Tectra Automation designed and built an ultrasonic linear measurement bath for Denel Aerostructures. The bath will automate the scanning of composite components that Denel Aerostructures supplies to a specific line of military transport aircraft. It was recently delivered to the company’s Atlas Road facility in Kempton Park, Johannesburg.

The structure is a bridge crane system constructed from aluminium extrusions and linear motion technology from Bosch Rexroth, and is approximately 10 metres in length by 1 metre in width. The system automates an extremely precise scan path across the composite component to ensure the scanning of each part is executed with maximum accuracy.

The test will reveal any flaw or structural weakness in the composite material, alerting Denel Aerostructures to components that do not meet its stringent quality standards. An automated scanning process not only speeds up the testing process exponentially, it also enhances its production quality. With the bridge maintaining a uniform height across the scan path, the irregularities in scan heights characteristic of manual scanning can be avoided.

Achieving this precision in the scanning process was complicated by the large size of components. “We had to join two five-metre aluminium extrusions to get the required length of 10 metres,” explains Jaco de Beer, Project Engineer, Tectra Automation.

“Once we’d assembled this length, we noticed the aluminium was creating a minor sag along the length. To overcome this problem, we had to develop a series of customised struts and box-type frames to ensure they were perfectly horizontal. It is the longest bridge-type system we have built to date.”

The automation of the ultrasonic system is controlled by the extremely versatile, highly accurate single controller MTX Micro. “Programming the specified scan path, which it does via G-code, is simple and will be familiar to anyone working with CNC lathes and milling machines,” de Beer explains. “All that is required for programming, from an operator’s perspective, is inputting the correct length, width and indexing specifications.”

As Tectra Automation supports such an extensive stockholding of Bosch Rexroth products, it was largely in control of delivery time, and the system was built in less than eight weeks to meet the tight timeframe required by Denel Aerostructures.

 Tectra Automation also supplied specialised polyurethane backing which lines the surfaces of the bath to maximise the system’s suitability for ultrasonic linear measurement applications.

Tectra Automation, a Hytec Group company, is a leading drive control specialist providing solutions for industrial and factory automation applications.