Boiler horse power is about 42,000 BTUs of INPUT
One pound of steam is about 1,200 BTUs of INPUT fuel, and about 1,000 BTUs at the point of use, depending on the pressure of the steam
Low pressure steam is considered to be up to 15 psi, high is generally 100 psi and higher.
Superheat is a term that refers to higher temperature steam, as a result of a second special steam heat exchanger in the boiler that allows steam pressure to increase, thereby taking on more BTUs (in excess of 500 psi is typical of superheat). Superheated steam is very dry steam.
Smaller boilers are generally rated in horse power; larger are generally rated in thousands of pounds of steam (500 HP and under will typically be rated in HP)
Typical boiler efficiency will be in the 75 – 85% range new highest efficiency boilers may be near 90%; newer quick heat up types of boilers with copper heat exchangers can be more efficient, especially at start up and part load than older, heavy mass cast iron boilers.
Fire tube boilers are often characterized by their number of passes, referring to the number of times the combustion (or flue) gases flow the length of the pressure vessel as they transfer heat to the water. Each pass sends the flue gases through the tubes in the opposite direction. To make another pass, the gases turn 180 degrees and pass back through the shell. The turnaround zones can be either dry back or water-back. In dry back designs, the turnaround area is refractory lined. In water-back designs, this turnaround zone is water-cooled, eliminating the need for the refractory lining.
Steam boilers which are mainly used in process industries fires, wood or coal as fuel depending on the availability of fuel in the local area.
Maxtherm Boielrs has supplier of wood/coal fired boilers for various industries such as chemical, packaging, sugar, etc. maxtherm Boilers has supplied boilers of capacity variying from 0.5tph – 20tph. Depending on requirement these boilers are designed with single or twin furnace.
Duo Block Boilers are also a combi type boiler consisting of a furnace, water wall arrangement and a shell and tube boilers. But the difference is the space it occupies is less compared to a combi boiler because the shell and tube boiler is placed above the water wall structure. So for the same capacity, the total area occupied will drastically come down.
Combitube boiler is combination of Shell and Tube Boiler and Water tube boiler with external furnace.
