Steam & Excursion > Tech question on the AC-9's

Just read in a post here that the Hancock injectors on the AC-9's gave the crews fits because noone knew how to operate them. What could've caused that to be a problem? Was there a solution?

apollo17 Wrote:
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> Just read in a post here that the Hancock
> injectors on the AC-9's gave the crews fits
> because noone knew how to operate them. What
> could've caused that to be a problem? Was there a
> solution?

Those Hancock Insperators were, reportedly NOTHING but problems!  For example, the C&O got so fed up with them, they removed them fro all the J3a class Greenbriers and replaced them with a second injector. Another problematic exhaust steam injector system was the Sellers system, used on the Union Pacific FEF class 4-8-4s. The UP even started up-grading their 4-8-4s to the Worthington S Feedwater System, as they were scheduled for overhauls.

As sometimes temperamental as the Elesco Exhaust Steam Injectors were, they were far easier to uses than those damned Hancock and/or Sellers systems.

HotWater Wrote:
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> apollo17 Wrote:
> --------------------------------------------------
> -----
> > Just read in a post here that the Hancock
> > injectors on the AC-9's gave the crews fits
> > because noone knew how to operate them. What
> > could've caused that to be a problem? Was there
> a
> > solution?
>
> Those Hancock Insperators were, reportedly NOTHING
> but problems!  For example, the C&O got so fed up
> with them, they removed them fro all the J3a class
> Greenbriers and replaced them with a second
> injector. Another problematic exhaust steam
> injector system was the Sellers system, used on
> the Union Pacific FEF class 4-8-4s. The UP even
> started up-grading their 4-8-4s to the Worthington
> S Feedwater System, as they were scheduled for
> overhauls.
>
> As sometimes temperamental as the Elesco Exhaust
> Steam Injectors were, they were far easier to uses
> than those damned Hancock and/or Sellers systems.

I'll be VERY interested to see how this thread develops.  And, in ANY other information you or anyone else can provide.  I'm attending the NSSR's steam forum this Saturday for it's newly restored 2-8-0 #28.  This engine has two Hancock Inspirators.  From what I've read, they should behave much like an Ohio?  No?  What's to make it give trouble?  What kind of trouble?  What's the remedy?  Any info I can share at this forum would be sincerely appreciated.

Or, did SP hoggers suffer the "Not Invented Here" malady?  Or, "We've never done it that way, before."

BTW, I have run mainline steam with an Elesco Exhaust Steam Injector, and LOVED it!  It had no bad temperment, even if you didn't talk to it nicely.  Performed like a dream, and easier to use and service than a Worthington feedwater heater.

-John

I'm not sure where the Coffin system falls in this subject.  I don't think there's anything running that I know of with a Coffin FWH.  Frisco was big on them.

I haven't used a Hancock anything on a larger engine, but I can tell you on relatively small engines I've used several Hancock inspirators in the #7-#9 range. They're a little trickier to start than a normal injector but once started they feed just fine and don't tend to break. I wouldn't characterize them as particularly troublesome at all. It's possible the larger ones were a different story.

There are a couple of distinctions between the Hancock devices.
For some reason, Manning, Maxwell and Moore ( Hancock) used the word "inspiratior" for the variant of the common injector .
i suspect that patent-protection wording was the inspiration for the trademark name....

Late in the development of the steam loco, Hancock marketed a varaiant of the exhaust steam injector.
It differed from their  other ( conventional) inspirators in mechanical complexity and in theory of operation.
they were intended to compete with  other-manufacture exhaust steam injectors, then in vogue...

They were mostly marketed as a cheaper replacement for the Worthington SA-series of feedwater heaters.
And yes, after being in service for a while, they became untrustworthy and very difficult to keep up.
I know of no extant versions that still exist, ----- maybe on a 'stuffed and mounted' engine somewhere.

Now back to the Hancock inspirator of conventional design....

in my experience theses are the MOST RELIABLE on loco feedwater injectors, bar none....
Hancock sold two variants, 'lifting' and 'non-lifting".  
I speculate that since the manufacturer seemed to be Canadian, that they were not widely applied to American built locos.

My experience has been with the CP locos of George Hart and of Nelson Blount.... the famous G5 class and Hart's CPRR class 
D-10,  4-6-0, Ten-Wheeler, number 972

Their major distinction, from conventional injectors, is that they separated the functions of an injector into two, isolated, Venturi jets ---- the lower jet sucks the cold water from the tender  and blows it into the 'forcing cones' of the 'second stage' ---- higher pressure region leading to the boiler check.

The separation of the two functions, in my experience, gives the Hancock superior boiler feeding characteristics, especially at low water-feed rates.   This is evident when you want to match the water fee- rate to the steam demand of the throttle.
The Hancock, with its separate water lifting jet,  can be 'throttled' way back, to just a trickle of cold water being fed.... The forcing jet runs full open, an rams the water, avaialbe, into the boiler.  This allows the 'gun' to left ON, while simply varying the water valve
( and jet) as the demands vary ---- comparable to a feedwater pump.

The second BIG advantage, is that the separate water feeding jet handles hottter feedwater much better than conventional injectors.
If the feed water gets too hot, applying a vacuum to the surface simply turns the water into steam, and not a liquid...thus, no suction can be formed.  This is very hard to solve with conventional injectors equipped with a single jet operating the 'lifting' and the forcing operations ---- in one injector body.

The Conventional Hancock Inspirator employs a very efficient little jet ( lifting) blowing towards the open overflow valve of the lifting function. The STRONG Venturi proportions are especially designed to expel air and steam, if any, out the overflow.
Very quickly,  the cooler water in the supply pipe is drawn into the lifting-jet and blown into the forcing region.

The operator simply opens the water Venturi until cold water flows out the overflow, then the operator open the steam valve completely, bringing the forcing function into play.  The injector body does not become overheated from the main steam jet blowing into a 'vacant' injector body, ---'vapor locked'--- until cool water is presented.   In my experience this has been virtually failure proof.  See the advantages of non-lifting injectors.

With conventional non-lifting designs, an overheated injector body can be cooled simply by opening the injector's water supply valve ---- water runs from the tender bottom to the, lower, injector body --- by gravity--- and coolis it down.  
Lifting injectors can be mounted above the water level of the tender, and raise the water by having the external atmospheric pressure force the water into the partial vacuum of the injector body interior.  Unless the water supply pipe has gotten hot ---- then applying a vacuum to the hot water simply causes the water to boil in the pipe,  account of the lowered pressure....

The genius of the Hancock design is the separation of the two functions -----into two separate Venturi 'proportions' and two separated section of the injector body casting.  The sucking Venturi is low pressure/ high volume design, the forcing section is high pressure/low volume design

Hancock, sold two versions: the non-lifting and the lifting styles.  The outstanding distinction from conventional injectors is the use of two, distinct, steam supply lines to the inspirator body. The smaller diameter steam pipe serves the "lifting Venturi" and the larger steam pipe serves the water-forcing function of the injector.

I highly recommend continuing in use the Hancock ( conventional ) Inspirator, if in place or even applying their device as an up-grade to a loco restoration.

AND, yes, avoid the "exhaust steam" variant, "like the plague .... "

​W.


​clunky spell -checker avoided and not grammatically corrected, yet

wcamp1472 Wrote:
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> For some reason, Manning, Maxwell and Moore (
> Hancock) used the word "inspiratior" for the
> variant of the common injector .

  They also used the name "inspirator" for their whistles.


> I speculate that since the manufacturer seemed to
> be Canadian, that they were not widely applied to
> American built locos.
>

 Manning, Maxwell & Moore was based in Bridgeport, Ct with production facilities in New York and Chicago.

So did the AC-9'c have lifting or non-lifting injectors? Anybody have a picture or drawing of one? Were they lever start or screw start?
 

We use the non-lifting variety of Hancock on the k36s and they are reliable and durable in service. They seem to work very well at higher altitudes which is also very necessary at 10,000'. When starting one needs to follow the procedure with patience, but once running they are very easy to throttle and keep running for miles.

Best,

Stathi

Posted from iPhone

According to Robert Church's bible on SP articualteds, the AC9's were built with "Hancock Turbo Feedwater Heaters". size TA-2.  It says they were hard to maintain and operate.  If the pump broke suction it would blow steam into the tender, heating up the water to the point where the injector would not pick up.  It further sttes that a #17 Nathan Simplex, was the second feedwater source.

Earlk Wrote:
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> According to Robert Church's bible on SP
> articualteds, the AC9's were built with "Hancock
> Turbo Feedwater Heaters". size TA-2.  It says
> they were hard to maintain and operate.  If the
> pump broke suction it would blow steam into the
> tender, heating up the water to the point where
> the injector would not pick up.  It further sttes
> that a #17 Nathan Simplex, was the second
> feedwater source.

Would converting them to the Worthington Feedwater system been better, or could it have been done with the AC-9's? 

Southern 630 has a lifting Hancock on the engineer's side.  It performs fairly well on the road, though it was almost always supplemented with the "big gun" on the fireman's side when running on the mainline.  You can trim it back and let it run during long periods of constant working, which often occurs when running up Missionary Ridge on the Summerville trips, but usually was wide open while the engine was running at (relatively) high speed on NS.