Page 237 - Valve Selection Handbook

224 Valve Selection Handbook

Figure 6-3. Solid Forward Domed Rupture Disc Before and After Bursting in Gas
Service. (Courfesy of Continental Disc Corporation.)

Figure 6-4. Vacuum Support for Forward Domed Rupture Discs, Full Opening Upon
Bursting of the Disc. (Courtesy of IMI Marston Ltd.)

To guard the disc against further plastic deformation during service,
normal operating pressure is commonly restricted to 70% of the rated
burst pressure or less, depending on operating conditions.
Because the tensile strength of the construction material used for the
manufacture of the discs is fairly high, solid forward-domed rupture discs
for low pressures must be made of relatively thin foils. Periods of vacuum
or superimposed back pressure will therefore tend to cause the disc to par-