Erie Triplex

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Erie Triplex
Posted by mdtell on Wednesday, February 06, 2008 8:13 PM

Does anyone have any pictures of an Erie Triplex working with train that they can post?

Were the Triplex lights ever converted to electricity, and if yes, where was the generator placed on the locomotive.

Can anyone identify the function of the following details on #5016?

  1.  The cylindrical piece on the front of the cab near the top on the engineer's side.

  2.  The, what appears to be, two connected cylinder shaped objects under the right side running board above the rear set of drivers.

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Posted by 28882 on Saturday, July 28, 2012 10:06 PM

send pics, maybe i can help, mike

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Posted by Thomas 9011 on Sunday, July 29, 2012 6:26 PM

You know I have never really thought about it, but I can't ever remember seeing a photo of a Triplex connected to a train before. I have seen a handful of photos but they are builders photos. I have never seen any photos of it in action and I have a large collection of trains books and magazines.

I know the Triplex was a steam hog. It used so much steam that the boiler could never keep up with demand no matter how hot the fire was. Because of the great demand for steam it typically only operated at a very low speed and that could be the reason for lack of photos. Probably a pretty boring locomotive to see in operation. It was a prototype and from what I have read a mechanical nightmare to maintain. They were some of the shortest lived steam locomotives we ever had.

Most people would be surprised to learn that the tractive effort of a Triplex is a astronomical 176,256 pounds! It even has 66,000 more pounds of effort then the almighty Allegheny. Truly the most powerful steam locomotive ever created. As a collector I have never seen a triplex builders plate.  A ghost locomotive in the collecting and  historical world if there ever was one.

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Posted by Firelock76 on Sunday, July 29, 2012 7:18 PM

Ah, the Triplex.  You know, there were four of them built, three for the Erie, and one for the Virginian.  All were flops, the Erie's being scrapped by the late 20's, and the Virginian's rebuilt into a 2-8-8-2 and it's tender engine built into a 2-8-2.   You've probably never seen any pictures of them on a head end of a train as they were used in pusher service. 

I'm looking at a photo of one now, and I've no idea what that cylindrical thing is on the cab in front of the engineers cab.  The two cylindrical things on top of the first set of drivers look like air compressors. 

As far as conversion to electricity, and I'm assuming you mean going from a kerosene to electric headlight, I believe the FCC mandated the change just prior to the First World War.  Whether this only applied to road engines and pushers were exempt I don't know. I can't find a picture of a Triplex with an electric headlight here in the "archives."

Adding insult to injury, the Triplexes were too big for the Erie's own shops!  The Lehigh Valley had to do Erie's Triplex maintainance!

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Posted by Firelock76 on Sunday, July 29, 2012 8:32 PM

Hey, do you want to see some footage of a triplex in action?  Well, not really, but search You Tube Premiere O Gauge Erie Triplex and watch what comes up.  It's a close as we'll ever get!

Oh, and earlier I meant to say ICC, not FCC.  Sorry.

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Posted by CAZEPHYR on Sunday, July 29, 2012 9:35 PM

Yes, the Erie Triplex could start a train but ran out of steam over 10MPH according to stories about the locomotive.  It was used in slow pusher service for a time.  It was a failure big time and only used in pusher service.  Even that was limited by the small tender.  There is a quote in the Baldwin book about the Triplex.  " It used to be said by Erie men tht the coolest spot on a hot summer's day was sitting behind the backhead of the Matt H. Shay."   In other words, It did not generate steam well at all.

 The Virginian Triplex was a little better since it had a much larger boiler on it, but was converted to a 2-8-8-0 eliminating the drivers under the tender.


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Posted by CSSHEGEWISCH on Monday, July 30, 2012 10:25 AM

The triplexes were basically too much locomotive and not enough boiler.  George Henderson, who designed the triplexes, also had quadruplexes and quintuplexes on the drawing board.

The daily commute is part of everyday life but I get two rides a day out of it. Paul
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Posted by tpatrick on Saturday, August 04, 2012 6:44 PM

The real flaw in the Triplex design was not inadequate boiler, but inadequate draft. It just couldn't breathe. The middle pair of cylinders were high pressure. Exhaust from the right cylinder went forward to be reused in the low pressure pair and exhaust from the HP left went rearward. The rear cylinders exhausted out the stack behind the tender. Thus, only half of the engine's output exhausted through the smokebox to provide draft for the fire. And, having already been through two sets of cylinders, that exhaust was pretty much a spent force. Airflow through the grate was minimal at best.

The Triplexes were delivered in 1914 and scrapped in 1927. That is a short life but in their time they did a lot of useful work. Had they been able to route 100% of their exhaust through the smokebox they would have bee more capable, but you could question whether it would have made much difference. IMHO they were not failures, but by 1927 Erie was clearly looking to the new "Super Power" technology built into their new fleet of Berkshires.

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Posted by Deggesty on Monday, August 06, 2012 11:05 AM

I remember reading, back in the fifties that the exhaust from the rear engine went through the water tank, thus warming the water a little--getting some additional use from the steam. This, of course, was not as valuable as increasing the draft by routing the exhaust through the smokebox. Did anyone ever think of keeping the blower on all the time?


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Posted by 28882 on Tuesday, August 07, 2012 10:31 AM

Over the years   I've  watched all the comments about the Erie Triplex, most have been centerd around its shortcomings. I believe these were sucessful  locomotives doing the job they were purpose designed to do, drag - pusher work on the Erie RR, after the inital trials, improvments and acceptance by Erie they orderd 2 more, they must have been confident that these would be money savers. They did have short lives for locomotives of this era, overtaken by technological improvements. Baldwin locomotive works had a brilliant engineer, George Harrision assigned the awesome task of designing the first Triplex, his task was made somewhat easier by using components from there Mike. Because of the massive size of the firebox at that time he was one of the first to incorporate a mechanical stoker, it  could also be fired by hand if necessary thru two holes in the backhead,  he also incorporated the fairly new Baker valve gear in the design, plus design inovations which were patented. Yes only half the draft was available in the smoke box, but the other half was directed though a huge feed water heater almost the full length of tender so very hot water was pumped into the boiler, so most of the ( waste) energy not used for locomotion was used for making steam.   mike darbyshire 

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Posted by 28882 on Tuesday, August 07, 2012 10:48 AM

sorry about the name Harrision should read Henderson mike

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