YARDLEY, Pa.--Bluefin Robotics needed to find a method for fastening structural plastic components used in its autonomous underwater vehicles (AUVs). Located in Cambridge, Mass., Bluefin manufactures underwater vehicles designed for military, commercial, and archaeological exploration and research.

"The specifications called for a threaded insert for fastening plastic structural components together," said Mike Szegedi, manufacturing engineer at Bluefin. "The inserts needed to provide enough strength to prevent the fastened components from pulling apart under any stress."

Bluefin engineers conducted a search that led to some specifications for threaded metal inserts from Yardley Metal Products Corporation, a manufacturer of threaded metal insert fasteners. They ultimately chose Yardley Trisert^® stainless steel threaded metal inserts--designed to produce strong threads in plastics, soft metals, and wood--for the application. Trisert^® inserts are self-tapping and provide high torque and pull-out resistance, according to Yardley.

A metal insert was used instead of a plastic insert because of its ability to provide greater strength and to resist stripping of the threads under stress. The material of choice, due to its superior corrosion resistance in the harsh sea water environment, was 316 stainless steel.

Yardley Products (www.yardleyproducts.com) manufactures precision-engineered, threaded metal inserts that are designed to "lock" securely into plastic, metal, or wood base materials. In addition to stainless steel, threaded metal inserts, the company manufactures standard and custom inserts that can be installed as pressed-in, molded-in, epoxied-in, self-tapping, ultrasonic, and thermal-insert fasteners.

"The list of applications our fasteners are found in is extensive and broad," said Tim Bailey, president of Yardley Products. "Our relationship as a supplier to Bluefin is a classic example of an application telling the story of our products more effectively than the product specifications ever could."