ISO8217-2005 Fuel Specs

[TxMarEng]

What do other marine engineers feel about the current ISO8217-2005 fuel specs? Do you think it is time for a revision? Cut limits for cat fines to 50-60ppm? Develop and implement a sound and reliable method for testing sediments and fuel stability to replace the present TSP, TSE, TSA methods? Has anyone experienced problematic fuel with excessive sludging or cat fines that called for repetitive manual cleaning of centrifuges and or automatic back flushing filters?

[The Dieselduck]

I am not entirely up to date on the topic, of late I have only been working with diesel, so my HFO Mental muscles is a bit rusty, but certainly did have lots of issues with fuel out of Galveston (was there for 2 years). For the most part it was okay, I was in charge of the separators for about a year, which was nice to be because I could track performance and see what worked or not. For the most part, we did some minor adjustment in timing and workings to the separators, but overall we were happy with the system, sludge, lots and ugly, but really not unmanageable. Our plant was about 70,000 hp, and we landed about 12 cubic meters of sludge a week (comprising of more than just separator sludge - but mostly from the separators).

The auto filters on the other hand, Bolls type, were a disaster. Once a month, maybe more, we would get a batch of fuel that was just fine according to the fuel reports. But I could tell right away, we were using this fuel because the fuel prep unit would start acting up. Never did find the answer, caused me much headaches. I got use to dealing with it and tweaking temp and pressures myself to make the viscochief happy and smooth the operation out a bit. I figure it was chemicals or waste blended into the fuel, but the fuel reports would never pick it up.

I figured that, because on another ship, we picked up fuel in LA, same thing, reports were good, but a month later, the O Rings started to fail on all the fuel pumps. All 48 fuel pumps were pulled out of service and rebuilt because of this. For 3 months or so the First Engineer and the day crew became very well verse in the procedure of swapping fuel pumps.

Having highlighted these experiences, it would appear to me that even with good practices and standards we already had, the fuel we got was still troublesome. Its nice to have more defined standards, but really we need to be able to have better testing for other things that cat fines and the likes.

Cheers,

[conrod]

Like Martin, I work with MGO, which for the most part is top of the line. However DnV have highlighted some locations where even the MGO is getting bad. Do not take bunkers in the states around central West African Coast..............not that anybody would intentionally go to Nigeria for bunkers.

Unfortunately it is invariablly to late to do anything about it. On an OSV that only carries 1000 cum, you usually start to burn the new stuff within a day or so, and if the pumps and injectors start to fall down, then you go off hire, which is too late to complain about the fuel......and the office is breathing down your neck because not only are you loosing $20,000 a day, but spending the same in new bits.........I agree something should be done about fuel quality, but at source. As we move into a greener, cleaner environmentally friendly fuel era - keep that sulphur low - perhaps somebody, should provide some sort of control over what is ultimately provided to us.............[b]before we load it !![/b]

[TxMarEng]

Over time Boll filters develop a fine sheen or carbonaceous deposit on the candles "gills" or segments. Most often cleaned with Gas Oil this does not remove this film and over time they become more likely to accumulate deposits of cat fines or other sediments. In such case, often the use of an approved safety solvent such as Diskclean with mild air agitation may do the trick and return them to serviceable condition. If this does not work they are easily restored by ultrasonic cleaning. Bool makes a unit and others are available from other sources. They are also excellent for cleaning any fuel injection parts during service. OF course neither method works if one of the greasers has carried out on the candles with a brush or scraper :evil: DNVPS has a TechTip they circulate regarding Boll filters and they are always available to offer tech tips when needed.

[priguy]

It would seem that as the price of crude oil rises in today's markets, one fact becomes ever more apparent. The focus to use less than desirable mid distallate cutter stocks in blending is becoming the norm. As the price and profit for mid distallates rises out of control, HFO blenders are realizing that the cost to use a quality blending agent isn't cost effective. Thus, HFO users are paying the price!

As for ISO 8217, serious revisions are in order. As most in these postings mentioned, they took fuel on and shortly there after began experiencing problems. I'm sure the TSP numbers looked just fine at bunkering and in the subsequent analysis. But the problem lies in the specs. Testing is available and these issues can be caught ahead of time.

One question looms...how to solve fuel quality issues? What has been your experience with fuel treatments?

[TxMarEng]

The proliferation of new engine licensees has resulted in some shortcomings in regards to quality of materials and workmanship as they scurry to source materials. There have been instances of problems with O-rings in which the fuel was suspect however, further investigatioan showed that the material was not up to specification. There was an interesting article last week from a noted Brit engineer quoating the "Inhumanity to engines" from both the inadequacies of new engine builders and the flood of new engineers at sea. Have to agree with his theory.