F125 Problems

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Posted by Shadow the Cats owner on Tuesday, November 28, 2017 12:12 PM

Cummins knows they have to have an intergrated DPF if they are running SCR even though they are not saying the engine has one on it.  If you read on their website it states an intergrated SCR system we run ISX engines in our fleet and in that same intergrated system is a SCR and DPF in one module. When the DPF regens the SCR also gets extra DEF added to it to prevent added emissions.  It is weird how they intergrated the whole system but it works better than Volvo's or DD or even Paccars.  We have tried all 4 and the ISX is the one doing the best to the point my boss quit ordering Volvo as they refused to put ISX engines anymore in their trucks so we are switching back to KW over a 3 year peroid.  

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Posted by Overmod on Tuesday, November 28, 2017 12:24 PM

The situation in that report is worse than you reported.  907 is one of the two locomotives that entered '1000 mile shakedown' testing Oct 12; there is a "subject matter expert" taking "many train rides to monitor the situation and help develop additional modifications"; and the kicker: NO MORE F125s WILL BE ACCEPTED (they say in California haveanicedayese 'further acceptance is on hold until the issue is resolved' but the actual message is pretty clear, as is that Cat really doesn't know what an answer is going to be right now...

Frankly I'm having a little trouble figuring out what would require "replacing" all the urea tanks.  That indicates the perceived issue is with the pumping and metering end of the SCR, not catalyst poisoning or plugging -- as I recall there were some heat-related issues with tankage mounted over the engine and perhaps 'replace all the tanks' means 'relocate the tanks in the carbody'...

Does anyone know, or can someone find out, who this 'subject-matter expert' is?  Or whether the F125 system retains the sort of combined DOC/self-cleaning "DPF" module that was still in the smaller-engine Tier 4 final ACERT system as late as Cat's promotional material goes.

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Posted by VOLKER LANDWEHR on Tuesday, November 28, 2017 2:06 PM

Shadow the Cats owner
If you read on their website it states an intergrated SCR system we run ISX engines in our fleet and in that same intergrated system is a SCR and DPF in one module.

You talk about a truck engine and there you are right. But as stated before the Tier 4 PM limits for trucks are justone third of the locomotive limits.

Here is a Cummins QSK95 broschure: http://www.marinepartsexpress.com/PDF/QSK95brochure.pdf

On Locomotives (page 11): Cummins own exhaust aftertreatment system is purpose-designed for locomotive installations, using Selective Catalytic Reduction (SCR) technology. This unique, modular system minimizes space claim and improves fuel efficiency, lowering the overall cost of operation. Without exhaust aftertreatment, the QSK95 engine meets Tier 3 locomotive emissions and is ideally suited for locomotives operating anywhere in the world, however tough the conditions.
And on page 20: The QSK95 is ready to meet Tier 4 and other very low emissions standards, using in-cylinder clean combustion to reduce Particulate Matter (PM) emissions and Selective Catalytic Reduction (SCR) aftertreatment to reduce Oxides of Nitrogen (NOx) emissions.
And:
For the most severe low emissions standards, the QSK95 aftertreatment system can incorporate PM-reduction technology, using proven Cummins systems.

EMD and GE were able to avoid DPF on their EGR-only Tier 4 locomotive engines. The EGR reduces the combustion temperature and with it the NOx at the cost of higher PM production compared to SCR locomotives. GE and EMD managed the PMs through in-cylinder measures, e.g. common rail injection.

Cummins has with these in-cylinder measures and higher combustion temperatures less PM than EMD 1010-T4 or GE Gevo-T4.

From my point of view there is no need for a DPF for the QSK95 or C-175-20 on locomotives. If the QSK95 would have to comply with truck Tier 4 PM emissions most likely it would need a DPF.
Regards, Volker

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Posted by VOLKER LANDWEHR on Tuesday, November 28, 2017 2:38 PM

Overmod
That indicates the perceived issue is with the pumping and metering end of the SCR, not catalyst poisoning or plugging -- as I recall there were some heat-related issues with tankage mounted over the engine and perhaps 'replace all the tanks' means 'relocate the tanks in the carbody'...

Here is picture from the presentation I linked on the first page: http://trainweb.org/carl/2017CaliforniaPassengerRailSummit/Slides/Tripoli/IMG_6237.JPG

Indicated are the SCR unit and the dosing cabinet. I think the DEF tank is located directly beneath the dosing cabinet but I'm not sure about it. The DEF tank holds 265 gal.
Regards, Volker

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Posted by Overmod on Tuesday, November 28, 2017 3:05 PM

VOLKER LANDWEHR
For the most severe low emissions standards, the QSK95 aftertreatment system can incorporate PM-reduction technology, using proven Cummins systems.

Having just had to sit through a bunch of arrogant Caterpillar flack videos about ACERT, this line makes me think of one of Shakespeare's characters claiming he could 'call spirits from the vasty deep!'  To which he was then asked "but will they answer?"

I'm sure they're proven ... but what are they, and how do they work? 

Cat was very clever: they explain all about how they actually performed civil disobedience avoiding the dread EGR that lesser companies had to use, but you can just see the little 'third turbocharger' and its flows in the animated 3D video, if you know where to look and are quick.  Much like those PC support scammers who start talking faster and faster the more of a lie they're trying to get across on you.

Problem is that most of what Cat said they were doing in ACERT was almost undeniably good: modulated high-pressure multiple pilot injection, hydraulic adjustable valve timing, staged twins, fast high-bandwidth engine control electronics and good sensors.  What we need is a DETAILED version of that coy little drawing in the California report, with the equipment; I don't think it will be much different from the arrangement I posted for the C175 generators for Daytona... and perhaps we can deduce what the locomotive problems might be from how that arrangement might be packaged in an F125 carbody.

I thought the DEF tank was spec'd for 410 gallons.  Did Metrolink change the size at some point?

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Posted by VOLKER LANDWEHR on Tuesday, November 28, 2017 4:11 PM

Overmod
I thought the DEF tank was spec'd for 410 gallons. Did Metrolink change the size at some point?

I read the of a 410 gal DEF tank in Trains forum thread somewhere but the data sheet on the Progress rail Services website shows 265 gal.
http://s7d2.scene7.com/is/content/Caterpillar/CM20170915-64297-21822

Regards, Volker

Edit: I found the first EMD F125 broschure in the depth of my computer. It contains the 410 gal. DEF tank.

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Posted by VOLKER LANDWEHR on Tuesday, November 28, 2017 5:25 PM

I haven't found any data sheet of the C175-20 Tier 4 locomotive. Even gensets show at max. Tier 2. But I found a C175-16 Tier 4(i) generator: s7d2.scene7.com/is/content/Caterpillar/CM20170823-22107-08927

I didn't find any mention of Acert.
Regards, Volker

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Posted by M636C on Wednesday, November 29, 2017 6:00 PM

Shadow the Cats owner

Cat's first system was call ACERT it was turbocompounding of the exhaust stream. You had part of the exhaust after it had left the main turbo go thru a secondary turbocharger that also was used as the EGR system. It wasn't very reliable or efficient at all. Cat abandoned it 3 years and about 6 billion in research and development cost later. Today you can't give away a truck with acert under its hood. They are that bad. 

 
At the Pacific 2017 Exhibition in Sydney, Australia last month, Caterpillar displayed a marine generator set described as a "C32 ACERT" (in letters at least two feet high). I guess there isn't much demand in trucking for a 1300HP (at 1800rpm) 32 litre engine.
 
Marine generator sets get an easy life, generally, and the biggest problem is that they never run at full power.
 
But the C32 is available for both Tier 4 and Euro IIIb.
 
Peter
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Posted by VOLKER LANDWEHR on Thursday, November 30, 2017 11:58 AM

Caterpillar withdrew from the truck engine sector in 2009 after having problems (and law suits) with EPA 2007 (Tier 4) regulations before EPA 2010 was phased in.

But the Acert technology was still good enough for applications with lower emission standards.

The C32 Acert is EPA Tier 3 marine certified. I didn't find any Tier 4 marine certified C32 Acert engines in the May 2017 Marine Power Solutions broschure.

I did find a Tier 4 marine compliant Caterpillar C32 using exhaust aftertreatment, a clean emission module (CEM) that contains among others SCR but no DPF: http://www.pattencat.com/power/new-power-equipment/marine-power-systems/commercial-propulsion-engines/c32-tier-4-imo-iii

Does it still have Acert?
Regards, Volker

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Posted by Overmod on Thursday, November 30, 2017 7:07 PM

Hard to tell from the pattencat release what the hell in in a Caterpillar large-engine CEM.  I am having to pull up technical material just to find the difference between U-flow and Z-flow CEMs (it is the gas path from the dosing nozzle in one spool to the NOx sensor in the other).

But, without violating the provisions in the CEM installation instructions provided under 40 CFR 1068.261c2, I note that Cat categorically states "Failure to detect proper CEM will result in 100% derated engine performance on all EPA Tier 4 ratings."  This sounds suspiciously like 'complete failure to load' based on what may be complex algorithms against 'cheating' in the engine-control networks or software... producing an effect I think might be entirely like what was experienced at Newhall.

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Posted by VOLKER LANDWEHR on Friday, December 01, 2017 4:09 AM

I took my information for the C32 CEM from Cat FAQs but overlooked that they were for Tier 4 interim.

I found a Caterpillar Application & Installation guide:

s7d2.scene7.com/is/content/Caterpillar/CM20170512-29478-31036

On page 11 is Table I.1-3 Caterpillar Clean Emissions Strategy Table which shows the use of AUS/DEF and SCR for the C32 Acert engine for marine and Petro off shore applications.

Pages 46 and 47 show U-flow and Z-low schematics. U-flow means inlet and outlet are on the same wall, Z-flow means inlet and outlet are offset on opposing walls.
Regards, Volker

Edit: The above mentioned table I.1-3 contains information for the C175 platform for marine applications too. For Tier 4 marine compliance it uses AUS/SCR plus SCR but no DPF.

The Tier 4 emissions standards for locomotive/ marine are:
- NOx: 1.3/ 1.32
- PM:   0.3/ 0.294
- HC:   0.14/ 0.14
All values are given in g/bhp-hr. While locomotive limit values are given by EPA in g/bhp-hr they are given in g/kW-hr for Marine applications. The differences come from converting to g/bhp-hr.

A marine Tier 4 engine would be locomotive Tier 4 compliant. So again, there is no DPF used on the C175-20.

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Posted by Overmod on Saturday, December 02, 2017 8:46 AM

The Cat Tier 4 final tech specs, at least those available 'publicly', are all over the place.  Carefully not discussed is, or appears to be, whether Cat continues to bundle a 'self-regenerating' filter (they have seemingly always tried to avoid calling this a "DPF" whenever they can in discussing ACERT) as the follow-up to the DOC in their pre-module on engines that use DOC.  You can confirm faster than I whether Cat says the Metrolink C175s still employ DOC ahead of the SCR apparatus; I thought I had seen references the oxidation catalyst was still used on some of the larger engines, and it would be useful to know if it were now only a standalone module and not 'integrated' with advanced Cat technology for reducing PM emissions...

The 16-cylinder C175 genset engines have an amusing difference between the "50Hz" and "60Hz" versions: the compression ratios, which are substantially higher on the 50Hz version.  I suspect the 'fluids consumption' on the higher-compression version is higher in DEF but lower in SFC, again with substantially all the NOx abatement being handled chemically rather than by means that nominally increase PM like cooled EGR.  Interestingly this difference does not continue across to the specs for the C175-20 in the same source material.  This might reflect concerns with stresses in the longer 20-cylinder crank, as otherwise use of 'full chemical NOx abatement' would imho favor using the higher compression ratio.

You will note in the document you cited that the CEM discussions and even illustrations go up to units with 20 bricks.  I wonder what engine that unit might be installed on.  I might observe more specifically that CEM on a C175-20 isn't really needed for Tier 2 compliance, so my previous observation that the 'blackstart' facility for the proposed LNG facility has to be Tier 4 compliant (it is designed around 200hr/yr operation which is twice that for the Tier 2 allowance for such gensets) has some more implicit support, and by extension that details of a C175-20 Tier 4 application for gensets will more probably than not share significant IP and construction with the locomotive (and marine) applications.

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Posted by VOLKER LANDWEHR on Saturday, December 02, 2017 3:15 PM

Overmod
You will note in the document you cited that the CEM discussions and even illustrations go up to units with 20 bricks. I wonder what engine that unit might be installed on.

The Application & Installation Guide shows in Table IV.2-1 on page 15 that 16 and 20 bricks are used for the 3500D and C175 engines.

Overmod
Carefully not discussed is, or appears to be, whether Cat continues to bundle a 'self-regenerating' filter (they have seemingly always tried to avoid calling this a "DPF" whenever they can in discussing ACERT) as the follow-up to the DOC in their pre-module on engines that use DOC.

I'm not sure if the current C175 engines are still Acert equipped. The 2012 railway engine ratings guide shows a C175-16 Acert. I haven't found a newer guide. The marine engine railway guides from 2012 to 2017 all show just C175-16. So I don't know what to believe.

The Application & Installation Guide shows in Figure 2-1 on page 14 a CEM system diagram without DPF and without DOC. From a Cat FAQ page: https://www.cat.com/en_US/by-industry/marine/USEPATier4FinalMarineEmissions/tier-4-faq.html?cq_ck=1443800038821.html
Q. For these marine engines, are any other after-treatment devices needed besides the SCR system (ie. diesel particulate filters (DPF), diesel oxidation catalysts (DOC), exhaust scrubbers, etc.)?

A. No. Additional after-treatment such as DPFs and DOCs are not required. The reduction of particulate matter (PM) down to Tier 4 Final levels has been achieved through in-cylinder enhancements which eliminate the need for these additional after-treatment devices.

All above is found in papers on marine applications. But as the emission limit are almost the same as for locomotives the measures won't be different.
Regards, Volker

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Posted by K. P. Harrier on Sunday, December 03, 2017 9:47 AM

An Onsite Review and No F125’s

On the evening of Friday, December 1, 2017 a visit was made to the San Bernardino stop, for probably four hours or so, and NO F125 units were seen.

It is presumed NO F125’s were out and about running in the system, or if they were, their numbers were so few as to be insignificant.

So, the F125 failure recently and the resulting humiliation of the Metrolink boss may be having more of an impact than first thought.

At this person’s first arrival in San Bernardino, the public address system was announcing a certain numbered train was 15 minutes late because of ‘signal issues.’  Whatever the signal problem was, it had a rippling effect, with some arriving trains getting 45 minutes late.

One departed train to Los Angeles returned about 20 minutes later.  Presumably, it met a late train at Rialto or Fontana, switched passengers, and probably crews too, and at least one run was somewhat on time again.  So, the night in question more than F125’s were a troublesome issue.

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Posted by Miningman on Sunday, December 03, 2017 9:57 AM

Superb picture. They have done a nice job at this station. Thanks

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Posted by K. P. Harrier on Sunday, December 10, 2017 10:35 PM

Was by the Keller Yard just south of Cesar Chavez Blvd. in Los Angeles Friday, December 8, 2017, and there were a bunch of  F125’s therein, mostly with very dusty tops.

As usual, there were NO parking spaces anywhere in the vicinity, so no photos could be taken of the dusty group.

The new units known to be being delivered now must be being taken elsewhere.

One of those F125’s now being delivered was known to have made a trip northbound over Tehachapi, apparently misrouted.  A day or two later one, probably the same one, was seen southbound at the southern foot of the Pass.

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Posted by VOLKER LANDWEHR on Tuesday, December 12, 2017 1:10 PM

The minutes of the December 8th, 2017 Board meeting were published:
http://metrolink.granicus.com/AgendaViewer.php?view_id=3&clip_id=413

No word about the reasons of #907's breakdown at its November 18th, 2017 unveiling at Newhall Station.

Regarding the reported urea problems there is the following information. The primary failure mode was a failure to transport the urea to the day tank.

Quote page 370: Two failure modes were observed: failure of "gating solenoids" to open - restricting urea flow from storage tank & "loss of prime" preventing transfer pump from pumping urea fluid from storage tank up to day tank.

And analogous: Since a second modification addressing these failures the units have each run about 700 miles each without additional failures. Staff expects to remove the stop order if recent reliability gains continue.
Regards, Volker

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