Level Crossing Barrier design -- shear pins?

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Do British level crossing barrier arms have shear pins fitted for quick repair following impact with vehicles? Or is it a matter of fit a complete fresh gate, and bring the damaged one back to the depot for repair and then keep as a spare?
 
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Cowley

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Do British level crossing barrier arms have shear pins fitted for quick repair following impact with vehicles? Or is it a matter of fit a complete fresh gate, and bring the damaged one back to the depot for repair and then keep as a spare?

Actually to pin another question on to yours. Are the gates produced in a few set sizes?
 

pdeaves

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Do British level crossing barrier arms have shear pins fitted for quick repair following impact with vehicles? Or is it a matter of fit a complete fresh gate, and bring the damaged one back to the depot for repair and then keep as a spare?
There are sacrificial parts (whether pins or something else I know not). However, sometimes other damage occurs as well, requiring replacement anyway.
 

High Dyke

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Actually to pin another question on to yours. Are the gates produced in a few set sizes?
Not certain overall, but some locations have bespoke lengths for barriers. I've known local repair teams make on-site adjustments to barriers to make them fit.
 

swt_passenger

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Aren’t there also some locations that have had historical problems where a spare set of barriers are available on site, eg Cosham?
 

MadMac

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Aren’t there also some locations that have had historical problems where a spare set of barriers are available on site, eg Cosham?
I think there’s a spare set kept for Logans Road at Motherwell.

The OP seems to be thinking about the US-style fibreglass barriers. They “telescope“ inside one another, come in pre-made lengths and can be cut to size on site. They fit to an “adaptor” which fits onto the gate mechanism on a bayonet fitting which is in turn held by bronze “shear pins”. The idea is that if the barrier is hit, it’ll break the shear pins and it‘ll fall off: if you’re REALLY lucky, you can pick it up, fit it back on and replace the pins.
 

The exile

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Another question about level crossings - prompted by an observation at Sturry this morning, where the barriers started to come down with a fairly slow-moving elderly lady still on the crossing. Sturry has full barriers and as she was (correctly) walking facing the oncoming traffic, the first barrier she came to was not yet coming her hea down. When they were half-way down they stopped, leaving her confronted by a half closed barrier blocking her exit. Spotting what had happened but assuming the barriers had failed, I told her that the safest thing to do was to walk out into the middle of the (busy) road to get clear of the crossing (the other barrier wasn't going to come down suddenly on her head and the car drivers could see what was going on) - which she did, at which point the barriers continued their descent. I assume therefore that they were being monitored (either by obstruction detection or good old human eye), but if she had decided to wait, what would then have happened (and after how long?)
 

Gloster

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Another question about level crossings - prompted by an observation at Sturry this morning, where the barriers started to come down with a fairly slow-moving elderly lady still on the crossing. Sturry has full barriers and as she was (correctly) walking facing the oncoming traffic, the first barrier she came to was not yet coming her hea down. When they were half-way down they stopped, leaving her confronted by a half closed barrier blocking her exit. Spotting what had happened but assuming the barriers had failed, I told her that the safest thing to do was to walk out into the middle of the (busy) road to get clear of the crossing (the other barrier wasn't going to come down suddenly on her head and the car drivers could see what was going on) - which she did, at which point the barriers continued their descent. I assume therefore that they were being monitored (either by obstruction detection or good old human eye), but if she had decided to wait, what would then have happened (and after how long?)
I don’t know about modern protocols, but forty years ago the signalman would stop the barrier just far enough down to stop oncoming motor vehicles and then expect the pedestrian to take the opportunity to move out into the road, where traffic was stopped, in order to have sufficient headroom. If they didn’t have the sense to do that, then if it was locally controlled by a box the pedestrian would be verbally advised what to do. If it was remotely controlled and no car driver said anything to the pedestrian, then the only thing to do is lift the barriers and hope the pedestrian collects their wits and goes on their way. It was often possible to lift the barriers so that they were nearly vertical, but the lights were still flashing, so you could just drop the barriers back down afterwards, rather than going through the whole sequence again. But you had to watch for cars creeping forward.
 

High Dyke

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Another question about level crossings - prompted by an observation at Sturry this morning, where the barriers started to come down with a fairly slow-moving elderly lady still on the crossing. Sturry has full barriers and as she was (correctly) walking facing the oncoming traffic, the first barrier she came to was not yet coming her hea down. When they were half-way down they stopped, leaving her confronted by a half closed barrier blocking her exit. Spotting what had happened but assuming the barriers had failed, I told her that the safest thing to do was to walk out into the middle of the (busy) road to get clear of the crossing (the other barrier wasn't going to come down suddenly on her head and the car drivers could see what was going on) - which she did, at which point the barriers continued their descent. I assume therefore that they were being monitored (either by obstruction detection or good old human eye), but if she had decided to wait, what would then have happened (and after how long?)
Essentially the lowering sequence has been stopped by the Mk.1 eyeball observing the pedestrian. However, incidents of person trapped inside the barriers still happen. I was made of such an incident this week.

The MOP did the correct thing by exiting sensibly, I've seen incidents of those who panic and freeze, not knowing what to do.next (OK, they don't necessarily know a train won't turn up). The signal(wo)man won't clear the protecting signals in this instance.
 

Bald Rick

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Do British level crossing barrier arms have shear pins fitted for quick repair following impact with vehicles? Or is it a matter of fit a complete fresh gate, and bring the damaged one back to the depot for repair and then keep as a spare?

Yes they have shear bolts.

However depending on the nature of the damage, sometimes a new barrier is needed anyway.
 

Llanigraham

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Another question about level crossings - prompted by an observation at Sturry this morning, where the barriers started to come down with a fairly slow-moving elderly lady still on the crossing. Sturry has full barriers and as she was (correctly) walking facing the oncoming traffic, the first barrier she came to was not yet coming her hea down. When they were half-way down they stopped, leaving her confronted by a half closed barrier blocking her exit. Spotting what had happened but assuming the barriers had failed, I told her that the safest thing to do was to walk out into the middle of the (busy) road to get clear of the crossing (the other barrier wasn't going to come down suddenly on her head and the car drivers could see what was going on) - which she did, at which point the barriers continued their descent. I assume therefore that they were being monitored (either by obstruction detection or good old human eye), but if she had decided to wait, what would then have happened (and after how long?)

Firstly she quite obviously ignored the flashing lights and sounder signifying that the crossing had been activated.
Secondly the crossing is obviously directly monitored by a signalman who was able to see her and stop the barriers dropping That does not seem to happen with the obstruction detection system.
 

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