All,

Does anyone have any documentation on or point me towards the best archive who would have info on the Hancock Turbo Feedwater Heater produced by the Manning, Maxwell & Moore company? Particularly the type TA-2. Were there any instruction pamphlets produced (like the ubiquitous WABCo ones)?

I have found little information besides the basic description of how it functions and the reference from second hand sources that they performed poorly.

So far I have the ad in the 1947 Locomotive Cyclopedia on pages 364-365, the PRR T1 test plant report and the patents US 2151125 and US 2235557.

Besides the PRR T1, the C&O J3a and N&W Y6 locos used them. I did just order the basic drawings for the Hancock FW heater on the Y6 from the N&W historical society. I'll be contacting their historical societies (C&O and N&W).

Thanks,
Joe

This is the best I can come up with. Good luck.

Last page.

New Haven's 10 I-5 4-6-4s of 1937 had them as well. Hancock was an on-line NYNH&H supplier; the turbo-FWH had some problems on the I-5s-- not being able to supply enough water at full working capacity of the boiler. And the water delivered was not as hot as that supplied by a "regular" FWH, such as Elesco.

Howard P.

Golly that is complicated!

Adam Phillips,

Thanks for the scans. What publication did the come from?

I'd like to upload the 1947 Loco Cyclopedia ad, but the 350 KB file size limit makes the pictures rather unreadable.

Howard,

The Hancock turbo feedwater heater had the range of capability to deliver from 4500 to 13,000 gallons per hour depending on the model (TA-1 and TA-2). Also, on the PRR T1 tests it delivered the feedwater up to 250 degrees F, with most tests around 230 degrees F which is identical to the Worthington SA. Do you have any further info? Did New Haven mismatch sizing?

Joe

Joe, that info was from the Railway Maintenance series by the American Technical Society.

These are from the Cyclopedia.

Good luck with your project.

Joe,

New Haven info is from Art Bixby, NH mechanical dept engineer (later with N&W and retired from N&W), via Jack Swanberg. Apparently, when the engines were working to capacity, the TFWH couldn't keep up with evaporation. Any actual data? I doubt it, so many years later.

Howard P.

I wonder how well the N&W Y-6 Hancock installation worked (if they actually did it)? It must have been a one-off/trial installation, because Y-6a's had Worthington BL's and Y-6b's had Worthington SA's.

You can find quite a few drawings for interesting steam experiments in the N&W Historical Society archives.

The Hancock feedwater heater was a little complex, but it was designed to switch automatically between exhaust steam from the cylinders and live steam for heating the feedwater. The pump could then be run continuously to match demand. The exhaust steam from the turbine was fed to the condenser to heat the feedwater. The advantage of the three-stage centrifugal pump was that it eliminated the pulsating effect compared to reciprocating pumps. The turbine and four pump impellers were mounted on a single shaft for simplicity.

**Edited calculations below:

To give you some actual numbers on its performance below is data from the PRR T1 test plant report for test #1438. The PRR T1 used the Hancock TA-2 Turbo Feedwater Heater, which had a capacity of 108,300 lbs/hr or 13,000 gallons/hr. Some assumptions had to be made due for calculations to lack of information.

During test 1438, total boiler evaporation was 95,233 lbs/hr or almost 90% of the maximum capacity for the feedwater heater system. The turbine was fed 4943 lbs/hr of live steam and the exhaust steam from the cylinders was 10,020 lbs/hr. The condenser condensed a total of 14,963 lbs/hr of exhaust steam (from turbine and cylinders) to heat 80,270 lbs/hr of water from the tender. The feedwater temperature was raised from 49°F to 235°F. Heat saved by heater as a percent of coal fired was 5.2%. Water condensed from cylinders and returned to boiler as a percent of total evaporation was 10.5%. The turbine did consume 5.2% of total boiler evaporation.

Based on total dynamic head power calculations, the pump used 11 horsepower to pump the cold water from tender to the condenser (atmosphere to 90 psig) and 43 horsepower to pump the hot water from the condenser into the boiler (18 to 311 psig). Each pump impeller/stage produces a 90 to 100 psi increase in water pressure. The cold water pump is single stage and hot water pump is three stage.

Total shaft power developed by the turbine is 55 horsepower including friction loss. The turbine-pump performance was similar to an injector in that only about 3% of the heat in the steam fed to the turbine was converted to shaft horsepower for the pumps or lost. The remaining 97% of the heat in the steam fed to the turbine is used to heat the feedwater from the tender.

Assumed:
1. Single Stage Turbine is 65% efficient (calculations later showed about 75%)
2. Centrifugal Pumps are 80% efficient
3. Condenser Pressure is 18 psig
4. Pressure of Cold Water Leaving Pump to Condenser is 90 psig
5. Final Pump Pressure to Boiler Check is 311 psig
6. Heights Above the Rail:
a. Pump Centerline 48 in.
b. Condenser 90 in.
c. Boiler Check 180 in.

For Test 1438:
1. Boiler Pressure: 296 psig
2. Exhaust Steam from Turbine at Condenser: 18.3 psig, 256°F
3. Exhaust Steam from Cylinders at Condenser: 18.7 psig, 359°F
4. Water in Tender: 49°F
5. Atmospheric Pressure: 14.3 psia

That is some INCREDIBLY high back pressure! Even with the installation of a NYC exhaust diffuser I have been able to reduce back pressure to about 9-10..

Regardless, that is an exceptionally complex system. My impression had been that they tried to go a good thing.... in a manner that gets around the Coffin patents.... but it was just a touch too sensitive to be conducive to the average railroad environments.


Cheers, Jason

Are you referring to the high back pressure for the turbine or the cylinders? In operation the turbine exhaust back pressure will have to match the cylinder back pressure at the condenser, as both streams of exhaust steam are condensed to heat the tender feedwater. The T1 had too high cylinder back pressure which has to be redesigned.

I agree that the Hancock system does seem to be an attempt to get around some of the other patents while introducing new operating characteristics or features.

Based off the descriptions from Adam Phillips, I'll have to revise the calculations since I underestimated the final pressure from the cold pump to the condenser nozzles. Will edit the post when I recalculate.

Joe