Potential application

Potential application

This technology would be useful to private industry as well as the Corps

and could result in cost savings of millions of dollars. Currently, the

Corps is planning to convert the dredge MCFARLAND to state-of-the-art de-

sign with respect to dredging technology under the Repair, Alteration and

Modernization Program (RAMP). The Corps recognizes that the recircula-

tion system retrofit has definite merit.

Cost

The exact cost for retrofitting the McFarland with a recirculation system

is undetermined as yet but the benefits are tremendous. The retrofit

could entail replacing hull connections, trunnions, dragarms, davits, and

winches as well as providing additional pumping capacity. A rough esti-

mate for the cost of the retrofits is $2 million.

Company/Organization(s): Access restricted to U.S. Army Corps of

DOP Submersible Dredge Pumps

Background

De Groot Nijkerk of Nijerk, Holland, has successfully developed a se-

ries of submersible dredge pumps called DOP pumps. The DOP pump has

many advantages: it is compact, easy to use, and very suitable for re-

stricted working areas; it is capable of very accurate dredging; has a large

production capacity due to high mixture concentration; has virtually un-

limited suction depth; is easily transportable; and easy to attach to an ex-

cavator, crane, or mudcat.

Technology

The DOP pump is based on existing and well-proven dredge pump de-

sign. However, by applying a mechanical seal as shaft sealing instead of

the conventional gland, gland water and grease are superfluous. The bene-

fits of the DOP pump include: simpler maintenance, greater deployability,

and, due to the lack of extra piping, greater reliability. The impeller is

clamped to the pump shaft by means of a tension set. The DOP pump is

driven by a hydraulic or electric motor placed directly on the pump. The

DOP can be outfitted with various suction mouths such as a cutter unit, jet

water ring, dustpan, or auger.

Chapter 4

Detailed Evaluations