A global designer, manufacturer and integrator of precision motion control products needed universal joints for sensor applications of aircraft wing high lift actuation systems (HLAS). Because the company’s original universal joint vendor discontinued the product, it had to locate a new supplier who could satisfy an extremely tight production schedule quickly and skillfully. The new vendor had to be thoroughly familiar with manufacturing standards specific to the commercial aerospace industry. AS9100 qualification, which is scarce among universal joint manufacturers, was an additional requirement.
Aircraft universal joints must be manufactured to withstand the most demanding operating conditions—and the harshest working environments—with as little maintenance in the field as possible. Thus, low deflection rates, high strength-to-weight ratios and long service life are all essential.
The company chose Belden Universal, a manufacturer with extensive experience in designing custom universal joints for aerospace applications—including high lift actuation, flap opening, and steering and control mechanisms.
Engineering and quality management teams on both sides carefully reviewed design details and associated standards. The requested universal joints were to be used in aircraft fail-safe systems. Among the customer’s specifications were in-process control and marking requirements, along with performance and dimensional criteria.
One of the challenges was that the original product had been manufactured from a material only available through a European supplier. However, sourcing raw material from overseas would have resulted in critical time loss, making production from scratch out of the question. To circumvent these time constraints, Belden’s design engineers proposed an innovative solution: Applying a few minor modifications to the manufacturer’s existing Military Specification joints would allow them to stay true to the original part and still meet the customer’s Class 2 flight-critical application requirements. These joints are manufactured according to “MIL-J-6193” requirements. As a Mil-Spec “Qualified Product Listed” manufacturer, Belden had the necessary qualifications to manufacture the final product. Existing components in a suitable stage of the production process were rerouted, which allowed for the necessary modifications and supported the tight timeline.
To ensure optimal performance, every lot of these joints are also required to undergo MIL-J-6193 Group A Lot Compliance testing. In-house testing delivered immediate results, ensuring consistently high quality and reliability of the universal joints along with reduced lead times, when compared to outsourced testing.
The manufacturing process was further supported by a paperless inspection platform, allowing for easier maintenance of data. As opposed to traditional paper records where the operator manually checks off inspection and tool requirements, the platform automates, simplifies and speeds up procedures and enables all members of the production team to view live data at any time. It specifies what features to measure, the proper tools for measuring and selects inspection specifications for the various features and pieces.
The end result was a universal joint that fit, formed and functioned in the same fashion as the obsolete part, delivered on schedule and in compliance with the stringent specifications of the aerospace industry.
Filed Under: Aerospace + defense, Design World articles