Ron Heggs Posted July 28, 2015 Share Posted July 28, 2015 I have noticed on photographs of the terminal rail arrangements on Manchester Central Station which closed in 1969, what appears to be a possible locking bar arrangement between the release road turnout and the terminal buffers The rail and bar in question is adjacent to left running rail This arrangement is common to all nine terminal platform roads Any help would be much appreciated Ron Link to post Share on other sites More sharing options...
RMweb Premium jamie92208 Posted July 28, 2015 RMweb Premium Share Posted July 28, 2015 It looks to be a facing point lock. This stops the points being changed when a vehicle is moving over them. The bar would be as long as the wheelbase of any vehicle that ran on the line. The wheel flange pressed the bar down and locked the point so that until the vehicle was clear the lever could not be pulled. These were normally provided for facing points at junctions. I believe that the levers for the locks were painted blue. Jamie Link to post Share on other sites More sharing options...
stadman Posted July 28, 2015 Share Posted July 28, 2015 Could it be to operate a light in the signal box in absence of track circuiting? Link to post Share on other sites More sharing options...
Ron Heggs Posted July 28, 2015 Author Share Posted July 28, 2015 These turnouts were operated locally by hand, and were not track circuited - so a light signalled in the signal box could be a possibility, showing that a possible loco movement was underway that was not yet under the signalman's control Link to post Share on other sites More sharing options...
Grovenor Posted July 28, 2015 Share Posted July 28, 2015 Those are "depression bars", they sit normally almost at rail height as in the photo, the strip in the fourfoot about 6 inches from the bar is a counterweight that holds the bar up. Any wheel running onto the bar depresses it via the wheel flanges (and raises the countersweight). There will be an electrical contact box linked to it which, as mentioned above will operate an indicator in the box to remind the signalman that he has something standing at the buffers. It may also prevent clearing of the main aspect into the platform so that the call on has to be used. These bars were common at platform ends where locos or vans may be left and rail conditions made track circuits unreliable. Regards Keith PS Jamie, Its clear in the photo that the points don't have any facing point lock. And locking the points by something standing on that bar would mean that the points could not be used for the only movement they are needed for! Link to post Share on other sites More sharing options...
Ron Heggs Posted July 28, 2015 Author Share Posted July 28, 2015 Those are "depression bars", they sit normally almost at rail height as in the photo, the strip in the fourfoot about 6 inches from the bar is a counterweight that holds the bar up. Any wheel running onto the bar depresses it via the wheel flanges (and raises the countersweight). There will be an electrical contact box linked to it which, as mentioned above will operate an indicator in the box to remind the signalman that he has something standing at the buffers. It may also prevent clearing of the main aspect into the platform so that the call on has to be used. These bars were common at platform ends where locos or vans may be left and rail conditions made track circuits unreliable. Regards Keith PS Jamie, Its clear in the photo that the points don't have any facing point lock. And locking the points by something standing on that bar would mean that the points could not be used for the only movement they are needed for! Thanks Keith. I suspected there would be a simple answer At least I can model it knowing what its purpose was, and even make some possible use of it during operations Cheers Ron Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted July 28, 2015 RMweb Gold Share Posted July 28, 2015 Definitely a depression bar - they were quite common in that position in 1930s and early postwar resignalling schemes on the LMS and LNER. Link to post Share on other sites More sharing options...
scotcent Posted July 28, 2015 Share Posted July 28, 2015 Glasgow Central had lots of these things, installed when the station was resignalled about 1900. They were at all the buffer stops, and also at the platform ends. The Rulebook contained an instruction that locomotives following a train out of the station must stand on the bar until the signal was returned to danger and then cleared again. They predated track circuits and were used as Grovenor states where TC's might be unreliable. They were still in use at Glasgow until resignalling in the 1960's, and I noticed one in the South Bay Platform at Perth very recently, though I don't know whether it's still functional Allan F Link to post Share on other sites More sharing options...
RMweb Premium newbryford Posted July 29, 2015 RMweb Premium Share Posted July 29, 2015 ISTR depression bars were in use at Preston in platforms 3a/4a (south bays), also at Blackburn in P3 - west bay, until recent years. I can't find my photos at the moment. Often used in locations where the railhead could be dirty and affect track circuit operation. (Bay platforms/terminal roads didn't have regular faster moving traffic to keep the railhead clean) In the photo in the OP, the end of the depression bar is just visible under the buffer stop beam. The more recent solution to replace the bar is a "zig-zag" pattern of weld along the railhead to offer some degree of abrasion to keep it clean to actuate track circuits. Certainly very noticeable/audible when a train runs in over it. Cheers, mick Link to post Share on other sites More sharing options...
woodenhead Posted July 29, 2015 Share Posted July 29, 2015 Thanks Keith. I suspected there would be a simple answer At least I can model it knowing what its purpose was, and even make some possible use of it during operations Cheers Ron 'make some possible use of it' - you don't mean, and given your attention to detail it wouldn't surprise me, you intend to use them for track circuiting? Link to post Share on other sites More sharing options...
Londontram Posted July 29, 2015 Share Posted July 29, 2015 I'm not 100% but I think this or something very like it is still on the ends of the track at Great Yarmouth Vauxhall station. I've got to pop out later so will try and get some photos Link to post Share on other sites More sharing options...
Grovenor Posted July 29, 2015 Share Posted July 29, 2015 I thought there was a drawing in one of my books but all I can find is this technical photo. It has a different style of contact box (with cover taken off and resting against the balance bar) than the ones I remember which were standard little rectangular contact boxes screwed to a sleeper with a short rod linkage to the bars. Note its called a fouling bar in the pic. A name that causes confusion with mechanical fouling bars worked from a lever in the box, we called them depression bars in the 1960s. This illistration is from 1925. Regards Keith Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted July 29, 2015 RMweb Gold Share Posted July 29, 2015 I thought there was a drawing in one of my books but all I can find is this technical photo. It has a different style of contact box (with cover taken off and resting against the balance bar) than the ones I remember which were standard little rectangular contact boxes screwed to a sleeper with a short rod linkage to the bars. Note its called a fouling bar in the pic. A name that causes confusion with mechanical fouling bars worked from a lever in the box, we called them depression bars in the 1960s. This illistration is from 1925. depression bar.jpg Regards Keith The nomenclature thing can be a bit of a minefield alas. A depression bar is exactly that but they can be used as fouling bars (even the GWR used them in that role) although their most common use seems to have been for vehicle detection purposes in dead ends where poor rail conditions made track circuits unreliable and in that use they were, in some schemes) supplemented by 'Vehicle On Line' switches which could cover a longer length of track than a depression bar. They seem not to have been used as facing point locking bars but it is possible that they were used in that way in early (pre1914 or so) power signalling schemes as the reliability of early track circuits seemed to have been rather variable. Link to post Share on other sites More sharing options...
SM42 Posted July 29, 2015 Share Posted July 29, 2015 Here is one at the stops at Lowestoft in May this year Andy Link to post Share on other sites More sharing options...
Grovenor Posted July 30, 2015 Share Posted July 30, 2015 Complete with rectangular contact box I referred to above. Thanks Keith Link to post Share on other sites More sharing options...
Judge Dread Posted September 7, 2015 Share Posted September 7, 2015 This type of "fouling bar" at platform ends, was replaced in later years by applying a zig-zag strip of electric weld to the rail surface which would not rust and thereby by give contact at any time. For the life of me I cannot remember what this material was but I suspect it would have been stainless steel. Link to post Share on other sites More sharing options...
LNERGE Posted September 7, 2015 Share Posted September 7, 2015 Complete with rectangular contact box I referred to above. Thanks Keith It's a Tyer and Co two way circuit controller. You will find them doing this job, up signals, next to points to control variable track circuit limits and under signalboxes. Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted September 7, 2015 RMweb Gold Share Posted September 7, 2015 This type of "fouling bar" at platform ends, was replaced in later years by applying a zig-zag strip of electric weld to the rail surface which would not rust and thereby by give contact at any time. For the life of me I cannot remember what this material was but I suspect it would have been stainless steel. I understand it to be stainless steel but I believe in some later installations something cheaper was use - but I'm not sure what it was although the way it 'squashed' in use made me wonder if it was the stuff used for track circuit bonding? Link to post Share on other sites More sharing options...
LNERGE Posted September 7, 2015 Share Posted September 7, 2015 I have had to do this on a level crossing i look after. The original welding was installed by BR and was super hard stainless but this has 'rolled out' in a few places. The stuff i've had done was in a malleable stainless. It is slightly better but the traffic over said crossing is now frequent enough to keep the rails clean and we are looking to change the rails etc. Link to post Share on other sites More sharing options...
sigtech Posted September 7, 2015 Share Posted September 7, 2015 I think this wavy stainless steel strip fitted to the railhead is called an 'eutectic strip', can remember seeing them at Kings Cross in the 70's at the bufferstops end of the platforms - where the diesel locos stood and the track was black and covered in oil. Depression/fouling bars were also provided in some track layouts on running lines where it was difficult for the signalman to judge clearance/ when the back of a train was clear of the fouling point, to prevent him allowing a conflicting move to occur. Regards SIGTECH (Steve) Link to post Share on other sites More sharing options...
LNERGE Posted September 7, 2015 Share Posted September 7, 2015 I think this wavy stainless steel strip fitted to the railhead is called an 'eutectic strip', can remember seeing them at Kings Cross in the 70's at the bufferstops end of the platforms - where the diesel locos stood and the track was black and covered in oil. Depression/fouling bars were also provided in some track layouts on running lines where it was difficult for the signalman to judge clearance/ when the back of a train was clear of the fouling point, to prevent him allowing a conflicting move to occur. Regards SIGTECH (Steve) I've been trying to remember what it was called all evening. How about this for possibly the highest number of electric depression bars indicated in one box?.. Link to post Share on other sites More sharing options...
RMweb Premium Siberian Snooper Posted September 7, 2015 RMweb Premium Share Posted September 7, 2015 It may be Stellite , this is a hard wearing Cobalt alloy which is corrosion resistant. I believe that it has also been used to build up common crossing noses. We used it to build up worn boiler hand hole door seatings. Link to post Share on other sites More sharing options...
LNERGE Posted September 7, 2015 Share Posted September 7, 2015 I've been trying to remember what it was called all evening. How about this for possibly the highest number of electric depression bars indicated in one box?.. Whitemoor Junction (1960's)lr.jpg Brainwave just occurred but after a quick look and count up WJ and KX both have 13 bars. https://www.flickr.com/photos/pwayowen/15990737357/ Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted September 7, 2015 RMweb Gold Share Posted September 7, 2015 Brainwave just occurred but after a quick look and count up WJ and KX both have 13 bars. https://www.flickr.com/photos/pwayowen/15990737357/ I wonder how many there were at York as I can remember them being at the blocks end of some of the terminal platforms (which also had VOL switches!) Link to post Share on other sites More sharing options...
Junctionmad Posted September 7, 2015 Share Posted September 7, 2015 My understanding is that fouling bars are a generic term, the OPs picture is a clearance bar used to indicate to the signalman, that a loco is standing clear of the point. Fouling bars used to lock FPLs , I believe are known as facing point locking bars. , certainly in signal engineering docs I've read Link to post Share on other sites More sharing options...
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