From his calculations the expected power required to turn the loaded vessel is 0.2hp (see Document-161943, p3).  The higher figure of 0.4hp in his final recommendations comes from the power rating of a 40 tooth sprocket (the driver sprocket) with a No. 50 roller chain operating at 10rpm (the lowest speed shown on the table) - meaning this driver sprocket arrangement can handle up to 0.4hp.  We discussed this on the phone on January 4th and agreed that a 1/3hp motor could be used which will match the reducer Alejandro selected, and will supply sufficient power given that calculations indicate only 0.2hp is required.

 

Once the vessel is installed in the shield box a test will be performed to determine the actual torque (and power) required to turn the vessel.  If the value differs significantly from the calculated value the design will be revisited.