UK manufacturer of high-performance engineered doors has successfully completed an 18-month project to design test and manufacture 19 fire-rated doors for a major North American rail tunnel.

The sliding, single-leaf fire-rated doors were designed at Rhino’s production facility in South Wales and built to withstand both positive and negative pressures from passing trains, as well as to combat fatigue from over one million loading cycles per year.

Built from carbon steel and protected with high-performance paint, the doors were tested to North American fire-rating standards (NFPA 252), subjected to 1,000-degree temperatures for 90 minutes and followed by shock loading from high-pressure fire-fighting hoses.

Following these rigorous physical fire tests, the doors were also assessed to BS 476 Part 22 and granted a 60-minute integrity rating.

The success of these tests demonstrated the doors’ ability in retaining structural integrity under harsh and challenging conditions, namely rapid changes in temperature.

Rhino, which has two manufacturing bases in the UK, recently scaled up the work taking place at its Lancashire site in order to meet this major project’s upcoming deadlines for delivery and installation.

Dr Chris Norris, Group Engineering Director at Rhino Engineering Group, commented: “After nearly two years of work designing, testing and manufacturing the doors, it’s great to see the hard work of our team pay off as the contract draws to a close.

“The success of this North American rail tunnel project, alongside our recent work at London Underground’s Bank Station, is cementing our reputation in the global transport sector.

“We’re now looking forward to putting our team’s expertise to task in future rail projects, continuing to provide our critical infrastructure clients with the strength to protect.”

This door type (Rhino-FD90SLP) is now available for future projects where fire-rated cross passage escape doors are required. Learn about Rhino’s work on major rail projects here and find out more about Rhino’s range of products by visiting the website here.