Main Seat Leakage

Main seat leakage has affected various SRVs but has been a reoccurring issue for the Target Rock vertical discharge valve. The valve design greatly affects what seat leak initiators are likely to affect main seat performance. The Target Rock, pilot operated, vertical discharge valve has suffered from various seat leak initiators including cracks in the hard-facing material and thermal distortions in the contact pressure band.

Figure 1: Corrosion and Steam Cuts on the a) main seat and b) main disc

a) Steam Cut on Main Seat
b) Steam Cut on Main Disc
Figure 1: Corrosion and Steam Cuts on the a) main seat and b) main disc