The Double Block and Bleed design features every technical
advantage which the series TRI-CON has plus there is a true
double block and bleed feature which delivers maximum
sealing performance.³ By using this design, the former two
valve system with a spool piece becomes obsolete. This fact
is not only important for installation since you have to install
only one valve body in the pipeline, but also only one actuator
or gearbox is required.4
With Zwick’s unique design of the linkage between the two
shafts, the user is able to actuate both shafts with only one
actuator and reach maximum leak protection with the two
available sealing surfaces.³ The design of the linkage forgives
any dimensional changes due to thermal differences in the
valve.4
The redundant sealing design of this valve is the ideal valve
solution for several critical processes where high-level sealing
and pipe inspection via the bleed port are required.³
Applications like multi-product manifolds, meter stations,
tank storage isolation or hydrant isolation are very sensitive
to leakage and the Double Block and Bleed design would be
an ideal fit.³

3 Leckrate A – C for DIN EN 12266-1 or Zero Leakage for API 598
4 The use of the linkage depends on the process data and must be checked on
request..