Development of a reliable quality control system using advanced Non-Destructive Evaluation (NDE) technologies for the production environment of leak-free fuel tanks from plastics and composites

Project Information

LeakFree

Grant agreement ID: 673155

DOI

10.3030/673155

Project closed

EC signature date 1 May 2015

Start date 1 June 2015

End date 31 March 2017

Funded under

• SOCIETAL CHALLENGES - Smart, Green And Integrated Transport

Total cost

€ 1 196 286,75

EU contribution

€ 837 400,73

Coordinated by

FLOTEKS PLASTIK SANAYI VE TICARET AS
Türkiye

Periodic Reporting for period 2 - LeakFree (Development of a reliable quality control system using advanced Non-Destructive Evaluation (NDE) technologies for the production environment of leak-free fuel tanks from plastics and composites)

Reporting period: 2016-03-01 to 2017-03-31

Summary of the context and overall objectives of the project

The project LeakFree is expected to increase the efficiency of the quality monitoring and management processes that currently run at fuel tank production factory at Floteks. The project is supposed to meet the overall objective by meeting the hardware and software challenges that automatic inspection,i.e. not visual inspection, of the fuel tanks on the production factory require. This includes automatic setup of the fuel tank for test, communication with system and finally communication with the IT infrastructure of the factory ERP.
There is no standard / common regulation for the leakage detection system of fuel tanks in automotive industry. So, the most important aim of this Project will be to persuade various OEM’s on one single system, meaning LeakFree system, which will elevate many weaknesses of the conventional systems used.
Major factors in automotive industry are security, protecting the environment and quality assurance. Therefore, suppliers to the industry must adjust themselves to the high quality assurance systems. There are many different methods of detecting leakage from the tanks. However, the complexity and high cost of some systems make it not feasible. Although leakage detection of fuel tanks is a major issue in automotive industry, there is no consensus among the OEM’s how to detect leakage.
The LeakFree project aims to develop a low cost leak detection system that will be fast, accurate, reliable, reproductive, with data acquisition to the supplier’s QC and logistics ERP system, making the data produced traceable. It should also be automated within mass production environments. The solution will be primarily developed for automotive industry and their fuel tanks suppliers. The system will be feasible to buy and to use for the suppliers to the OEM’s.
The LeakFree system’s philosophy is to listen to the bubbles evolving from pressurized tank dived under water using hydrophones. The main challenge of the project is to have a system that is working in industrial factory environment with noise levels that are not only high, but also inconsistent depending on the activity. Environmental sound should be filtered out.
A software has been developed to control the LeakFree inspection process. The software communicates with the PLC system controlling the developed automated mechanical system to perform the physical actions of the test, place the tank in the pool, pressurise it, and remove the tank from the pool once the test has ended. In addition, the LeakFree software communicates with the ERP system of the company in order to receive the testing parameters (recipe) for each tank, and then send the inspecton results to the ERP system for storing them along the whole history of the tank. The whole inspection process is controlled by a user friendly Graphical User Interface (GUI) and it was implemented in Turkish as well.
NI DAQ h/w has been assembled, hydrophone sensors purchased and a pool constructed for the tests. For this:
1) An automated, diving system of the tank to be tested into the pool has been constructed.
2) Automatic welding systems for plastic parts, to weld to the other plastic parts, sensors and accessories airtight to them, was developed. The welding parameters are to be adjusted to achieve parts accepted as “airtight”. The development of the automated spin welding in Floteks is also a side product of this Project.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

The optimisation of the h/w and the sensors during RP1 allowed to have a system and to test it in quiet environment. In order to achieve this:
- IKH designed and developed the Control software. This allowed the system to be part of the whole manufacturing process real time.
- Development work has focused on fine-tuning the communication between the control software and the ERP system operating at Floteks industrial environment.
- All experiments were carried out at Floteks’ factory environment.
The summary of the steps for the work is as follows:
o 19th July 2016; Environmental noise measurement using microphones in the test pool,
o 9th, 10th August 2016; LeakFree Automated and sound isolated Test Pool at Floteks factory Shop Floor,
o 21st October 2016; LeakFree Automated Test Pool with the deployed new algorithm,
o 6th November 2016; Sensitivity tests of the algorithm based on laser drilled nozzles with different hole sizes.
- Floteks then built a new pool with better sound isolated lid to allow continuous testing of the leakage and shared the data with BIC to allow optimisation of the algorithms
o 4th December 2017; Sensitivity tests of the algorithm based on different distances between hydrophones and leakage usin
o 28th , 29th December 2016, 22nd January 2017; Further tests on the LDH’s using deployed enriched new algorithm,
o 22nd February 2017; tests repeated with BIC and IKH participating,
o 13th March 2017; tests repeated for the demonstration with BIC and IKH participating.
- BIC used the data provided by Floteks and explored different statistical tools and signal processing tools.
So, although successful to a great extend, the leakage detection using Leakfree system as developed so far was not at TRL9 level and needs to be improved further.
o During the period of development of Leakfree system, Floteks managed continuous communication with the supporting RTDs by:
 Planning conference calls,
 Planning 9 face to face meetings.

Floteks organised an excellent commercialisation event attended by the business press, the end users (mainly automotive), NGOs and academics and demonstrated the Leakfree product, showing the 100 % reliable detection of bubbles from various LDN’s.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The tank suppliers to the automotive industry today are using mostly the system of pressurizing their tanks under water, then watching the building and escaping of the bubbles. This quality control method is accepted by the industry only because there is no alternative to it. Such control of the product doesn’t allow to generate any standards for the industry to agree on and could lead to some leaking tanks being sent just because of the lack of vigilance of the operator. A control quality process can’t rely on human observation as it is not reliable by definition and it is sensitive to the physical condition, the health and the psychological status of the individual carrying the test.
Not only will Leakfree system allow the reduction of the cost of the inspection by installing a technology that allows:
- Quick and reliable inspection of tanks as it doesn’t rely on human observation
- Built-in redundancy as the quality of the measurement is confirmed by more than one hydrophone.
- Finally, in a quiet environment, the leakfree algorithm output is directly correlated to the size of the leaking hole.
- In the medium term, the leakfree system could lead to standards adopted by the industry. This not only will help controlling the quality of fuel tanks, but would allow Floteks to expand its market significantly and to enhance its image as a pioneer of this quality control process and the subsquent standard.
The leakfree product once perfected will allow the industry to have more reliable fuel and adblue tanks which consequently means less leakage of chemicals to the environment. This system could also be used to monitor LNG, Hydrogen and other gas tank leakages. This is particularly relevant to applications where the gases are either toxic or harmful to the environement, and/or explosive.

Leakfree Spin Welding station with its GUI

Leakfree pool w/o isolation

Leakfree Welding Station panel

Leakfree Welding Surface Trimmer apparatus

Leakfree isolated pool

Leakfree Welding Station with GUI

Leakfree pool and GUI panel w/o isolation

Leakfree pool system simple cad drawing