ROV-operated Friction Clamp
Butler Solutions have a long track record in design and production of friction clamps for the offshore industry. The clamps are being used both top-side and subsea. Our latest delivery is a friction clamp being operated by an ROV. The design is made to make it easy to operate, lightweight but yet robust.
The purpose of the clamp was to support and secure a bend stiffener (avstiver) at Asgard A FPSO, a vessel operating in the North Sea.
Bend stiffeners are used to support flexible pipe, umbilicals and cables when connected to rigid structures or a floating production system where there is a requirement to control the minimum bend rad. A bend stiffener is heavy, so the clamp must be able to apply a very strong grip.
Since the clamp had to be transported in a subsea basket and handled by an ROV, it had to be light to ease the operation by the ROV. We found that the best solution in this case was to use buoyance elements. Hence, the weight was reduced from 305/267 kg dry weight to 30/13 kg in water.
Another issue was the operation of the clamp. Since it was to be operated by an ROV it had to be with as few interactions with ROV as possible. The clamp is therefore hydraulically operated with belonging mechanics to ease the operation. Only one single point is connected to the tool and it is ready for operation by the ROV pilot who will have an easy technical procedure to follow.
User benefits:
- Leight weight in water
- Easy operated by one hot stab
- Mirrored interface, the clamp can be used upside-down
The movie shows briefly how we designed and tested the ROV hang off friction clamp.
You can see the full film here: https://youtu.be/B6e6zJPB224
