High-performance pultrusion for advanced composites

HIPPAC: High-performance pultrusion for advanced composites

Background

The pultrusion process is a cost-effective manufacturing procedure that has been developed to produce composite materials parts with a cross-sectional area consistency. It is a proven manufacturing method for obtaining high-quality Fibre Reinforced Plastic (FRP) profiles with consistently repeatable mechanical properties. During the process, the fibres are impregnated with a resin and are pulled through a heated die where curing reaction takes place. Then, the pultruded part is moved with pullers and the finished profiles are cut to length by a saw at the end of the line.

Objective

HIPPAC aims to improve and facilitate the utilisation of the pultrusion process to develop new advanced composite profiles. The main objectives comprise the development and implementation of advanced digital tools combined with process control and monitoring. The improvements of the pultrusion process and enhancement of spar cap quality with regards to mechanical specifications and weight reduction will be utilised by HIPPAC’s approach. In particular, the following aims were set:

• Develop a digital tool to accelerate pultrusion die design and line set-up
• Implement innovative process monitoring and quality assessment control solutions
• Improve consistency and product quality
• Improve strength
• Reduce cost.

Benefits

Using pultrusion process to manufacture wind turbine (WT) components, such as spar caps can make operations significantly more efficient and can enable the development of much larger WT blades. Wind energy continues to grow in importance, generating 3.5% (960TWh) of the total electricity produced worldwide in 2018 - up from 0.8% in 2008. The UK with 57TWh (17%) of total electricity generated is leading figure in the industry. In 2018, the UK started running the world's largest offshore wind farm the £1 billion Walney wind farm off the coast of Cumbria, which generates enough energy to power 600,000 homes.

There is an apparent need to increase the quality and size of wind turbine blades as the wind energy demand has grown vastly in the last decade. However, it is particularly challenging to maintain the cost and mechanical specifications of the structures when the size of the blades increases. Thus, the main driver is to design robust manufacturing technologies to produce lighter and stronger parts.

Impact

The development and implementation of new advanced digital tools can increase turnaround, reduce wastage, and improve productivity and part properties. These tools will facilitate the accessibility to manufacturers and end-users in order to assess part’s performance more accurately prior to its implementation. In addition, digital tools are important to the UK manufacturing sector that supports digitalisation and aims to increase productivity. HIPPAC will assist offshore wind turbines and projects that are in line with the environmental impact and the UK industrial priorities.

Brunel Composite Centre's Role

HIPPAC’s digital tool will be adaptable to any available part profile in order to enable interactive use during the planning of the process. The geometries of the composite part and die are included in the suggested approach of the simulation problem. In this way, the thermochemical model that requires a description of the geometry and materials will be used to calculate the temperature distribution inside the part. The digital tool will allow the enhancement of part’s quality as the temperature distribution inside the die defines the final properties of the part through the resin cure.

Project Partners

• TWI Ltd https://www.twi-global.com/
• Exel Composites UK https://www.exelcomposites.com/
• ADVISE-DETA Ltd https://www.advise-deta.com/en/
• Brunel University London https://www.brunel.ac.uk/