Interface Structure
Once the Bending Restrictor elements have been designed/selected it is necessary to design a suitable steel structure to attach the elements to the adjacent rigid connections.
This often requires complex interface engineering with the pipe/umbilical supplier, subsea equipment designers and installation contractors all wishing to have an input into the design process to ensure ease of construction, installation and integrity in service.
The interface structure comprises a split steel component which has a housing which fits around the 'heel' end of the Bending Restrictor element, and then bolts or clamps to the adjacent structure. This is a 'female' connection and is suitable for applications where the Bending Restrictor is fitted to the pipe at the 'second end-off' the reel.
Alternatively, a 'male' connection can be used where the Bending Restrictor elements fit over the stelework - this is suitable for 'first end-off' applications.
Either the male or female connections can be attached to the adjacent rigid structure by two main methods:
- Reaction flange
- Reaction Collar
The reaction flange has a simple split flange arrangement which bolts directly onto the adjacent structure, whereas the reaction collar is a split shell configuration which clamps around the keys into the pipe end fitting/termination head.
We also have experience of designing and bulding additional adapter flanges, extension spools and pull-in connectors which may be required for particular applications.
All design is conducted in accordance with the relevant codes and specifications (e.g. NORSOK, DNV, API etc.) and fabrication is conducted in accordance with approved weld documentation and fully qualified welders using ASME IX (or equivalent) preocedures.