glass heaters.

.glass heaters are generally available in tow major categories; Coil type and Shell & Tube type. Like any other Heat Exchangers, they can be used for variety of Shell & Tube type. Like any other Heat Exchangers, they can be used for variety of applications, namely, Condensation, Cooling, Heating, Boiling and suitable combinations of the above. The selection of equipment depends upon the type of application, heat load, availability of heating/cooling media etc.

In all types of glass heaters the heat transfer is through the wall of the glass tube. The heat transfer co-efficient can be of a moderate order because of low wall thickness. With 1.5 mm thick walled tubes, the wall heat transfer co-efficient is about 725 Kcals/hr m2 °C and we can obtain an overall heat transfer co-efficient for steam condensation with water cooling as about 550 Kcals/hr m2 °C.

the allowable pressure inside the tubes can be vacuum to 3 kg/cm2 while that on the domes as well as on the shell depends upon the size of the shell corresponding to the values mentioned in Technical Specifications. The Heat Exchangers can safely be used up to 200°C with the limitations of Thermal Shock up to 120°C and temperature gradient across the wall less than 50°C.

The shell side pressures on Metallic Shell & Tube heat exchangers can be as high as 2.5 kg/cm. For higher pressure requirement up to 4 kg/cm2 , the PTFE tube sheets need redesigning and can be made on special request.