Dredge System Innovations

Category:

Dredge Plant

Production Monitoring

Pumps

Description:

Krupp designs and builds all types of dredges, and dredging equipment. Four primary dredging

innovations were discussed during the visit: the recirculating dragarm system, the dual-bucket

wheel, the flexible spud system for working in higher waves while dredging offshore, and high

efficiency pumps. The recirculating water system takes the overflow from a hopper dredge and

returns it to the draghead. This system reduces turbidity and increases sediment concentration in

the hopper. The system has increased hourly production by 20 percent in South American and

Asian projects.

The dual-bucket wheel allows for efficient cutting for both starboard and port swings of the

cutter. A flap installed at the inflow pipe trains the water to come only from the side the dredge is

cutting.

The flexible spud allows cutterhead suction dredges to operate in larger swells. The spud is set

on a rotating pin and is stabilized with cables to allow more flexibility of the spud. This design

allows more relative motion between the spud and the dredge's hull, thus reducing the stress on

the spud and increasing the working range of the dredge.

Krupp has also developed high-efficiency pumps for dredging operations. The pump's main

innovation is the single unit cast impellers. The impellers are curved to allow for better flow

through the pump, and reduce the overall wear on the impellers. Since the impellers are a single

cost unit, they are not usually repaired but only replaced when worn.

Reviewer:

N. McLellan

Company / Organization(s):

Access Restricted to U.S. Army Corps of Engineers

Projects Completed:

Location:

European, South African, and Asian Projects

Information Sources:

Interviews:

Interviewee:

Dieter Giersch, Eric Ruder

Interviewer:

Neil McLellan, Bob Hopman

Interview Date:

7/24/98

Interview Location:

Lubeck, Germany

Field Investigations: Location:

Lubeck, Germany

Date:

7/24/98

Photos:

Yes

Photo Location:

Hartman Consulting Corporation, Bellevue, WA

Chapter 5 Other Technologies Reviewed