Requirements for dust content of compressed air produced by air compressor

The dust content requirements for compressed air vary according to industries and application scenarios. The following are detailed from three aspects: standards, testing methods and industry differences:

1. Dust content standards and levels

1. general standard

• ISO 8573-1: International general standard divides the dust content of compressed air into 4 levels:
• Class 1: ≤0.1 mg/m³ (high purity clarity, suitable for semiconductors and pharmaceuticals)
• Class 2: ≤1 mg/m³ (precision manufacturing, pneumatic instrument)
• Class 3: ≤5 mg/m³ (general industrial gas)
• Class 4: ≤10 mg/m³ (non-critical application scenarios)
• GB/T 13277: China national standard, compatible with the ISO system, additionally stipulates that the dust particle size must be ≤5μm.

2. Particulate matter restriction

• Particle size requirements: Critical equipment (such as pneumatic valves, bearings) requires particulate matter ≤3μm to avoid clogging or wear.

2. Dust content detection method

1. on-line monitoring

• dust particle counter: Real-time detection of particulate matter concentration of 0.1-5μm, with an accuracy of 0.001 mg/m³.
• optical sensor: Analyze dust content through scattered light intensity, suitable for use in high humidity environments.

2. laboratory testing

• membrane weighing method: Collect compressed air to filter membrane, weigh dust mass, accuracy 0.1 mg/m³.
• microscopic observation: Analyze the composition and shape of particulate matter on the filter membrane (metal chips, fibers, etc.).

3. on-site rapid detection

• compressed air test board: Observe the residue after blowing for 30 seconds and qualitatively judge the dust content.
• portable detection instrument: Combine infrared sensor and laser scattering technology to display dust content in real time.

3. Specific requirements of the industry

1. precision manufacturing

• electronics/semiconductor: Dust content ≤0.1 mg/m³, particle size ≤0.1μm, to avoid contaminating the wafer.
• pharmaceutical packaging: It must meet ISO Class 1 standards and be equipped with a sterilization filter.

2. general industrial

• pneumatic tools: Dust content ≤5 mg/m³ to prevent nozzle clogging.
• Spraying industry: Additional requirements for oil content ≤0.1 mg/m³ to avoid paint defects.

3. special environment

• food packaging: Dust content ≤1 mg/m³, complying with HACCP certification requirements.
• textile and chemical fiber: Dust content ≤1 mg/m³, particle size ≤3μm to prevent cloth surface pollution.

4. Control measures

1. Front-end filtering

• Three-stage filtration system: Coarse effect + medium effect + high efficiency filter, the efficiency reaches 99.99%.
• self-cleaning filter: Automatic back blowing cleaning, suitable for high-dust environments.

2. regular maintenance

• replacement cycle: High-efficiency filters are replaced every 2000 hours, and crude filters are inspected monthly.
• pipe cleaning: Annual purging to prevent rust from falling off.

3. monitoring plan

• daily testing: Use a portable detector to randomly check key gas consumption points every day.
• annual audit: Entrust a third-party laboratory to conduct all tests and issue a compliance report.

By strictly implementing dust content standards, reasonably selecting testing methods and implementing system maintenance, compressed air can be ensured to meet the process needs of various industries, extend equipment life and improve product quality.