A steam boiler is widely used in paper industry for heating purpose. Steam boiler cause a lot of energy lost and pollution problem, nowadays, more and more paper factory replace the steam boiler with thermal fluid heaters. Paper machine is heated by a thermal oil cylinder which composed of cylinder, bearing block, drive gear and chain wheel. They are connected and work in a closed loop circulation. Heat exchange tubes are installed uniformly in the cylinder. Thermal insulation materials are filled in the cylinder to provide thermal resistance . Thermal oil heating system features in simple structure, low cost, no leaking oil and stable temperature. It will be more and more applied in paper industry with no doubt.