I was regretting not ordering the Club anniversary 37020 freight steam locomotive with a condensation tender. Then I looked at my Marklin engines (temporarily in storage) and discovered I have a 37023 loco whose engine looks identical to the 37020 except the tender is not a condensation tender with the fans etc.

Any of you have the 37023 and opted to order the anniversary model (37020)? If so, what were your reasons?

What is the purpose of the condensation tender, how does it compare to the conventional tender and did it fall into disfavor for some reason?

Thanks,

Larry

Yikes! Why did we need a Thayls if steamers can go that fast?

Thanks, Tom, for sharing your great insights. I greatly appreciate it.

Larry

This was done on the main lines in the UK as well, and I always thought the idea was very cool. It works by having a trough between the rails full of water, and a scoop under the tender that can be lowered into the trough. As this is done at speed the water is scooped into the tender under considerable pressure, filling it in seconds.

It must have been spectacular to see!

Condensing tenders were developed during World War 2, by Germany for use in Russia where there were problems with adequate water supplies. The exhaust steam is diverted back into the tender where it is passed through an array of tubes, cooled by air fans. In place of the steam exhausting up the chimney a fan provided the draught to the fire. This could cause problems with steaming as the automatic feedback between the rate of working and the amount of energy being produced is lost. As a normal locomotive works harder, more draught is generated in the smokebox which increases the rate of combustion. On top of which of course is the greatly increased weight and complexity of condensing tenders.

Around London, condensing tank engines were used in tunnels. However here the steam was simply diverted into the side tanks. Eventually the water would get so hot that the injectors would stop working. At that point the water in the tanks would be dumped and replaced with cold water.

Bob M.

With all steam ships and power plants having condensors, I would have thought they had the problem of corrosion sussed. I suspect that the problem on applying them to locos was that tenders tend to vibrate and jerk, stressing parts of the condensor, and the sheer weight of it all. Any extra weight in the tender you add means less tonnage and therefore money you can move. The artificial draught is a problem as well, how to get the draught going without excessive wear on the machinery. Also, it may seem odd, but the pulsing draught makes a steam boiler steam much better than a continuous draught.

My two cents worth,
Rick

Couldn't there have been problems also in winter sometimes?

I guess there is a reason why this method was never used in Sweden.

Think: Temperature below 0 C or 32 F.