2012 Q1 Two Methods of commissioning new equipment

[Hort]

Hi I am sitting paper 1 this year and have attempted Q1 from last year's paper.

[PJW]

I am busy this weekend, so will be next week before I get a chance; perhaps someone else might do sooner.

Hi I am sitting paper 1 this year and have attempted Q1 from last year's paper.

[Peter]

Hi I am sitting paper 1 this year and have attempted Q1 from last year's paper.

You have talked about programme risks and costs but very little about technical risks and the relative engineering costs of the two. You have assumed that they reader knows about the complexity of doing multiple stage work. He may well know this, but he will not give you any credit unless you tell him that you know about it. So, particularly in your answer to section b, saying about the difficulty of designing many stages before any of them being commissioned without giving details of what the issues and risks may me will not get very many marks.

An important consideration may be the ability to find sufficient staff to deliver a Big Bang commissioning.

You make reference to major commissioning costing less, but what you really mean is at the engineering aspect may use smaller amounts of resource. The cost to the customer includes the TOC costs that you raise at the start. Therefore be careful about what you are saying costs less. A factor for consideration is the relative costs of the different elements.

Some pedantic points - soak testing is not going to save you any testing on the commissioning. It merely gives you confidence that equipment is likely to be reliable. You still need to do your commissioning tests when it comes into use.
On the S&C being laid in, you have jumped to the possible solution of those that need some interim point detection. Depending on the timescale, this may well be unnecessary. Strictly speaking, occupying a track will not stop a route being set, it will stop an aspect clearing but assuming all the opposing route locking is normal, the route can be set.

Peter

[jenni.joseph9]

Hi,

I would like to know more about this topic.

Can anyone please help me out to get more information in the area of Extended closure/overnight and weekend closures.

Thanks

[PJW]

In the UK the longest "non-disruptive" possession that can generally be arranged is from about 01:00 after the end of the Saturday service to around 06:30 at the beginning of Sunday, but of course it does vary around the network depending on precise timetable. Mid week nights are typically much shorter- perhaps 01:00 to 04:00 but may be an hour or two longer- it largely depends where the rolling stock for the commuter service is stabled.

Sometimes it is possible to arrange to replace trains by buses from earlier in an evening, for example from 23:00.or in a few cases there are diversionary routes or 4-track railway when only 2 tracks are needed for the service late at night / early in the morning and the other two can be under possession longer.

Otherwise to get longer to undertake work, the travelling public must be inconvenienced further- perhaps by the use of buses or long railway detours all day on Sunday, so that engineers can be given a longer uninterrupted access- 54 hour and even 72 hour possessions can be arranged given the need and enough notice. Periods such as Christmas and Easter and other Bank Holiday weekends when most people take a long weekend are possibilities for this (but much hated by those who expect to travel by train then). This reflects that commuting to/from work is a major use of the UK railways; conversely in Eire the railway is most used over the holiday weekends, so for them such times are a bad time to undertake work.

The question really is whether it is better to divide the work into lots of small chunks that can each be done in a relatively short period, but needing very many of them- perhaps every weekend for a period of years- or is it best to concentrate all that effort into a closure of the line for an entire week (between Christmas and New year for some places; for the school summer holidays in other areas of the country- it depends on the local traffic pattern highs and lows).

So at one extreme "overnight closures" do not affect any timetabled passenger train services and therefore work can be undertaken disrupting few people, but it takes ages to do the job, is typically very expensive and needs lots and lots of separately designed packages all dependent upon the earlier one and so must be done in sequence- if one fails for any reason, much replanning and redesign.
At the other extreme "extended closure" means days or weeks without a proper (and sometimes any) train service- often called "a big bang". Of course there is some flexibility to "average" in this- if time is lost on one activity there is opportunity to gain some to compensate on another and so the overall programme might be met (whereas if each possession is a separate job then inevitably some will overrun and the railway re-open late sometimes; if the next weekend things go very well then all it means is the engineers get back home to bed sooner but can't "transfer time between shifts". Conversely if doing a big closure and a key person falls sick, the weather is very bad or some other unplanned event happens "all eggs in same basket" and the entire big job may suddenly go extremely wrong and a huge overrun of possession time might occur.

Hence you need to consider the various risks associated with the various approaches- what could go wrong, how likely it is, what the consequences would be. Think of it from the perspective of the designer / installer / tester / maintainer / signaller/ driver/ passenger etc. Think of the direct safety risks of getting confused about what should be undertaken where and when on a multi-staged project- particularly if trains continue to run in the area when the adjacent signalling is being altered. Think of the risks both the staff and the travelling public. Think about the commercial implications of the railway not being available to re-open on time in each scenario.

Hi,

I would like to know more about this topic.

Can anyone please help me out to get more information in the area of Extended closure/overnight and weekend closures.

Thanks

[dorothy.pipet]

Greetings!

Any comments on this, my first attempt at a Mod1 Question?

[PJW]

Greetings!

Any comments on this, my first attempt at a Mod1 Question?

Happy New Year; I think this must be the earliest in a year that anyone has ever submitted an attempt.  We are having the first proper meeting of the Chippenham (mod 2 and one other TBA) group this week but it'll be some while before attempting actual exam paper questions! 
The examiners are still struggling their way through the 2015 papers I believe; I guess they will be trying to get results before the next Council meeting (March) and distributed thereafter, still a fair time to wait- hence I agree that students would be unwise to use them as the trigger to start the wor for 2016!
I'll look at when I get a moment over the next few days but at first glance it looks a good attempt.

[PJW]

Greetings!

Any comments on this, my first attempt at a Mod1 Question?

Happy New Year; I think this must be the earliest in a year that anyone has ever submitted an attempt.  We are having the first proper meeting of the Chippenham (mod 2 and one other TBA) group this week but it'll be some while before attempting actual exam paper questions! 
The examiners are still struggling their way through the 2015 papers I believe; I guess they will be trying to get results before the next Council meeting (March) and distributed thereafter, still a fair time to wait- hence I agree that students would be unwise to use them as the trigger to start the wor for 2016!
I'll look at when I get a moment over the next few days but at first glance it looks a good attempt.

Sorry for the time taken to return to this....

Not a bad answer, but some things I would challenge you on:

1a)
An extended closure potentially permits work to be planned in such a way that the various disciplines actually do not need to work in so close proximity to another- there can be a phased handover of portions of the site from one to another and therefore this may actually reduce the risks than if working in a whole series of short possessions for which it is almost inevitable that everyone would try to be in the same place at the same time; this is the opposite to what your answer implied.  I also think that you should have given an explicit example of the safety risk.

Similarly I would argue that within a long duration extended area closure of the railway that there is more rather than less opportunity to re-plan to recover from problems encountered.  I think the thing to identify is that if there is a COMMON MODE (which could be the weather, or it becomes evident that an assumption previously made is found the hard way not to be valid on the shift) then instead of the effect being relatively limited, there can be a BIG problem which outstrips the ability to recover, because of the "multiplication factor".

To manage a big scale commissioning does need a lot of people and that almost inevitably means more chance of things going astray in mis-communication, many of the people involved will not have the detailed familiarity of the site and the project than  a small core team, plodding through piecemeal week-by-week would have acquired.  
Similarly anything that is "high profile" does nowadays tend to attract the attention of senior managers and that is only right and proper given the commercial and reputational considerations of any overrun; all to often tough when things start going awry their involvement tends to create a major distraction to those whose focus really needs to be on the safe and effective re-planning and negotiation of a fall-back position for minimum commissioning- the more people and the more senior (away from "coal face railway") they are the less effective communication there tends to be than those who are typically dealing with such a situation at 04:00 on the typical Monday morning!

I do agree that reducing the need to perform stagework is a good safety benefit (as well as having other advantages also).

It is not completely clear that repeated stageworks would entail more working close to adjacent open lines, but  I agree that it probably means more likely at begin and end of the possession.  Certainly it would be fair to assume that the percentage of time being worked in the dark and with the pressure of an imminent sign-back time is greater in aggregate for the series of separate stages than one combined long closure and yes overall there would be less work to be done in less overall time so from that viewpoint alone it should be safer as less duration exposed to risk.

Your answer should have explicitly considered SYSTEM SAFETY RISK and PERSONNEL SAFETY RISK- something that it vaguely implied but didn't explicitly state or make very obvious by quoting specific example hazards and risks.  Overall I think you probably considered "other factors" a little too much compared with "safety risk".

1b
A good answer but perhaps you should have mentioned condition survey and correlation as being particularly significant for the multiple stageworks option; needs to happen before most of the design can start.

Also the implications for the series of staged designs when (and it will be when rather than if) some of the earlier ones do not happen as originally intended for whatever reason (lose possession, other department not ready etc.).  When stages are in close succession and there is a need to issue for NR approval and then to the installers to make and the testers to pre-test weeks ahead, the management process needed to recognise that in the interim another stage didn't actually make the change originally intended within the base design for the later work (either didn't happen at all or some need to modify from it's original design.  So version control/ change control should have been explicitly discussed here.

1c
Good.
In such a job, new datalinks to new locs from new central interlocking would be what would really assist; a new TFM is certainly better than opening up an existing plugcoupler on the night to add new input or output but from the scale of the job it is clear that would not want to be mucking around making datalink alterations if it could be avoided.
Any re-use of anything tends on paper to save money but is rarely worth it overall; do need to think carefully where the interfaces between new/ existing will occur.  Clearly there will always be some, but minimising is the key, and where they can't a good means of being able to do some form of "over and back".

Overall pretty good Pass I think; just be careful to focus in this paper upon SAFETY, use terms such as hazard, risk, mitigation, life-cycle.  It is difficult in such a question not to get dragged down into the technical detail, but do try to remain high level and consider how much can be worded to reflect the MANAGEMENT of people and processes