Stuff You Should Know Relating Boiler Horsepower to Steam Output D.E. McConnell Technical Stuff and not so technical stuff you should know to do your job

Stuff You Should Know Piedmont Carolina Section 2 Stuff You Should Know A series of short vignette teaching tools to illustrate important technical concepts and procedures you need to know to do your job well. These vignettes can be purely technical calculations, learnings from a troubleshooting experience or failure, or advice on how a specific problem was solved. Each vignette consists of no more than 5 slides with narration illustrating the concept, problem, or procedure and references It is hoped these will become a basic toolkit for engineers to solidify their knowledge or aid them in solving a problem

Stuff You Should Know Piedmont Carolina Section 3 Relating Boiler Horsepower to Steam Output Boiler Horsepower is a term used to rate fire-tube boilers in several countries including the United States. One should always be aware of the context when one sees “BHP” Fire-tube boilers fire into a large, generally tubular firing chamber and water circulates around this chamber. The hot flue gases then pass through multiple “ fire-tube ” passes, up to 4, before exiting. Water circulates around the outside of the horizontal firing chamber and firetube passes and boils

Stuff You Should Know Piedmont Carolina Section 4 Relating Boiler Horsepower to Steam Output “Boiler Horsepower” comes from the early days of boilers and steam engines 34.5 pounds of steam at 14.7 psia if condensed in early steam engines would yield about 1 horsepower. 1 BHP =34.5 pounds of steam Saturated Steam at 14.7 psia Saturated feed-water at 212 Deg F Fire-tube boilers are generally used at pressures less than 300 psig. High pressures, typical of power boilers are not suitable for fire-tube boilers Large diameter of shells limits the maximum pressure of fire-tube boilers Safety becomes a key concern as pressure increases. Catastrophic failures can turn fire-tube boilers into rockets How do I relate boiler horsepower to what a fire-tube boiler will really generate at any pressure.

Stuff You Should Know Piedmont Carolina Section 5 Relating Boiler Horsepower to Steam Output Knowing Boiler HP, it’s conversion, and the standard conditions will allow one to calculate the energy input to the steam in the boiler NOTE! This is NOT the energy input to the boiler! Blowdown is typically given or calculated as a % of feedwater flow, so m feedwater m blowdown m steam Marmaduke says….. “BILGEWATER! You should know this comes from a heat and mass balance on the boiler!!! BILGEWATER! “

Stuff You Should Know Piedmont Carolina Section 6 Relating Boiler Horsepower to Steam Output m feedwater m blowdown m steam Worked Example