PREFACE: Spin pack components, metering pump and candle filter will all be clogged with dirt after being used for a certain period of time. The pressure of the spinning components and the pressure difference between the inlet and outlet of the melt filter will increase, so they need to be switched and cleaned before they can be used again. Cleaning mainly uses physical and chemical methods to calcine, dissolve, oxidize or hydrolyze the adhered polyester at high temperatures, and then perform water washing, acid-base washing and ultrasonic cleaning.
1. Calcination method
The calcining method is to build a furnace with refractory materials, use electric heating rods to heat, and use platinum resistance or thermocouple thermometers to control and indicate the temperature. When calcining, put the object to be cleaned into the furnace, calcine at 400-450°C for about 6 hours, and then remove the dust.
2. Salt bath method
This method is to burn the spinning components, metering pump, and melt filter element in a decomposition furnace at a temperature of 250~350°C for 1-3 hours, and then put them into a salt bath for cleaning. A salt bath consists of a solution of sodium nitrite, sodium nitrate, and caustic soda. At high temperatures, sodium nitrate produces active oxygen with strong oxidizing ability, which oxidizes and decomposes polyester into carbon dioxide and water.
3. Triethylene glycol method
It uses the principle that polyester can be dissolved by triethylene glycol at the boiling point of triethylene glycol (285°C at normal pressure) to achieve cleaning purposes. The cleaning step is to put the object to be cleaned into a triethylene glycol tank with a heating system, raise it from room temperature to 265±5°C, keep it warm for about 6 hours, and then let it cool naturally to about 100°C. Take out the object to be cleaned, put it into a hot water tank at about 95°C and wash it for about 20 minutes, then soak it in a 10% NaOH solution at a temperature of 60-70°C for 12 hours, and then wash it with hot water. The triethylene glycol (TEG) cleaning method has the characteristics of low temperature, safety, non-toxicity, good cleaning effect, and no damage to the equipment.
4. High temperature hydrolysis method
This method uses polyester to be easily hydrolyzed and alkalinely decomposed at high temperatures to produce low-molecular substances, which can be removed. It places the object to be cleaned in an autoclave, passes in 0.3-0.6MPa steam, the temperature is about 130-160°C, and the time is 2 to 8 hours. In the autoclave, if a small amount of NaOH is added, the cleaning time can be shortened.
5. Alumina fluidized bed method
It puts the objects to be cleaned into the cleaning furnace, and uses compressed air to blow the electrically heated aluminum trioxide particles to form a bath bed with a uniform temperature in the furnace, which removes polyester, oil stains and organic matter on the objects to be cleaned. Rapidly decomposes at high temperatures to achieve cleaning purposes.
6. Vacuum cleaning method
The vacuum cleaning method is also called the vacuum calcining method. Working principle: The temperature is first raised to melt the polyester on the object to be cleaned and collected into the tank at the bottom. The temperature is raised again to cause the remaining polyester to begin to decompose, and a small amount of air is introduced at the same time to oxidize the residue. In a vacuum state, the residual polyester thermally and oxidatively decomposes quickly, and the gas and particles produced can be pumped away.
7. Ultrasonic cleaning method
Ultrasonic cleaner is a device that emits sufficient and powerful mechanical vibrations to the liquid bath. This device uses sound waves to achieve cleaning purposes. Sound waves cause cavities through the movement of the water bath, thus washing the surface of the object to be cleaned, releasing 103350Kpa energy to loosen and eliminate dirt.
Futai can customize various cleaning furnaces, ultrasonic cleaning machines and other equipment for cleaning spinning components, metering pumps, melt filters, spinnerets, and Leaf Disc according to customer needs. At the same time, we also produce spin pack filter, Shattered metal sand, Film filter disc, filter elements and other products. < https://www.futaifilters.com/ www.shfutai.com >
Post time: Sep-18-2024