In the 1940’s and 50’s, rupture disk designs were limited to disks that could be subjected to normal system operating pressures up to 70% or 80% of stamped burst pressure with good service life. In the 1960’s, the “reverse buckling knifeblade” design was introduced. This design, for use in gas/vapor service only, could be operated up to 90% of stamped burst pressure with good service life. However, if the knifeblades become dull or corroded, or if there was any damage to the dome of the rupture disk, the disk may reverse and lay against the knifeblade without opening. This recently occurred at a Texas petrochemical plant to a disk that was rated at 30 psig. After reversing and not opening, system pressure continued to rise. Fortunately, alert operators shut down the system before the vessel integrity was lost. The disk assembly was removed and placed on a test stand where air pressure was applied. The 30 psig disk finally opened at 292 psig! Because of the dangers inherent with knifeblade assemblies, most safety conscious users of rupture disks prohibit their use in their facilities.

New technology now available eliminates the need for the dangerous knifeblades. Scored disk technology allows both reverse buckling disks (gas/vapor service only) to be manufactured without need of knifeblades. The Forward Acting Scored disk is completely failsafe (even if damaged or incorrectly installed, disk will always open at or below stamped burst pressure). State of the art laser technology even allow high performance, gas and full liquid disks to be manufactured with set pressures as low as 2 psig!

Retrofit of knifeblade designs with newer technologies is simple, even if installed in systems with fixed dimensional piping. New holders can be machined with the identical face to face dimensions as the disk holder being replaced, eliminating the need for expensive and time consuming piping changes.

Contact TEMPRESCO to find out how easy and economical it can be to change out your obsolete rupture disk technology with new, state of the art rupture disks.