P2 Locomotive Company and related matters

Yes, as you say 'Cooper' Split roller bearings were specifically designed for this type of operation, I believe S.K.F. have also entered the market with a similar product and, possibly 'Timken' U.S.

 

I think this image from Tornado's construction might help.... although it shows the eccentric for the drive to the middle valve gear is also shows the plain bearing big end and the Timken roller bearings sandwiched in place between the wheels and the crank webs.



Foxy

 

I like that picture very much.Do You have more?

 

I have asked this question to the P2 engineers in the knowledge that such a thing was trialled on some royal scots and was one re-design away from being a complete success. But given that the original A1 s or specifically Tornado have never had a problem with this component there wasn't a problem requiring that solution...

 

On this subject of inside cylinder roller bearing big ends, the 1957 built German Class 10 locomotive 10 001 was built new with one, but it only lasted a year or so in service before the wheelset and axle were replaced by a regular plain bearing type. I believe (open to correction) that the roller bearing wheel set still exists and is at the Deutsche Damplok Museum at Neuenmarkt Wirsberg.

 

This locomotive:
http://nbjvm.se/sv/anglok/ånglok-sj-littera-e2-nr-1155
(click at the tumb nail)
actually has inside roller bearing big ends, and two of them as it is inside connected.
It is preserved at the Norbottens Järnvägsmuseum in Luleå in northern Sweden.
(The museum that had a big fire a year ago.)
And here is a close up of one of the big ends:
(Photograph Morrgan Claesson, Gothenburg.)

 

The picture with the inside conrod is interesting.
To me it looks like the crankshaft is assembled with the SKF oil pressure method that was unsuccesfully tried on the german baureihe 10.
Some of these locomotives were stored very far from manned sheds and were supposed to be working with very short notice in case of war.What did the Swedes know that the Germans did not ?

 

It might not be a question of knowledge as much as capability. Ball bearings, esp very high quality ball bearings were a Swedish speciality about the time of WW2. But you're getting into areas I know very little about.
Split ball bearings strike me as a technology that may be extremely tricky to get right in the particularly demanding application of a locomotive big end, but now getting into an area I know even less about. But I find it interesting I have never seen them used in the motorcycle engineering I am not unfamiliar with. All i've seen has been split plain bearings and one piece cranks, or else ball bearings and built up cranks.

 

Exactly. Getting continuous ball bearings right proved difficult and I imagine the problems would be magnified several times with the split variety - along with the cost.
Eric Langridge had a bit to say about the Scots' bearings in Vol 2 of 'Under 10 CMEs', with additions by Allan C Baker. Worth reading.

 

Andalfi 1 posted a pointer here (1381 - top of this page as it happens).

Cooper Bearings now part of the SKF group. Split roller bearings were invented in 1907 by Thomas Cooper whose company was based in Kings Lynn. It remains there to this day in spite of the company no longer being in family ownership.

Have a look at the company website in order to get some idea of the areas of application for these products.

In spite of the successful use and application of roller bearings throughout the railway world back in the good old U.K. they were largely seen as an unnecessary expense. Interestingly enough some well placed individuals could see no advantage in the application of the Kylchap exhaust system.

 

Changing tack slightly (but staying between the frames) progress has been made on fitting the sandboxes, requiring completely new design in the case of the rear ones....
https://www.p2steam.com/2017/06/20/sandbox-news/

Foxy

 

Beautifully placed, if I may say so...

 

Just looking at this again, top LHS, do the crank pins get welded in from the back once they are pressed in? Is this an NR requirement?

 

No, they aren't.

 

That looks like it is the head of the retaining bolt for the cap on the crank pin.

 

Looking at this picture, it appears that the hornguides and frame stretchers are bolted and not riveted. They don't give the impression of being temporary so I am assuming that this approach has been adopted throughout. Is this assumption correct?

 

From pictures of 2001 and the CAD model of 2007, it appears to have an LNER-standard square on the crank pin for the camshaft drive. I'd suggest the inside end of the crank pin has a couple of flats machined on to key it into a matching slot at the base of the bore in the wheel (so the crankpin hole isn't full diameter all the way through).

Fitted bolts for the horns and stretchers was common LNER practice wasn't it? I know Riley's ended up doing a lot of hot riveting on Scotsman, but my understanding was that was to avoid having to ream out worn holes still further.

I must admit, looking more closely I am wondering if those nuts are Nylocs, which I doubt the LNER was using.

 

Although I've never come across bolted frame stretchers, I've no idea about LNER practice in this respect . It just seemed unusual to me. I agree that the nuts appear to be Nyloc or similar, which is one reason why I assumed it was a final fix.

 

Have a look at the overhaul taking place on Sir Nigel Gresley. Nuts and fitted bolts, scores of them. 8126 is correct when it comes to Flying Scotsman and rivets being used as a solution to a wear issue. The P2 uses Philidas fasteners, have a look at the company website then glance back at the P2 images. The LNER used fitted bolts. W. O. Bentley trained on the railways, the GNR if I recall correctly, and had strong views on how best to assemble the chassis of his cars.

 

You are getting confused. The photo is of 60163's leading axle.