Non-Return Dampers / Gravity Louvers
Introduction
ALUGRIDX Non-Return Dampers are also known as Gravity Dampers, Back Draught Dampers, and Pressure Relief Dampers.
In addition, these non-return dampers operate automatically via airflow to open or close during intake, discharge, and pressure-relief cycles across air-conditioning systems. Furthermore, we engineer every unit with robust mechanical specifications for long-term reliability:
• Heavy-Duty Frame: We manufacture the outer frame from high-grade aluminum or $1.1\text{ mm}$ thick galvanized sheet steel.
• Precision Blades: Our team fabricates durable blades from $0.5\text{ mm}$ or $0.7\text{ mm}$ aluminum sheets.
• Quiet Operation: We fit the blades with nylon bushes to deliver smooth, rattle-free rotation.
• Rigid Stability: Galvanized steel rods secure the nylon bushes to the main assembly, ensuring stable performance under variable air pressure.
• Blade Control: An internal aluminum or steel stop angle prevents excessive blade travel.
• Center Support: We include an additional center partition whenever the length or height exceeds $900\text{ mm}$.
Available Standard Sizes
| L | 150 | 200 | 300 | 400 | 500 | 600 | 700 | 800 | 900 | 1000 |
|---|---|---|---|---|---|---|---|---|---|---|
| W | 150 | 200 | 300 | 400 | 500 | 600 | 700 | 800 | 900 | 1000 |
MODEL GL-RC-E
A Gravity Louver / Back Draught Damper for the installation on the External face of the wall.
MODEL GL-RC-E
A Gravity Louver / Back Draught Damper for the installation on the External face of the wall.
MODEL GL-RC-E
A Gravity Louver / Back Draught Damper for the installation on the Internal face of the wall.
MODEL NRD-RC-F
A Flanged-Type Duct mounted Non-Return Damper.
The outer frame is manufactured from galvanized sheet steel of 1.2 mm thickness.
The blades are manufactured from aluminum sheet of 0.5 mm / 0.7 mm thickness in mill finish and are fixed to the main frame by means of galvanized steel rod of 2 mm / 3 mm dia.
MODEL NRD-RC-S
A Straight-End Duct mounted Non-Return Damper.
The outer frame is manufactured from galvanized sheet steel of 1.2 mm thickness.
The blades are manufactured from aluminum sheet of 0.5 mm / 0.7 mm thickness in mill finish and are fixed to the main frame by means of galvanized steel rod of 2 mm / 3 mm dia.
Performance Data
NOMENCLATURE
Pt (Pa)………………………….Pressure Drop
Vf (m/sec)…………………….Air Velocity based on nominal size.
                   (free discharge)
| MODEL | TYPES |
|---|---|
| GL-RC-E | Gravity Louvers for External Wall Mounting |
| GL-C | Gravity Louvers with Round Neck |
| GL-RC-I | Gravity Louvers for Internal Wall Mounting |
| NRD-RC-F | Non-Return Damper Flange Type for Duct Mounting |
| NRD-RC-S | Non-Return Damper with Straight Ends for Duct Mounting |
Ordering Procedures
Ordering Data
Available Finish
Powder Coated color finish
Natural Anodized Aluminum
Mill finish Aluminum
Galvanized sheet steel frame for duct-mounted type and Round neck type
Type of Fixing
Countersunk screw fixing suffix ‘S’ (standard supply)
(recommended for side wall applications)
Spring clip concealed fixing suffix ‘C’