fluids, the use of class III oil or ester oil and low viscosity oil as the Base Oil of the cutting fluid can reduce the generation of oil mist to a certain extent. Oil-based cutting fluid with high viscosity is not easy to be dispersed, and it is not easy to form oil mist. The use of cutting fluids containing high-molecular compounds such as (polyethylene oxide, polyisobutylene, polymethacrylate) is often used as an anti-fogging agent because of its large cohesive force, which is not easy to be crushed and the larger the molecular particles. The harm caused by the oil mist of the processing fluid in the machining workshop has attracted the full attention of the world. Although the installation of the oil mist purification system increases project investment, it can greatly reduce the hazard of oil mist, improve labor safety and health, and reduce air pollution. The emission of waste has become a development trend. my country should also speed up the corresponding work, formulate control standards for oil mist, guide the design and implementation of the project, and protect the health of workers.
