Business Weekly - Cambridge, UK

With the ability to expose metals to a pressure of 1,000bar – over seven tons per square inch – and temp-eratures between -150ºC and 85ºC, the facility is being housed at TWI’s headquarters in Granta Park in a specially reinforced, blast-proof building, capable of absorbing an accidental explosion.

The development of the new test facility follows a programme in which the existing facility was built and tensile testing was carried at TWI for the Japan Research and Development Centre which is working closely with TWI Industrial Member, Nippon Steel Corporation (NSC).

The tests were carried out within TWI’s existing pressure vessel containing high purity hydrogen, at a pressure of 450bar. They were performed at both ambient temperature and 85°C. The work, in conjunction with similar testing in Japan by NSC, was done to provide input to Japanese planning for the hydrogen economy.

Hydrogen is widely recognised as the long term answer to fossil fuels as it can be produced from renewable energies or nuclear energy and can be used in fuel cells, advanced combustion engines in vehicles and in gas turbines for small co-generation and for medium to large-scale electricity production.

However, according to the European Commission, a major drawback is hydrogen’s very low storage density at atmospheric pressure, which would require a storage tank to be 3,000 times larger in order to store enough hydrogen gas to drive a car the same distance as one which runs on gasoline.

In particular, test data is required to ensure the safe performance of hydrogen storage and handling systems for automotive applications, on board vehicles.

The new tests will carry out fatigue testing as well as tensile, anticipating roughly 50,000 refuels during the lifetime of an automotive fuel tank.

TWI’s project leader for the hydrogen facility, Ruth Hammond, believes the test equipment’s ability to provide unique data could prove highly lucrative. “We are anticipating enough work to run both the new and older machine.

“The facility we have at the moment is the only one in Europe and with the new machine will be the only one in the world, so the market is potentially huge.”

Though a potential rival does exist in to TWI in Japan with the ability to test at 1,000bar, it not able to reach the low temperatures that the TWI machine will reach.

“These low temperatures are where we see the worst effect of embrittlement. It is anticipated that service temperatures as low as -80°C will be seen due to adiabatic cooling of the hydrogen as it expands,” said Hammond.

The facility to house and service the original mechanical test machine and pressure vessel was designed and built over some eight months, since then several tensile test programmes have been completed.

Development of the new equipment follows this successful development and utilisation of the first.

The new test vessel is in the design stage, with install-ation and commissioning due for completion later in the year and is located in an isolated building at Granta Park.

The building has a test booth for each pressure vessel, and a control room separated from these by thick steel doors, with a safety interlock.

The concrete walls are steel-reinforced, while the lightweight corrugated plastic roof over the test booth provides an easy escape path for any sudden pressure release or explosion, though TWI claims the combination of interlocks, gas and fire detectors and procedures, however, make this an extremely unlikely event.