3Section
Dam
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Isolation DamperIntroduction
A range of high integrity dampers has been designed to meet the
requirements of the oil and gas, nuclear and process industries,
where corrosion resistance and mechanical integrity are of prime
importance. The following design features have been included:
Continuously welded construction Opposed blade motion Low casing
leakage Low blade leakage Manual, pneumatic,
or electric operation Wide range of materials
and controls Excellent corrosion resistance
Description
CasingThis is a continuously welded channel section construction
and is available in a range of materials and thickness. Typically:
Stainless steel (1.5 mm to 3.0 mm thick) grade 316L or 304, mild
steel, galvanised after manufacture (3.0 mm or 5.0 mm thick) or
pre-galvanised steel. Angles with closed cell gaskets are tted at
the top and bottom as well as stainless steel grade 316L
(1.4404)precision roll formed sprung side seals in order to achieve
an effective seal between the damper case and the blades.
BladesThese are typically of stainless steel grade 316L/304 or
pre-galvanised steel. They are of double skin aerofoil section.
Blades are riveted to continuous tubular spindles. The spindles
rotate in acetal resin bushes and are linked externally to provide
opposed blade motion.
Control MechanismsManual Isolating Damper: This is operated by a
robust adjusting handle with a locking device which moves across a
quadrant plate. Moving the handle through 90 moves the blades from
the fully open to the fully closed position, thereby enabling the
unit to be used for volume control purposes if necessary.
Pneumatic and Electric Isolating Dampers: These are operated by
actuators which move the blades from fully open to fully
closed.
The actuator is controlled by either a pneumatic or electric
signal. Micro-switches indicating blade position are also
available. These units are designed to be fully open or fully
closed. If intermediate blade positions are required a modulating
control damper should be incorporated in the system.
Control OptionsRefer to details in the Controls Section.
OptionsThe following options can be incorporated if required.
Oil impregnated sintered bronze bearings in place of acetal.
Reduced cost riveted/welded/sealed construction.Heavy duty 1.5 mm
double skin blades welded to continuous solid shafts.Core depth:
200-300mm Bearing Lifting lugs Earth bosses Client specic
requirements
Modications to meet specic client specications eg. BNF Plc
NF.
Dam
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3Section
Leakage Rates
Isolation damper are designed to minimise leakage. Extensive
testing on standard production single module dampers (max
1200x1200mm) has proven a maximum leakage rate of 0.060 m/sec/m at
a differential pressure of 2000Pa and 0.010 m/sec/m at a
differential pressure of 50Pa. However, if lower leakage rates are
required as a special requirement, please consult our engineering
department.
Damper leakage meets the requirements of EN 1751 Class 2. The
leakage rate on multi-module dampers will be higher, 0.080 m/sec/m
at 2000Pa for a 2 module damper and 0.100 m/sec/m at 2000Pa for a 4
module damper.
Damper leakage rates meets the requirements of EN 1751 Class 3
are available on request.
Ordering
Quantities, surface nish and other special requirements to be
stated separately.
Type MID Duct Width 300W
Material 316L Duct Height 300H
Case Thickness 3.0 Case Depth 300D
Type Wozair: Manual Isolation Damper
Damper Types: MID = Manual Isolation DamperPID = Pneumatic
Isolation DamperEID = Electric Isolation Damper
Case Material: Stainless Steel Low Carbon 1.4307 (SS304L) = 304L
Low Carbon 1.4404 (SS316L) = 316L Mo>2.5% 1.4432 (SS316L) =
316L
Mild Steel Sheet Pre-Galvanised FeP02 nac = GSS Galvanised after
Manufacture = GAM
Case Thickness: 1.5-5 mm see description
Nominal Clear inside duct dimensions Duct Size: Quote (Width x
Height)
Order Code Example: MID/316L/2.0/300W/300H/300D
Section 3.16Section 3.17
