Unique hydraulic connectors are leak-free

Dean Palmer reports on a unique connection system for high pressure pipework, that is leak-free and offers designers metal-to-metal sealing backed up by PTFE seals

A company that traditionally has supplied pneumatic components has ventured into the hydraulics arena by developing a unique, leak-free high-pressure connection system for DIN 2353 couplings that is leak-free. Legris' patented 'DiNova' connection system is unique in that it incorporates metal-to-metal sealing, further sealing through PTFE seals and extra protection of the back seal during installation, plus a mechanical stop that indicates whether the crimp has been properly achieved. Even if the original seal is properly made, vibration can cause parts to move and fluid to escape. At best, this can lead to a greasy, unsafe workplace but in applications such as braking systems, it can prove fatal. Malcolm Crossley, MD at Legris told Eureka: "If a pipe is jammed into the fitting, it can damage the seal and lead to a loss of integrity. The twin challenge has been to guarantee that components are secure through correct alignment and then properly sealed." The DiNova cutting ring features three gripping bites, with metal-to-metal sealing within a 24° cone and extra sealing through two PTFE seals. The soft PTFE material allows it to absorb any movement of the hydraulic connection while in use. Also, the PTFE seals can be used with virtually all aggressive fluids and in temperatures between -40°C and 200°C. The patented design also guarantees protection of the back seal during assembly, preventing pollution both within the sealing areas and of hydraulic circuits. The ring, body and nut are lubricated to prevent the risk of seizing, to lower tightening torques and to offer better perception of the mechanical stop. The connectors are fully interchangeable with traditional cutting rings and are Chromium 6-free in readiness for future legislation taking effect in 2006.