Buoyancy is an upward force exerted by a fluid that opposes the weight of an immersed object. If an umbilical cable is too light it will pull an ROV up, which makes piloting fiendishly difficult when manoeuvring through offshore structures. If the tether is too heavy it will push the ROV down making delicate work impossible. So how do we make sure we get it just right? Find out how we are able to test down to a single gram, up to 200 bar.
When working with cables in shallow water, relatively less of the cable will be submerged while the rest of it is wound on a drum on the vessel. In deep water applications, where relatively more of it is deployed, water provides a cooling effect for the cable when it is subjected to electrical currents. In contrast, in the shallow water applications, layers of cable are spooled on a drum on the vessel and these layers are unable to benefit from the cooling effect. Eventually, the heat caused by the electric current flowing through the cable builds up.
A central component of our cables is a stranded copper wire, which is able to conduct electricity. Around it we extrude a continuous layer of plastic to isolate the copper from its surrounding environment. Twisting this together with other components, forms our custom designed cable.
The plastic has to be a good insulator and thick enough to prevent the copper from shorting to the outside world. Many of our cables operate in deepwater under high pressure, so we need to make sure that our insulation is sturdy enough to keep the water out. Contamination in the plastic will cause the insulation to deteriorate over time and eventually fail.
All change at DeRegt! Following a period of profound organisational transformation for DeRegt, we have now appointed a new managing director. His name is Daniël Ruiter and we had the pleasure of asking him SIX QUESTIONS below. Find out more about our new leader below.
Interview about ROV Challenges with Peter Brussee, ROV Sales Manager, De Regt Cables
Better performance and cutting the cost of deploying work-class ROVs – two key priorities for manufacturers and operators of remotely-operate
d vehicles, both of which DeRegt is addressing with its new cable solutions.