Knowledge | 2022-10-26
Safety protection measures for organic solvent ultrasonic cleaning
Analysis of fire safety hazards of organic solvents, organic solvents have flammable and explosive, so it is necessary to establish fire prevention, and explosion of the corresponding countermeasures. General organic solvent combustion needs to meet three conditions: first, the existence of flammable vapor, second, there is an ignition source, and third, the existence of necessary oxygen. Most of the organic solvents used in the aerospace field are highly volatile, so there will be a certain amount of flammable vapor during the cleaning operation.
The safety and protection measures of ultrasonic cleaning of organic solvent can eliminate the hidden trouble of organic solvent poisoning and fire protection to the maximum extent only by paying great attention to the prevention of organic solvent poisoning and fire protection, we should give priority to prevention and take preventive measures from four aspects.
Safety protection control of raw materials, equipment, facilities, and site
The law of the People's Republic of China on the prevention and control of occupational diseases requires that early prevention work should be done well, it also emphasized that construction units of new construction, expansion, and reconstruction projects, as well as projects of technological transformation and improvement of technology, may produce occupational hazards, at the stage of feasibility demonstration, the pre-evaluation report on occupational hazards shall be submitted to the administrative department of Health. National Laws stipulate that raw materials, products, and even intermediate substances in the production process must be replaced by non-toxic substances as far as possible, low-toxic substances must be substituted for high-toxic substances, and exposure to toxic substances must be controlled at the source of production. Therefore, for the analysis of fire safety, toxicity, and ultrasonic cleaning hazards of organic solvents, the following measures should be taken for raw materials, equipment, facilities, sites, and so on:
(1) improve the production process. It is an effective method to improve the production process by substituting the substances with high combustion and explosion risk and low toxicity for those with high combustion and explosion risk and high toxicity.
(2) to prevent the organic solvent vapor from forming a flammable system with the air, the cleaning operation should be carried out in a certain enclosed space, and the forced exhaust device should be arranged in the enclosed area, this can effectively reduce the content of combustibles in the air, reduce the risk of fire and explosion accidents, and reduce the harm of organic solvent vapor to the human body.
(3) control of ignition source. To prevent fire and explosion accidents, it is an important measure to control or eliminate the fire source. Therefore, the door of the cleaning room to set static eliminator, personnel, and items in the cleaning room before the elimination of static electricity can enter after, to isolate the ignition source, isolate spark, open fire, and other ignition sources. Consider installing or isolating electrical equipment from hazardous locations as appropriate, and minimize the use of portable electrical equipment. Electrical equipment should be reliably grounded with a resistance of less than 4 & Omega; To eliminate electrical sparks.
(4) fire-proof and explosion-proof safety devices shall be installed in the cleaning workshop. Fire and explosion-proof safety device is the general name for all kinds of instruments, instruments, and devices, such as detection, control, interlock, protection, alarm, and so on, which are set up in the production system to prevent accidents. Therefore, the cleaning room should be installed flammable gas alarm controller, at any time to monitor the concentration of flammable gas in the room, control the concentration of gas, and a cleaning device equipped with a mandatory exhaust function outside, when the vapor concentration reaches a certain concentration, the alarm is issued to avoid the occurrence of disasters. At the same time, the cleaning room installs a forced exhaust device to reduce the concentration of flammable gas at any time.
(5) the selection and installation of electrical equipment shall adopt an explosion-proof switch, explosion-proof socket, and explosion-proof lamp tube, and should consider preventing external effects (such as chemical action, mechanical action, heat, electrical, moisture) on the explosion-proof performance have adverse effects. Explosive gas environment electrical wiring installation in line with AQ3009-2007, “Dangerous places electrical explosion-proof safety code” provisions.
(6) the temperature of the cleaning fluid should be displayed on the cleaning equipment in real-time to avoid the fire hazard caused by excessive temperature; the cleaning room should be equipped with a fire extinguisher for storing the safe organic solvent; the cleaning room should be equipped with a steel heat-insulated fire door; Overload protection device for electrical equipment.
(7) install a 24-hour monitoring device to monitor the situation in the clean room at any time to avoid the occurrence of dangerous situations. To deal with the harm of noise caused by ultrasonic cleaning, sound absorption accessories can be installed on the end and around the cleaning device. For some the device is not good sealing, cleaning device can be added to the outside of a noise enclosure, reducing the escape of noise.