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PUBLISHED BY THE AMERICAN WELDING SOCIETY TO ADVANCE THE
SCIENCE, TECHNOLOGY, AND APPLICATION OF WELDINGAND ALLIED JOINING
AND CUTTING PROCESSES WORLDWIDE, INCLUDING BRAZING, SOLDERING, AND
THERMAL SPRAYING
March 2012
• Bonus: The American Welder
Marine Construction and Repair
• Do-It Yourself Project
• FABTECH Canada Preview• New Filler Metal Spec
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3WELDING JOURNAL
CONTENTS32 Undertaking a Complex Underwater Repair
A cargo ship filled with iron ore suffered extensive damagefrom
a grounding, but was put back together again by anunderwater repair
teamD. Phillips
40 FABTECH Comes to CanadaThis popular all-inclusive fabricating
and welding exhibitionopens up to a Canadian audience
43 Welded Aluminum on Ships — An OverviewAs shipbuilding
techniques evolved, so did the use of aluminumG. A. Mirgain
48 Build Your Own Campfire GrillThis do-it-yourself project has
everything you need to know toget startedB. Pelky
51 New AWS Spec Details Flux Cored and Metal Cored ElectrodesA
new filler metal classification system addresses the newgeneration
of flux cored and metal cored electrodesD. Crockett
Welding Journal (ISSN 0043-2296) is publishedmonthly by the
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AmericanWelding Society is located at 550 NW LeJeune Rd.,Miami, FL
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is made. Starred (*) items excluded from copyright.
DepartmentsEditorial ............................4Press Time
News ..................6News of the Industry
..............8International Update ............12Stainless Q&A
....................14RWMA Q&A ......................20Point of
View ....................24Product & Print Spotlight
......26Conferences ......................60Coming
Events....................62Certification Schedule
..........64Society News ....................73
Tech Topics ......................74Guide to AWS Services
........84
Personnel ........................88American Welder
Learning Track ..................96Fact
Sheet......................100
Classifieds ......................106Advertiser Index
................108
65-s Continuous Cooling Transformation Behavior in theCGHAZ of
Naval SteelsTransformation diagrams were developed for the
coarse-grainheat-affected zone of HSLA-65, HSLA-100, and HY-100
steelsX. Yue et al.
74-s Developing an Alternative Heat Indexing Equation for FSWA
heat transfer model was developed to help predict the correlation
between weld tool geometry and process parametersJ. A. Querin and
J. A. Schneider
81-s Improving Supermartensitic Stainless Steel Weld Metal
ToughnessExperiments were conducted to achieve weld metal
toughnessimprovements through varying postweld heat treatmentsS.
Zappa et al.
89-s Ultrasonic Wave Assisted GMAWMetal transfer showed
improvement with the application of an auxiliary detaching force Y.
Y. Fan et al.
Features
The American Welder
Welding Research Supplement
32
93
43
March 2012 • Volume 91 • Number 3 AWS Web site www.aws.org
On the cover: A Hydrex senior diver/welder/technician welds a
longitudinal stiffener on the side of the Eleftheria K in October
2011 as part of a major repairafter the ship had grounded off the
Suez Canal. (Photo copyright 2011, Hydrex.)
91 How to Pick the Right-Sized Welding CableA formula is given
to calculate a safe size welding cable, depending on the current
used and distance from the power sourceA. F. Manz
93 Welded Benches for Fun and Fund-RaisingWhimsical garden
benches were designed and fabricated to help raise funds for a
project in GuatemalaH. Woodward
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The Eleftheria K (Fig. 1), a Capesize-class bulk carrier, ran
aground at themouth of the Suez Canal in July2011. European
Navigation, Inc., Piraeus,Greece, operates the ship, which was
builtin Japan in 1985. The Eleftheria K is 297m long overall, 50 m
in the beam, 214,263metric tons DWT (dry weight), with a26.7-m
depth, 19.8-m draught, and a dis-placement of 240,311 tons.
The DamageWhen she ran aground, the Eleftheria
K had on board a full cargo of iron oreconcentrate, totaling
212,297.75 metrictons, which had been loaded at the portsof Odessa
and Yushny in the Ukraine fordischarging at Rizhao and
Qingdao,China. The starboard bilge strake wasgrounded at the level
of double-bottom
ballast tanks (DBBTs) 1, 2, and 3. Thedamage was extensive,
covering about 85m along the hull. The grounding causedsevere
indentation of the bilge strake,opening seven holes and cracks
along thedamaged area resulting in the flooding ofballast tanks 1,
2, and 3 — Fig. 2.
A local diving company in Egypt car-ried out temporary repairs
using doublerplates and putty from the outside and ce-ment boxes on
the inside — Fig. 3. Theship then resumed its voyage to
China.However, one week after sailing fromSuez, the ballast tanks
flooded again anda vertical crack developed on the star-board
vertical side shell plating, on the aftpart of the area damaged by
the ground-ing and just forward of the bulkhead be-tween DBBTs 2
and 3, and cargo holds 3and 4 — Fig. 4.
The approximately 1300-mm-long
crack had an average uneven gap of100–200 mm. Had it propagated
upward,the crack would have caused cargo holds3 and 4 to flood,
which could have beencatastrophic for the vessel and her cargo.
The most difficult part of the under-water repairs was covering
this crack/frac-ture for it to become watertight while atthe same
time maintaining local and lon-gitudinal strength to a level higher
thanthe minimum required by the rules.
Underwater repairs and reinforce-ments had to be carried out at
a depth ofapproximately 19 m with the ballast tankflooded, meaning
equal pressure from in-side and outside. Repair procedures
andwelding quality had to be at maximum inorder to hold firm while
deballasting theballast tank so the shell plate could copewith the
resulting hydrostatic pressurefrom the outside. To effect these
repairs,
A damaged freighter needed repairs tostop a leak, prevent
buckling, and keep
cracks from spreading so the ship couldsail to where she could
unload
([email protected]) is withGroup Communications,Hydrex,
Clearwater, Fla.
Undertaking a ComplexUnderwater Repair
BY DAVID PHILLIPS
Fig. 1 — The Eleftheria Kat sea.
MARCH 201232
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the ship had to be diverted to an anchor-age at Fujairah, United
Arab Emirates.
InspectionS. Georgiou, technical manager of Eu-
ropean Navigation, Inc., called in Hydrex,an international
underwater repair andmaintenance company based in Antwerp,Belgium.
The Hydrex inspection revealeda new vertical crack directly on the
bulk-head between ballast tanks 2 and 3.
Georgiou said he decided to call in Hy-drex for the repairs
because “due to theextent and the severity of the damage, thejob
was considered very difficult; there-fore, we decided a specialized
companysuch as Hydrex, with a successful record,well organized,
safety oriented, and expe-rienced in underwater welding jobs,should
be arranged. Furthermore, anyother option to discharge her cargo
ashoreand/or transfer the cargo to another shipwas impossible due
to the ship’s size, herdeep draft, quantity of cargo on board,
noavailability of suitable port/berth facilitiesfor a vessel of
that size in the area, and noavailability of shore floating
cranes.”
Toon Joos, an experienced seniordiver/welder/technician with
Hydrex, flewto Dubai to conduct a detailed inspectionat Fujairah 20
miles off the coast. His re-port and some of the photos from that
in-spection follow.
“The damage starts approximately onframe number 315 and runs all
the way toframe number 227, a total length of ap-proximately 100 m
with a height on thevertical side of approximately 6 m and awidth
under the flat bottom of approxi-mately 3 m. All the plating is
pushed in-side heavily with several cracks that havebeen repaired
by other diving companiesby means of doublers and epoxy putty.
Un-fortunately, there are still leaks. We can’tdetermine the
locations due to the previ-
Fig. 2 — The ship at anchor near Fujairah, UAE. The ship has a
severe list to starboard due to the leaks and flooding of
theballast tanks.
Fig. 3 — (Top) The buckled hull and the previous attempt at
repairs.Fig. 4 — (Bottom) Close-up showing the severity of the
long, verticalcrack discovered in the hull.
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Fig. 5 — Sketches of the damage andrepair proposal: A —
Transverse viewof the side shell vertical fracture; B —repair
proposal for the vertical fracture.
Fig. 6 — Exterior view of the side shellrepair proposal for the
vertical fracture.
A
B
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ous repairs and because the tanks (num-bers 1, 2, and 3) are
flooded. Betweentanks 2 and 3, I can see there is a crack1300 × 10
mm just in front of the bulk-head. There is a repair done by (local
com-pany), but the shell plating is pushed in-side due to the water
pressure when thetank was pumped out.”
Planning the RepairPart of Joos’s report was a proposal for
repair of the damage. The idea was to makesufficient repairs for
the vessel to sail toChina to unload her freight. Then she couldbe
drydocked and permanent repairs made.The main problem was to
sufficiently rein-force the 1.3-m vertical crack to prevent
thetorsion of the ship while under way fromexpanding it and
breaking the ship, and tomake the hull watertight so that the
ballasttanks could be pumped out. The first stepof the proposal was
to involve a naval ar-chitect so that the various drawings and
cal-culations could be done and approved.
The Naval ArchitectHydrex had recently worked success-
fully with Michalis Chourdakis of C. N.Zachopolous &
Associates Ltd., marinesurveyors and consultant engineers,
Pi-raeus, Greece. The company recom-mended his services to
Georgiou, whowas in charge of the repair operation forEuropean
Navigation. Chourdakis isalso a technical consultant with
TsavlirisSalvage Co., one of the world’s leadingsalvors. In this
case, no salvage opera-tion was required so Tsavliris was not
in-volved, but Chourdakis explained thathis work with Tsavliris has
given him agreat deal of experience with major re-pairs of this
nature.
Chourdakis and his colleague, P.Koutsourakis, a surveyor and
specialistin 3D drawings and presentations, stud-ied the results of
the Hydrex inspectionand the proposed repairs and worked outthe
engineering details. They came upwith a new description of the
damage, a
plan for repairs, calculated the variousstrengths and
thicknesses required, andproduced a set of drawings.
Grounding DamageFollowing is the new damage descrip-
tion and temporary repairs proposal.The damage description is
based on in-
formation received from the Hydrex diveron board at Fujairah on
May 9, 2011.
The report stated in part: “On the sideshell plate starboard
side and in the areaof the double-bottom ballast tank No.
2starboard found a vertical crack of ap-proximate dimensions 1300 ×
10 mm lo-cated between frames No. 228 and 229 andon the first plate
after the bilge plate. Dou-ble-bottom ballast tank No. 2 starboard
isflooded — Fig. 5.
Repairs ProposalThe purpose of the repairs was to ac-
complish the following:
Fig. 7 — Sketches of the sequence(left to right) for fitting the
repair.
35WELDING JOURNAL
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• Stop the crack (avoid propagation).• Reinforce the damaged
area.• Reinstate water tightness of double-
bottom ballast tank No. 2.• Reinstate the continuity of the
dou-
ble-bottom side longitudinals.• Reinforce the cracked side shell
plate
to avoid movement.Following is the repair plan:
• To stop the crack and avoid propaga-tion, drill adequate
crack-arrest holeson the shell plate at both ends of thecrack —
Fig. 6.
• To reinforce the damaged area, fit fourangle bars and weld
them externally onthe shell plate in line with the
existingdouble-bottom tank’s side longitudi-nals covering two web
frame spaces.
• Extend the stiffening longitudinallyfrom frame 225 to frame
231.
• Fit same-size angle bars and weld themvertically and in line
with frames 228
and 229. These would be extended oneside longitudinal up and
down from thecrack’s ends — Fig. 6.
• Form the web of the angle bars to ex-actly fit the hull’s
actual shape.
Three-dimensional fitting sketchesshow how the repair was
planned to goforward — Fig. 7.
Hydrex confirmed that the plan couldbe executed, and European
Navigation ac-cepted the proposals.
All calculations for the local and lon-gitudinal strength of the
vessel were sub-mitted and approved by the vessel’s clas-sification
society, Nippon Kaiji Kyokai(Class NK), and H&M
Underwriters’surveyors. While the work was beingconducted, a Class
NK surveyor was onsite to verify the repairs were carried
outaccording to the approved drawings.
Chourdakis noted that for the jobto be successful, high-quality
welding
and precise premeasurements wererequired.
Making the RepairsHydrex flew two experienced divers/
technicians, Cedric Wyckmans and PhilipMartens, from Antwerp to
Dubai to makepreparations for the job, including secur-ing a
suitable workboat and other neces-sary equipment. A week later,
Joos flewin with a team of four additional
divers/welders/technicians. Work began and con-tinued intensively,
day and night, for thenext 5½ weeks.
The first step was to take measure-ments for the frame that
would be fabri-cated and then welded in place over thelarge
vertical crack. The frame would formthe structure of the cofferdam
that wouldbe used to make the crack watertight andwould also be
used as a frame of reference
Fig. 8 — (Top) Construction of the initialframe on the deck of
the freighter.
Fig. 9 — (Bottom left) The distortedshape of the hull was
carefully measured
in relation to the frame, withmeasurements taken every 5 cm, so
the
plates that would become the structure ofthe box could be
accurately cut to fit.
Fig. 10 — (Bottom right) The plates werelowered down the side of
the ship so theycould be fitted accurately to the damagedhull
before being welded into a watertight
box on deck.
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so that accurate measurements could thenbe made and plates cut
and welded inplace. Hydrex welders working with sub-contractors on
the deck of the EleftheriaK constructed the frame — Fig. 8.
With the frame in place, measurementscould then be taken so that
the sides ofthe cofferdam could be cut to the shapeof the badly
buckled hull and then fitted— Fig. 9. Joos explained, “A good
fittingmakes it much easier to weld. Under thewater, a gap of 1 cm
is a lot harder to weldthan a gap of 3 mm. If you go over 1 or
1.2cm, then you have to build up. So about 1cm is the limit. Some
welders can handlea 1 cm gap. A good fit makes it much eas-ier. If
you have a zero gap, it saves hoursand hours of welding time.” With
the shipout of service until the repairs could becompleted, the old
adage, “time ismoney,” took on a whole new meaning.
The plates were cut on deck, then low-ered and tacked to the
hull so they couldbe adjusted to ensure a close fit beforebeing
welded to the box — Fig. 10.
After the plates were fitted, the 300 ×60 cm box was constructed
on deck —Fig. 11. This was done because surfacewelding is somewhat
faster than under-water welding.
The finished box was then lowered intothe water and welded to
the frame and thehull, inside and out, three passes through-
out — Fig. 12.Once the box was in place, the stiffen-
ers were ready to be welded onto the hullextending fore and aft
from the crackedhull area. The stiffeners were fabricatedon deck,
then lowered into position andtack welded in place. They were then
stripwelded with a 15-cm strip every 15 cm, topand bottom of the
stiffeners — Fig. 13.
The next step was to close the coffer-dam by welding a plate on
top of the boxthat had already been welded to the hulland the
frame. When the cofferdam wassealed, the crack was no longer open
tothe sea — Fig. 14.
Joos recalled the problems encoun-tered when ballast tanks 1, 2,
and 3 weredeballasted — Fig. 15. “When we startedpumping,
unfortunately some cracks
broke. Nobody knew what was inside —how many longitudinals were
still attachedon the inside — so we put additional stiff-eners and
then tried to pump again. Again,we had a few minor cracks. Because
thedepth of the vessel was 24 meters on thebottom, there was a huge
amount of pres-sure forcing inward. The full structureneeded to
resist the pressure. We had afew cracks again so we decided to stop
andput in some additional stiffeners in morelayers to get more
strength on the welds.The third time we started
deballastingeverything went okay. There was no fur-ther leak.”
Georgiou added, “Furthermore, dur-ing the course of repairs —
due to failureof the reinforcements — the original re-pair plan had
to be reviewed twice and
Fig. 11 — (Left) The 300 × 60 cm boxfabricated on deck prior to
being loweredinto the water and welded to the hull.
Fig. 12 — (Right) Close-up showing thebox in position over the
crack.
Fig. 13 — Strip welding the longitudinalstiffeners in place on
the shell plate.
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extra stiffeners had to be fitted.” Thisproved the degree of
difficulty of the job,according to Georgiou.
Finally, just 27 days after work began,the repair was finished
with all stiffenersand brackets in place and welded. Epoxywas
applied to prevent the welds fromrusting — Fig. 16.
Another team worked on the insideafter the crack was made
watertight andthe ballast tanks could be pumped out. Itwas with
this repair fully completed withclassification society approval
that theship was able to sail.
External welding totaled approxi-mately 500 m, an incredible
amount ofwelding for the given timeframe, par-ticularly when one
considers that mostof it was underwater and at consider-able depth.
Shielded metal arc weldingwas used throughout. Two welding
ma-chines worked constantly, and there wasa third on standby as a
backup. Theequipment is basically the same as isused above water
except that a differ-ent electrode, suitable for underwateruse, is
employed.
The underwater external repair was
carried out by seven Hydrex welders work-ing in shifts. The
diving routine consistedof two hours under the water followed bya
21-min decompression stop at 3 m andthen a 4-h interval before
diving again inthe afternoon, following the same routine.The divers
dove once or twice daily fol-lowing the same routine, with two
diversin the water at the same time. All thedivers used nitrox, a
40% oxygen/60% ni-trogen mixture.
At the beginning, the divers worked ata depth of 20 to 21 m.
When the ballasttanks were emptied and the ship came up
Fig. 14 — Closing the cofferdamover the crack.
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straight, recovering from its list, they wereworking at 17
m.
Georgiou, who chose the repair com-pany and the naval
architects, was verysatisfied with the work and the results.“We had
very good cooperation duringthe entire period of repairs,” he said
ofthe teamwork between European Naviga-tion, the naval architect,
and Hydrex. “Therepair was successful, allowing the vesselto sail
to China; therefore, the quality ofthe job was good. The job
completed inabout 27 days, which was very close toquoted time (24
days), but it should beconsidered that additional reinforcementhad
to be carried out, therefore the speedwas also satisfactory.”
ConclusionThe purpose of this repair to the Eleft-
heria K was to stop the leak, prevent buck-ling, and stop the
cracks from spreadingso the ship could sail to where she
coulddischarge her full load and then go to dry-dock for permanent
hull repair. The re-pair was warranted because although the
ship is 27 years old, she has several yearsof service life
ahead.
“The vessel arrived at its port of des-tination for discharging
doing good speeddespite encountering heavy weather andwithout any
damage to the repairs car-ried out or any other damage,”
Chour-dakis said.
Georgiou said, “Upon completion ofunderwater repairs, some
additional re-pairs/reinforcements carried out insidethe ballast
tanks (according to the requestof naval architect) and the vessel
was in-spected by Class. Everything was foundokay and she resumed
her voyage to Chinato discharge her cargo. The ship arrived
in China after about 30 days voyage, with-out any problem or
water ingress in theballast tanks during the voyage, and
dis-charged/delivered all her cargo safely, atthe ports of Rizhao
and Qingdao. Theprovisional repairs carried out by Hydrexat
Khorfakkan anchorage enabled the ves-sel to perform the voyage to
her destina-tion safely.”
The repairs to the Eleftheria K can beconsidered a major
accomplishment in thefield of underwater ship repair and a
tes-timony to the skill and teamwork of theship operator, the naval
architect, and thedivers/technicians who carried it off
suc-cessfully.!
Fig. 15 — A — Additional reinforcement was addedto the repairs
to ensure the welds would hold up
when the ballast tanks were emptied; B — a close-up of the
reinforcement.
Fig. 16 — The finished repair. Thewelds were protected with
epoxy to
prevent corrosion.
A B
Reprinted with permission from WELDING JOURNAL, March 2012. On
the Web at www.aws.org. Permission to reprint in Hydrex Newletter
#186© American Welding Society. All Rights Reserved. Foster
Printing Service: 866-879-9144, www.marketingreprints.com.
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