Predklapan

Selecting safety relief valves is a critical task for the safe operation of high-hazard industrial facilities.

Under GOST 12.2.085-2017, the software determines required properties of the discharged medium (density, viscosity, adiabatic exponent and other parameters) from the specified composition, for both single-phase and gas-liquid mixtures;

calculates the required valve flow area and discharge capacity under GOST 12.2.085-2017, including by the Homogeneous Direct Integration method of a homogeneous equilibrium flow model, which covers various two-phase gas-liquid releases and flashing or condensation inside the valve;

determines the minimum permissible nominal valve pressure;

selects valve types and quantities from a database (including assemblies with changeover devices) and offers different installation arrangements;

selects springs, design variants or the weight and number of counterweights;

calculates downstream temperatures and gas fractions accounting for throttling effects;

calculates pressure, temperature and gas fraction at the valve seat in critical-flow conditions;

sizes connected piping or verifies user-specified pipe diameters;

performs hydraulic analysis of connected piping and verifies that pressure losses are acceptable;

automatically produces project documents: equipment schedules, specifications and detailed calculation reports for relief valves and piping.

Databases

The software database includes safety relief valves and safety-device assemblies from well-known Russian manufacturers of industrial protective valves, including Blagoveshchensk Valve Plant and Armagus. The developer regularly updates it as manufacturers change their product ranges, and users can add their own data.

A built-in report generator prints input data and calculation results, offers print previews, and saves reports in various formats for inclusion in other documents. Reports follow SPDS documentation standards, and users can customize their format (such as changing title blocks or adding a company logo) through the built-in template editor.

Interface

Well-organized dialog input and context-sensitive help available at any time make the software quick to learn without special training. The algorithm is described in detail in the User Guide, which also explains the meaning and relationships of key concepts used to calculate and select safety relief valves.

Configuration

Predklapan provides extensive functionality for automatic calculation of the discharged medium's thermophysical properties and phase equilibria. The following modules are built in:

the STARS library calculates thermophysical properties of pure substances, petroleum fractions and their mixtures in liquid and gas phases. Its database contains more than 1600 substances. STARS automatically calculates phase equilibria and checks the medium's physical state;

the WaterSteamPro module calculates refined thermophysical properties of water and steam under the international IAPWS-IF97 methodology, improving accuracy for water and steam piping (recommended by RAO UES for use in the power industry);

an optional separately licensed thermodynamic library, Simulis Thermodynamics by ProSim, can be connected.