Mounting options
We divide up our range of bursting discs into:
a) three basic types and
b) 5 methods of installation:
a) These are rupture discs, composite bursting discs and reverse buckling bursting discs.
In the case of the rupture discs a foil is loaded with tensile stress by means of pressure. On reaching the tensile strength the foil ruptures. This simplest type of bursting disc is frequently used in the smallest bursting discs and at higher pressures. In order to reduce the bursting pressure and to force non-fragmenting, defined opening behaviour, rupture discs can be equipped with a fracture line, i.e. scored.
Composite bursting discs are made of laser-slotted metal foils, which determine the pressure and the opening behaviour, and of an internal sealing film, usually made of PTFE. The bursting pressure can be reduced a great deal by means of the cross section, for example in the case of DN 150 right down to 25 mbar. However, the temperature range in which composite bursting discs can be used is limited to a maximum of 200°C by the internal sealing foil made of PTFE.
Reverse buckling bursting discs work according to the principle of Euler's buckling rod: they are cambered against the direction of pressure; on reaching the bursting pressure the assembly turns down and opens at a pre-stamped nominal fracture point. They are scored full metal bursting discs. They are very resistant to high operating pressures and alternating pressure loads and to high operating temperatures.
b) The following distinctions can be made between the various methods of installation:
- Installation between flanges
– most frequent method of installation in chemistry, in container
and plant construction. We produce sizes from DN 15 to DN 900.
- Installation in a fitting - these are VCR fittings for high-vacuum and high-purity gas systems or clamping ring fittings
for a wide variety of purposes, but also customer-specific special
fittings. The torque and sealing system must be adapted to the specific
use. The bursting discs can be replaced after responding.
- Installation in sterile or clamp fittings:
When provided with a special split seal, our bursting discs can be
installed directly into clamp fittings. If reverse buckling bursting
discs are used, we achieve a sterile surface without any clearance
space.
- Bursting plugs-
In this case, the bursting disc (usually a rupture foil) is welded or
soldered on to a screw. Installation is very simple, saves space and
secure. Very high levels of imperviousness are achieved. A typical
application is, for example, extruders. After responding, the entire
bursting plug must be replaced.
- Welded-on bursting discs are used e.g. in the automotive sector in airbag cold gas bottles or lithium batteries. However, this space-saving and permanently tight connection can be advantageous in many other cases. Bursting should occur rarely, though, because an isolated replacement of the bursting disc is not possible.