Re: 464

I mentioned that above. Tractive effort does not change. TE is simply steam pushing against the pistons. Makes no matter if it is superheated or not. The differece becomes when underway, the superheated steam has much more potential energy and has much greater expansive properties, more work can be done with less steam, thereby reducing water consumption. The less water you use the less fuel burned to boil it to steam - everybody wins.

A superheated K-27 has the same 27,000 pounds of T.E that a saturated one has as the cylinders are the same size. As a compound, I think starting in compound, using the high pressure pistons to get underway, I they developed around 25,000 lb. T.E. as the steam was pressing against the smaller high pressure piston only. In simple, the high pressure cylinders are bypassed and the live steam flows directly into the low pressure cylinders, which are much larger. I've never figured this tractive effort, but it could be done easily if one has the cylinder size of the low pressure cylinders. I'm guessing this T.E. could be pushing 30,000 lbs. Remember the engineer was only supposed to start the train moving in simple and then change over to compound as soon as possible. This was a problem, because appearently the engineers like to leave the engines in simple too much.