Rupture disc device

An important application of a rupture disc device is at the inlet of a pressure relief valve. The sizing of the pressure relief valve or rupture disc device combination requires that the pressure relief valve first be sized to meet the required relieving capacity. The normal size of the rupture disc device installed at the inlet of the pressure relief valve must be equal to or greater than the nominal size of the inlet connection of the valve to permit sufficient flow capacity and valve performance. The failure modes of rupture discs are [40] ... 

A rupture disc device is a non-reclosing pressure relief device actuated by inlet static pressure and designed to function by the bursting of a pressure containing disc. 

A rupture disc is the pressure containing and pressure sensitive element of a rupture disc device. 

The minimum net flow area is the calculated net area after a complete burst of the disc with appropriate allowance for any structural or support members that may reduce the net flow area through the rupture disc device. The net flow area for sizing purposes should not exceed the nominal pipe size area of the rupture disc device. 

The coefficient of discharge method (Kj = 0.62) was specified to calculate the capacity of the rupture disc device. However, the validity of this method is limited to a disc mounted close to the pressure vessel and the discharging to atmosphere. The ASME Code provides guidance for the limited use of this method ... 

Significant changes by the ASME Code have been employed that now have direct impact on the use of rupture disc devices. The change to the Code affecting rupture disc manufacturers is the application of the UD Code symbol to rupture discs that meet the requirements of the ASME Code. Authorization to use the UD stamp is based on an audit by an ASME representative of various manufacturing, testing. 

Rupture disc device A device that contains a disc which ruptures when the static differential pressure between the upstream and downstream side of the disc reaches a predetermined value. A rupture disc device includes a rupture disc and may include a rupture disc holder with eventual accessories (e.g. pressure gauge) (Figure 3.1). 

Burst pressure The value of inlet static pressure at which a rupture disc device functions. 

A diaphragm designed to burst at a predetermined pressure differential. A simple rupture disc device that is composed of a non-reclosing pressure relief device that relieves excessive static inlet pressure via a rupture disc. 

The client insisted on a test. The smoke detectors worked, and the explosive charge operated, but the cutter did not cut the rupture disc. The explosive charge could not develop enough pressure because the volume between it and the rupture disc was too great. The volume had been increased as the result of a change in design installation of a device for discharging the halon manually. 

Failure of relief devices, e.g. pressure relief valves or rupture discs. 

There are two general categories of relief devices (spring-operated and rupture discs) and two major types of spring-operated valves (conventional and balanced-bellows), as illustrated in Figure 8-7. 

Rupture discs are specially designed to rupture at a specified relief set pressure. They usually consist of a calibrated sheet of metal designed to rupture at a well-specified pressure. They are used alone, in series, or in parallel to spring-loaded relief devices. They can be made from a variety of materials, including exotic corrosion-resistant materials. 

When rupture discs are used before a spring-loaded relief, a pressure gauge is installed between the two devices. This telltale gauge is an indicator that shows when the disc ruptures. The failure can be the result of a pressure excursion or of a pinhole caused by corrosion. In either case the telltale gauge indicates that the disc needs to be replaced. 

Rupture Disc and Spring Loaded Relief. Normal Relief May Co Through Spring Loaded Device/ and Rupture Disc Is Back-up for Larger Reliefs. 

The relief vent area calculation depends on the type of flow (liquid, vapor, or two-phase) and the type of relief device (spring or rupture disc). 

Rupture disc Prevents system from exceeding specified overpressure. Effectiveness of this device can be sensitive to service and experience. 1 x 10 to 1 x 10 5 1 x 10 2... 

For relief-protection dump valves, relief valves, and finally rupture discs are used. The sizing of the relief devices is based on the rate of pressure-rise. The flow area should be large enough to stop the pressure rise as soon as the set pressure is reached. 

Deviations from the set points, and possible malfunctions, must be guarded against by proper precautions such as controls, shut-off valves, shut-down devices, safety valves, rupture discs, etc. 

The most commonly used pressure relief devices in the industry are 1. Rupture discs (non-reclosing devices)... 

While the bursting discs are by far the most commonly used non-reclosing pressure safety devices, (buckling) pin valves can also be found in applications where the operation is closer to the device s opening pressure (found on rupture discs) (Figure 5.48). 

Provided that the appropriate regulations allow this, a single rupture disc can be used on its own for system protection. Rupture discs can be used for both primary relief and as an additional secondary rdief in combination with another pressure rdief device... 

No risk if product is lost after a pressure upset Rupture discs are nonreclosing devices. Whatever is in the system will get out and continue to do so until it is stopped by some form of intervention. If loss of contents is not an issue and it is installed as such, that action can be prompted. 

High-viscosity liquids If the system is filled with highly viscous liquids such as polymers, the rupture disc can be considered because the SRV will have to be equipped with steam jackets, which will increase the price of the device considerably. 

When combining two relief devices, they can be used after each other or in parallel. When used in parallel, for whatever reason, there is no need for a derating. However, the rated relieving capacity of an SRV in combination with a rupture disc is equal to the capacity of the PRV multiplied by a combination capacity factor to account for any flow losses attributed to the rupture disc which might depend on the type of installation. 

A rupture disc is a simple device that essentially consists of a thin material held in place between two flanges. The disc is usually made of metal, although it may be made of other materials. The choice of material is important because the rupture disc must be designed to close tolerances to operate properly. During emergency venting, the disc ruptures when the pressure level rises to a chosen level. The vessel is then vented and the pressure in the vessel eventually drops... 

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