PR-L ATEX GAS and DUST – explosion-proof backward-curved centrifugal fans for slightly dusty explosive gas atmospheres ≤140000 m³/h

PR-L ATEX GAS and DUST – explosion-proof backward-curved centrifugal fans

DYNAIR / MAICO ITALIA PR-L ATEX centrifugal fans are intended for conveying clean or slightly dusty air in potentially explosive flammable gas or dust atmospheres. They comply with ATEX Directive 2014/34/EU and are suitable for Zones 1 and 21, equipment categories II 2G and II 2D respectively. The series provides airflow from 2500 to 140000 m³/h, with fan diameters from 250 to 1400 mm.

Main features

• ATEX explosion-protected construction for flammable gas and dust atmospheres, Zones 1 and 21
• ATEX equipment categories II 2G and II 2D
• designed for clean or slightly dusty air
• high airflow rates at medium or low pressure
• airflow range from 2500 to 140000 m³/h
• fan diameters from 250 to 1400 mm
• operating temperature from -20 °C to +40 °C
• volute casing manufactured from sheet steel with epoxy-polyester powder coating
• wide-radius inlet cone with brass coating
• single-inlet steel impeller with backward-curved blades and high aerodynamic efficiency
• impeller protected by epoxy-polyester powder coating
• Class III high-speed impeller versions available
• direct-drive arrangement 4
• belt-driven arrangements 1, 9 and 12
• belt-driven versions with cast-iron monobloc bearing support and lubricable ball bearings
• belt drive components include pulleys, belts, motor support and belt guard
• three-phase asynchronous electric motors, IP55 protection and insulation class F
• continuous duty S1
• left-hand LG and right-hand RD discharge orientations available
• standard catalogue discharge orientation LG270°

Fan casing orientations

Available LG0°, LG45°, LG90°, LG135°, LG180°, LG225°, LG270° and LG315° positions, together with the corresponding RD orientations. Standard catalogue arrangement: LG270°.

Drive arrangements

• arrangement 4 – impeller directly coupled to the electric motor
• arrangement 1 – independent bearing support and belt transmission system
• arrangements 9 and 12 – alternative belt-drive configurations

Optional accessories

• inlet counter-flange
• outlet counter-flange
• inlet protection guard
• outlet protection guard
• inlet flexible connector
• outlet flexible connector

PR-L, PR-L INOX and PR-L AT are separate product versions. Their higher-temperature or corrosion-resistant specifications do not automatically apply to PR-L ATEX.

PR-L ATEX – technical catalogue (PDF)

PR-L ATEX GAS and DUST – dimensions

Dimensions are in millimetres (mm). The table shows the main casing dimensions shared by models of the same size in arrangement 4. Motor-dependent and arrangement-specific dimensions are given in the manufacturer's drawings.

Arrangement 4 – sizes 250–500

Arrangement 4 – sizes 560–1400

Main dimensions for arrangement 4

Arrangement 1 – sizes 250–500

Arrangement 1 – sizes 560–1400

Inlet connection dimensions

Complete arrangement 1 and 4 dimensions, fixing holes, outlet connections and weights are given on catalogue pages 95–99.

PR-L ATEX – original dimensional drawings and tables (PDF)

PR-L ATEX GAS and DUST – technical information

Motor power ranges by fan size

Actual motor power, current, rotational speed and operating point depend on the model and arrangement. The catalogue provides individual motor data and performance curves.

PR-L ATEX – model specifications and performance curves (PDF)

PR-L ATEX GAS and DUST – installation and operating instructions

Application

PR-L ATEX fans are designed to convey clean or slightly dusty air in industrial and air-conditioning systems where potentially explosive flammable gas or dust atmospheres may occur. They are intended for ATEX Zones 1 and 21, equipment categories II 2G and II 2D.

Operating conditions

• conveyed medium temperature from -20 °C to +40 °C
• operate only in accordance with the specific fan's ATEX marking and documentation
• assess the composition and dust content of the conveyed medium before selection
• select the operating point from the manufacturer's performance curves

Mechanical installation

• install on a stable support suitable for the equipment weight and operating loads
• ensure ductwork does not deform the fan casing
• check mechanical clearances and free impeller rotation
• provide secure inlet and outlet connections
• allow adequate access for maintenance
• on belt-driven versions, check belt tension, pulley alignment and guards

Casing orientation

The standard catalogue discharge orientation is LG270°. The selected orientation and rotation direction must match the fan drawing, order specification and duct arrangement.

Electrical connection

• electrical work must be carried out by qualified personnel
• follow the motor rating plate and ATEX documentation
• provide protective earthing and electrical continuity in accordance with manufacturer requirements
• install suitable motor protection
• use only electrical components and connection methods approved for the relevant ATEX conditions

Commissioning

• verify impeller rotation direction
• inspect fan mountings and duct connections
• ensure the impeller does not contact the casing
• check vibration, noise and bearing condition
• measure motor current and compare it with rated data
• verify the operating point against the manufacturer's performance curves

Maintenance

Regularly inspect the casing, impeller, bearings, fasteners, motor and electrical connections. Remove dust deposits and monitor changes in vibration. For belt-driven versions also inspect belts, pulleys, bearing lubrication and guards. Before maintenance, isolate the electrical supply, prevent accidental restarting and comply with ATEX safety requirements.

PR-L ATEX – manufacturer's technical catalogue (PDF)