Hot Drape Former - BAE Systems

Objective

BAE Systems wanted to implement new technology as part of a capacity and process expansion. The specification for this bespoke machine called for a compact and self-contained unit, that would give higher quality parts through tight control of the process while also improving user ergonomics.

The existing machine was an ageing piece of equipment that was using legacy technology and was restricted in capacity both from a cycle time and performance perspective. In order to futureproof production for newer more complicated parts and to improve quality, BAE approached PAC Group to provide a new Hot Drape Former.

Process

Two of our specialist divisions, PAC Composites and PAC Automation, collaborated to design, manufacture and install a Hot Drape Former which included an internal vacuum pump capable of producing in excess of -900mBar vacuum.

This high level of vacuum helps produce excellent conformity of the applied composite to the tool. This coupled with the integrated custom exhaust filter and the forced air cooling system means the machine is almost totally self contained, requiring only a pneumatic and electric supply. This allowed for a simplified installation and ensured minimal disruption to current production

Heating Systems

Infrared

All of our Hot Drape Formers feature a quartz infrared heating system to soften the carbon fibre quickly and evenly. This is to allow the layers to slip against each other, producing accurate parts that are free from any stress wrinkling. This system utilises a bank of x24 750W heaters..

Heating control

The Performer was equipped with pyrometer-controlled heat monitoring allowing for an extremely accurate part surface temperature reading with thermocouples providing overtemperature protection. The pyrometers control four separate heat zones all with six lamps each.

Features

Using our specialist knowledge and award-winning patented technology, we equipped the hot drape former with:

• Flexible Zoning – any part of any size, up to the machine’s maximum dimensions, can be created through the use of programmed ‘zones’. This significantly reduces production time and energy costs.
• Silicone Diaphragm - the Preformer is fitted with a silicone diaphragm on a removable frame for ease of replacement.
• SMART Software – created by PAC Group, the software that controls the machine learns the production profiles. This ensures that parts are created right first time, which significantly reduces wastage. In addition, the machine can self-diagnose faults and alert the operator when conditions fall outside of the accepted range.
• Fully Bespoke – PAC can produce ‘standard’ Preformers. However, each element – from the size of the machine, to how it loads, to the location of control panels and sensors - can be customised based entirely on client needs and preferences.
• Patented Technology – PAC Group holds 42 patents on the Preformer hardware and software.
• Breakout Box - The table includes vacuum tight breakout boxes for connection of temperature thermocouples to the tool.

Safety and Ergonomics

For optimum operator accessibility, the vacuum table can be manually pulled out from the machine which allows for more ergonomic tooling placement and fabric layup.

To further enhance operator safety, front and rear light curtains were added to enable a safe and effective emergency stop in the event an operator attempts to access moving parts of the machine. This allows the operator safe access to the machine without the need for physical guards, improving cycle time and ease of use.

Challenges

• Tight deadline - ​​Due to BAE’s production targets, we had to work to a very tight schedule and deliver the Preformer within seven months.
• Supply chain difficulties - At the time of manufacture, Brexit affected our ability to take delivery of essential parts. To overcome this challenge we worked with alternative suppliers who were able to produce parts and components to our specifications and quality requirements.
• Machine footprint - The available location for the machine on BAE site was restricted, therefore the overall machine footprint had to meet a size of 2.9m X 1.7m with an active working area on the table of 1.6m X 1m.

Outcome

PAC Composites successfully manufactured the bespoke hot drape former to BAE Systems’ specification on budget and within the required timeframe.

Following a SAT (Site Acceptance Test) in which BAE Systems tested the Preformer at the PAC workshop in Belfast we arranged delivery of the machine to the customer site in Samlesbury, Lancashire.

The finished machine was successfully delivered and installed on-site by a highly experienced team from PAC Automation, with the assistance of SCADA engineers within the specified timeline.

Once a FAT (Factory Acceptance Test) was completed BAE Systems confirmed they were highly satisfied with both the quality of the product and the service PAC Group have provided.

Technical Specification:

• Fully self contained hot drape former unit
• Integrated electrical and pneumatic panels
• Single Diaphragm unit with fully removable diaphragm frame
• x4 fully controlled heating zones of x6 750W lamps each in an insulated hood
• Machine footprint of 2.9mW x 2.9mH x 1.7mD with an active heating area on the table of 1.6m x 1m
• Sliding vacuum lay-up table for enhanced operator ergonomics
• Integrated adjustable fans provide forced cooling with workshop air
• Requires a single electrical supply

Contact our team today for more information on our bespoke hot drape forming machines, or to discuss your specific requirements with our specialist engineers on 02893 364600 or email info@pacgroup.co.uk