PRESS RELEASE
GRAB DREDGER “GOSHO” OWNED BY KOJIMAGUMI CO., LTD. SETS A GUINNESS WORLD
RECORDSTM TITLE FOR THE LARGEST GRAB DREDGER

Grab dredger “GOSHO”, built by Kojimagumi Co., Ltd. (Kojimagumi), in association with
Sumitomo Heavy Industries, Ltd. (Sumitomo), Kawasaki Heavy Industries, Ltd. (Kawasaki)
and Walter Hunger GmbH & Co. KG (Walter Hunger), has officially been recognized as thelargest grab dredger by Guinness World Records Ltd.
Certified title：LARGEST GRAB DREDGER

Certified record ：GRAB BUCKETCAPACITY

200m3（7.062 ft3HEIGHT

8.84m(29ft)

WIDTH

12.92m(42ft 4in)

LENGTH

5.85m(19ft 2in)

1,607 in3）

（Capacity is measured by 3D laser scanner）“GOSHO” has been operating in Singapore since March, 2016. The presentation
ceremony of the certificate is to be held in June, 2017.

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Grab dredger is a work vessel for seabed excavation with the grab bucket. Main task is＊

to deepen and widen the channel. Lately the grab dredger is highly recognized as one of
the excavating methods for the seabed resources.
■ “GOSHO” ‘s COUNTER WEIGHT SYSTEM realized “WORLD LARGEST”“GOSHO” is equipped with Counter Weight System in the dredge to lift the grab bucket.
Conventional grab dredger uses the winch to lift the bucket and the soil directly, and thelimit of the winch’s hoisting capability was the wall in manufacturing the larger grabbucket. Kojimagumi, then, invented the Counter Weight System. The system hoists only
the weight of the soil by the hydraulic cylinder, utilizing the counter weight for lifting,balancing the weight of the grab bucket with the counter weight. With this system,
simpler structure and power saving was achieved and it led to the realization of thelarger grab bucket.
■ Structure of Electric Hydraulic Grab bucket“GOSHO”’s bucket has built-in motor and hydraulic system. It consists of shell part,frame part, hydraulic unit part, cylinder part and hoisting hanger part. How it works
mechanically is that it opens and closes the bucket by providing the cylinder withpressured oil generated by the hydraulic system. Power is supplied by the cable reel.
■ Principal specifications
Grab bucket: Self weight370 ton：Capacity

200m3（Equivalent to 40 of 10ton truck)：Open/Close time

Closing time

26 secOpening time

18 sec：Hoisting rope

φ60mm x 16 ropes：Power supply

Main pump

600V 60Hz

3φ

Aux. Pump

600V 60Hz

3φOperating circuit 220V 60Hz

1φ：Motor

Main pump

132kW x 8

Aux. pump

7.5kW x 2

：Open/Close cylinder

φ580ｘ430ｘ3100 mm x 2：Pump

Rated 350kgf/cm2 Max. 400kgf/cm2 x 8
Flow：Tooth

450L/min10 teeth （ Length 850mm, weight approx.
400kg each)2Grab bucket hoisting cylinder

VesselDredge：Dimension

Ø970x660x19.800 mm：Max. elongation

Approx. 20m：Breadth overall36m：Length overall

100m（Equivalent to 22 valley ball courts）：Height60m（Equivalent to a 20-story building）：Draught

3.6m：Electric hydraulic slewing system：Hoisting load

690 ton：Working radius

31m：Dredging depth

48m：Head above water

10m：Hoisting speed

In the air

0.758m/sec

In the water

1.075m/sec：Lowering speed

0.905m/sec：Turning speed

0.6 times/min：Turning angle±155°：Dredging depth

48m■ Background of the challenge“GOSHO”, built in 2000, has operated in the Middle East and Africa with theInternational dredging company since 2011. In 2014, as preparation for deeper andlarger project, we started the major modification and development for “GOSHO”, which
completed in January, 2016. For the mega size hoisting cylinder, as finding the fact thatno manufacturer was capable for the job in Japan, we placed an order to German cylinder
manufacturer, Walter Hunger. Crane’s structural part was manufactured by Sumitomo.
Hydraulic system, by Kawasaki.

3Taking this major modification and development as our opportunity, we decided tochallenge the Guinness World Records title under their guidelines.

■Kojimagumi’s outline(1) Company name

Kojimagumi Co., Ltd.

(2) Location of head office

1-6 Kiba-cho, Minato-ku, Nagoya, Aichi, Japan(3) RepresentativeTokuaki Kojima(4) Description of businessDredging, reclamation, civil construction work andRepresentative Director, President

related activities(5) Paid-in capital

90 million yen(6) FoundedJune, 1919

(7) Established

December, 1941

※GUINNESS WORLD RECORDSTM is a registered trademark of Guinness World Records
Ltd.

Media inquiries:

Kojimagumi Co., Ltd.
Overseas Business, Business Development Dept.
Phone： +81-(0)52-691-7040

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