Brake Horse Power
- This is the useful power available at the flywheel of an engine. Nowadays engine power is often quoted in PS. 1PS=0.9863bhp.
- It was first used by the engineer James Watt, who employed it to compare the power of steam engines with that of horses. In the UK, one horsepower is equal to 550 foot-pounds per second or 745.7 watts. In the USA this figure has been rounded to 746 watts, and in the metric system it is 735.5 watts.
- Conversions
1 BHP = 745.7 Watts 1 BHP = 33000 ft lbf min-1 1 BHP = 1.01389 PS 1 BHP = 42.41 BTU min-1
- Examples
pushing or pulling horizontally1 0.097 BHP treading a machine1 0.09 BHP winding a crank1 0.081 BHP hand lifting 20kg1 0.045 BHP Digging a trench1 0.014 BHP - It was first used by the engineer James Watt, who employed it to compare the power of steam engines with that of horses. In the UK, one horsepower is equal to 550 foot-pounds per second or 745.7 watts. In the USA this figure has been rounded to 746 watts, and in the metric system it is 735.5 watts.
- Note 1 based on a man in good health working for 8 hours per day
See also: Friction Horse Power, Indicated Horsepower, Indicated Mean Effective Pressure, Mechanical Efficiency, Power, RAC Horsepower Rating, Shaft Horse Power.
Subjects: Automotive Mechanical Engineering