Steam shovel

You can see on this freeze-frame the two cylinder unit with inlet pipe from the boiler and the outlet pipe running up the boom like we are discussing. Looks like the "exhaust" stroke pushes used steam into the pipe so there would be a constant flow while the unit was running? More than likely double acting cylinders so they would be pressurising on one side and venting on the other each stroke both up and down making the steam flow from the pipe almost continuous.

Some have the continuous flow exhaust directed out the back or through the cab roof instead of up the boom.

In the first video of the pair above post 247396 the third shovel shown clearly demonstrates the boom vent is exhaust from the boom arm engine. It is a direct drive power on demand and stops and starts as required with subsequent "puffing" exhaust. Most of the others are continuous motion with clutch engagement giving constant exhaust steam flow.

theabundantlife wrote:

Anyone else here young enough to have grown up with Bill the Steam Shovel? :whistle:

Certainly remember, but had no idea at the time that it was Ted Bulpitt! (Ross Higgins) (at least it sounds like him)

Jarrod.

Mammoth and Lang are onto it.

There are a couple of "high speed quick reversing" steam engines on the boom for a couple of functions such as running the arm in and out etc. These engines usually exhaust at the top to keep the steam from blocking the operators view. These are relatively small engines in botr and stroke (for a steam engine) and don't have a flywheel. They have a pinion on the crankshaft that runs on a rack on the arm they control and use the inertia of the arm and their speed to smooth their operation. There were a couple that came off a scrapped digger in operational condition in the Puffing Billy Museum when I used to volunteer there. The advantage of that was that you could see it in operation as it was at waist level, not 20 or more over your head