Spectacle blind (obturator) is traditional, but not so comfortable in operation solution: it requires to drain pipeline and disassemble flanges coupling every time
Turning or shifting line blinds enable to reduce operation time dramatically: its require just to loosen and tighten several fixative nuts. Nevertheless, draining of the pipeline is also required
Blind flange valve enables avoid draining – the hole-less body keeps media inside. The operation is very simple: just to remove the cover and put in/pull out the shut-off insert with the tightening cheeks
Fitting-in blind makes to block pipeline possible without depressurization. The shut-off insert maybe fit in and extracted with a special tool
At least, dual expanding plug valve, equipped with gearbox or electric actuator, enables to avoid manual works completely. Special design of the shut-off piece (90° turning wedge with lateral tightening cheeks) grants 100% bi-directional tightness
Comparison table
|
without |
without depressurization |
bi-direction tightness |
double block |
without manual works |
spectacle blind |
|
|
+ |
|
|
line blind |
|
|
+ |
|
|
blind flange valve |
+ |
|
+ |
+ |
|
fitting-in blind |
+ |
+ |
|
+ |
|
dual expanding plug valve |
+ |
+ |
+ |
+ |
+ |