Metal laser cutting, plasma cutting, flame cutting, and welding processes are widely used across various industries. For example, laser cutting generates significant dust when rapidly melting metals, including common metals such as iron, copper, zinc, nickel, manganese, aluminum, tin, cadmium, lead, and titanium. Most of these can irritate the eyes, nose, and throat. Some, like cadmium, are known carcinogens. Others, such as lead and manganese, can damage nerves and the brain. Certain metal fume components are also highly detrimental to kidney function. These fumes condense and suspend near the 2-meter height level, directly within the human breathing zone. Prolonged inhalation may cause pulmonary fibrosis, commonly known as welder's pneumoconiosis.

Fully open laser cutting equipment uses an extraction hood principle, employing overhead suction to capture smoke and dust.

Fully enclosed dust extraction is currently the ideal solution for laser cutting and the broader dust control industry. Proper air supply and intake design create stable airflow in enclosed environments, achieving 100% dust capture.

Laser Cutting Smoke Analysis:

a. Smoke particles generated by laser cutting are 0.5 microns and larger, with high concentrations during cutting.

b. Smoke temperatures can reach 80-150°C (near the cutting point), often with sparks and high density.

c. The smoke is fine, lightweight, and prone to irregular dispersion.

Equipment Selection and Design:

a. The dust collector uses specialized HEPA filters with 99.7% efficiency for particles above 0.5μm, designed at a filtration velocity of 1.3 m/min.

b. A pre-filter is installed at the dust collector intake to eliminate sparks generated during laser cutting and prevent fires.

c. The laser cutting table is fully enclosed, maintaining negative pressure at the intake to prevent smoke leakage.

Design Example Calculation:

Laser cutting workspace dimensions: 4.6 × 2.7 × 2.7 m

Infeed opening dimensions under fully enclosed conditions: 2.7 × 1.3 m

Intake area F = 2.7 × 1.3 = 3.51 m²

Target cross-section airflow velocity for smoke extraction: 0.35 m/s

Required airflow rate Q = 0.35 × 3.51 × 3600 = 4400 m³/h

Recommended model: CDX-LT-45 dust collector (4500-5800 m³/h, 2600 Pa total pressure)

Dust Extraction Duct Design:

Based on an airflow rate of 4800 m³/h, the duct must maintain a transport velocity exceeding 15 m/s. A 300 mm diameter duct is selected.