NKTMJ Non-Return/Backdraft Damper

Categories Special Applications, Special Applications - MANDK

NKTMJ Non-Return/Backdraft Damper

A heavy-duty mechanical backdraft damper designed for extreme conditions, featuring seismic resistance, 7500 Pa pressure rating, and 40-year service life. It automatically closes against reverse airflow to maintain system integrity and safety in critical ventilation applications.

Product Description

Key Features & Benefits

Automatic Reverse Flow Protection
Closes automatically on reverse airflow to prevent backdraft and contamination.
Seismic & High Pressure Rated
Withstands 7500 Pa pressure and high-level seismic events with external mechanism.
40-Year Service Life
Guaranteed longevity with 10,000-hour maintenance intervals and plain bearings.
High Velocity & Low Leakage
Handles 25 m/s airflow with ≤2% leakage when closed for energy efficiency.
Adjustable Counterweight System
Optional counterweight allows precise adjustment for different pressure conditions.
Radiation & Decontamination Ready
Resists radioactive aerosols and is designed for decontamination in nuclear facilities.

Technical Specifications

Dimensions

Min: 200×200×210 mm. Max: 2000×2000×210 mm. Square (round adapter available).

Design & Construction

Type: Mechanical only. Casing: 3mm steel (painted, galvanized, or stainless). Welded.

Performance

Max Airflow: 25 m/s. Max Pressure: 7500 Pa. Leakage: ≤2% when closed.

Special Features

External Mechanism: Mounted outside airflow path. Counterweight: Adjustable option.

Environmental Resistance

Seismic: High resistance. Radiation: Aerosol impact allowed. Life: 40 years.

Maintenance

Interval: 10,000 hours recommended. Bearings: Plain, maintenance-free.

Installation & Integration

Heavy-Duty Mounting

Requires structural support for 7500 Pa pressure; external mechanism for easy access.

Counterweight Adjustment

Optional counterweight system adjustable on-site for specific pressure thresholds.

External Mechanism Design

Mechanism outside duct avoids airflow interference and allows maintenance without shutdown.

Decontamination Ready

Smooth surfaces and sealed design allow cleaning in radioactive/chemical environments.