Thermoplastic composite pipe made of ambliFibre system

As part of the ambliFibre multinational research project, a new thermoplastic composite tape winding system was developed. The system has a variety of functions to improve quality and reliability in the manufacture of safety-critical structures, such as composite armor for unbonded flexible pipes.

The AmbliFibre prototype system uses new technologies developed during the project

A hybrid unbonded flexible tube of integrated reinforcing layer made of a thermoplastic composite is a key technology for efficient recovery and transport of hydrocarbons at water depths in excess of 1500 meters. Load, pressure and chemical resistance requirements limit the use of traditional riser systems in these water depths. Considering the increase in the distance between the floating platform and the subsea components, self-weight becomes a problem of a high safety critical component. In the case of unbonded flexible tubes, the use of thermoplastic composites in place of metal layers such as pressure armor significantly increases the self-weight that can be supported due to the high strength to weight ratio of these materials. Further properties, such as corrosion resistance,

Automated production technology
The tape wrapping process, also known as filament winding, automatically and efficiently produces consolidated composite parts made of thermoplastic unidirectional fiber reinforced plastic (FRP) tape in a single molding process without the need for an additional curing step. This eliminates the high investment associated with autoclaves, which appears to be impractical in the continuous production of structures of several kilometers in length. Another advantage of thermoplastic tape winding is that the process is environmentally friendly and has no emissions properties compared to competitive thermoset technology. Using thermoplastic system technology, the tape is fed into the nip where they are subjected to pressure and heat so that it can be completely consolidated with the previous layer in any load-optimized layup. Lasers are often used as heat sources because of their high energy concentration, short response times and excellent controllability.

Thermoplastic composite pipe automated production process

Despite significant developments and major breakthroughs in industrial system technology, laser-assisted tape winding requires a thorough understanding of the reliable production process for safety-critical components. The various control variables that interact with unpredictable process disturbances (such as insufficient tape quality) mean that significant effort is required to achieve a reliable process when changing product design or application materials.

This is a key point in the manufacture of offshore riser systems, as quality assurance and process repeatability are important in view of the serious consequences of field failures.

In the ambliFibre project, a multinational European consortium of industrial companies and research institutes collaborated to strengthen the laser-assisted tape winding process to meet the expectations and requirements of the offshore industry and other industrial sectors. The three-year project ended in 2018 with the task of developing the first on-line model, quality-controlled tape winding process designed to increase flexibility, reliability and productivity. To this end, several new hardware and software modules were developed, tested and validated.

How to make:
The ambliFibre system combines thermal and optical models embedded in overall process control with novel data mining, laser and quality monitoring technologies. This approach can significantly reduce waste while predicting potential failures, thereby reducing machine downtime. The green focus of the technology is supported by an overall life cycle analysis of the resulting product. In summary, the new system represents a major breakthrough in the continuous and discontinuous production of tubular composite parts, such as gas cylinders for automotive applications or composite ultra-deep water risers.

Simulation and adaptive manufacturing

In order to widely use laser-assisted tape windings in the industry, proven global and local simulation and modeling tools are required.

In ambliFibre, this was solved by designing a complex simulation tool at the University of Twente that combines an optical model and a thermal model for determining the laser illumination distribution, which derives the process area based on the output of the optical model. Temperature distribution in . In optical models, ray tracing methods are employed and reflections on the strip and substrate surfaces are considered for optimum accuracy. Thermal simulation is performed locally to achieve temperature distribution in the nip point region and to consider heat development in the thickness direction globally. In the simulation development process, the phenomenon of roller deformation, overlap of the spiral lamination and polymer crystallization was considered.

Given the geometry, materials, process parameters and thermal history, the prediction of the ideal temperature profile opens up the possibility that model-based control can influence the outcome of the process in real time. In addition, the concept of model predictive control was developed and validated in the Fraunhofer IPT.

Martin Schäkel, project coordinator of the AmbliFibre project from the Fraunhofer Institute for Production Technology (IPT) in Germany, explained:

“Customers can come to our factory in Aachen to see if this process is working. From the range of new solutions developed by multinational alliances, they can precisely choose which technologies can meet their specific needs, such as data mining or laser optics. Application. As a research institution, we certainly hope to continue to optimize and improve our technology with our partners.”

“The automotive industry has extensive experience in using traditional materials such as steel and has established good relationships with suppliers over the years. Therefore, we must first address their need for efficient mass production and demonstrate this in a transparent manner. To overcome the suspicions in the industry.”

“Encouragement of industry interest through public workshops with industry stakeholders and our prototype mechanical display in Aachen. We now want to adapt this technology to new parts and applications and see what their potential is.”

This opens up the possibility of compensating for process inconsistencies and disturbances by pre-adjusting process parameters such as laser power in several time steps.

In order to close the control loop, two modules for efficient temperature control and measurement are created. In order to introduce adaptive laser illumination into the process, RWTH TOS and Ixun Lasertechnik have developed a new laser optics system that shapes the gradient of the laser spot.

In this way, the tape or substrate can be heated with increased laser intensity.

The resulting temperature profile was recorded and processed by a high speed thermal imager developed by New Infrared Technologies. The rugged and compact design is easily integrated into the tape winding system. The processed temperature data is analyzed by an algorithm to extract target input values ​​for simulation and process control.

Knowledge-based data mining

To further ensure process quality, data mining algorithms were developed and embedded into the intelligent human machine interface (HMI) of the video system. A relational database structure was created to process and analyze the data generated during the project in a system winding experiment using different materials and process parameters. During these tests using the Fraunhofer IPT winding system, parameters such as process temperature and consolidation force were recorded and the mechanical test results of the samples were supplemented. The data mining engine studies the correlation and direct impact between the process data and the mechanical test results, and draws conclusions about the direct connection between the data in the process and the expected results. In this way,

An intelligent machine interface based on data mining algorithms provides operators with some feedback on the process system.

Data mining engines and simulation models offer the potential to significantly reduce the acceleration time and commissioning associated with fiber reinforced plastics processing when introducing new product designs, new windings or new materials.

In the production process of several kilometers of processing tape, new tools can achieve quality assurance in terms of changing process conditions and interference.

Online monitoring of quality control
For direct feedback on process stability, the ambliFibre project also provides an online monitoring device for continuous measurement of consolidation quality. In order to generate a standardized structure in the tape suitable for process evaluation, the FRP tape was modified during the hot embossing process of the RWTH KEmikro automation. After the tape is welded to the underlying layers, the embossing is utilized to detect the level of consolidation by evaluating their characteristics. The Fraunhofer ILT uses thermal imaging technology to detect embossing directly after the nip point.

An inline monitoring device that detects the degree of consolidation in the tape. After soldering the tape together.

The machine learning algorithm is trained during multiple test trials to reliably detect features and assess the degree of consolidation. Similar to data mining engines, it can process new learning data and provide accurate feedback for new materials, process conditions or winding stacks.

Inline monitoring devices enable real-time feedback on defects that may be caused by insufficient or inaccurate process settings. Through the HMI, the current quality is fed back to the operator, who can adjust or stop the process based on the degree of deviation from the ideal process conditions.

Modular system for industrial production
All new modules were tested and verified in the laser-assisted tape winding system of Fraunhofer IPT. To this end, the pipeline demonstrators are based on General Electric Baker Hughes. As an additional application, a composite pressure vessel was produced and subsequently tested by HBN-Teknik A / S. The results show that the system technology used has good performance and the technology is continuously optimized until the end of the project.
The ambliFibre production system includes all developed hardware and software modules. It was conceptualized and designed by Pultrex into three configurations: continuous production, discontinuous production, and a combination of the two. In order to manufacture pipes and riser systems, a continuous system was developed with a winding head rotating around the part and continuously fed through the winding turntable. In this design, the laser is positioned on the turntable, which helps guide the laser to the tape winding head. Depending on the application and winding settings, up to four heads can be mounted on one turntable and multiple turntables can be placed in the production unit. Electricity, compressed air and cooling water are supplied through a series of slip rings.

System design for continuous and discontinuous production

The discontinuous system of parts such as pressure vessels uses gantry robots for maximum flexibility. The third configuration is a combined production unit for continuous and discontinuous production, designed to achieve rapid automated changes between the two production scenarios. In order to save excess investment costs, a mechanism for effectively changing the tape winding head and the laser system between the two production schemes was designed. Belted winding heads and associated control units are used in all system configurations, developed and improved by Fraunhofer IPT. The development of ambliFibre has improved the modularity and flexibility of production technology, enabling the production of tape winding technology and control solutions for customers and specific applications.

Life cycle cost
System development in ambliFibre is supported by Mach4Lab’s new reliability and maintenance model, which simulates and predicts machine fault conditions during early design phases and helps select cost-effective maintenance strategies. To this end, field production and failure data were analyzed and reliability and maintainability indicators were derived. Based on this, a maintenance cost model was developed and implemented.

The model evaluates the cost of each maintenance intervention on the machine up to the component level and enables the user to compare different situations, including corrective and preventive maintenance, to optimize from the design stage of the tape winding system throughout its useful life. select. The life cycle cost model can be applied to both continuous and discontinuous tape winding machines.

Last part
Focusing on products made with the ambliFibre tape winding system, Life Cycle Engineering evaluates environmental impact and life cycle scenarios. Environmental performance is the benchmark for composite pipes and pressure vessels. The detailed assessment takes into account raw materials, transportation and manufacturing, and end-of-life use. A user-friendly web tool was developed to identify key environmental indicators, such as the carbon footprint of different lifecycle scenarios. With this tool, you can assess and demonstrate the potential and efficiency of a green production strategy.

in conclusion
The use of thermoplastic fiber reinforced plastics instead of metals offers great potential for offshore applications, such as riser systems in deep water applications, where the high strength-to-weight ratio of these materials significantly increases the structure’s supportable weight. The composite layer can be manufactured by an automated laser-assisted tape winding process, and the ambliFibre project seeks to increase process stability and quality assurance to another level. New simulation and data mining tools open up the possibility of reducing the acceleration time of new production scenarios and, in combination with new adaptive laser optics and high-speed thermal imaging cameras, reliably control process results. The add-on module monitors the quality of the merge between layers during the process and provides immediate feedback to the operator. Models for evaluating system maintenance strategies and product environmental performance support the creation of sustainable and reliable system technologies and lightweight products. In addition to continuous production systems for the manufacture of pipes, discontinuous systems for components such as pressure vessels and combined production units have also been developed for the industry. The modular approach to system design allows customers to adjust the laser-assisted tape winding manufacturing system to suit their applications and products. Models for evaluating system maintenance strategies and product environmental performance support the creation of sustainable and reliable system technologies and lightweight products. In addition to continuous production systems for the manufacture of pipes, discontinuous systems for components such as pressure vessels and combined production units have also been developed for the industry. The modular approach to system design allows customers to adjust the laser-assisted tape winding manufacturing system to suit their applications and products. Models for evaluating system maintenance strategies and product environmental performance support the creation of sustainable and reliable system technologies and lightweight products. In addition to continuous production systems for the manufacture of pipes, discontinuous systems for components such as pressure vessels and combined production units have also been developed for the industry. The modular approach to system design allows customers to adjust the laser-assisted tape winding manufacturing system to suit their applications and products.