As the requirement for flexibles and steel catenary risers (SCR) progresses into ever deeper waters, the performance of the clamping systems required to maintain the buoyancy, ballast or tethers in position has changed significantly.
On occasion, flexibles and SCRs also have an insulating layer which in many cases will be subject to creep over the service life of the riser.
The range of variables encountered through the design life of the clamp includes variation in diameter due to changes in internal and external pressures, flexing of the flexible/SCR, allowable clamping pressure, as well as temperature and tension fluctuation.
Whilst the clamps are fitted directly onto the external layers, and this is typically the critical interface for SCR, when dealing with flexibles they are normally required to transfer the clamping load through the outer layers to an internal layer where the lowest COF exists. This radial load transfer is required to prevent slippage caused by in-service and deployment loads with an acceptable safety factor.
Balmoral has designed a unique generation of clamps to ensure optimum performance across varying operating conditions.
API 17L CERTIFICATION
TYPICAL APPLICATION
MODULE COMPONENTS
BENEFITS
API 17L CERTIFICATION
TYPICAL APPLICATION
MODULE COMPONENTS
BENEFITS
API 17L CERTIFICATION
TYPICAL APPLICATION
MODULE COMPONENTS
BENEFITS
API 17L CERTIFICATION
TYPICAL APPLICATION
MODULE COMPONENTS
BENEFITS
This patented product is designed for high clamping load situations to resist the axial movement of large buoyancy and ballast modules.
The high performance clamp is designed to control the contact pressure onto the flowline allowing the accommodation of large diameter expansion/contraction due to its low spring stiffness properties. The clamp is installed directly onto the flexible or SCR using a specialist tool allowing accurate loads to be generated whilst minimising installer fatigue.
Recent developments have adapted this solution to provide increased contact areas between the clamp’s rubber pads and the flexible/SCR. This provides a more even load and distributes the clamping pressure across a larger area.
Typically this means that the opening at the front of the clamp has reduced from 54° to less than 45°, however this is dependent on the design and project specific parameters.
The high performance clamp in summary:
The patented three-piece device is designed to clamp directly onto flexible pipes, umbilicals and SCRs to prevent the module assembly from sliding along the length of the flexible/SCR whilst allowing the module to rotate freely.
This clamp is best suited for umbilical or small diameter flexible pipes where low clamping pressures are required.
The standard clamp in summary:
The integrally clamped module removes the need for a separate clamping system by attaching directly onto flexible flowlines, rigid pipelines, umbilicals and risers.
Custom designed pads placed within the recess of the module accommodate flexible or SCR diameter expansion and contraction while generating consistent clamping loads to resist slippage.
These pads also allow the module to accommodate upper and lower deviations of the nominal outer diameter of the flexible or SCR. Balmoral’s patent protected integral clamped modules and installation methods can be installed using hydraulic cylinders, removing the need for manual bolting of modules and minimising installer fatigue.
The integral clamp in summary:
High capacity integrally clamped buoyancy system with optimised clamping interface
Our latest innovation sees the introduction of a newly patented integrally clamped buoyancy system that provides reduced and evenly distributed line contact stresses at high capacity uplifts.
We believe the new system, Type Approved to API 17L standards, will be used on a minimum of 80% of DBM requirements where a separate clamp solution would traditionally have been specified. The market applicability of ‘INTEGRAL PLUS’ includes flowlines, rigid risers, umbilicals, flexible risers etc. Significant savings will be introduced by a reduction in shipping costs, deck space requirements and product installation times.
Ready to optimise your distributed buoyancy project?
Contact us to find out more | +44 (0)1224 859000
Balmoral Comtec Ltd
A Balmoral Group company
Balmoral Park, Loirston, Aberdeen AB12 3GY | +44 (0)1224 859000 | surety@balmoral.co.uk
Registered number SC301819