OsecoElfab Disc Sizer

Coefficient of Discharge Method

Rupture disc sizing built for fast engineering decisions.

Launch gas, liquid, steam, or two-phase calculations with the API 520 Part 1 paragraph 5.11.1.2 discharge approach, then compare disc options and retain calculation history in one place.

Start Gas / Vapor Start Liquid Start Steam Start Two-Phase

Method API 520 Direct atmospheric discharge workflow

Services 4 Gas/vapor, liquid, steam, and two-phase calculators

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Gas / Vapor

For compressible relieving conditions where media properties and back pressure drive the required area.

Sizing Capacity

Liquid

For incompressible flow cases where density, viscosity, and system losses define the relief path.

Sizing Capacity

Steam

For saturated or superheated steam applications that depend on temperature pressure correction data.

Sizing Capacity

Two-Phase

For flashing liquid/vapor mixtures sized using the API 520 Appendix D omega method.

Sizing Capacity

API 520 boundaries

Use this method only when all four installation rules are true.

Atmospheric discharge

The rupture disc device must discharge directly to atmosphere.

Short inlet run

Installation must be within eight pipe diameters from the vessel nozzle entry.

Short discharge length

Discharge piping length cannot exceed five pipe diameters.

Matched pipe sizes

Nominal inlet and outlet piping must match the device nominal pipe size.