OsecoElfab’s FRDI Rupture Disc Holder

The OsecoElfab FRDI Insert Rupture Disc Holder is a reduced diameter, flat-faced flange assembly that bolts between standard ANSI pipe flanges and fits within the bolt circle. The FRDI has a flat seat, and uses a raised nubbin sealing surface to create a metal-to-metal “bite” seal between the FRDI inlet, and the rupture disk inlet seat surface.  This holder allows the rupture disc to be preassembled to ensure it is properly seated before installation into the pressure systems. FRDI Insert Holders are available in standard ANSI flange ratings up to 42″ and are offered in three overall height arrangements.

  • The FRDI is for use with the FAS, F(CO) and (F)STD rupture disks.
  • The FRDI is compatible with the AMS, SVT, and LPSF burst disk indicator sensors.
  • The FRDI is available in line sizes ranging from 0.75 inch diameter all the way up to 42 inches diameter.
  • The FRDI is compatible with service temperatures ranging from cryogenic temperatures all the way up to 900 degrees F.
  • The FRDI is available in all OE standard materials (316 Stainless Steel, Nickel 200, Inconel 600, Monel 400, and Hastelloy C 276).  Other materials may be available or offered on request. The inlet ring material can be specified as a different material than the outlet ring material.
  • The FRDI works well in gas or vapor services, as well as liquid or two-phase services.
  • The FRDI may work well in sticky or fouling services, although alternative holder designs such as the TopHat Assembly are recommended in such environments.
  • The FRDI is considered non-torque sensitive. While proper torque procedures should be followed during installation, the FRDI is fairly tolerant of over-torque, or slightly uneven torque of the bolts on the companion flange.
  • The FRDI is available in ANSI 150#, ANSI 300#, ANSI 600#, ANSI 900#, ANSI 1500#, and ANSI 2500# Flange Classes
  • The FRDI is available in Raised Face, Flat Face, Crush Ring, and RTJ flange facing arrangements.
  • The FRDI can be tapped for instrumentation on both the inlet and outlet rings.
  • The FRDI can be offered as a double disk assembly, allowing for the installation of two rupture disks in series.
  • Kr values are specific to the rupture disk model used. As such, the FRDI does not have its own, unique Kr value.
  • Operating Ratios are specific to the rupture disk model used. As such, the FRDI does not have its own, unique operating ratio.
  • Manufacturing Ranges are specific to the rupture disk model used. As such, the FRDI does not have its own, unique manufacturing range.
  • Burst Tolerances are specific to the rupture disk model used. As such, the FRDI does not have its own, unique burst tolerance.
  • Fragmentation is specific to the rupture disk model used. As such, the FRDI is neither fragmenting nor non-fragmenting.
  • A 1” FRDI has a standard overall height of 1.62”. Custom height FRDI’s are available upon request.
  • A 1.5” FRDI has a standard overall height of 1.62”. Custom height FRDI’s are available upon request.
  • A 2” FRDI has a standard overall height of 1.62”. Custom height FRDI’s are available upon request.
  • A 3” FRDI has a standard overall height of 1.62”. Custom height FRDI’s are available upon request.
  • A 4” FRDI has a standard overall height of 1.87”. Custom height FRDI’s are available upon request.
  • A 6” FRDI has a standard overall height of 2.50”. Custom height FRDI’s are available upon request.
  • An 8” FRDI has a standard overall height of 2.87”. Custom height FRDI’s are available upon request.
  • A 10” FRDI has a standard overall height of 3.12”. Custom height FRDI’s are available upon request.
  • A 12” FRDI has a standard overall height of 3.62”. Custom height FRDI’s are available upon request.
  • The factory should be consulted for the overall height of any FRDI above a 12” line size.