81
Damper bodies are supplied in the design made of galvanized plate without any other surface
finishing.
Damper blades are made of fire resistant asbestos free boards made of mineral fibres.
Control devices of dampers has cover from mechanically resistant and standing plastic and rest
of the parts is galvanised without further surface treatment.
Springs are galvanized.
Thermal protective fuses are made of sheet brass, thickness = 0.5 mm.
Fasteners is galvanized. Fasteners is galvanized.
According to the customer's requirements, damper can be made of stainless material.
Specifications for stainless-steel models – classification of stainless steel:
●
Class A2 – Food-grade stainless steel (AISI 304 – EN 17240)
●
Class A4 – Chemistry-grade stainless steel (AISI 316, 316L – EN 17346, 17349)
The respective stainless steel is the material for all components present or accessing the damper
interior; components outside the damper body are typically from galvanised sheet metal
(fasteners for mounting the servo drive or mechanics, mechanics components except Item 4),
frame components.
The following components, including the fasteners, are made from stainless steel at all times:
1) Damper body and all components permanently attached
2) Leaf holders, including pins, metal parts of leaf
3) Control components inside the damper (leaf angle selector, pin with lever)
4) Mechanical components entering the interior of damper body (lower sheet of mechanics,
lock holder “1”, lock lever “2”, lock spring, 8 dia. stopper pin, mechanics pin)
5) Inspection hole cover including the clip and fasteners (if they are parts of the cover)
6) Bearing for torque transfer from the lever with pin on the angle selector at the leaf (made
from AISI 440C)
The leaf of the damper is made from a single piece of homogeneous material Promatect-MST,
thickness 40 mm or is composite from two piece Promatect-H, thickness 20 mm, connected with
galvanised nailed “U” connectors which are sealed with Promat K84 from the outside.
Plastic, rubber and silicon components, sealants, foaming bands, glass-ceramic seals, housings,
brass bearings of the leaf, servo drives, and end switches are identical for all material variants of
the dampers.
The thermal link is identical for all material variants of the dampers. Upon specification by
customer, the thermal link may be made from A4 from stainless steel sheet metal.
The temperature-dependent initiator of the servo drive (sensor) is modified for stainless-steel
variants of the dampers; the standard galvanised screws are replaced with stainless-steel M4
screws of corresponding class the counterpart has stainless-steel riveting M4 nuts.
Some fasteners and components are available in one class of stainless steel; the type will be
used in all stainless-steel variants.
The leaf in the variants for chemical environments (Class A4) is always treated with a coating of
chemically resistant Promat SR.
Any other requirements for the design shall be considered atypical and shall be addressed on an
individual basis.
