Examples bursting disc

In all cases where combinations of bursting disc devices with SRVs are used, measures must be taken to ensure that the space between the valve seat and the bursting disc is kept at atmospheric pressure Any increase of pressure in this cavity due to, for example, temperature changes, minute pressure leaks, and so forth, will result in a dramatic and uncontrolled change in opening pressure of the safety system. Also, with this combination the SRV must be 10% oversized to accommodate the eventual pressure drop over the bursting disc. 

This program contains an example of conditional statements. A conditional variable DISC is defined such that if DISC =1 then the bursting disc is intact, and if DISC =0 the disc has burst. The discharge velocity through the disc varies with pressure as given by the complex conditional statement in the partial listing below ... 

Example 7.1 Dimensioning of a safety valve and a bursting disc for the pressure relief of a liquid... 

The term set pressure is used to denote the pressure at which the relief device is open fully. This is not the definition used by some — for example, British Standards. For a safety valve the set pressure is often 10% above the set pressure as specified by the manufacturer or measured in the workshop, since this higher pressure is needed to open the valve fully. For a bursting disc, the set pressure is the nominal burst pressure plus any tolerance (or alternatively it is the maximum specified bursting pressure). The term overpressure is used here to mean the difference between the (redefined) set pressure and the maximum pressure reached during the venting process. 

A bursting or rupture disk is a pressure relief device that protects a vessel or system from excess pressures. They have been commonly used in aerospace, aviation, defense, nuclear, and oilfield applications often as a backup device for a conventional safety valve. In this instance, if the pressure increases and the fitted safety valve fails to operate, the rupture disk will burst as required. The discs are usually made from thin metal foil, and gold has been used in some instances because of its ductility and resistance to corrosion. Gold discs fitted to liquid ammonia tanks, for example, have shown good durability in this application compared to other metals. The use of gold in this application was reviewed in the 1970s when this industrial application for gold was more common [10]. 

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