A state-of-the-art tube bending machine is giving BAE Systems Submarine Solutions greater flexibility to fabricate complex part shapes required to build the UK's Astute class nuclear-powered submarines.
Supplied by Unison, the all-electric tube bender features both right and left handed bending capability. This allows long and complicated tubular part shapes to be produced rapidly and in a single stage. For BAE Systems, this is a critical advantage, as the boat building process must run to plan and many parts are produced on demand to satisfy the production schedule.
When fabricating tubular shapes of several metres in length, the new machine also allows BAE Systems to make parts from a single length of tubing, avoiding any need to join tube sections. In addition to production speed advantages, this new capability also eliminates time-consuming and expensive X-ray and crack-detection testing stages.
The new 20mm machine has been purchased to increase the production capacity and flexibility of the pipe shop at the BAE Systems’ Barrow-in-Furness shipyard. It joins a number of hydraulic tube bending machines. The first right and left handed machine, the new equipment is also the shipbuilder's first 'all-electric' tube bender with position control achieved through servomotor-based movement axes.
In order to fit in all of the submarine's equipment and maximise the free space available, small-bore piping and tubing services such as hydraulic lines are often shaped to fit into the free spaces available adjacent to panels and bulkheads. Consequently, tubular parts are often fabricated in batch sizes of just one.
The Unison tube bender is making it quicker to produce components, as programs are simply loaded from the design database, and bends are then made precisely by the servomotor movement axes with their closed-loop control mechanisms. No manual intervention or adjustments of any kind are required. If the tooling is already on the machine, the set up operation is achieved in around 15 minutes or less.
A power consumption reduction is another intrinsic advantage of the Unison bender. As there are no hydraulic pumps continuously running, significant electrical current is only drawn when the machine is making a bend, so energy consumption is reduced substantially.
BAE Systems chose Unison for the machine because of their reputation. Unison have produced machines for some demanding applications including naval shipbuilders and aerospace companies.
Unison allows an engineer to make a service call within hours of a problem emerging. Another useful aspect of the machine is its incorporation of sophisticated software-based facilities that can be used for fault diagnosis. These include a camera that can be used to capture images or video of any operational problems. In combination with a software 'black box' which automatically stores the last 500 instructions entered by the operator, along with details of machinery positions from the servo motor sensors, Unison have detailed information to provide remote maintenance advice.
The Astute programme is a demanding engineering project currently under way in the UK and the nuclear powered attack submarine has been described as 'more complex than the space shuttle', involving nuclear weapons and stealth technology operating in the most hazardous environment on the planet. An Astute class submarine has a million individual components and 10,000 separate design and engineering requirements.
According to Alan Pickering of Unison, for naval shipbuilding a constant stream of application-specific parts are required, and typically need to be produced just-in-time as work progresses along the vessel. The software-centric nature of all-electric tube bending machines with their attributes of fast and accurate set-up, and precise bending, provides versatile automation to support this highly dynamic work environment.
To save space, the new tube bender incorporates on-machine guard panels. This feature will additionally simplify moving the machine if required, for any reorganisation of the shipyard required for subsequent construction projects such as the UK's 'Future Aircraft Carriers'.