There are few more aggressive environments in motorsport than the inside of an F1 fuel tank. Components in the fuel tank are immersed in volatile, high grade racing fuel and subject to cornering forces of up to 3.5G as well as intense vibrations from engine components that spin at up to 19,000rpm during racing. They face an even bigger test during refueling at pit stops, when a new fuel load is blasted into the tank at speeds of up to 12 litres per second. Ensuring that the electronics that control the submerged fuel pumps and level sensors can operate reliably in these conditions is a significant challenge. Total reliability is imperative too as, sealed in the flexible polymer tank liner, there is little chance of repairing or replacing these components during a race weekend.
Norfolk-based motor sport technology specialist BERU F1 systems has substantial experience in the delivery of robust wring solutions to the F1 industry. The company designs, develops and manufactures wiring components, sensors, stress measurement systems and composite parts. Its parts are used by every F1 team and in many other motorsport formulas. In its latest generation of wiring harnesses for F1 and endurance vehicles BERU F1 Systems is enhancing the performance and reliability of connectors in the critical fuel tank environment by potting them in an advanced epoxy compound from 3M.
DP490 is an advanced, filled, structural epoxy adhesive. It offers one of the best combinations of high strength and toughness in the 3M range of versatile EPX structural adhesives and combines high bonding performance with gap filling abilities and ease of working, characteristics that come to the fore in the BERU F1 Systems application.
For the fuel tank application BERU F1 Systems built a special mould that was used to encapsulate the special Souriau motorsport connector which connects the pump in DP490, together with the first 25mm of the power and control cable. The high strength epoxy material resists all the conditions in the fuel tank and, when the connector is assembled, it prevents any fuel entering the wiring system.
Connectors sealed with DP490 have been run in several major race series to date, including F1 racing and the Le Mans Endurance Series. To date, there have been no connector failures in use.
DP490 is used by BERU F1 Systems in other areas of motorsport assembly, notably to bond carbon fibre boxes containing control electronics, another application where the product’s high strength and vibration resistance is key. The introduction this year of V8 engines in F1 has increased vibration levels significantly and made vibration resistance a key priority.
The company uses 3M products widely, including doubled sided adhesive tapes to hold components in position inside connector boxes, where packaging constraints preclude the use of conventional mechanical fasteners. Scotch-Weld Hot Melt adhesives are used in the assembly of wiring harnesses onto composite frameworks prior to installation, and high density polyurethane adhesive tapes provide protection from abrasion for wires in high-wear areas.