Page 228 - Valve Selection Handbook

Rupture Discs 215

Terminology

For the purpose of this book, the following terms are defined below:

Rupture disc device. A non-reclosing pressure relief device, consisting
of rupture disc and holder, in which the rupture disc is designed to burst
at a predetermined differential pressure across the disc.
Rupture disc. The pressure-containing, pressure and temperature sensi-
tive element of a rupture disc device.
Forward-domed rupture disc. A rupture disc that is domed in the direc-
tion of the fluid pressure and designed to burst due to tensile forces.
Reverse-buckling disc. A safety disc that is domed against the direction
of the fluid pressure and designed to buckle due to compression forces
prior to bursting or to being expelled from the holder.
Holder. The component of the rupture disc device that holds the rupture
disc around its circumference and consisting of the inlet and outlet holder
parts.

Vent panel. A low-pressure venting device designed to vent the near
instantaneous volumetric and pressure changes resulting from dust, gas,
or vapor deflagrations.
Vacuum support. A device that supports the rupture disc against collapse
due to vacuum pressure.
Back-pressure support. A device that supports the rupture disc against
collapse due to superimposed back pressure.
Heat shield. A device that shields the rupture disc from the heat source
in a manner that does not interfere with the rupture disc operation.
Specified temperature of rupture disc. The temperature at which the
disc is rated and marked.
Burst pressure. The differential pressure across the rupture disc at which
the rupture disc bursts at the specified temperature.
Marked or rated burst pressure. 1 The burst pressure at the specified
temperature that is marked on the disc tag by the manufacturer. The
marked burst pressure may be any pressure within the manufacturing
range, unless otherwise specified by the customer.

1
ASME Code (1992) Sect. VIII, Div. 1, UG 127 (a)(l)(b)