Design And Realization Of A Novel Automatic Glycerol Spray System

Filter rod production is an important process of filter tip cigarette production. In the filterrod production process, filter rod hardness was a key technical indicator affecting the quality ofcigarette. Therefore, filter rod hardness must be controlled effectively. General method of controlfilter rod hardness was coating plasticizer glycerin to the surface of tow cellulose acetate. But inthe traditional way glycerin was coated to tow surface by glue brush rotating centrifugal force.Glycerol was the form of small droplets, and it is difficult to achieve uniformity of glycerolspraying and waste a great deal tow and glycerol.In order to improve the quality of filter rod, it was necessary to control the glycerol sprayflow rate in real-time, which was synchronous with the tow speed. It maintained the glycerolspray flow rate on unit area stable tow. As a result, a new automatic glycerol spray system wasresearched and designed based on glycerol spraying technique.In the system glycerol spraying technique was used to replace traditional brush glue method,and "PLC+touch screen" was regarded as the electric controller. The system included mainlyPLC, touch screen, servo amplifiers, servo motors, AD modules, booster pumps, glycerol boxes,the main heater, oil, nozzle, pre-heaters, valves and various sensors, etc. The followingfunctions were included:(1) Glycerol spraying and flow regulation: High-pressure spraying method was used.Glycerol in glycerin box was pressurized pump nozzle through the booster pump. Under a stablepressure Glycerol was sprayed evenly on the tow by the nozzle pre-heating. Positioning functionof the PLC and servo positioning module was utilized to control valve position and regulateglycerol flow rate in real-time, according to the tow speed.(2) Automatic glycerol heating and fuel: According to the upper and lower temperature,automatic heat was used to work for glycerol at the best temperature range by detecting glyceroltemperature in the glycerol box. Detecting glycerol float switch, fuel solenoid valve was used tocontrol the process of automatic refueling.(3) The fault diagnosis and position: According to the temperature, pressure, and binarysignals, a variety of system faults was determined, positioned and processed to guarantee for thestable and reliable operation.(4) The maintenance functions include: pump system testing, switch valve, the glycerolspray rate curve as well as the factory settings. (5) Man-machine interface: The touch screen was provided for a friendly man-machineinterface, which completed data and status display, parameter settings, and the data exchangewith PLC.The system was tested fully under the different speeds. The testing results show that thesystem can tracking machine speed in real-time, and can adjust automatically the glycerol sprayrate. It proves a tow glycerin spray evenly on the unit area and filter rod hardness compliance,and improving the effectiveness of filter rod production, equipment stability and reliability. Itpossesses high practical value.