Unison Ltd.

Intelligent Tube Bending Dramatically Reduces Lead Times

Dec. 8, 2021
Safran Landing Systems has partnered with Unison Ltd. to increase production and produce right-first-time parts.

Gloucester-based Safran Landing Systems OE (Original Equipment), part of the global Safran group, has installed two all-electric ‘Breeze’ CNC tube bending machines from UK-based Unison Ltd.

The Unison Breeze machines (16 and 30 millimeters maximum tube diameter models) will be used to precision bend thin-wall section titanium tube for the manufacture of 3/8 (9.53) to 3/4-inch (19 millimeters) diameter hydraulic brake and actuator pipes for commercial aircraft undercarriage systems, including those used on Airbus A320, A330 and A340 models. They replace two hydraulically operated tube bending machines that have been in use at Safran for a number of years.

“Realizing it was time to renew our tube bending capabilities, as part of our ongoing risk analysis activities—and necessitated by significantly increased manufacturing requirements—we approached a number of tube bending machinery manufacturers to discuss the various options available to us,” comments Safran Assembly Flow Line Manager, Jonathan Crewe.

“Absolute non-negotiables were uncompromising repeatability and reliability, as well as the ability to produce right-first-time parts. Additionally, as a key manufacturer of aerospace components and operating within a ‘just-in-time’ supply chain, it was essential for us to know that should it ever be needed, on-site machine tool support would never be more than a few hours’ drive away.”

Existing Customer Visit

To enable the Safran team to experience first-hand the capabilities of its all-electric range of Breeze tube bending machines, Unison Ltd arranged for them to visit an existing customer’s facility at Farnborough and observe titanium tubes being bent. On the strength of the visit and the testimony provided by that customer, trial parts were produced at Unison’s UK-based manufacturing center, the order was subsequently placed, and master pipe samples were supplied to Unison Ltd in readiness for machine setup and sign off.

Excellent Support

“We benefited from excellent support and advice at every stage of the process,” adds Jonathan Crewe. “We were particularly impressed by the effort Unison put into training, ensuring that our operators were fully familiar with the Unibend operating system and could confidently bend thin-wall titanium components, all with precisely controlled levels of spring-back to compensate for the material’s high yield strength. Unison was also exceptionally flexible in working around our incredibly demanding production schedules. We have produced right-first-time components since day one with our Unison Breeze machines, which our operators rate highly. Unison also fully understood our need for prompt support in the unlikely event of a breakdown—an essential requirement of our risk analysis strategy and a clear benefit of us buying from a UK-based company.

“On a personal note, I am really impressed with the performance of our two machines,” he continues, “and, in particular, the opportunities the technology opens up for us to streamline our workflow from Design Engineering through to Production, with the electronic translation of a CAD model into a bending program. This dramatically reduces the lead time of new product development from around eight months to just three days and improves the accuracy of the finished pipe to the initial design intent. I am also grateful to the team at Unison for their timely and professional assistance through the industrialization phase of the project.”

Intelligent Tube Manipulation

Unison Breeze machines offer rapid setup, fast tooling changes, exceptional power, rigid mechanical design, and all-electric control for right-first-time repeatability. The Unison Breeze all-electric 16 and 30 millimeters tube bending machines purchased by Safran are well suited to manipulating exotic alloys such as titanium and Inconel, as used in the aviation industry and provide high-quality thin-wall bending. Multi-stack tooling allows the most complex of parts to be formed in one uninterrupted manufacturing cycle, while Unison’s bar code scanning system ensures that only the correct tooling is used. Unison’s standard-fit rise and fall pressure die can result in significant savings in tooling costs and allows tools of very different radii to be used on a part within a cycle. Each tube bender can be programmed manually or from CAD data using industry-standard IGES or STEP files.

“At Unison, we are often invited to advise customers across the aerospace industry on particularly challenging tube bending projects,” concludes Steve Haddrell. “That’s partly because of the immense capabilities offered by our all-electric Breeze tube bending machines. It was an honor to be chosen to supply Safran with two machines—and to be recognized for the exceptional levels of service that are associated with the Unison name.