BR Standard class 6 No. 72010 'Hengist' and Clan Discussion Thread

Correct of course o mighty tank I don't actually know whether the lot 242 drawings feature plain or fluted rods , but as far as I know Hengist will have the plain w/r style coupling rods and this has been given the nod by the VAB.
Indeed we have been warned and this point, especially that the Clan axles are all 9 inch, whereas the Brit driver axles were 9 /10/ 9 inch respectively has been pointed out.
An increase in starting Tractive effort isn't always a good thing for a Pacific. but having a bit more grunt at 40% cut of is something the engine might benefit from.

Bit of a conversation on the farcebook page about whether Hengist should go plain bearings... if that gives a bigger bearing surface then maybe theres something in it, but the reason given
'Locos with roller bearings- problem is that the bearings leave impressions on the journals if they are stood motionless for long periods'
is a new one on me.... any one got an angle on that ?

 

It is true - known as brinelling (might have the spelling wrong). When I was lead engineer on a project to create a new measurement train for the Underground one of my main concerns was trying to get the wheels rotated every four weeks as per OEM guidelines.

I suspect there is some leeway and it does depend on the load the bearing and particularly each rolling element places on the race plus the hardness of those components.

The bearing manufacturer (Timken?) should be able to advise.

Regards,

Dan

 

David Wardale wrote about bearing wear on stored locomotives in "The Red Devil", he also added the potential for damage to bearings on stored locomotives in sidings via vibration from passing trains. The same issue of bearing damage is the same with other motionless vehicles such as cars, etc.

Cheers,

Alan

 

When I worked in a lab, we had a very expensive rotary high-vacuum pump that saw slightly intermittent use, and it was a weekly duty to turn it over regardless of whether it had been used during the week to avoid damage to the bearings from sitting in one position for an extended time.

With regard roller versus plain bearings: an ex-BR driver of my acquaintance who back in the day worked on a variety of locomotives with both types was of the view that roller-bearing locos rode "harder" and over the course of a day left your legs more tired relative to working on an otherwise similar type with plain bearings.

Tom

 

Huh, these are really interesting points. I never knew either. Way off topic, but I left my car for a month last year after two new front wheel bearings. When I came back and drove it again the passenger one was beaked. It was really odd and now I have a possible cause.

 

There's a difference between brinelling and false brinelling. Both can be an issue with classic or vintage motorcycles, which I know about, and I suspect rail vehicles, about which I know less.

 

Well, I've learned something new. Very interesting.

 

Has this come to light in view of the two Brits which have had various axle related problems recently ? am I right in thinking that those two, 71000 and 60163 are the only roller bearing mainliners out there ?
and of course Tornado is never still for long enough for this to be a problem...

 

Only 70000 has had axle related problems. Stanier Class 5 44767 is fitted with roller bearings, although it is a kit of parts at the present time.

 

And 73096 (although no longer on the mainline)


Keith

 

BR standard tenders, roller bearings? I was aware of the problems that can occur with roller bearings having done the bearing course at BR Tyseley .

 

Didn't Tornado have a couple of canon-boxes replaced a few years ago?

Cheers,

Alan

 

Does the same apply to Roller bearing wagon stock?
Just thinking about our fleet of 5 Seacow / Sealion ballast hoppers that were sat for years in the scrap yard at Stockton.

 

Brinelling of stationary roller bearings as a phenomenon is usually associated with vibration from external sources or static overload. Although the roller and race are essentially in point contact there has to be some deformation otherwise the stress would be infinite. Highly loaded bearings are more likely to suffer than lightly loaded ones unless vibration is the key element. Whether it is a rolling contact or plain bearing, it is a good idea to rotate it as intervals to maintain the bearing surfaces. No matter how good the seals are, moisture will almost certainly eventually get into the bearing and displace the protective lubricant film, causing corrosion. Many years ago, I was told that BR had an instruction that stored steam locos had to be moved at least one wheel revolution every three months.
To answer Ploughmans question, unless your wagons were stored fully loaded or subject to vibration, I would think Brinelling is unlikely. Corrosion would be your biggest worry but were they stored in a truly static condition or moved occasionally?.

 

I know that the tender currently being restored for use behind 2MT 78019 at the GCR (The tender 78019 had previously ran with in preservation is now behind 78018) doesn't actually have roller bearings, but is being restored with the necessary aesthetic additions to make it appear, without actually looking in detail at the bearings, as though it has roller bearings. I think that's because it's actually got a tender originally built for an LMS 2MT, which didn't have roller bearings, although I could be wrong there. I wonder if there are any locos which, though they would have had roller bearings in BR days, have through one reason or another come to not have those bearings but have been restored to make it look like they do...?

 

Isn't this the case with the tender from 73096, which started life as a Stanier 3,500 gallon one?

 

The tender frames on 73096's tender are ex 45593 Kolhapur. The tender frames at the GCR that came with 78018 are ex Ivatt 2-6-0 46428.
Interestingly, 73096 is fitted with Skefco roller bearings, but its original tender would have been fitted with Timken roller bearings.

 

Some bedtime reading....
http://www.skf.com/binary/86-62751/RTB-1-06-Bearing-investigation.pdf

 

Interesting that the term Brinelling does not get a mention (although false Brinelling does.) but is simply categorised as plastic deformation.

 

All this very interesting. As we ,NTSRA, will be rebuilding 401 (Victor?) in 2018 I wonder how our roller bearings will manage? An intermittent use, weekends mainly, lightly loaded, 7 miles return trip scenario, somehow I don't think it will be too much of a problem + the fact that it is hardly likely we can get the finance to change the axle bearings to plain now.

I do enjoy the snippets of advice and information that are shared on this thread. All willingly given for the good of the project, it's wonderful to have your support folks.

Anyway, who thinks 'Hengist' is going to be stood around long enough to have this problem!
Far to useful an engine, dear me, fancy someone thinking that!