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Calculation of safety valves with LESER-Valvestar

VALVESTAR® - Sizing of your LESER Safety Valves

VALVESTAR® is the LESER-developed program for sizing safety valves. It takes into account all leading global standards and codes. In addition to calculation and sizing, the program also offers variable, individually-arranged reports for technical documentation and archiving. More than 5000 users are already using either VALVESTAR® or VALVESTAR®-Web.

If you have questions please contact:

Andreas Caldonazzi
E-Mail: valvestar@leser.com

Program Highlights


  • Sizing of safety valves in accordance with the leading global standards and codes (i.e. API 520, ASME Sec. VIII Div. 1, ISO 4126-7, AD 2000-Merkblatt A2)
  • Calculates two-phase flow in accordance with API 520 Appendix C and fire case according to API 521
  • Calculates inlet pressure loss, back pressure, reaction forces, and noise level


  • Various types of documents are selectable (i.e. project reports, single-page reports, and ISA data sheets) 
  • Customizable report layouts (customer logo, address, etc.) 
  • Exportable in different data formats (i.e. XLS, HTML, PDF, etc.)
  • Integrated parts lists and sectional drawings of all LESER safety valves


  • User-friendly wizard function leads you step by step through the sizing process
  • Microsoft.Net architecture offers the most modern graphical user interface for simple operation and better performance


  • User-specific profile set-up with pre-selectable units of measure, calculation methods, and more
  • More than 15 selectable languages

Use Valvestar®

The following options are available to you:

Web-based use of VALVESTAR® without need of administrative rights

Download VALVESTAR® 7.3.3_0331 as a program (approx. 150 MB)

Update your version to VALVESTAR® 7.3.3_0331 (approx. 17 MB, requires min. 7.3.1)
Get a detailed description of the program VALVESTAR® - PDF

LESER Safety valves

Safety Valve Knowledge 

Learn more about safety valves in our basic knowledge section.

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