THE LATEST COUPLING SYSTEMS MAKING AN IMPACT IN THE DREDGING SYSTEMS

Dredge Yard gave an interview for Dockyard Magazine, a monthly publication with regular up to date news feeds and technological developments from maritime industry.

It has always been a demand for state-of-the-art dredging equipment to meet the requirements in the market.
Dredging equipment are influenced by a variety of factors such as the location of the area that needs to be dredged, the placement side of the sediment, type of soil, environmental conditions, safety hazards, lead time, leakage proof systems, etc.
The discharge line in dredging has become the prime focus for engineers to optimize the quality of dredging and reduce overall cost. Improved efficiency of the components used in the discharge line has significantly affected in lowering the cost of a project.
The discharge line depends on the project size and requirements. A survey conducted on the power consumption areas of the dredger shows that the discharge line is taking the biggest part of the used power generated on board.

Factors upon which Power Consumption of the dredgers depends:
? Discharge length
? Bends and height of discharge area
? Type of pipe joints

Power consumption in percentage:
? For Cutter Suction Dredger(CSD) 40% – 70%
? For Trailing Suction Hopper Dredger(TSHD) 30% – 60%

What’s trending in dredging?
The components involved in discharge line are mainly pipe spools and coupling systems.

Dredge Yard is giving an insight into the coupling systems solutions available for discharge line to have better production depending on customers’ needs.

1. Quick coupling Ball joints
There is a range of cost effective, high strength and wear resistant steel ball joints from size DN 400 to 1200 mm. These ball joints are designed and produced by Dredge Yard with latest CAD technologies and years of experience in the dredging field.

Benefits:
? Quick coupling
? High strength
? Easy assembly
? Easy maintenance

2. Ball joints with open liner
To prevent blockage of flow and acceleration of fluid inside the ball joint an addtional liner can be installed in the ball instead of welding the pipe through the ball.
Dredge Yard CFD simulations shows a huge improvements on pressure drop saving up to 50%. Concave liner has one end with the same size as the pipe inner diameter. Other end of the concave liner is bigger than the pipe inner diameter. The diameter of the liner depends on the turning angle of the ball joint.

The benefits are:
? Less pressure drop
? Replaceable liner
? Less wear due to lower speed
? Cost-effective
? Flow friendly
? Eco friendly

3. Bearing Ball Joint
This is a ball joint that is provided with two bearing rings made either from bronze or from duplex steel. This must be done in combination with a duplex ball.

The benefits are:
? No need for use of grease or lubricants
? The ball is more flexible than carbon steel ball joint
? The ball joint has longer life time as duplex is harder than carbon steel
? The liners are replaceable
? Easy dismanteling cause there is no rustweld

4. Spine Hose
A more flow friendly solution is the use of a new introduced spine hose by Dredge Yard that has rubber on the outer side and steel rings (ball and gland) in the inside.

The benefits are:
? Flow friendly resulting in less friction
? Wear resistant inner core
? Lower in weight compare to ball joints
? Easy maintenance by replacing only worn out rings
? Flexible (15 degrees per meter)
? Can’t be folded or collapsed
? Flexible in all directions
? Greaseless
? Environmental friendly