VOCON MAST RISER SYSTEM

A VOCON mast riser system serves to reduce the effect of standard p/v valves yielding 50% or more blow-down (difference between opening and re-setting pressure). However, this is not relevant when SCANJET tank level valves are installed as they have no blow-down when thermal venting takes place.

In contrast, a VOCON mast riser system will reduce the operative pressure, thus, increase the VOC loss compared to leaving the SCANJET high-velocity valves with the dual nozzle system to take care of thermal venting during voyage.

Therefore, a VOCON mast riser system is not needed when in combination with SCANJET dual nozzle valves, but quite necessary if standard p/v valves are used.

To discuss your valves requirements for your vessel, then please contact us for more information.