EMR broke down at Luton: Air suspension failure?

[Aictos]

Hearing reports that the air suspension on 1B36 11:12 Nottingham to London has failed and has now terminated.

What could cause the air suspension to fail?

 

[Llama]

Burst air bag, air leak on pipework of any part of the suspension system, valves failing, could be many different things.

 

[Aictos]

Burst air bag, air leak on pipework of any part of the suspension system, valves failing, could be many different things.

Not to mention the train will be rattling like no tomorrow?

 

[Raul_Duke]

20mph out of service in a meridian with failed air suspension as well iirc. Ouch.

 

[Llama]

Not really, there are secondary springs within most airbags, obviously I don't know what traction type it was. Deflated air suspension usually gives quite a lively ride and is often accompanied by a reduction in maximum permissible speed (say, on Sprinters max 45mph) especially if the affected vehicle is carrying passengers. If the affected vehicle is locked out of public use the max speed may be higher depending on traction. The actual instructions vary from TOC to TOC and for different traction. Most Sprinters etc are 45mph max with deflated suspension if in passenger service, up to permissible speed if affected vehicle locked out of use (Northern have an instruction for 156s which are still max 45 even if OOU, due to slightly different emergency springs apparently).

There are often a couple of other considerations for deflated air suspension at least on Sprinter type stock - brake cylinder pressures are high due to the load weighing system on the unit thinking it is fully loaded, and when coupling to other units.

 

[Aictos]

20mph out of service in a meridian with failed air suspension as well iirc. Ouch.

I thought it was 40mph? Then again I’m not a driver nor do I use them/passed out on them.

 

[Raul_Duke]

I thought it was 40mph? Then again I’m not a driver nor do I use them/passed out on them.

Just checked my traction manual and you’re right.

 

[Aictos]

Just checked my traction manual and you’re right.

Wow that’s a first! Lol!

 

[tsr]

Went at 40mph to Cricklewood. Fault was first identified north of Bedford by the TM and then it sat down for a bit at Luton. Caused a bit of congestion but nothing really awful.

 

[hooverboy]

Hearing reports that the air suspension on 1B36 11:12 Nottingham to London has failed and has now terminated.

What could cause the air suspension to fail?

compressor fault?
that would surely affect brakes as well though?

 

[hooverboy]

Not really, there are secondary springs within most airbags, obviously I don't know what traction type it was. Deflated air suspension usually gives quite a lively ride and is often accompanied by a reduction in maximum permissible speed (say, on Sprinters max 45mph) especially if the affected vehicle is carrying passengers. If the affected vehicle is locked out of public use the max speed may be higher depending on traction. The actual instructions vary from TOC to TOC and for different traction. Most Sprinters etc are 45mph max with deflated suspension if in passenger service, up to permissible speed if affected vehicle locked out of use (Northern have an instruction for 156s which are still max 45 even if OOU, due to slightly different emergency springs apparently).

There are often a couple of other considerations for deflated air suspension at least on Sprinter type stock - brake cylinder pressures are high due to the load weighing system on the unit thinking it is fully loaded, and when coupling to other units.

that does seem curious.
why the variance between TOC?

I would understand the remedial measures being traction specific.
Evacuation procedures may vary by TOC(ie on 158/159 with third rail present, but I'd expect someone passed on the traction to know it,irrespective of if they were running on that type of route or not)

 

[CC 72100]

compressor fault?
that would surely affect brakes as well though?

Could be an air leak within the air suspension system. Isolating the air suspension from the Main Reservoir pipe would prevent further air loss on the vehicle but the downside would be insufficient air to operate the (already damaged) air suspension.

 

[CC 72100]

that does seem curious.
why the variance between TOC?

I would understand the remedial measures being traction specific.

Different TOCs have done different 'things' to their units in the +20 years since privatisation. Plenty of scope for different modifications and renewals that other fleets of the same class in a different part of the country may not have received.

Or just different because somebody different has decided it...!

 

[hooverboy]

Different TOCs have done different 'things' to their units in the +20 years since privatisation. Plenty of scope for different modifications and renewals that other fleets of the same class in a different part of the country may not have received.

Or just different because somebody different has decided it...!

It would appear to be quite beneficial to have a few less of these "modifications".It would make training people to operate them far easier.

 

[308165]

It may not be relevant here but there are also gauging restrictions on units with deflated air suspension. Either total bans from certain platforms or much reduced speed.