Brochure

After the wood chips are sufficiently cooked, they must be discharged from the digester. Digester blow valves, typically found at the
bottom of digesters and/or near the top of the blow tank, ensure pulp stock retains its integrity while still allowing all cooking liquors to
be recovered. However, insufficient discharge can ruin valuable pulp and cause loss of expensive steam and cooking liquors. In batch and
continuous digesters, these valves are subjected to erosion and high vibration from high velocity stock flow.
High levels of sand and other debris from the chip feed stock will also cause premature valve body and ball erosion. Additionally, in batch
digesters, it is critical for the valve to retain its pressure boundary and prevent leakage as this can lead to inefficient cooking of the wood
chips. Precise control is necessary to achieve the required pulp kappa value.
Digester Blow
Product Solutions
Fisher
®
Pulp and Paper Solutions | 13
Cooking
n MAXIMUM FLOW CONTROL V-notch ball contouring provides modied equal percent characteristic for maximum
ow control.
n ZERO LOST MOTION Splined driveshaft ensures zero lost motion allowing for tight control.
n TIGHT SHUTOFF Heavy duty seal provides tight shutoff.
n EASE OF MAINTENANCE Drop-in-place installation for easy maintenance.
n REDUCED MAINTENANCE Flanged valve body design reduces alignment and installation time.
n SMALL ACTUATOR PROFILE Actuator design promotes smaller envelope package size for tight spaces.
n POSITIONER FEEDBACK Linkage-less and non-contact feedback improves reliability in high vibration.
Fisher V150 Vee-Ball control valve, 2052 actuator, and FIELDVUE DVC2000
Cooking