Uploaded October 2020 | Updated September 2026, 15 hours ago
Indicating the 2,500 Horsepower triple expansion steam engine on the WWII Liberty Ship "Jeramiah O'Brien".
The final step in the process that isn't shown is to use the drawn graph to calculate the average pressure within the cylinder (P) during the up and down stroke. That will go into the P.L.A.N. formulae where HP=PLAN/33,000
Indicated Horsepower=PxLxAxN divided by 33,000 (the number foot pounds per minute determined by James Watt)
P= Pressure (average in pounds per square inch PSI)
L= Length of stroke in feet (up and down = one revolution. i.e. 3" stroke up and down = 6" or 0.5ft)
A= Area of the piston in square inches
N= Number of strokes per minute
This process is done so the engineer can adjust the valves to balance the horsepower on the up and down stroke of the cylinders. It is also done to balance between all cylinders on multi-cylinder engines (in this case a three-cylinder triple-expansion) to ensure they are all making the same amount of horsepower.
To learn more about the S.S. Jeramiah O'Brien, visit:
ssjeremiahobrien.org
To learn more about Steam Boats, visit:
http://www.thesteamboatingforum,net/forum/
steamboatassociation.org.uk
northweststeamsociety.org
http://www.steamboat.com.au/
spiretech.net/~artemis/NASAhome.htm
NOTE! this video or audio may not be reproduced or sampled without my express, written permission. Top 10 lists and other compilations are not "fair use"! More information on copyright and fair use as related to YouTube: goo.gl/8NDLUV
Filmed and narrated by my father, Steven Harcourt, and uploaded with his expressed permission.
Indicating the 2,500 Horsepower triple expansion steam engine on the WWII Liberty Ship "Jeramiah O'Brien".
The final step in the process that isn't shown is to use the drawn graph to calculate the average pressure within the cylinder (P) during the up and down stroke. That will go into the P.L.A.N. formulae where HP=PLAN/33,000
Indicated Horsepower=PxLxAxN divided by 33,000 (the number foot pounds per minute determined by James Watt)
P= Pressure (average in pounds per square inch PSI)
L= Length of stroke in feet (up and down = one revolution. i.e. 3" stroke up and down = 6" or 0.5ft)
A= Area of the piston in square inches
N= Number of strokes per minute
This process is done so the engineer can adjust the valves to balance the horsepower on the up and down stroke of the cylinders. It is also done to balance between all cylinders on multi-cylinder engines (in this case a three-cylinder triple-expansion) to ensure they are all making the same amount of horsepower.
To learn more about the S.S. Jeramiah O'Brien, visit:
ssjeremiahobrien.org
To learn more about Steam Boats, visit:
http://www.thesteamboatingforum,net/forum/
steamboatassociation.org.uk
northweststeamsociety.org
http://www.steamboat.com.au/
spiretech.net/~artemis/NASAhome.htm
NOTE! this video or audio may not be reproduced or sampled without my express, written permission. Top 10 lists and other compilations are not "fair use"! More information on copyright and fair use as related to YouTube: goo.gl/8NDLUV
Filmed and narrated by my father, Steven Harcourt, and uploaded with his expressed permission.
