Boiler Or Steam Generator? We Break It Down For You

A steam generator is equipment whose function is to produce steam. In this sense, the boilers are nothing but steam generators. In the usual industrial language, however, it is customary to designate “commercial steam generators” for steam generators with smoke tubes and steam generators or generators water.

So there are two major families of steam production equipment. The purpose of this FAQ is to explain the difference between these two families and to highlight the main advantages and disadvantages of these.

A steam generator necessarily includes one or more burners whose flame and fumes are brought into contact with tubes through which heat is transferred to the food water to produce steam. Constructively, there are two possibilities: either the flame and the smoke circulate inside the tubes, or it is the water that circulates in them. In the first case, the term “steam boiler with flue tubes” is used, in the second it is called “steam generator with water tubes”. In both cases, the tubes function as those of a gas — water heat exchanger (+ steam). Of course, a room of larger volume must be reserved for the development of the flame. A part of the generator is therefore reserved for the flame whereas a second part is reserved for the prolongation of the heat exchange between the fumes and the water.

In a flue gas boiler, the combustion gases circulate inside the tubes while the water surrounds them. The assembly is confined in a large ferrule which constitutes the cylindrical body of the boiler. These generators are also called “boilers with internal fire” or “boiler”.

Commercial steam generators are nothing but water-tube boilers. Unlike flue-gas boilers, the generators are constructed in such a way that the water circulates inside the tubes and not the fumes. In the small and medium industry, generators are more commonly found capable of producing up to twenty tons of steam per hour.

The main advantage of commercial steam generators on boilers is that they can respond very quickly to sudden changes in the demand for steam. Therefore, they are better suited to productions that stop and restart daily, for example. For the rest, it is necessary to consider point by point what really constitutes an advantage or a disadvantage in the specific case that arises. For example, if there is little space on the ground and the ground does not support a heavy load, the generator could impose itself automatically.