Research On High-temperature Heat-insulating Coatings For The Electromagnetic Dryer

Electromagnetic dryer is a new kind of paper drying equipment. Due to that the electromagnetic dryer is of high efficiency, low operation cost and high energy utilization, electromagnetic dryer belongs to the environment-friendly equipment, which makes electromagnetic dryer has wide application prospects in paper making industry. Because electromagnetic dryer needs to work continuously at a high temperature environment, it easily leads some electric connection damaged, which is a security risk and worthy of attention. In this paper, a kind of high-temperature insulation coatings is studied. The coating would be coated on the internal surface of electromagnetic dryer, which could be effective to resist heat to transfer to the internal part of the dryer. In this case, the hazards said above could be avoided. The specific work and the main results of the article include the following parts:1 Firstly, the methyl phenyl silicon resin was synthesized. Methyl thichlorosilane, dimethyl dichlorosilane, phenyl trichlorosilane and dichloro-diphenyl-silane were used to synthesize methyl phenyl silicon resin. It was studied that the effects of different factors on the synthesis of silicon resin. The best conditions to synthesize silicon resin are that: R/Si value is 1.55, Ph/R value is 0.4, the stirring rate of hydrolysis is 300r/min, stirring time is 30min, water content is 80%, the vacuum of condensation reaction is 0.08~0.09MPa, time of polycondensation is 5h, and the amount of catalyst is 5% of the total mass of resin monomer.2 A kind of high temperature silicone coating for electromagnetic dryer was studied. The high temperature insulation coating was made by choosing the appropriate pigments, fillers and diluent, and grinding them at high speed. It was studied the content of pigment and fillers. The results shows that when the proportion between the silicone resin and mica powder, aluminum powder, zinc phosphate, titanium dioxide and kaolin mass is 10:5:2:1:5:2, the coating reached the highest temperature. Through high temperature testing, the high -temperature coating can keep its performance after working 1h at 350℃; and, the heat insulation effect is not effected if the coating work at 250℃for 28 days.3 The study on the curing system of the coating is carried out. The curing agent is made by using cobalt naphthenate, triethylenetetramine as the curing agent, which added tetrabutyl titanate as a cross-linking accelerator. When the mass ratio between cobalt naphthenate, triethylenetetramine and tetrabutyl titanate was 1:2:2, and the mass ration between coating and curing agent is 8:1 to 9:1, the curing system shows the best curing effect.4 The simulation application of high temperature insulation coating on electromagnetic dryer. By using ANSYS software, the finite element analysis about the application of using high-temperature resistant coating on electromagnetic dryer is carried out. The thermal analysis results show that the high temperature coating made by the experiment could be effective in insulation.