Type 45 destroyers face engine refit already.

[Scuffers]

hidetheelephants said:

The story is being very badly reported or the RN are telling fibs in their press release then, as the story is one of replacing the prime movers at refit, something you only do if the engine manufacturers have properly screwed the pooch.

Ah, so as you say, the reporting is ste...

The way iw was written was as a problem with the whole class of ship, not just the individual one...

[FourWheelDrift]

hidetheelephants said:

The story is being very badly reported or the RN are telling fibs in their press release then, as the story is one of replacing the prime movers at refit, something you only do if the engine manufacturers have properly screwed the pooch.

So who's the chief screwer? The design and development by Northrop Grumman Marine Systems, sub-contractors Rolls-Royce for the design of the gas turbine, Honeywell for the design and supply of the intercooler, Ingersoll Rand Energy Systems for the recuperator, or CAE for the Electronic Engine controller?

[hidetheelephants]

Something's very badly wrong, both with the way this is being communicated and with the power system on all 6 ships; it appears from reports that someone fked up the power supply calculations and there isn't enough power to run the hotel loads and drive the ship at the required speed. Quite why it's taken this long to a)decide there's a problem and b)not manage to fix it is pretty embarrassing. Given the whizz-bang nature of the distribution system it *should* be feasible to avoid this nonsense by limiting the power supply to propulsion, but perhaps not given the talk of fitting a 3rd genset; finding space and enough GM for doing this is not a trivial problem.

[V8 Fettler]

FourWheelDrift said:

hidetheelephants said:

The story is being very badly reported or the RN are telling fibs in their press release then, as the story is one of replacing the prime movers at refit, something you only do if the engine manufacturers have properly screwed the pooch.

So who's the chief screwer? The design and development by Northrop Grumman Marine Systems, sub-contractors Rolls-Royce for the design of the gas turbine, Honeywell for the design and supply of the intercooler, Ingersoll Rand Energy Systems for the recuperator, or CAE for the Electronic Engine controller?

Were not BAE the main contractor?

Edit: design and build with BAE as the contractor

http://www.parliament.the-stationery-office.co.uk/...

Edited by V8 Fettler on Friday 29th January 19:02

[FourWheelDrift]

V8 Fettler said:

FourWheelDrift said:

hidetheelephants said:

The story is being very badly reported or the RN are telling fibs in their press release then, as the story is one of replacing the prime movers at refit, something you only do if the engine manufacturers have properly screwed the pooch.

So who's the chief screwer? The design and development by Northrop Grumman Marine Systems, sub-contractors Rolls-Royce for the design of the gas turbine, Honeywell for the design and supply of the intercooler, Ingersoll Rand Energy Systems for the recuperator, or CAE for the Electronic Engine controller?

Were not BAE the main contractor?

From a Crown Copyright MOD document 2003, I suppose subcontractors could have changed but I bet there's a lot of input from different parties all the same.

[Smiler.]

This from that wiki article:

"The freedom to run all propulsion and ship services from a single prime mover for much of the ship's life, thus dramatically reducing engine running hours and emissions."

It may be that a single Gas Turbine is incapable of running everything, the other prime movers being there for maintenance/backup/st-or-bust operations only.

The impact being that the operational efficiencies will not be realised if the other sources are online for everyday use.

Couldn't they just fit a wind turbine

[FiF]

One thing I've heard is that a significant part of the problem has been the decision to replace the desired Paxman diesels with 'off the shelf ' Wärtsilä diesels more suitable for commercial ops. The allegation is that the Wärtsiläs are just not up to the job.

Problem is, with the modular design they were designed to be there for the life of the ship, so they're having to cut routes into the ship to remove and replace. Stern engine room isn't so bad, but the forward engine space is the real problem child.

But then there's other info which suggest both diesels and turbines are to be replaced.

Who knows really.

Edited why does my bloody tablet keep changing Paxman to sodding Paxton? Grrrr
And as for trying to write Wärtsilä

Edited by FiF on Friday 29th January 20:42

[hidetheelephants]

It sounds like an enormous fking mess; at least with T23 there was fair bit of overcapacity in the power generation and 4 units to spread use/wear across.

[Scuffers]

FiF said:

One thing I've heard is that a significant part of the problem has been the decision to replace the desired Paxman diesels with 'off the shelf ' Wärtsilä diesels more suitable for commercial ops. The allegation is that the Wärtsiläs are just not up to the job.

Problem is, with the modular design they were designed to be there for the life of the ship, so they're having to cut routes into the ship to remove and replace. Stern engine room isn't so bad, but the forward engine space is the real problem child.

But then there's other info which suggest both diesels and turbines are to be replaced.

Who knows really.

Edited why does my bloody tablet keep changing Paxman to sodding Paxton? Grrrr
And as for trying to write Wärtsilä

Edited by FiF on Friday 29th January 20:42

I wouldn't go praising Paxman diesels, after all remember what happened to the Paxman diesel engines that run the intercity 125 trains they were highly reliable!

Wärtsilä have a pretty good rep, so is it a casenot poor specification?

[FiF]

Don't know, the problem with the engines as described to me is that the Wärtsiläs are designed for civilian constant moderate output service. However military service demands frequent rapid changes in power output including flat out. The engines aren't helped in this respect by issues with the electrics, alternators, control system etc. That is how it's been described to me by someone who ought to know, but I have no means to check if it's correct. Not sure it's a case of manufacturer A is ace, B is poor.

[Smiler.]

FiF said:

Don't know, the problem with the engines as described to me is that the Wärtsiläs are designed for civilian constant moderate output service. However military service demands frequent rapid changes in power output including flat out. The engines aren't helped in this respect by issues with the electrics, alternators, control system etc. That is how it's been described to me by someone who ought to know, but I have no means to check if it's correct. Not sure it's a case of manufacturer A is ace, B is poor.

Most standby generators are designed to run continously & when correctly specified, harsh conditions (tropical, desert etc).

Unless the power generation & electrical distribution is all designed for constant full load, then the design will take into account a diversity on the load.

If that has been optimistic, the the maximum demand vs connected load will be on the low side.

But that sounds ridiculous, surely an oversight like that would have been established at an early stage. Unless as previously mentioned, kit was constantly added without the necessary design controls.

Of course, this is applying civvy thinking so I could be spouting total bollards.

[hidetheelephants]

Scuffers said:

I wouldn't go praising Paxman diesels, after all remember what happened to the Paxman diesel engines that run the intercity 125 trains they were highly reliable!

Wärtsilä have a pretty good rep, so is it a casenot poor specification?

As far as I can see it's some kind of cooperative effort between Cummins and Wartsila, they don't list the 12V200 on their website any more although I wouldn't read too much into that. The Valenta was as good a high speed diesel as there was back then, any problems there were were attributable to teething trouble(it was a new design in 1975) and they were used as generators in the Type 23 20 years later and were only replaced in the 125 after 2000, some with new Paxmans and some with MTUs. Paxman are part of MAN these days and are not known for making rubbish.

[Taffer]

Looks like someone at the MoD has been quick on the ball and snapped up a couple of second-hand 12v200s and generators already - just 4 more to procure now:

http://www.antoni-intl.com/Equipment+for+Sale/id/4...

[hidetheelephants]

Need 4kV alternators(or BFO transformers), 440V won't cut it on its own.

[davepoth]

It sounds like the GTs are there for the baseload, but aren't too good at ramping up quickly when extra demand is required. That's what the diesels are for.

I guess it's a similar situation to when Eastenders finishes and "everyone" turns their kettle on. If the National Grid don't get extra generation online the frequency drops and consumer equipment stops working properly.

[PRTVR]

davepoth said:

It sounds like the GTs are there for the baseload, but aren't too good at ramping up quickly when extra demand is required. That's what the diesels are for.

I guess it's a similar situation to when Eastenders finishes and "everyone" turns their kettle on. If the National Grid don't get extra generation online the frequency drops and consumer equipment stops working properly.

Maybe,I was watching American public broadcasting channel on satellite the other day, they were doing a piece on the HMS Daring, it was on exercise, as it manoeuvred for a incoming drone the weapons system went down,you would hope critical systems would be on ups, but who knows, maybe the weapons system is to large to have one.

Sky news have just done a piece on the problem.

[Scuffers]

hidetheelephants said:

Scuffers said:

I wouldn't go praising Paxman diesels, after all remember what happened to the Paxman diesel engines that run the intercity 125 trains they were highly reliable!

Wärtsilä have a pretty good rep, so is it a case of poor specification?

As far as I can see it's some kind of cooperative effort between Cummins and Wartsila, they don't list the 12V200 on their website any more although I wouldn't read too much into that. The Valenta was as good a high speed diesel as there was back then, any problems there were were attributable to teething trouble(it was a new design in 1975) and they were used as generators in the Type 23 20 years later and were only replaced in the 125 after 2000, some with new Paxmans and some with MTUs. Paxman are part of MAN these days and are not known for making rubbish.

the 125 problem was basically due to poor spec work, the engines were never designed for the duty cycle they were subjected to, GEC had to pay huge compensation and if I remeber right, the 'solution' was to have more trainsets to reduce the workload and they were also de-rated.

[98elise]

FiF said:

Don't know, the problem with the engines as described to me is that the Wärtsiläs are designed for civilian constant moderate output service. However military service demands frequent rapid changes in power output including flat out. The engines aren't helped in this respect by issues with the electrics, alternators, control system etc. That is how it's been described to me by someone who ought to know, but I have no means to check if it's correct. Not sure it's a case of manufacturer A is ace, B is poor.

I'd be surprised if the power output was rapidly changing on a warship. Pretty much everything is running 24hrs per day.

[FiF]

98elise said:

FiF said:

Don't know, the problem with the engines as described to me is that the Wärtsiläs are designed for civilian constant moderate output service. However military service demands frequent rapid changes in power output including flat out. The engines aren't helped in this respect by issues with the electrics, alternators, control system etc. That is how it's been described to me by someone who ought to know, but I have no means to check if it's correct. Not sure it's a case of manufacturer A is ace, B is poor.

I'd be surprised if the power output was rapidly changing on a warship. Pretty much everything is running 24hrs per day.

Hotel load possibly, but significant differences in setup for type 23 and 45. Can imagine significant varying loads on type 45 DGs.

[Smiler.]

FiF said:

Interesting, thanks. Where is this from?

It is the case that the propulsions system is N+N & that a single GT is supposed to be able of delivering all the load?

I would also assume that a more in depth schematic would show redundant paths.