Bi-Directional Rupture Disc ZW

The bi-directional rupture disc opens in one direction for a defined overpressure and in the other direction for vacuum. It is primarily used in storage tanks and processes involving gases or liquids. The rupture disc permits a standard operating ratio of 80%* in the overpressure direction and 70%* in the vacuum direction. The bi-directional rupture disc can be supplied with an integrated SNR signaling unit. When the disc ruptures in either the overpressure or vacuum direction, the SNR gives an open circuit signal to advise of an activation.

By combining the principles of the KUB® reverse acting rupture disc with the buckling pin and the triple-section design of the ODV forward acting rupture disc, we can offer you a rupture disc that responds at two different but precisely defined burst pressures.

* Depending on the specific application.



  • Chemical reactors
  • Power plants
  • Oil and gas separation and treatment
  • Petrochemical plants
  • Process vessels
  • Refineries
  • Silos


  • Breweries
  • Chemical – petrochemical
  • Food
  • Oil and gas industry
  • Pharmaceutical industry


  • Performs the work of two rupture discs at one installation point.
  • No additional holder required: mounted directly between flanges or angular rings.
  • Suitable for a wide range of applications