Heating rolls nowadays are widely used in our country, mainly focused in printing, compounding, papermaking, spinning and weaving, pressing and polishing, electronics, automobile, medical, solar energy, module pressing, food and beverage packaging, metallurgy, battery, nano-carbon fibre and other related industries. Heating ways of rolls are mainly about oil heating and steam heating, another way is heating by electric resistance; for example of oil heating, the highest usage temperature is no more than 180’C which limit the roller working temperature. Generally speaking, rollers surface working temperature is about 30’C-40’C lower than the heating oil, if you raise the oil temperature stubbornly, the oil will be oxidized to be scab on the inner of rollers which will lead the unhomogeneity of the temperature. Even use the best composed oil, working temperature of the roll is still hard to achieve higher than 250’C. In addition to that, the leakage of the revolving connecting arose by the heating oil will lead to the working environmental pollution and do harm to people, even will cause a fire. Over a long period of working time, fittings of the oil heating roll are easily damaged, and hard to change, besides that, the volatilization of the heating oil will affect the high quality of products which are not qualified. Therefore, in medicine, food, precise electronic products( such as liquid crystal manufacturing), valuable tickets and other industries, people always use electromagnetic induction heating roll achieving 400’C working temperature which can avoid the above mentioned problems, not only solve the oil leakage but also decrease the energy cost. However, owing to the high technology, the price of electromagnetic induction heating roll is higher than others which many factories cannot bear it. There are very few companies can manufacture this kind of rollers currently in the world. In china, even few companies can be counted on one’s fingers can produce high quality rollers, Shanghai Doreliance is one of them which can produce the most stable electromagnetic induction heating roller in the best price within the most comprehensive technology!