Remote UHP Water Jet Cutting Trial for Damaged Composite Turbine Blade

Location: RGL Research & Development Test Area

Customer: Scottish and Southern Energy

Sector: Renewable Energy

Service: Abrasive Water Jet Cutting

Blade Diameter: 190cm

Blade circumference: 597cm

Blade Wall Thickness: 2.5 - 6.0cm

Blade Material: Fibre Reinforced Polymer

Background

RGL was requested to carry out a trial for cutting a composite turbine blade. The cut is required to release a portion of the blade in the event of a critical failure and snap. In the past, this has been problematic for the industry, with some blades remaining in a dangerous state for a prolonged period. The trial was required to prove the following criteria:

• The operation could be carried out remotely, providing a 100m exclusion zone from the turbine.
• The setup and installation of the cutting apparatus could be executed at elevation using a man basket.
• The rig could accurately cut through a 25-60mm thick fibre reinforced polymer blade that has a circumference of approximately 6 metres.

Method

At our test site, a section of a turbine blade was suspended from scaffolding, and a forklift truck lifted a fenced working platform to simulate operations from an elevated work basket.

A custom bracket was designed and fixed to the turbine blade, enabling straightforward attachment of a chain-driven cutting rig developed specifically for this trial.

An ultra-high-pressure pump (2800 bar) was connected to the cutting rig via 200 metres of hose, alongside a hydraulic power pack to drive the rig around the blade at a fixed speed.

Findings

The trial successfully validated the chain rig’s ability to perform a remote-controlled cut at 100m from the turbine base and 200m from the work face, with installation feasible from a man basket. The ground-level hydraulic power pack configuration proved reliable, and the cut was completed in approximately 26 minutes with high precision.

Equipment:

• UHP pump running at 2800 bar.
• Hydraulic pump to drive the cutting rig.
• Remote-controlled bespoke chain rig and chain guide.