I recently acquired an Ashcroft, German-style, diaphragm gauge that is installed in a metal box. When I received it, I discovered that the well-worn label in the cover of the box described it as a “Test Instrument or Changeover Device of Elesco Exhaust Steam Injectors.” I then located a reasonably priced copy of the instruction manual for the device at an on-line bookseller. After ordering the book, I received a note saying that it had been lost, and refunding my money. There is another copy available, but it is priced at much more than what I paid for the gauge.

Does anyone here have a simple explanation of how this device was used?

(In the early 1850s, a company in Cincinnati was making German-style diaphragm gauges for use on locomotives. I don't believe that many gauges of this design have been manufactured in the last 70 years. Not many were used for steam service since the late 1800s.)

Bruce E. Babcock

I could swear I'd seen a detailed technical answer to this question.

I don't have the detailed information, but I believe John Rimmasch will. In the meantime, look here:

https://books.google.com/books?id=EY3pAAAAMAAJ&pg=RA13-PA22&lpg=RA13-PA22&dq=elesco+ES+exhaust+steam+injector&source=bl&ots=II4Vk1sHxJ&sig=x4putlTclGBHCARChttWaLkRYWc&hl=en&sa=X&ved=0CEQQ6AEwB2oVChMIo6yokZeVxgIV0iyICh0taQkp#v=onepage&q=elesco%20ES%20exhaust%20steam%20injector&f=false

Note that the system is calibrated to use exhaust steam at circa 1 psi. I suspect your device is to be used to adjust the modulating valve which provides this pressure. Presumably you would use a bulb or hand pump to apply pressure to the valve until its steam port is observed to open correctly, then bleed off pressure to observe that it modulates correctly.

This would explain the relatively low range, but fine calibration, centered around 1 psi, of the gauge you have.

While an engine is hot, you could connect this device to substitute for exhaust steam to operate the diaphragm which controls the pin valve.

Any of these exhaust steam injectors in service now or recently?

The Soo Line 1003 operating out of Hartford, Wi. has one that has worked quite reliably. mld

See attached pictures for the description of how and why this test instrument was used on the Elesco exhaust steam injectors. It's main purpose was to test the diaphragm valve. The pictures are from the Elesco operation and service instructions for Type T Injectors, Bulletin 5700-4, dated June 1941. The test instrument has it's own separate bulletin, which I also have. PM me if you want the pdf files.

UP's 3985 and 4014 utilize the Elesco TP exhaust injector system. You can see the exhaust injector under the running board on the fireman's side of the smokebox.

Hope that helps,
Joe

Although neither of them are running now, both UP 3985 and Jerry Jacobson's GTW 4-8-4 have Elesco exhaust steam injectors.

IF 4014 runs again, it also has an Elesco exhaust steam injector. Both it and 3985 have the Elesco model TP. Don't know about JJJ's engine.