I had not earlier realised the railway standards for IWLR wheels, in which case the sensible thing to do with its special work would be to reduce the flangeway width to match the George St line, and wheel profile as well. This may need to be done in 2 steps.
Regards,
> On 17 Sep 2017, at 9:31 pm, 'Dudley'transitconsult@... [TramsDownUnder] TramsDownUnder@...> wrote:
>
> Railway style wheels have much wider tyres than street tramway tyres. This enables them
> to bridge the wide gaps at frogs. See
> https://en.wikipedia.org/wiki/Comparison_of_train_and_tram_tracks for a diagram showing
> the relative widths of tyres - unfortunately without dimensions.
>
> Yarra trams specification for the width of the groove on normal straight or curved track
> is 30 mm, but this is reduced to 26 mm opposite frogs at sets of points. The 30 mm on the
> straight allows for lateral play, but this is reduced to the minimum where this lateral
> play cannot be allowed. The nominal gauge of 1435 mm is widened at points to 1438 mm -
> see diagrams YTS 1103 and 1208.
>
> In the UK, apart from Crich, flange thicknesses vary from 22.0 to 29.0mm, with 6 systems
> using widths between 22.0 and 23.2mm, with Docklands at 27.5 and Tyne and Wear at 29.0mm.
> See:
> http://webarchive.nationalarchives.gov.uk/20170206160525/http://orr.gov.uk/__data/assets/p
> df_file/0004/4387/sres-RTU-rep_90_3A_iss1.pdf - an invaluable document for comparison of
> wheel profiles and rail profiles in the UK.
>
> https://books.google.com.au/books?id=04z0Lw1qKiIC&pg=SA2-PA44&lpg=SA2-PA44&dq=AAR++wheel+d
> esign&source=bl&ots=rP8lYTZpBX&sig=GwEb8e5zH6h47e2t9dKYhoTpVj8&hl=en&sa=X&ved=0ahUKEwi-wJu
> mhqzWAhULvbwKHTPICMIQ6AEISzAL#v=onepage&q=AAR%20%20wheel%20design&f=false
>
> According to the above book, at 2.6.6, the AAR standard wheel thickness for Light rail
> vehicles is, if I read it correctly, 145mm. This is 10 to 20mm wider than most of the UK
> wheel profiles, which are down to 115mm for some trams (excluding the Crich trams which
> have even narrower wheels). Para 2.6.6 gives the reasons for having a wider tread when
> not using flange running.
>
> I have no idea what dimensions the IWLR and the CSELR use for their flangeways, flange
> widths and wheel treads, but I cannot help thinking that given the use of the railway
> standard points on the IWLR - which are no longer needed as the connexion with the Goods
> Lines has been severed, never likely to be reopened - it would be desirable to convert all
> the railway style points to flange running, so there is no problem with the wheels falling
> into the gap at frogs. At the same time, it would be desirable to reduce flangeway widths
> at frogs to 26mm as peer YT standard (fat chance I hear you say, copy Melbourne? No
> way!).
>
> -----Original Message-----
> From:TramsDownUnder@... [mailto:TramsDownUnder@yahoogroups.com]
> Sent: Sunday, 17 September 2017 4:06 PM
> To:TramsDownUnder@...
> Subject: Re: [TramsDownUnder] Re: Tram-train: where did we go wrong?
>
> On 17/09/17 00:37, Mal Rowemal.rowe@... [TramsDownUnder] wrote:
>
> >> The attached is part of a drawing with an original date of 1995 and it makes reference
> to an even older ABB drawing. And presumably Karlsruhe had to solve this issue 'way back'.
> >>
> >> The key item is the stepped wheel back.
> >>
> >
> > Is this only a major issue when you keep railway style points?
> >
>
> Yes.
> I believe back when the Sydney Light Rail wass being planned, the mills along the line
> were still operating. So the system was designed to allow wheat trains to access the mill
> at Jones Street near the fish market at what is now the Wentworth Park tram stop. The mill
> closed before the light rail project even started and was an abandoned factory by the time
> the trams started running.
>
> Despite the mill ceasing to operate (and others along the goods line following over the
> next few years) the railway points were kept in the design, even on the Dulwich Hill
> 'extension' where they quite definitely cut the connection to the heavy rail network.
>
> Shortly after the line opened, the residents next to Wentworth Park made many complaints
> about the noise from the trams, and thus 'fillers' were put in the frogs so the wheels
> would flange run through the points instead of banging through them. Thus the points can
> no longer take a rail vehicle anyway.
> At the same time one of the Variotrams (I think 2102, but would have to look it up) was
> fitted with a flange lubrication system. Just one tram fitted with this cut down the
> flange squeal for the entire fleet.
>
> It's not clear what modifications will be needed to allow the street wheel profile Citadis
> to access the Lilyfield maintenance centre - there are several sets of railway geometry
> points between Haymarket and Lilyfield.
>
> ------------------------------------
> Posted by: Matthew Geier matthew@...>
> ------------------------------------
>
> ------------------------------------
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