2 replies to this topic

[Ghasem.Bashiri]

I want to select a boiler. My required pressure is between 15 to 20 Barg.
With 10-20 C superheat.
Also my required flowrare is between 3-8 ton/hr.
Actually I need to know is there any envelope in Pressure and Flow for selection of boiler? I mean water tube or Fired Tube Boiler.
I need this boiler for start up of my plant under design.
Therefore I have some range for selection and design.
Ghasem Bashiri

[djack77494]

Ghasem,
My suggestion is that you contact boiler menufacturers to get your answer. You might find a manufacturer that makes both types of boilers. If so, feed him your requirements and he'll probably respond with the best choice. Lacking that, contact 2 or more boiler makers. Likely, the maker of the optimum type will respond quickly and positively; the maker of the less suitable type of boiler will probably request clarifications and offer suggestions for you to change your requirements (e.g. use multiple boilers when you had one in mind, etc.) If not, you'll get quotes for each type and can see at least the financial benefits of selecting one type or the other.

Practically, a large volume of hot pressurized steam is contained within the boiler. In a water tube boiler, the bulk of the steam/boiling water is contained in pipes. in a firetube boiler, it is contained inside a vessel. The firetube is a good choice for small boilers and a poor choice for large boilers.

You are probably a very smart, motivated engineer. But you are not in the boiler design business, so please don't try to design a boiler. Your boiler design either won't work, won't be safe, or will cost much more than it should and lack essential features.

Edited by djack77494, 25 August 2010 - 03:05 PM.

[Art Montemayor]

Ghasem Bashiri:

Presumably you want to decide what type of boiler to specify for purchase.

For 20 barg of working pressure, with superheat, and a capacity of 8,000 lb/hr I believe you are already in the class of a water tube boiler. This is a robust, rugged, process design type of boiler with good operting flexibility and turn-down characteristics.

A fire tube boiler is meant for much smaller service and usually for small working pressures: 35 - 75 psig and no superheat. It is primarily a commercial machine meant for launderies, heating plants, hospitals, hot water, etc.