In message <scs30s$vir$1@dont-email.me>, at 14:53:32 on Fri, 16 Jul
2021, martin.coffee@round-midnight.org.uk remarked:
>On 16/07/2021 14:19, Roland Perry wrote:
>> In message <scrcn1$272$1@dont-email.me>, at 07:32:49 on Fri, 16 Jul
>>2021, Tweed <usenet.tweed@gmail.com> remarked:
>>> Roland Perry <roland@perry.co.uk> wrote:
>>>> In message <scqb63$9ks$1@dont-email.me>, at 22:00:35 on Thu, 15 Jul
>>>> 2021, Anna Noyd-Dryver <anna@noyd-dryver.com> remarked:
>>>>
>>>>>>>>>> The yaw damper fatigue cracking is still being investigated,
>>>>>>>>>>with strain
>>>>>>>>>> gauges fitted to two units, one GWR and one LNER.
>>>>
>>>>>>>>> I've seen a couple of ECS Paddington to Penzance and back IET round
>>>>>>>>> trips and wonder if that is this investigation?
>>>>>>>>
>>>>>>>> I don't know, but would have thought that it would be better
>>>>>>>>for the tests
>>>>>>>> to be performed on units in normal customer service, not doing
>>>>>>>>anything out
>>>>>>>> of the ordinary. After all, these trains had lots of testing
>>>>>>>>before being
>>>>>>>> introduced into service, which didn't find the fault which
>>>>>>>>showed up in
>>>>>>>> normal customer service.
>>>>>>>
>>>>>>> The strain gauge electrical connections have to go through
>>>>>>>partly-opened
>>>>>>> doors, I think, so the unit fitted with the equipment can't
>>>>>>>operate in
>>>>>>> service.
>>>>>>
>>>>>> Ah, I didn't know that. I assumed it could all be fitted underfloor.
>>>>>
>>>>> From the picture I saw, the sensors are fitted around the lifting
>>>>> bracket/yaw damper area, and the cables fed to inside the train.
>>>>
>>>> Meanwhile, the rest of the world has discovered Bluetooth.
>>>
>>> Strain gauges need calibrated front end electronics. That exists as
>>>off the
>>> shelf units and that is presumably what is being used. However said units
>>> are designed to go in benign environments.
>> No-one makes any strain-gauge equipment capable of operating in
>>other than a molly-coddled indoor environment? Doesn't pass my sniff
>>test.
>>
>I've used strain guages on the most extreme of military equipment where
>an IET is nothing in comparison. You can shove the gauges themselves
>pretty well any environment however the recording equipment is more
>sensitive and will have to be calibrated in for this trial.

That's inside the train.

--
Roland Perry

<martin.coffee@round-midnight.org.uk> wrote:
> On 16/07/2021 14:19, Roland Perry wrote:
>> In message <scrcn1$272$1@dont-email.me>, at 07:32:49 on Fri, 16 Jul
>> 2021, Tweed <usenet.tweed@gmail.com> remarked:
>>> Roland Perry <roland@perry.co.uk> wrote:
>>>> In message <scqb63$9ks$1@dont-email.me>, at 22:00:35 on Thu, 15 Jul
>>>> 2021, Anna Noyd-Dryver <anna@noyd-dryver.com> remarked:
>>>>
>>>>>>>>>> The yaw damper fatigue cracking is still being investigated,
>>>>>>>>>> with strain
>>>>>>>>>> gauges fitted to two units, one GWR and one LNER.
>>>>
>>>>>>>>> I've seen a couple of ECS Paddington to Penzance and back IET round
>>>>>>>>> trips and wonder if that is this investigation?
>>>>>>>>
>>>>>>>> I don't know, but would have thought that it would be better for
>>>>>>>> the tests
>>>>>>>> to be performed on units in normal customer service, not doing
>>>>>>>> anything out
>>>>>>>> of the ordinary. After all, these trains had lots of testing
>>>>>>>> before being
>>>>>>>> introduced into service, which didn't find the fault which showed
>>>>>>>> up in
>>>>>>>> normal customer service.
>>>>>>>
>>>>>>> The strain gauge electrical connections have to go through
>>>>>>> partly-opened
>>>>>>> doors, I think, so the unit fitted with the equipment can't
>>>>>>> operate in
>>>>>>> service.
>>>>>>
>>>>>> Ah, I didn't know that. I assumed it could all be fitted underfloor.
>>>>>
>>>>> From the picture I saw, the sensors are fitted around the lifting
>>>>> bracket/yaw damper area, and the cables fed to inside the train.
>>>>
>>>> Meanwhile, the rest of the world has discovered Bluetooth.
>>>
>>> Strain gauges need calibrated front end electronics. That exists as
>>> off the
>>> shelf units and that is presumably what is being used. However said units
>>> are designed to go in benign environments.
>>
>> No-one makes any strain-gauge equipment capable of operating in other
>> than a molly-coddled indoor environment? Doesn't pass my sniff test.
>>
> I've used strain guages on the most extreme of military equipment where
> an IET is nothing in comparison. You can shove the gauges themselves
> pretty well any environment however the recording equipment is more
> sensitive and will have to be calibrated in for this trial.
>
> I would not use Bluetooth for a number of reasons. There will almost
> certainly be a random loss of data, it might be small but something
> significant might be lost. The recording equipment has to be calibrated
> and the signals concerned might be minute so I would want that equipment
> mounted within the train. I would not want calibrated Bluetooth
> equipment mounted on the outside of the train, some of those sensors
> will be mounted on the bogies so the vibration will be quite high which
> is not good for calibrated electronics and an unnecessary risk to the
> trials. I also suspect they're not just instrumented one yaw lifting
> bracket/yaw damper area but at least several along the train so you're
> be operating quite a few Bluetooth interfaces which doesn't always go well.

Yes, a 9-car IET has three types of yaw damper arm, so at least three cars
would need instrumenting. But it might be wiser to instrument at least two
cars of each type. And I'd have thought both bogies in each carriage should
be covered.

The good news is that the equipment can all be body-mounted, with nothing
on the bogies. The cracks are all on the body supports.

>
> Speed is of the essence in this so why go to unnecessary complexity
> which the added risk of failure when the simple and quickest solution is
> possible and will give the necessary data.

Yes, definitely.

>
> I suspect that permanent monitoring equipment will be fitted to a few
> units in the medium term and I'm sure that will be a basic wired system
> as well.
>

Yes, that would be a good idea.

Roland Perry <roland@perry.co.uk> wrote:
> In message <scs23m$krh$1@dont-email.me>, at 13:37:58 on Fri, 16 Jul
> 2021, Tweed <usenet.tweed@gmail.com> remarked:
>> Roland Perry <roland@perry.co.uk> wrote:
>>> In message <scrcn1$272$1@dont-email.me>, at 07:32:49 on Fri, 16 Jul
>>> 2021, Tweed <usenet.tweed@gmail.com> remarked:
>>>> Roland Perry <roland@perry.co.uk> wrote:
>>>>> In message <scqb63$9ks$1@dont-email.me>, at 22:00:35 on Thu, 15 Jul
>>>>> 2021, Anna Noyd-Dryver <anna@noyd-dryver.com> remarked:
>>>>>
>>>>>>>>>>> The yaw damper fatigue cracking is still being investigated,
>>>>>>>>>>> with strain
>>>>>>>>>>> gauges fitted to two units, one GWR and one LNER.
>>>>>
>>>>>>>>>> I've seen a couple of ECS Paddington to Penzance and back IET round
>>>>>>>>>> trips and wonder if that is this investigation?
>>>>>>>>>
>>>>>>>>> I don't know, but would have thought that it would be better for
>>>>>>>>> the tests
>>>>>>>>> to be performed on units in normal customer service, not doing
>>>>>>>>> anything out
>>>>>>>>> of the ordinary. After all, these trains had lots of testing
>>>>>>>>> before being
>>>>>>>>> introduced into service, which didn't find the fault which showed up in
>>>>>>>>> normal customer service.
>>>>>>>>
>>>>>>>> The strain gauge electrical connections have to go through partly-opened
>>>>>>>> doors, I think, so the unit fitted with the equipment can't operate in
>>>>>>>> service.
>>>>>>>
>>>>>>> Ah, I didn't know that. I assumed it could all be fitted underfloor.
>>>>>>
>>>>>> From the picture I saw, the sensors are fitted around the lifting
>>>>>> bracket/yaw damper area, and the cables fed to inside the train.
>>>>>
>>>>> Meanwhile, the rest of the world has discovered Bluetooth.
>>>>
>>>> Strain gauges need calibrated front end electronics. That exists as off the
>>>> shelf units and that is presumably what is being used. However said units
>>>> are designed to go in benign environments.
>>>
>>> No-one makes any strain-gauge equipment capable of operating in other
>>> than a molly-coddled indoor environment? Doesn't pass my sniff test.
>>>
>>
>> But you’ve neglected all the rest of it. You need power, a housing, method
>> of mounting, a detailed safety analysis that all of this you’ve slung under
>> the train isn’t going to come off and damage something else. You’ve also
>> now got something that’s hard to access and thus hard to fix if it goes
>> wrong. All this to promote your pet Bluetooth proposition. If this were to
>> be something that you needed in service for many years to come you’d
>> perhaps put the effort in. But this is an experimental setup to get some
>> data to hopefully fix a problem quickly. You’ve yet to explain what major
>> benefits your Bluetooth solution brings. All sorts of things are available
>> for hostile conditions, but it takes time and money, sometimes a lot of
>> money, to tailor a solution.
>
> Or just buy it in:
>
> <https://appmeas.co.uk/products/instrumentation/bluetooth-strain-gauge-
> transmitter-b24-ssb/>

As far as I can tell from its rather poor spec sheet, it’s single channel
with a very low sample rate. You’d need loads of them and it’s not obvious
what maximum frequency they are interested in. I suspect more than 1 Hz.
The unit has no vibration spec for the electronics. You’d still have to
make a safety case for mounting them outside of the passenger accommodation
and probably much more in that respect if you wanted to run the train in
passenger carrying service. It’s not obvious what problem you are trying to
solve with Bluetooth. The unit you propose is probably designed to go on
the outside of a building to measure slowly propagating cracks, eg the
monitoring they were doing whilst digging the Crossrail tunnels.

Furthermore, it’s not clear that all the instrumentation on the test train
are simply strain gauges. They may be 3 axis accelerometers. I know that’s
what our mechanical engineers use when they are characterising structures
under vibration. I suspect they’ll be looking for resonances that the
finite element analysis has failed to get right and also trying to verify
their computer model.

But feel free to contact the Hitachi engineering staff to tell them where
they are going wrong.

Roland Perry <roland@perry.co.uk> wrote:
> This application doesn't need guaranteed continuous data, but I don't
> expect wifi points to affect it, anyway.
>
> I'm pretty sure if we had a show of hands, we'd find several people with
> laptops simultaneously connected by Bluetooth and Wifi (to different
> other devices).
>
> <Waves hand> Bluetooth to mouse and cordless headset, wifi to router.

They typically use the same radio using the same antenna, and therefore they
coordinate. Most chips in phones and laptops are wifi+BT combo chips.
That's not the same as having two transmitters blasting away in close
proximity, which is what you might get in a random radio environment.

Theo

Theo <theom+news@chiark.greenend.org.uk> wrote:
> Roland Perry <roland@perry.co.uk> wrote:
>> This application doesn't need guaranteed continuous data, but I don't
>> expect wifi points to affect it, anyway.
>>
>> I'm pretty sure if we had a show of hands, we'd find several people with
>> laptops simultaneously connected by Bluetooth and Wifi (to different
>> other devices).
>>
>> <Waves hand> Bluetooth to mouse and cordless headset, wifi to router.
>
> They typically use the same radio using the same antenna, and therefore they
> coordinate. Most chips in phones and laptops are wifi+BT combo chips.
> That's not the same as having two transmitters blasting away in close
> proximity, which is what you might get in a random radio environment.

Since Bluetooth and WiFi (some, the popular early WiFi almost exclusively,
802.11b and g) use the same waveband - 2.4 GHz - they didn’t play well
together at first. There were fairly major changes to the BT spec (BT
1.2?) so that just having it on didn’t interfere significantly with the
WiFi service.

Sam

--
The entity formerly known as Sam.Wilson@ed.ac.uk
Spit the dummy to reply

Tweed <usenet.tweed@gmail.com> wrote:
> Roland Perry <roland@perry.co.uk> wrote:
>> In message <scqb63$9ks$1@dont-email.me>, at 22:00:35 on Thu, 15 Jul
>> 2021, Anna Noyd-Dryver <anna@noyd-dryver.com> remarked:
>>
>>>>>>>> The yaw damper fatigue cracking is still being investigated, with strain
>>>>>>>> gauges fitted to two units, one GWR and one LNER.
>>
>>>>>>> I've seen a couple of ECS Paddington to Penzance and back IET round
>>>>>>> trips and wonder if that is this investigation?
>>>>>>
>>>>>> I don't know, but would have thought that it would be better for the tests
>>>>>> to be performed on units in normal customer service, not doing anything out
>>>>>> of the ordinary. After all, these trains had lots of testing before being
>>>>>> introduced into service, which didn't find the fault which showed up in
>>>>>> normal customer service.
>>>>>
>>>>> The strain gauge electrical connections have to go through partly-opened
>>>>> doors, I think, so the unit fitted with the equipment can't operate in
>>>>> service.
>>>>
>>>> Ah, I didn't know that. I assumed it could all be fitted underfloor.
>>>
>>> From the picture I saw, the sensors are fitted around the lifting
>>> bracket/yaw damper area, and the cables fed to inside the train.
>>
>> Meanwhile, the rest of the world has discovered Bluetooth.
>
> Strain gauges need calibrated front end electronics. That exists as off the
> shelf units and that is presumably what is being used. However said units
> are designed to go in benign environments. Clearly it is possible to design
> something to go in a hostile under coach environment, but that requires
> things like power supplies, consideration of where it is to be fitted,
> design of a hostile environment housing, analysis of any safety issues etc.
> That takes weeks or months and you’d be the first to be on here moaning
> that something wasn’t being done. Jury-rigging a test train and running it
> out of passenger service seems to me to be the most expedient way of
> getting rapid results. It is also probably much cheaper than the design
> cycle I mention.
>
> There is perhaps a case for designing a long term instrumentation solution,
> so one train could be properly monitored in service over a number of years.
> Clearly they have issues they don’t fully understand. But that’s a major
> project for another day.
>
>

Here's the test unit
<https://twitter.com/annanoyddryver/status/1416175337348780033?s=21> (pic
from WNXX forum).

I count 19 visible strain gauges on this side, and as AIUI most of the
cracks are underneath, I presume there are more mounted out of sight.

This is a 5-car 802, so can't test all bogie set-ups.

Anna Noyd-Dryver

Anna Noyd-Dryver <anna@noyd-dryver.com> wrote:
> Tweed <usenet.tweed@gmail.com> wrote:
>> Roland Perry <roland@perry.co.uk> wrote:
>>> In message <scqb63$9ks$1@dont-email.me>, at 22:00:35 on Thu, 15 Jul
>>> 2021, Anna Noyd-Dryver <anna@noyd-dryver.com> remarked:
>>>
>>>>>>>>> The yaw damper fatigue cracking is still being investigated, with strain
>>>>>>>>> gauges fitted to two units, one GWR and one LNER.
>>>
>>>>>>>> I've seen a couple of ECS Paddington to Penzance and back IET round
>>>>>>>> trips and wonder if that is this investigation?
>>>>>>>
>>>>>>> I don't know, but would have thought that it would be better for the tests
>>>>>>> to be performed on units in normal customer service, not doing anything out
>>>>>>> of the ordinary. After all, these trains had lots of testing before being
>>>>>>> introduced into service, which didn't find the fault which showed up in
>>>>>>> normal customer service.
>>>>>>
>>>>>> The strain gauge electrical connections have to go through partly-opened
>>>>>> doors, I think, so the unit fitted with the equipment can't operate in
>>>>>> service.
>>>>>
>>>>> Ah, I didn't know that. I assumed it could all be fitted underfloor.
>>>>
>>>> From the picture I saw, the sensors are fitted around the lifting
>>>> bracket/yaw damper area, and the cables fed to inside the train.
>>>
>>> Meanwhile, the rest of the world has discovered Bluetooth.
>>
>> Strain gauges need calibrated front end electronics. That exists as off the
>> shelf units and that is presumably what is being used. However said units
>> are designed to go in benign environments. Clearly it is possible to design
>> something to go in a hostile under coach environment, but that requires
>> things like power supplies, consideration of where it is to be fitted,
>> design of a hostile environment housing, analysis of any safety issues etc.
>> That takes weeks or months and you’d be the first to be on here moaning
>> that something wasn’t being done. Jury-rigging a test train and running it
>> out of passenger service seems to me to be the most expedient way of
>> getting rapid results. It is also probably much cheaper than the design
>> cycle I mention.
>>
>> There is perhaps a case for designing a long term instrumentation solution,
>> so one train could be properly monitored in service over a number of years.
>> Clearly they have issues they don’t fully understand. But that’s a major
>> project for another day.
>>
>>
>
> Here's the test unit
> <https://twitter.com/annanoyddryver/status/1416175337348780033?s=21> (pic
> from WNXX forum).
>
> I count 19 visible strain gauges on this side, and as AIUI most of the
> cracks are underneath, I presume there are more mounted out of sight.
>
> This is a 5-car 802, so can't test all bogie set-ups.
>

Correction; it's a 9-car, 802103.

Apparently two cars have test equipment and instrumentation on them, a
driving car and an engine-fitted car (therefore not one of the cars with
the inside-bearing bogies).

Anna Noyd-Dryver

Anna Noyd-Dryver <anna@noyd-dryver.com> wrote:
> Anna Noyd-Dryver <anna@noyd-dryver.com> wrote:
>> Tweed <usenet.tweed@gmail.com> wrote:
>>> Roland Perry <roland@perry.co.uk> wrote:
>>>> In message <scqb63$9ks$1@dont-email.me>, at 22:00:35 on Thu, 15 Jul
>>>> 2021, Anna Noyd-Dryver <anna@noyd-dryver.com> remarked:
>>>>
>>>>>>>>>> The yaw damper fatigue cracking is still being investigated, with strain
>>>>>>>>>> gauges fitted to two units, one GWR and one LNER.
>>>>
>>>>>>>>> I've seen a couple of ECS Paddington to Penzance and back IET round
>>>>>>>>> trips and wonder if that is this investigation?
>>>>>>>>
>>>>>>>> I don't know, but would have thought that it would be better for the tests
>>>>>>>> to be performed on units in normal customer service, not doing anything out
>>>>>>>> of the ordinary. After all, these trains had lots of testing before being
>>>>>>>> introduced into service, which didn't find the fault which showed up in
>>>>>>>> normal customer service.
>>>>>>>
>>>>>>> The strain gauge electrical connections have to go through partly-opened
>>>>>>> doors, I think, so the unit fitted with the equipment can't operate in
>>>>>>> service.
>>>>>>
>>>>>> Ah, I didn't know that. I assumed it could all be fitted underfloor.
>>>>>
>>>>> From the picture I saw, the sensors are fitted around the lifting
>>>>> bracket/yaw damper area, and the cables fed to inside the train.
>>>>
>>>> Meanwhile, the rest of the world has discovered Bluetooth.
>>>
>>> Strain gauges need calibrated front end electronics. That exists as off the
>>> shelf units and that is presumably what is being used. However said units
>>> are designed to go in benign environments. Clearly it is possible to design
>>> something to go in a hostile under coach environment, but that requires
>>> things like power supplies, consideration of where it is to be fitted,
>>> design of a hostile environment housing, analysis of any safety issues etc.
>>> That takes weeks or months and you’d be the first to be on here moaning
>>> that something wasn’t being done. Jury-rigging a test train and running it
>>> out of passenger service seems to me to be the most expedient way of
>>> getting rapid results. It is also probably much cheaper than the design
>>> cycle I mention.
>>>
>>> There is perhaps a case for designing a long term instrumentation solution,
>>> so one train could be properly monitored in service over a number of years.
>>> Clearly they have issues they don’t fully understand. But that’s a major
>>> project for another day.
>>>
>>>
>>
>> Here's the test unit
>> <https://twitter.com/annanoyddryver/status/1416175337348780033?s=21> (pic
>> from WNXX forum).
>>
>> I count 19 visible strain gauges on this side, and as AIUI most of the
>> cracks are underneath, I presume there are more mounted out of sight.
>>
>> This is a 5-car 802, so can't test all bogie set-ups.
>>
>
> Correction; it's a 9-car, 802103.
>
> Apparently two cars have test equipment and instrumentation on them, a
> driving car and an engine-fitted car (therefore not one of the cars with
> the inside-bearing bogies).
>

Interesting that they chose to instrument a 9-car unit, when a 5-car would
have done, if they're not testing trailers?

In the photo, I was surprised not to see a bundle of wires going through
the open doorway.

Recliner <recliner.usenet@gmail.com> wrote:
> Anna Noyd-Dryver <anna@noyd-dryver.com> wrote:
>> Anna Noyd-Dryver <anna@noyd-dryver.com> wrote:
>>> Tweed <usenet.tweed@gmail.com> wrote:
>>>> Roland Perry <roland@perry.co.uk> wrote:
>>>>> In message <scqb63$9ks$1@dont-email.me>, at 22:00:35 on Thu, 15 Jul
>>>>> 2021, Anna Noyd-Dryver <anna@noyd-dryver.com> remarked:
>>>>>
>>>>>>>>>>> The yaw damper fatigue cracking is still being investigated, with strain
>>>>>>>>>>> gauges fitted to two units, one GWR and one LNER.
>>>>>
>>>>>>>>>> I've seen a couple of ECS Paddington to Penzance and back IET round
>>>>>>>>>> trips and wonder if that is this investigation?
>>>>>>>>>
>>>>>>>>> I don't know, but would have thought that it would be better for the tests
>>>>>>>>> to be performed on units in normal customer service, not doing anything out
>>>>>>>>> of the ordinary. After all, these trains had lots of testing before being
>>>>>>>>> introduced into service, which didn't find the fault which showed up in
>>>>>>>>> normal customer service.
>>>>>>>>
>>>>>>>> The strain gauge electrical connections have to go through partly-opened
>>>>>>>> doors, I think, so the unit fitted with the equipment can't operate in
>>>>>>>> service.
>>>>>>>
>>>>>>> Ah, I didn't know that. I assumed it could all be fitted underfloor.
>>>>>>
>>>>>> From the picture I saw, the sensors are fitted around the lifting
>>>>>> bracket/yaw damper area, and the cables fed to inside the train.
>>>>>
>>>>> Meanwhile, the rest of the world has discovered Bluetooth.
>>>>
>>>> Strain gauges need calibrated front end electronics. That exists as off the
>>>> shelf units and that is presumably what is being used. However said units
>>>> are designed to go in benign environments. Clearly it is possible to design
>>>> something to go in a hostile under coach environment, but that requires
>>>> things like power supplies, consideration of where it is to be fitted,
>>>> design of a hostile environment housing, analysis of any safety issues etc.
>>>> That takes weeks or months and you’d be the first to be on here moaning
>>>> that something wasn’t being done. Jury-rigging a test train and running it
>>>> out of passenger service seems to me to be the most expedient way of
>>>> getting rapid results. It is also probably much cheaper than the design
>>>> cycle I mention.
>>>>
>>>> There is perhaps a case for designing a long term instrumentation solution,
>>>> so one train could be properly monitored in service over a number of years.
>>>> Clearly they have issues they don’t fully understand. But that’s a major
>>>> project for another day.
>>>>
>>>>
>>>
>>> Here's the test unit
>>> <https://twitter.com/annanoyddryver/status/1416175337348780033?s=21> (pic
>>> from WNXX forum).
>>>
>>> I count 19 visible strain gauges on this side, and as AIUI most of the
>>> cracks are underneath, I presume there are more mounted out of sight.
>>>
>>> This is a 5-car 802, so can't test all bogie set-ups.
>>>
>>
>> Correction; it's a 9-car, 802103.
>>
>> Apparently two cars have test equipment and instrumentation on them, a
>> driving car and an engine-fitted car (therefore not one of the cars with
>> the inside-bearing bogies).
>>
>
> Interesting that they chose to instrument a 9-car unit, when a 5-car would
> have done, if they're not testing trailers?
>
> In the photo, I was surprised not to see a bundle of wires going through
> the open doorway.
>
>

That's the cab door and would make using the test unit rather difficult if
it couldn't be properly closed and sealed!

The WNXX post makes mention of certain doors being LOOU because of cables
passing through them, but no pictures; presumably they're carefully routed
past a door which is closed manually and gently and then locked out of use.

Anna Noyd-Dryver

On 16/07/2021 16:58, Recliner wrote:
> <martin.coffee@round-midnight.org.uk> wrote:
>> On 16/07/2021 14:19, Roland Perry wrote:
>>> In message <scrcn1$272$1@dont-email.me>, at 07:32:49 on Fri, 16 Jul
>>> 2021, Tweed <usenet.tweed@gmail.com> remarked:
>>>> Roland Perry <roland@perry.co.uk> wrote:
>>>>> In message <scqb63$9ks$1@dont-email.me>, at 22:00:35 on Thu, 15 Jul
>>>>> 2021, Anna Noyd-Dryver <anna@noyd-dryver.com> remarked:
>>>>>
>>>>>>>>>>> The yaw damper fatigue cracking is still being investigated,
>>>>>>>>>>> with strain
>>>>>>>>>>> gauges fitted to two units, one GWR and one LNER.
>>>>>
>>>>>>>>>> I've seen a couple of ECS Paddington to Penzance and back IET round
>>>>>>>>>> trips and wonder if that is this investigation?
>>>>>>>>>
>>>>>>>>> I don't know, but would have thought that it would be better for
>>>>>>>>> the tests
>>>>>>>>> to be performed on units in normal customer service, not doing
>>>>>>>>> anything out
>>>>>>>>> of the ordinary. After all, these trains had lots of testing
>>>>>>>>> before being
>>>>>>>>> introduced into service, which didn't find the fault which showed
>>>>>>>>> up in
>>>>>>>>> normal customer service.
>>>>>>>>
>>>>>>>> The strain gauge electrical connections have to go through
>>>>>>>> partly-opened
>>>>>>>> doors, I think, so the unit fitted with the equipment can't
>>>>>>>> operate in
>>>>>>>> service.
>>>>>>>
>>>>>>> Ah, I didn't know that. I assumed it could all be fitted underfloor.
>>>>>>
>>>>>> From the picture I saw, the sensors are fitted around the lifting
>>>>>> bracket/yaw damper area, and the cables fed to inside the train.
>>>>>
>>>>> Meanwhile, the rest of the world has discovered Bluetooth.
>>>>
>>>> Strain gauges need calibrated front end electronics. That exists as
>>>> off the
>>>> shelf units and that is presumably what is being used. However said units
>>>> are designed to go in benign environments.
>>>
>>> No-one makes any strain-gauge equipment capable of operating in other
>>> than a molly-coddled indoor environment? Doesn't pass my sniff test.
>>>
>> I've used strain guages on the most extreme of military equipment where
>> an IET is nothing in comparison. You can shove the gauges themselves
>> pretty well any environment however the recording equipment is more
>> sensitive and will have to be calibrated in for this trial.
>>
>> I would not use Bluetooth for a number of reasons. There will almost
>> certainly be a random loss of data, it might be small but something
>> significant might be lost. The recording equipment has to be calibrated
>> and the signals concerned might be minute so I would want that equipment
>> mounted within the train. I would not want calibrated Bluetooth
>> equipment mounted on the outside of the train, some of those sensors
>> will be mounted on the bogies so the vibration will be quite high which
>> is not good for calibrated electronics and an unnecessary risk to the
>> trials. I also suspect they're not just instrumented one yaw lifting
>> bracket/yaw damper area but at least several along the train so you're
>> be operating quite a few Bluetooth interfaces which doesn't always go well.
>
> Yes, a 9-car IET has three types of yaw damper arm, so at least three cars
> would need instrumenting. But it might be wiser to instrument at least two
> cars of each type. And I'd have thought both bogies in each carriage should
> be covered.

It will be an expensive trial which takes a serviceable unit out of
passenger service so I would be surprised if they don't record at least
twice of each permutation and combination.
> The good news is that the equipment can all be body-mounted, with nothing
> on the bogies. The cracks are all on the body supports.

I was looking closely at the dampers on an IET in Parkway on Tuesday and
have that feeling they will instrumentate at both ends of the of the
dampers. It's far better to record too much rather than decide it was
needed after all. If something's wrong at one end they'll want to
consider the other as well. Anyway I'm sure the ORR will want the
design of the mounts on the bogies to be re-validated. I would be very
disappointed with them if they don't.

>>
>> Speed is of the essence in this so why go to unnecessary complexity
>> which the added risk of failure when the simple and quickest solution is
>> possible and will give the necessary data.
>
> Yes, definitely.
>
>>
>> I suspect that permanent monitoring equipment will be fitted to a few
>> units in the medium term and I'm sure that will be a basic wired system
>> as well.
>>
>
> Yes, that would be a good idea.
>

<martin.coffee@round-midnight.org.uk> wrote:
> On 16/07/2021 16:58, Recliner wrote:
>> <martin.coffee@round-midnight.org.uk> wrote:
>>> On 16/07/2021 14:19, Roland Perry wrote:
>>>> In message <scrcn1$272$1@dont-email.me>, at 07:32:49 on Fri, 16 Jul
>>>> 2021, Tweed <usenet.tweed@gmail.com> remarked:
>>>>> Roland Perry <roland@perry.co.uk> wrote:
>>>>>> In message <scqb63$9ks$1@dont-email.me>, at 22:00:35 on Thu, 15 Jul
>>>>>> 2021, Anna Noyd-Dryver <anna@noyd-dryver.com> remarked:
>>>>>>
>>>>>>>>>>>> The yaw damper fatigue cracking is still being investigated,
>>>>>>>>>>>> with strain
>>>>>>>>>>>> gauges fitted to two units, one GWR and one LNER.
>>>>>>
>>>>>>>>>>> I've seen a couple of ECS Paddington to Penzance and back IET round
>>>>>>>>>>> trips and wonder if that is this investigation?
>>>>>>>>>>
>>>>>>>>>> I don't know, but would have thought that it would be better for
>>>>>>>>>> the tests
>>>>>>>>>> to be performed on units in normal customer service, not doing
>>>>>>>>>> anything out
>>>>>>>>>> of the ordinary. After all, these trains had lots of testing
>>>>>>>>>> before being
>>>>>>>>>> introduced into service, which didn't find the fault which showed
>>>>>>>>>> up in
>>>>>>>>>> normal customer service.
>>>>>>>>>
>>>>>>>>> The strain gauge electrical connections have to go through
>>>>>>>>> partly-opened
>>>>>>>>> doors, I think, so the unit fitted with the equipment can't
>>>>>>>>> operate in
>>>>>>>>> service.
>>>>>>>>
>>>>>>>> Ah, I didn't know that. I assumed it could all be fitted underfloor.
>>>>>>>
>>>>>>> From the picture I saw, the sensors are fitted around the lifting
>>>>>>> bracket/yaw damper area, and the cables fed to inside the train.
>>>>>>
>>>>>> Meanwhile, the rest of the world has discovered Bluetooth.
>>>>>
>>>>> Strain gauges need calibrated front end electronics. That exists as
>>>>> off the
>>>>> shelf units and that is presumably what is being used. However said units
>>>>> are designed to go in benign environments.
>>>>
>>>> No-one makes any strain-gauge equipment capable of operating in other
>>>> than a molly-coddled indoor environment? Doesn't pass my sniff test.
>>>>
>>> I've used strain guages on the most extreme of military equipment where
>>> an IET is nothing in comparison. You can shove the gauges themselves
>>> pretty well any environment however the recording equipment is more
>>> sensitive and will have to be calibrated in for this trial.
>>>
>>> I would not use Bluetooth for a number of reasons. There will almost
>>> certainly be a random loss of data, it might be small but something
>>> significant might be lost. The recording equipment has to be calibrated
>>> and the signals concerned might be minute so I would want that equipment
>>> mounted within the train. I would not want calibrated Bluetooth
>>> equipment mounted on the outside of the train, some of those sensors
>>> will be mounted on the bogies so the vibration will be quite high which
>>> is not good for calibrated electronics and an unnecessary risk to the
>>> trials. I also suspect they're not just instrumented one yaw lifting
>>> bracket/yaw damper area but at least several along the train so you're
>>> be operating quite a few Bluetooth interfaces which doesn't always go well.
>>
>> Yes, a 9-car IET has three types of yaw damper arm, so at least three cars
>> would need instrumenting. But it might be wiser to instrument at least two
>> cars of each type. And I'd have thought both bogies in each carriage should
>> be covered.
>
> It will be an expensive trial which takes a serviceable unit out of
> passenger service so I would be surprised if they don't record at least
> twice of each permutation and combination.
>> The good news is that the equipment can all be body-mounted, with nothing
>> on the bogies. The cracks are all on the body supports.
>
> I was looking closely at the dampers on an IET in Parkway on Tuesday and
> have that feeling they will instrumentate at both ends of the of the
> dampers. It's far better to record too much rather than decide it was
> needed after all. If something's wrong at one end they'll want to
> consider the other as well. Anyway I'm sure the ORR will want the
> design of the mounts on the bogies to be re-validated. I would be very
> disappointed with them if they don't.

The cracks are in the body-mounted castings to which the yaw damper arms
are bolted. There aren't any reported problems in the yaw dampers
themselves, nor in the bogies.

I'll trot out my pet theory again: the problems are due to the over-length
IET bodies, which are more stressed as a result, and have more yaw to
handle.

On Sat, 17 Jul 2021 01:27:41 +0100,
martin.coffee@round-midnight.org.uk wrote:

>I was looking closely at the dampers on an IET in Parkway on Tuesday and
> have that feeling they will instrumentate at both ends of the of the
>dampers. It's far better to record too much rather than decide it was
>needed after all. If something's wrong at one end they'll want to
>consider the other as well. Anyway I'm sure the ORR will want the
>design of the mounts on the bogies to be re-validated. I would be very
>disappointed with them if they don't.

Do other Hitachi units have the same problem? Either in the UK or
elsewhere?

Christopher A. Lee <c.lee@fairpoint.net> wrote:
> On Sat, 17 Jul 2021 01:27:41 +0100,
> martin.coffee@round-midnight.org.uk wrote:
>
>> I was looking closely at the dampers on an IET in Parkway on Tuesday and
>> have that feeling they will instrumentate at both ends of the of the
>> dampers. It's far better to record too much rather than decide it was
>> needed after all. If something's wrong at one end they'll want to
>> consider the other as well. Anyway I'm sure the ORR will want the
>> design of the mounts on the bogies to be re-validated. I would be very
>> disappointed with them if they don't.
>
> Do other Hitachi units have the same problem? Either in the UK or
> elsewhere?
>

I don't think so.

In message <PH*z7gpy@news.chiark.greenend.org.uk>, at 18:01:25 on Fri,
16 Jul 2021, Theo <theom+news@chiark.greenend.org.uk> remarked:
>Roland Perry <roland@perry.co.uk> wrote:
>> This application doesn't need guaranteed continuous data, but I don't
>> expect wifi points to affect it, anyway.
>>
>> I'm pretty sure if we had a show of hands, we'd find several people with
>> laptops simultaneously connected by Bluetooth and Wifi (to different
>> other devices).
>>
>> <Waves hand> Bluetooth to mouse and cordless headset, wifi to router.
>
>They typically use the same radio using the same antenna, and therefore they
>coordinate. Most chips in phones and laptops are wifi+BT combo chips.
>That's not the same as having two transmitters blasting away in close
>proximity, which is what you might get in a random radio environment.

I've tended to use Bluetooth dongles, not least because you at get some
driver software that'll probably work - unlike the dreadful BT software
I experienced bundled with laptops.

The BT "strain gauge sender" I linked to claims a range of up to
90metres, and I'm still not clear which wifi hotspots are expected to be
interfering. If they are the ones in stations, then *even if* that
interrupts the data stream for 0.5% of the time, does that mean the
exercise is futile?
--
Roland Perry

In message <scsbok$ihe$1@dont-email.me>, at 16:22:44 on Fri, 16 Jul
2021, Tweed <usenet.tweed@gmail.com> remarked:
>Roland Perry <roland@perry.co.uk> wrote:
>> In message <scs23m$krh$1@dont-email.me>, at 13:37:58 on Fri, 16 Jul
>> 2021, Tweed <usenet.tweed@gmail.com> remarked:
>>> Roland Perry <roland@perry.co.uk> wrote:
>>>> In message <scrcn1$272$1@dont-email.me>, at 07:32:49 on Fri, 16 Jul
>>>> 2021, Tweed <usenet.tweed@gmail.com> remarked:
>>>>> Roland Perry <roland@perry.co.uk> wrote:
>>>>>> In message <scqb63$9ks$1@dont-email.me>, at 22:00:35 on Thu, 15 Jul
>>>>>> 2021, Anna Noyd-Dryver <anna@noyd-dryver.com> remarked:
>>>>>>
>>>>>>>>>>>> The yaw damper fatigue cracking is still being
>>>>>>>>>>>>investigated, with strain gauges fitted to two units, one
>>>>>>>>>>>>
>>>>>>
>>>>>>>>>>> I've seen a couple of ECS Paddington to Penzance and back IET round
>>>>>>>>>>> trips and wonder if that is this investigation?
>>>>>>>>>>
>>>>>>>>>> I don't know, but would have thought that it would be better
>>>>>>>>>> the tests to be performed on units in normal customer
>>>>>>>>>>service, not doing anything out of the ordinary. After all,
>>>>>>>>>>these trains had lots of testing before being introduced
>>>>>>>>>>into service, which didn't find the fault which showed up in normal customer service.
>>>>>>>>>
>>>>>>>>> The strain gauge electrical connections have to go through
>>>>>>>>>partly-opened doors, I think, so the unit fitted with the
>>>>>>>>>equipment can't operate in service.
>>>>>>>>
>>>>>>>> Ah, I didn't know that. I assumed it could all be fitted underfloor.
>>>>>>>
>>>>>>> From the picture I saw, the sensors are fitted around the lifting
>>>>>>> bracket/yaw damper area, and the cables fed to inside the train.
>>>>>>
>>>>>> Meanwhile, the rest of the world has discovered Bluetooth.
>>>>>
>>>>> Strain gauges need calibrated front end electronics. That exists
>>>>>as off the
>>>>> shelf units and that is presumably what is being used. However said units
>>>>> are designed to go in benign environments.
>>>>
>>>> No-one makes any strain-gauge equipment capable of operating in other
>>>> than a molly-coddled indoor environment? Doesn't pass my sniff test.
>>>>
>>>
>>> But you’ve neglected all the rest of it. You need power, a housing, method
>>> of mounting, a detailed safety analysis that all of this you’ve
>>>slung under
>>> the train isn’t going to come off and damage something else. You’ve also
>>> now got something that’s hard to access and thus hard to fix if it goes
>>> wrong. All this to promote your pet Bluetooth proposition. If this were to
>>> be something that you needed in service for many years to come you’d
>>> perhaps put the effort in. But this is an experimental setup to get some
>>> data to hopefully fix a problem quickly. You’ve yet to explain what major
>>> benefits your Bluetooth solution brings. All sorts of things are available
>>> for hostile conditions, but it takes time and money, sometimes a lot of
>>> money, to tailor a solution.
>>
>> Or just buy it in:
>>
>> <https://appmeas.co.uk/products/instrumentation/bluetooth-strain-gauge-
>> transmitter-b24-ssb/>
>
>As far as I can tell from its rather poor spec sheet, it’s single channel
>with a very low sample rate. You’d need loads of them and it’s not obvious
>what maximum frequency they are interested in. I suspect more than 1 Hz.
>The unit has no vibration spec for the electronics.

That's just an indicative example to show the class of product exists.

>You’d still have to make a safety case for mounting them outside of
>the passenger accommodation and probably much more in that respect if
>you wanted to run the train in passenger carrying service. It’s not
>obvious what problem you are trying to solve with Bluetooth.

It was the duct-taping of the wires from the strain gauges around the
outside of the train and through a partly-open door.

>Furthermore, it’s not clear that all the instrumentation on the test train
>are simply strain gauges. They may be 3 axis accelerometers.

That's a big change to the brief but it's all just data streams.

>But feel free to contact the Hitachi engineering staff to tell them where
>they are going wrong.

Their problem as far as I can see is the pace at which the investigation
(and fix) is proceeding. But not doubt they have deep pockets.
--
Roland Perry

In message <scsabi$vlv$1@dont-email.me>, at 15:58:42 on Fri, 16 Jul
2021, Recliner <recliner.usenet@gmail.com> remarked:

>> I would not use Bluetooth for a number of reasons. There will almost
>> certainly be a random loss of data, it might be small but something
>> significant might be lost. The recording equipment has to be calibrated
>> and the signals concerned might be minute so I would want that equipment
>> mounted within the train. I would not want calibrated Bluetooth
>> equipment mounted on the outside of the train, some of those sensors
>> will be mounted on the bogies so the vibration will be quite high which
>> is not good for calibrated electronics and an unnecessary risk to the
>> trials. I also suspect they're not just instrumented one yaw lifting
>> bracket/yaw damper area but at least several along the train so you're
>> be operating quite a few Bluetooth interfaces which doesn't always go well.
>
>Yes, a 9-car IET has three types of yaw damper arm, so at least three cars
>would need instrumenting. But it might be wiser to instrument at least two
>cars of each type. And I'd have thought both bogies in each carriage should
>be covered.
>
>The good news is that the equipment can all be body-mounted, with nothing
>on the bogies. The cracks are all on the body supports.

Yes, I was a bit surprised at the assertion of sensors mounted on
bogies, too. The wires would have to be quite long and flexible to
accommodate the movement between the bogie itself and the carriage,
before then being duct-taped around the side and through the partly-open
door.
--
Roland Perry

Roland Perry <roland@perry.co.uk> wrote:
> In message <scsabi$vlv$1@dont-email.me>, at 15:58:42 on Fri, 16 Jul
> 2021, Recliner <recliner.usenet@gmail.com> remarked:
>
>>> I would not use Bluetooth for a number of reasons. There will almost
>>> certainly be a random loss of data, it might be small but something
>>> significant might be lost. The recording equipment has to be calibrated
>>> and the signals concerned might be minute so I would want that equipment
>>> mounted within the train. I would not want calibrated Bluetooth
>>> equipment mounted on the outside of the train, some of those sensors
>>> will be mounted on the bogies so the vibration will be quite high which
>>> is not good for calibrated electronics and an unnecessary risk to the
>>> trials. I also suspect they're not just instrumented one yaw lifting
>>> bracket/yaw damper area but at least several along the train so you're
>>> be operating quite a few Bluetooth interfaces which doesn't always go well.
>>
>> Yes, a 9-car IET has three types of yaw damper arm, so at least three cars
>> would need instrumenting. But it might be wiser to instrument at least two
>> cars of each type. And I'd have thought both bogies in each carriage should
>> be covered.
>>
>> The good news is that the equipment can all be body-mounted, with nothing
>> on the bogies. The cracks are all on the body supports.
>
> Yes, I was a bit surprised at the assertion of sensors mounted on
> bogies, too. The wires would have to be quite long and flexible to
> accommodate the movement between the bogie itself and the carriage,
> before then being duct-taped around the side and through the partly-open
> door.

Not that there are any flexible electrical connections to the bogies
already, of course…

Anna Noyd-Dryver

Anna Noyd-Dryver <anna@noyd-dryver.com> wrote:
> Roland Perry <roland@perry.co.uk> wrote:
>> In message <scsabi$vlv$1@dont-email.me>, at 15:58:42 on Fri, 16 Jul
>> 2021, Recliner <recliner.usenet@gmail.com> remarked:
>>
>>>> I would not use Bluetooth for a number of reasons. There will almost
>>>> certainly be a random loss of data, it might be small but something
>>>> significant might be lost. The recording equipment has to be calibrated
>>>> and the signals concerned might be minute so I would want that equipment
>>>> mounted within the train. I would not want calibrated Bluetooth
>>>> equipment mounted on the outside of the train, some of those sensors
>>>> will be mounted on the bogies so the vibration will be quite high which
>>>> is not good for calibrated electronics and an unnecessary risk to the
>>>> trials. I also suspect they're not just instrumented one yaw lifting
>>>> bracket/yaw damper area but at least several along the train so you're
>>>> be operating quite a few Bluetooth interfaces which doesn't always go well.
>>>
>>> Yes, a 9-car IET has three types of yaw damper arm, so at least three cars
>>> would need instrumenting. But it might be wiser to instrument at least two
>>> cars of each type. And I'd have thought both bogies in each carriage should
>>> be covered.
>>>
>>> The good news is that the equipment can all be body-mounted, with nothing
>>> on the bogies. The cracks are all on the body supports.
>>
>> Yes, I was a bit surprised at the assertion of sensors mounted on
>> bogies, too. The wires would have to be quite long and flexible to
>> accommodate the movement between the bogie itself and the carriage,
>> before then being duct-taped around the side and through the partly-open
>> door.
>
> Not that there are any flexible electrical connections to the bogies
> already, of course…
>
>
> Anna Noyd-Dryver
>
>

I’m not a mechanical engineer, but do observe what my mechanical engineer
colleagues get up to. Although all the failures of the structure are on the
fixed structure, it wouldn’t surprise me if you also instrumented the bogie
with accelerometers. This is to gain an understanding of the driving forces
that get transmitted up into the fixed structure. I know when things are
put on a shaker table both the table and the device under test are
instrumented. And again, I’m fairly sure they’d want accelerometers as part
of the sensor set up. It’s the dynamic forces that cause the cracking.

In message <scu1pp$9n$1@dont-email.me>, at 07:44:57 on Sat, 17 Jul 2021,
Tweed <usenet.tweed@gmail.com> remarked:
>Anna Noyd-Dryver <anna@noyd-dryver.com> wrote:
>> Roland Perry <roland@perry.co.uk> wrote:
>>> In message <scsabi$vlv$1@dont-email.me>, at 15:58:42 on Fri, 16 Jul
>>> 2021, Recliner <recliner.usenet@gmail.com> remarked:
>>>
>>>>> I would not use Bluetooth for a number of reasons. There will almost
>>>>> certainly be a random loss of data, it might be small but something
>>>>> significant might be lost. The recording equipment has to be calibrated
>>>>> and the signals concerned might be minute so I would want that equipment
>>>>> mounted within the train. I would not want calibrated Bluetooth
>>>>> equipment mounted on the outside of the train, some of those sensors
>>>>> will be mounted on the bogies so the vibration will be quite high which
>>>>> is not good for calibrated electronics and an unnecessary risk to the
>>>>> trials. I also suspect they're not just instrumented one yaw lifting
>>>>> bracket/yaw damper area but at least several along the train so you're
>>>>> be operating quite a few Bluetooth interfaces which doesn't always
>>>>>go well.
>>>>
>>>> Yes, a 9-car IET has three types of yaw damper arm, so at least three cars
>>>> would need instrumenting. But it might be wiser to instrument at least two
>>>> cars of each type. And I'd have thought both bogies in each carriage should
>>>> be covered.
>>>>
>>>> The good news is that the equipment can all be body-mounted, with nothing
>>>> on the bogies. The cracks are all on the body supports.
>>>
>>> Yes, I was a bit surprised at the assertion of sensors mounted on
>>> bogies, too. The wires would have to be quite long and flexible to
>>> accommodate the movement between the bogie itself and the carriage,
>>> before then being duct-taped around the side and through the partly-open
>>> door.
>>
>> Not that there are any flexible electrical connections to the bogies
>> already, of course…

But are they temporary ones duck-taped on the body and through a
partially open door?

>I’m not a mechanical engineer, but do observe what my mechanical engineer
>colleagues get up to. Although all the failures of the structure are on the
>fixed structure, it wouldn’t surprise me if you also instrumented the bogie
>with accelerometers.

I's not about surprise, but what they are actually doing.

--
Roland Perry

Roland Perry <roland@perry.co.uk> wrote:
> In message <scpq9d$g9h$1@dont-email.me>, at 17:12:13 on Thu, 15 Jul
> 2021, Anna Noyd-Dryver <anna@noyd-dryver.com> remarked:
>> <martin.coffee@round-midnight.org.uk> wrote:
>>>
>>> https://www.railadvent.co.uk/2021/07/gatwick-express-trains-sent-to-gre
>>> at-western-railway-in-wake-of-class-800-cracks.html
>>>
>>
>> I spotted some red ones at West Ealing sidings yesterday.
>>
>>> The London Cardiff service is still reduced by 50% but most of the
>>> window seats were occupied on the two off-peak services I used earlier
>>> in the week. I know Johnson wont agree but I reckon we've reached the
>>> point where Saturday and peak services need to be reinstated.
>>>
>>> Does anyone know the latest poorly IET statistics or news? I cannot
>>> find anything recent.
>>>
>>
>> This was from WNXX forum (various posters) on 19/6 (I haven't checked again
>> recently):
>>
>> <quote>
>>
>> Whats the current status of GWR IET availabilty. How many sets available vs
>> rqrd for diagrams?
>>
>> 55 sets for 60 diagrams with 1 unit diesel only.
>>
>> How many sets in the fleet?
>>
>> 93 with about 80 in service on a weekday in normal times.
>>
>> At present there are 19 GWR sets out with Yaw Bolster or Lifting Bracket
>> crack related issues - 11 x 800 5 car, 4 x 800 9 car and 4 x 802 5 car. In
>> addition 802103 is being fitted up as the strain gauge test unit. Over the
>> weekend another issue appeared, this time with the deflector plate mounting
>> brackets (cracking) which has currently sidelined 1 x 800 5 car and 2 x 802
>> 5 car. How long all these units are going to be out for isn't yet known.
>>
>> GWR have been operating a 60-65 unit daily requirement, some of which are
>> traffic spares. In normal times that would be 80 units, none of which are
>> traffic spares. There is no need to panic now as the unit attrition rate
>> isn't severe (about one every 7 -14 days)
>>
>> </quote>
>>
>> This is without any actual repairs to units, just monitoring of the cracks.
>
> Must be costing Hitachi a fortune in penalties. And clearly fixing the
> problem isn't easy (or they would have done by now).
>

Talking about high costs, the latest MR (arrived today) reports that
several vehicles may have to be replaced from 800026 and 802005, as such
large body sections were cut away for analysis that it won't be viable to
weld in new sections. It's unclear how many will need to be replaced.

It's now thought that all the 800, 801 and 802 sets in service (182 sets
with four operators) will eventually develop the cracks, so Hitachi is to
set up repair bases at Eastleigh and Newton Aycliffe. The 5-car 800s will
be first in line for the repairs, as they're the worst affected.

Unsurprisingly, the 24m long EMR 810s are not expected to be affected.

On Sat, 17 Jul 2021 15:20:20 -0000 (UTC)
Recliner <recliner.usenet@gmail.com> wrote:
>Talking about high costs, the latest MR (arrived today) reports that
>several vehicles may have to be replaced from 800026 and 802005, as such
>large body sections were cut away for analysis that it won't be viable to
>weld in new sections. It's unclear how many will need to be replaced.
>
>It's now thought that all the 800, 801 and 802 sets in service (182 sets
>with four operators) will eventually develop the cracks, so Hitachi is to
>set up repair bases at Eastleigh and Newton Aycliffe. The 5-car 800s will
>be first in line for the repairs, as they're the worst affected.

Sounds like the 8xx series is slowly changing from the best of railway tech
into an absolute turkey. Its a shame, but I find it hard to believe an
experienced railway builder like Hitachi couldn't forsee this problem. Its
hardly some high tech never-done-before engineering. Corners cut in design
to keep the tender price down perhaps?

<MrSpud_e2v98p@w3w6mngetumx5n9ivmowik.gov> wrote:
> On Sat, 17 Jul 2021 15:20:20 -0000 (UTC)
> Recliner <recliner.usenet@gmail.com> wrote:
>> Talking about high costs, the latest MR (arrived today) reports that
>> several vehicles may have to be replaced from 800026 and 802005, as such
>> large body sections were cut away for analysis that it won't be viable to
>> weld in new sections. It's unclear how many will need to be replaced.
>>
>> It's now thought that all the 800, 801 and 802 sets in service (182 sets
>> with four operators) will eventually develop the cracks, so Hitachi is to
>> set up repair bases at Eastleigh and Newton Aycliffe. The 5-car 800s will
>> be first in line for the repairs, as they're the worst affected.
>
> Sounds like the 8xx series is slowly changing from the best of railway tech
> into an absolute turkey. Its a shame, but I find it hard to believe an
> experienced railway builder like Hitachi couldn't forsee this problem. Its
> hardly some high tech never-done-before engineering.

The problems seem to be because the DfT demanded the unusually long, thin
26m body. UK loading gauge (effectively, narrow gauge) bodies aren't
usually more than 23m long. That seems to have led to extra stresses around
the bogie bolsters. It's not clear if the latest cracks, in the coupler
plates, are also a consequence of the longer overhang, and consequently
greater movement at the couplers due to the over-long bodies.

> Corners cut in design to keep the tender price down perhaps?

No, far from it. Hitachi didn't sell the trains, but supplies them under a
very high priced service contract (the DfT's economy-minded civil
servant-procured trains are costing about twice as much as if they'd been
supplied by a money-grabbing ROSCO).

Any unreliability or maintenance issues cost Hitachi, not the customer, but
it charges so much for them that it's probably still in the bkack.

On Sat, 17 Jul 2021 15:49:32 -0000 (UTC)
Recliner <recliner.usenet@gmail.com> wrote:
><MrSpud_e2v98p@w3w6mngetumx5n9ivmowik.gov> wrote:
>> On Sat, 17 Jul 2021 15:20:20 -0000 (UTC)
>> Recliner <recliner.usenet@gmail.com> wrote:
>>> Talking about high costs, the latest MR (arrived today) reports that
>>> several vehicles may have to be replaced from 800026 and 802005, as such
>>> large body sections were cut away for analysis that it won't be viable to
>>> weld in new sections. It's unclear how many will need to be replaced.
>>>
>>> It's now thought that all the 800, 801 and 802 sets in service (182 sets
>>> with four operators) will eventually develop the cracks, so Hitachi is to
>>> set up repair bases at Eastleigh and Newton Aycliffe. The 5-car 800s will
>>> be first in line for the repairs, as they're the worst affected.
>>
>> Sounds like the 8xx series is slowly changing from the best of railway tech
>> into an absolute turkey. Its a shame, but I find it hard to believe an
>> experienced railway builder like Hitachi couldn't forsee this problem. Its
>> hardly some high tech never-done-before engineering.
>
>The problems seem to be because the DfT demanded the unusually long, thin
>26m body. UK loading gauge (effectively, narrow gauge) bodies aren't
>usually more than 23m long. That seems to have led to extra stresses around
>the bogie bolsters. It's not clear if the latest cracks, in the coupler
>plates, are also a consequence of the longer overhang, and consequently
>greater movement at the couplers due to the over-long bodies.

Sure, but all this can be and should have been modelled and frankly its basic
engineering. It doesn't say a lot about Hitachis railway engineering division
that neither the engineers or the modelling computers forsee this.

>Any unreliability or maintenance issues cost Hitachi, not the customer, but
>it charges so much for them that it's probably still in the bkack.

More than likely.

<MrSpud_pw@245n.co.uk> wrote:
> On Sat, 17 Jul 2021 15:49:32 -0000 (UTC)
> Recliner <recliner.usenet@gmail.com> wrote:
>> <MrSpud_e2v98p@w3w6mngetumx5n9ivmowik.gov> wrote:
>>> On Sat, 17 Jul 2021 15:20:20 -0000 (UTC)
>>> Recliner <recliner.usenet@gmail.com> wrote:
>>>> Talking about high costs, the latest MR (arrived today) reports that
>>>> several vehicles may have to be replaced from 800026 and 802005, as such
>>>> large body sections were cut away for analysis that it won't be viable to
>>>> weld in new sections. It's unclear how many will need to be replaced.
>>>>
>>>> It's now thought that all the 800, 801 and 802 sets in service (182 sets
>>>> with four operators) will eventually develop the cracks, so Hitachi is to
>>>> set up repair bases at Eastleigh and Newton Aycliffe. The 5-car 800s will
>>>> be first in line for the repairs, as they're the worst affected.
>>>
>>> Sounds like the 8xx series is slowly changing from the best of railway tech
>>> into an absolute turkey. Its a shame, but I find it hard to believe an
>>> experienced railway builder like Hitachi couldn't forsee this problem. Its
>>> hardly some high tech never-done-before engineering.
>>
>> The problems seem to be because the DfT demanded the unusually long, thin
>> 26m body. UK loading gauge (effectively, narrow gauge) bodies aren't
>> usually more than 23m long. That seems to have led to extra stresses around
>> the bogie bolsters. It's not clear if the latest cracks, in the coupler
>> plates, are also a consequence of the longer overhang, and consequently
>> greater movement at the couplers due to the over-long bodies.
>
> Sure, but all this can be and should have been modelled and frankly its basic
> engineering. It doesn't say a lot about Hitachis railway engineering division
> that neither the engineers or the modelling computers forsee this.
>
>> Any unreliability or maintenance issues cost Hitachi, not the customer, but
>> it charges so much for them that it's probably still in the bkack.
>
> More than likely.
>
>

You have a touching faith in modelling……..

On Sat, 17 Jul 2021 16:19:11 -0000 (UTC), Tweed <usenet.tweed@gmail.com> wrote:

><MrSpud_pw@245n.co.uk> wrote:
>> On Sat, 17 Jul 2021 15:49:32 -0000 (UTC)
>> Recliner <recliner.usenet@gmail.com> wrote:
>>> <MrSpud_e2v98p@w3w6mngetumx5n9ivmowik.gov> wrote:
>>>> On Sat, 17 Jul 2021 15:20:20 -0000 (UTC)
>>>> Recliner <recliner.usenet@gmail.com> wrote:
>>>>> Talking about high costs, the latest MR (arrived today) reports that
>>>>> several vehicles may have to be replaced from 800026 and 802005, as such
>>>>> large body sections were cut away for analysis that it won't be viable to
>>>>> weld in new sections. It's unclear how many will need to be replaced.
>>>>>
>>>>> It's now thought that all the 800, 801 and 802 sets in service (182 sets
>>>>> with four operators) will eventually develop the cracks, so Hitachi is to
>>>>> set up repair bases at Eastleigh and Newton Aycliffe. The 5-car 800s will
>>>>> be first in line for the repairs, as they're the worst affected.
>>>>
>>>> Sounds like the 8xx series is slowly changing from the best of railway tech
>>>> into an absolute turkey. Its a shame, but I find it hard to believe an
>>>> experienced railway builder like Hitachi couldn't forsee this problem. Its
>>>> hardly some high tech never-done-before engineering.
>>>
>>> The problems seem to be because the DfT demanded the unusually long, thin
>>> 26m body. UK loading gauge (effectively, narrow gauge) bodies aren't
>>> usually more than 23m long. That seems to have led to extra stresses around
>>> the bogie bolsters. It's not clear if the latest cracks, in the coupler
>>> plates, are also a consequence of the longer overhang, and consequently
>>> greater movement at the couplers due to the over-long bodies.
>>
>> Sure, but all this can be and should have been modelled and frankly its basic
>> engineering. It doesn't say a lot about Hitachis railway engineering division
>> that neither the engineers or the modelling computers forsee this.
>>
>>> Any unreliability or maintenance issues cost Hitachi, not the customer, but
>>> it charges so much for them that it's probably still in the bkack.
>>
>> More than likely.
>>
>>
>
>You have a touching faith in modelling……..

Neil does have a very good point that an experienced train builder like Hitachi really should be able to design/test new
trains that don't quickly develop expensive cracks in multiple places. There are suggestions that they chose the wrong
alloy for one component, failed to heat treat it properly after the welding, and obviously messed up the finite element
modelling. Those look like novice mistakes (I was performing stress creep cycle analysis using finite element models
almost 50 years ago, and thought things had moved on a bit since then).

It's not as if it's a revolutionary new design: the A train family has been in service for decades, and in service in
the UK for over a decade. Yes, there are some new elements in the IETs, but surely Hitachi knows the design well enough
by now to be able to evolve it without these embarrassing problems.