These types of dampers are mainly used for isolation of equipment to permit inspection, maintenance or repair in addition to process isolation. They are generally rack-pinion screw or chain type. Screw type design is available in rising or non-rising movement. Where available space is constraint than non-rising design is recommended.

These types of dampers are mainly used for isolation of equipment to permit inspection, maintenance or repair in addition to process isolation. They are generally rack-pinion screw or chain type. Screw type design is available in rising or non-rising movement. Where available space is constraint than non-rising design is recommended.