410 March 2007

Mahachai Shipyard Begins Dredger

Having built a reputation for building fishing vessels, Sakchai Rujiprapa of Mahachai Dockyard (Hotips#322) is preparing to build two distinctly different dredgers. A smaller bucket dredge for a private Thai customer will be similar to a design currently operated by the government.

A larger and more complex dredge is in the early stages of construction for an Indonesian mining company. This vessel will be a suction dredge capable of bring ore up from the sea bottom in depths up to 30 meters. The 85x21-meter vessel will be self propelled by a pair of Cummins KTA19 M3 engines rated for 600 HP at 1800 RPM and turning 76-inch propellers through Twin Disc 5170 gears with 7:1 ratios. Two more KTA19 engines, these rated at 500 HP, will power hydraulic pumps, another two KTA19 engines will power water pumps and a single KTA19 runs an electrical generator. In addition to the main propulsion engines three electric-over-hydraulic azimuthing propellers, two aft one foreword, provide fine maneuvering propulsion.

The dredge’s 1.2-meter rotating dredge head, turning at 12 RPM, will feed ore into 16-inch suction pipes with a 1000 HP Cummins KTA38 with 3:1 reduction providing the suction to move ore to the 32 separators. In the separators water and vibration will be used to produce a concentrate that is primarily tin with several other minerals present in lesser amounts. The dredge will be capable of storing up to 2000 tons of concentrate. Onboard accommodation is provided for 25 people.

When delivered the dredge will work off the island of Bangka in north Indonesia.

For more information:

Sakchai Rujiprapa
Director
Mahachai Dockyard Co. Ltd.
200 Tawai Road
Tachalom district,
Samusakorn, Thailand
Phone: 66 (034) 425 359, 66 (034) 425 353
Fax: 66 (034) 425 353

Sathit Suwanprasert
Senior Sales Engineer
Cummins Diethelm Limited
1696 New Petchburi Road
Bangkapi, Huaykhwang
Bangkok 10310
Thailand
Tel: +66 2 652 8510-16 ext. 218
Fax: +66 2 652 7635-36
Mobile: 66 (0)81 913-6599
E-mail: sathit.s@dksh.com
URL: www.dksh.com/thailand

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