Tuesday, January 26, 2010

Licking sandy lube


We have left the Tiffany Navy poster child alone for much of the last year - so let's get an update from our buddy at DefenseNews, Christopher Cavas,
A fresh set of problems with the long-troubled LPD 17 San Antonio-class amphibious ships has sidelined two of the vessels, led the U.S. Navy and its largest shipbuilder into a passionate game of finger-pointing, and raised questions about Northrop Grumman's ability to deliver quality work and the Navy's ability to carry out proper shipyard oversight.

The larger issues are coming from two core problems discovered aboard the LPD 17s, five of which are in service with four still to come.

Of more immediate importance is a problem that, left untreated, could wreck the four large diesel engines that drive the ships. The problem is not new but, having once thought a solution was at hand, the Navy and Northrop are once again trying to figure out why a fix hasn't been found.

Another issue, affecting all the ships in the class and other ships built at Northrop's Gulf Coast shipyards, could - unless it's fixed - shorten the service lives of all the ships. But how and why that problem arose could drive closer to the competence of Northrop and the Navy's inspectors to properly inspect weld work.

Engineers are trying to figure out how debris - "contaminants" in engineer-speak - is getting into lube oil in the large diesel engines that drive the ships. The contaminants cause excessive wear on bearings that support a crankshaft at the bottom of each engine. If the problem isn't treated, the crankshaft will be thrown out of line and the engine could suffer serious damage or even be wrecked.

The problem isn't new, the Navy said, and showed up about a year ago in the third and fourth ships of the class.

"We thought we had it licked," Jay Stefany, the Navy's program manager for the LPD 17 program, told reporters Jan. 21. "And that's where we were until right before Christmas."
Oh goodness.

Let's get geeky.
That's when the newest ship in the class, the USS New York (LPD 21), reported a bent crankshaft in one of the four diesel engines that drive the ship. Engineers found that the shaft was thrown out of alignment by scratches being made in the inner ring of the nine bearings that support the shaft - scratches that caused enough of a difference in the thickness of the bearings to make the shaft wobble.

The scratches are caused by particles too small to see - much of them between 20 and 40 microns wide, or about .00118 of an inch, according to Stefany.
The good new here is that CFFC is taking this seriously.
Early in December, Adm. John Harvey, commander of Fleet Forces Command, ordered Rear Adm. Michelle Howard, commander of Expeditionary Strike Group Two, to begin a Manual of the Judge Advocate General investigation, or JAGMAN, of the problem. The effort reportedly is being led by NAVSEA's Rear Adm. Tom Eccles, the Navy's chief engineer. The investigation is focused primarily on the San Antonio and not the New York, which has yet to transfer to fleet operational control.
Make sure and listen to Midrats on Sunday for a BIW funny - but this just adds to the joy of the folks from BIW.

Byron, step to the microphone,
please,
"We found a higher-than-expected failure rate on quality of the thickness of the welds," Stefany said. The issue was not that, properly hangared, the welds would soon fail in service. Rather, Stefany said, the welds are "critical for shock survivability and for service life. You need [the thicker weld] dimensions to guarantee that." As a result, he said, a ship designed for a service life of 40 years might only make it to 30.

"It's not as catastrophic [as the lube oil problem] but we're working it," Stefany said. "It's not as in-your-face as the engines are - basically it's just putting more welding material on."
Note to our friends in Millington. I will help you find the BA/NMP for LCDR/CDR/CAPT types for you to recode and increase your number of inspectors. I will even help you find additional funding for graduate school engineering education - just give me the top cover and the mandate.

If you don't want to contract me to do it - drop me a line and I will find a EDO CAPT that will do it gratis.

Give NAVSEA and SUPSHIPS more qualified personnel with the right mandate and they will help fix this. All you need to do is set the right priority.

Clean lube oil is about as fundamental an issue as you can get. All the "
Best Places to Work" awards in the world don't mean squat if you can't even get grit out of your lube and measure your welds right.
UPDATE: I got a heads-up by One Who Would Know to clarify something in the article,
.... Chris Cavas, got Jay wrong on the "bent crankshaft". It is out of round, not "bent".
Not the same, but important. Have an engineer tell you the difference - your eyes may glaze over - but he will be giddy as schoolgirl telling you about it. You'll make him happy. Kind of like asking Byron about welds ....

There is a larger backstory on what is being done to fix the lube issue. Good people doing hard work....they just need the resources to do it right.
UPDATE: More goodies being slipped under the door on welds.
DDGs have a similar challenge, and it happened because the entire QA cadre dropped the ball. Uncertified and barely certified personnel performed weld inspections on P1 and P2 piping. A good QA will catch the problems and fix them as you build the ship. It didn't happen that way in this case.
Bad welds accumulated over time until the ships were nearly completed, then everyone went "Oops!" The challenge is that the problem was of unknown magnitude because it involved piping that was lagged and obstructed from view in many cases. LPD-17 class had significantly more welds, so more problem welds which meant they got most of the attention.
A Technical Review Team inspection plan was set in motion last year and the push to find a work around has been going on for a few months. Weld repairs are being made. ASTM weld criteria is being accepted where it makes sense and MIL SPEC criteria will be required where needed (it involves a short equation using the lengths of the two weld legs). There is a detailed Risk Analysis out for review at the moment.