Convection heating is an excellent method of providing low intensity heat energy to a process medium. This heating
method provides for even temperature distribution across an entire coil surface. Common applications include regeneration gas heating, natural gas heating, air heating, ammonia heating, heating of temperature sensitive stocks (ie: cooking oil, crude oil, asphalt, etc.), thermal fluid heating, steam superheating, and many others. Due to the nature of convection heating, combustion chamber temperatures are tightly controlled, and tube wall temperatures are kept to a minimum. Heat up and cool down times are negligible, and burner control can be process-based or heater-based for cyclical operations. GTS convection heaters can be manufactured to meet virtually any code requirement, including ASME, API, USCG, ABS, etc.
So what’s wrong with radiant heat transfer? It can be advantageous in some systems; however, many processes demand a gentle and even introduction of heat. Radiant transfer can be easily illustrated by standing in the sun and then promptly moving to a shady area. It is easy to understand how radiant energy is very "line of sight" oriented. Inside a heater, it is impossible to insure that every inch of coil surface has the same exposure to the radiant energy. The result is uneven heat transfer, from which hot spots develop in the coil. These hot spots can damage temperature sensitive process mediums and significantly reduce tube life.