Standards Australia - Australian Standard Bursting disks and bursting disk devices - Guide to application, selection and installation

Section 1. Scope and General

1.1 Scope

This Standard provides guidance on the application, selection and installation of bursting disks and bursting disk devices.

Information which the purchaser may provide to assist in the design or the selection of bursting disks and bursting disk devices is shown in Appendix A.

The information which may be used for identification and also that which may be marked on bursting disks and bursting disk devices is shown in Appendix B.

Equations for the calculation of the discharge capacity for single phase flow are shown in Appendix C.

1.2 Definitions

For the purpose of this Standard, the definitions below apply.

1.2.1 Bursting pressure - the value of the pressure differential across the disk at which a bursting disk device functions. (See Note to Clause 1.2.2.)

1.2.2 Specified bursting pressure - the pressure, quoted with a coincident temperature, specified by the user or his agent when defining the disk requirement.

NOTE: The words maximum and minimum may be used with the terms bursting pressure and specified bursting pressure

1.2.3 Average bursting pressure - the arithmetic average value, at the coincident temperature, of the test bursts carried out on a batch of disks.

1.2.4 Coincident temperature (bursting pressure) - the temperature used in conjunction with bursting pressure.

1.2.5 Operating temperature - the average temperature of the disk and the surrounding parts during normal operation.

1.2.6 Bursting tolerance - the maximum variation of test results in equal positive and negative quantities or percentages related to the average bursting pressure. Where a zero manufacturing range is stated, the tolerance is applied directly to the specified bursting pressure.

1.2.7 Manufacturing range - a range of pressure within which the average bursting pressure of a batch of bursting disks falls in order to be acceptable for a particular application.

1.2.8 Performance tolerance - a range of pressure in positive and negative quantities or percentages which includes both manufacturing range and bursting tolerance at a coincident temperature, which is applied directly to the specified bursting pressure.

1.2.9 Foil - the sheet or strip used for the manufacture of metallic bursting disks.

1.2.10 Batch - a group of bursting disks of the same type, size, average bursting pressure, and coincident temperature, manufactured from material of the same identity and properties made as a single group.

1.2.11 Bursting disk device - a non-reclosing pressure-relief device actuated by differential pressure and designed to function by the bursting or venting of the bursting disk.

1.2.12 Bursting disk assembly - the complete assembly of components which are installed in the bursting disk holder to perform the desired function.

1.2.13 Bursting disk - the pressure-containing and pressure-sensitive element of a bursting disk device.

1.2.14 Bursting disk holder - that part of a bursting disk device which retains the bursting disk assembly in position.

1.2.15 Backpressure - the static pressure existing at the outlet of a bursting disk device at the time the device is required to operate. It is the result of pressure in the discharge system from other sources or as a result of vacuum on the upstream side.

1.2.16 Backpressure support - that component of a bursting disk assembly which prevents the failure of the disk due to backpressure differential.

NOTE: A backpressure support which is intended to prevent the failure of the disk when the system pressure falls below atmospheric pressure is sometimes referred to as a vacuum support.

1.2.17 Baffle plate - a plate attached to vent side of a bursting disk device or system to redirect discharge or redirect discharge or reduce recoil.

1.2.18 Muffled outlet - a component of a bursting disk device which disperses the discharge.

1.2.19 Stiffening ring - an integral component of the bursting disk assembly used primarily for the stiffening of fragile disks.

1.2.20 Coating - a layer of metallic or non-metallic material applied by brush, spray, dipping, fluidised bed, or other similar method to components of a bursting disk device.

1.2.21 Lining - an additional sheet or sheets of material forming part of the bursting disk assembly or holder. The lining can be metallic or non-metallic.

1.2.22 Plating - a metal layer applied to a disk or holder by a plating process.

1.2.23 Excess flow valve - a device which permits limited flow. When this flow is exceeded the valve closes.

1.2.24 Conventional domed bursting disk - a bursting disk which is domed in the direction of the bursting pressure and designed to fail in tension. (See Figures 2.2 and 2.3).

1.2.25 Slotted lined bursting disk - a conventional domed bursting disk made up of two or more layers, one of which is slit or slotted so as to reduce its strength and to control the bursting pressure of the bursting disk. (See Figure 2.4).

1.2.26 Reverse domed bursting disk - a bursting disk which is domed against the direction of the bursting pressure and designed to fail by buckling, bending or shearing forces. (See Figure 2.5).

1.2.27 Graphite bursting disk - a bursting disk manufactured in graphite and designed to fail by bending or shearing forces.

1.2.28 Temperature shield - a device which protects a bursting disk from excessive temperature.

1.2.29 Bursting disk device discharge area - the area which is the geometric minimum cross-sectional flow area of the bursting disk device which is used to calculate the theoretical flow capacity of the bursting disk device.

NOTE: Possible reduction of the cross-section, for example by backpressure supports, catching devices, or parts of the bursting disk which remain after bursting, has to be considered.

1.2.30 Bursting disk device discharge capacity - the rate at which a bursting disk device can discharge fluid after bursting or venting of the bursting disk.

1.2.31 Service life - the time period beginning at the installation of a bursting disk assembly and ending at either replacement or burst.

1.2.32 Operating pressure - the pressure to which the bursting disk is exposed during normal operation.

1.2.33 Inspecting Authority - the Authority having statutory powers to control the design, manufacture, and use of bursting disks and bursting disk devices in the State or Territory in which they are to be used except that where the devices are not subject to such statutory jurisdiction the Inspecting Authority is the purchaser, or the person or organisation named as such in the purchase order.

1.2.34 Inspector - either the Inspecting Authority or a person or an organisation appointed or approved by the Inspecting Authority for the purpose of inspecting bursting disks and bursting disk devices in accordance with this Standard, except that in regard to materials ‘Inspector’ be a person acting under the express written authority of the purchaser of the material.

1.2.35 Approved and approval - approved by or with the approval of the Inspecting Authority.

1.2.36 Shall - indicates that a statement is mandatory.

1.2.37 Should - indicates a recommendation.