ABB-STAL uses since 1986 VERAX designed pipe joints in their  VAX high pressure steam turbines. In hundreds of thousands of operating hours ( up to date 97 installations in 17 countries ) those VCF-joints have never presented any kind of problem.

Each VAX turbine consists of some 25 VCF-joints for "internal piping" with full metal-to-metal contact. No seal required.