ARE YOU SEEKING SURETY IN BEND RESTRICTOR DESIGN, MANUFACTURE AND DELIVERY?

Bend restrictors prevent over-bending at the interface between flexible flowlines/umbilicals/cables and rigid structures by mechanically locking up.

They are normally used in static applications but, unlike bend stiffeners, only provide protection once the pipe has achieved the desired bend radius between the flexible line and rigid structures such as wellhead connections, J-tube exits, rigid pipe crossovers and PLET connections.

Accredited by Bureau Veritas to API 17L standards and tailored to meet or exceed customer requirements across the oil & gas, renewable energy and defence industries, Balmoral bend restrictors provide cost effective solutions through optimised design methods, an ongoing development programme and the use of multiple rigid PU grades.

They are supplied as two-piece units that are bolted together.

Balmoral’s bend restrictor solutions are designed and manufactured in-house using state of the art design software. Key information required for this process includes:

• Flexible pipe OD
• Minimum bend radius
• Service life
• Length of coverage by angle or length
• Support structure details
• Flexible pipe min and max internal temperatures; operation and installation
• Flexible pipe min and max thermal conductivity value if pipe is heated
• Min and max installation air temperature
• Min and max seawater operation temperature
• Installation and operation shear force
• Installation and operation bending moment
• Flexible pipe stiffness if not taken into consideration in the bending moment and shear force loads

Balmoral’s vision is to be a solutions provider and, in most cases, provides a bespoke product tailored to meet specific or environmental conditions. It is understood, however, that clients can seek off the shelf options offering the same quality and surety that a bespoke product typically provides.

Through an extensive investment and research and development project Balmoral analysed its extensive track record and developed a range of standard bend restrictors to cover a multitude of diameters operating to specific temperatures, loading capacity and MBR.

This programme resulted in Balmoral’s standardised bend restrictor range which offers:

• A rethink of the load transfer mechanism to a ‘Box to Box’ system
• Standard mouldings catering to a wide range of diameters
• Improved lead-times on documentation and products
• Tested to capacities with the potential to reduce qualification and expense on individual project testing
• Potential cost reduction over bespoke designs subject to performance requirements, specification and quantities
• API 17L Type Approved design methodology

Balmoral extended its bend restrictor range to include a genuinely boltless restrictor (patent pending).

This innovation allows fitting times to be slashed, offering huge savings in offshore installation costs. In line with Balmoral’s acknowledged track record for product improvement, value has been added by taking something away.

Some existing products claim to be boltless but, in reality, none of them actually are. Balmoral’s boltless restrictor retains industry-leading performance while offering significantly reduced installation times and costs.

Boltless bend restrictor benefits

• Rapid installation time creating significant offshore savings
• Revolutionary boltless interlocking method fully utilising the material’s strength
• Superior load capacity for long and short term conditions
• Excellent temperature resistance, specifically important to long term creep performance
• Significant multiple unit cost efficiency savings
• Minimises sub-supplier risk
• Materials and design methodology API 17L 1&2 compliant

Features

• Interlocking male and female mouldings
• Innovative interlock system (patent pending) removes the need for fasteners
• Bend restrictor lockout prevents cable/pipe over bending
• Proprietary design and testing delivers long service life in extreme environments
• Material fully API 17L 1&2 certified
• Material is mercury and MbAOC free (REACH compliant)

Design specification

• Typical cable/pipe diameters: 20-450mm
• Typical bending moments: 2-120kNm
• Standard minimum bend radius: 1-8m
• Materials: Balmoral marine polyurethane
• Design life: 35 years (or specific project requirement)

These are indicative values as bespoke designs outwith these parameters can be achieved. Please contact Balmoral for more information.

Forged reaction flange

Using this method, Balmoral restrictors couple to the structure by means of a flanged (male) end fitting.

Forged reaction flanges are manufactured using compliant material as a single body which is machine finished and requires no welding. They are coated with a standard marine grade paint system (NORSOK System 7B) and supplied as split units that are bolted together using B7M bolts.

It is not standard practice for Balmoral to supply the bolts used to connect the reaction flange to the end fitting but this can be arranged if required.

PU reaction collar

Using this method, bend restrictors couple to the structure by means of a PU fitting connected to a steel flange located within the groove of the end fitting. Steel flanges are supplied in two halves with a pitch circle diameter (PCD) to match the PU end fitting. All above options can be supplied in Balmoral’s standard welded assembly format.

PU reaction flange

PU reaction flanges are the connecting point between PU bend restrictors and the subsea termination interface and are designed to match clients’ end fittings.

The PU reaction flange design is based on the bend restrictor as both components share neck and pin geometry and utilise the same material.

Benefits of PU interface options include

• Part of Balmoral’s API 17L approval
• Minimising weight above and below the surface
• Eliminating arduous weld specs and procedures
• Minimises need for CP systems
• In-house control from design to delivery
• Solutions designed to match client interface requirements