The Coal Powder Sampler is a constant-speed sampling device specifically designed for power plants, thermal power plants, and coal powder boiler pulverizing systems. It is used to obtain uniform and representative coal powder samples from the primary air-coal powder pipeline, to test indicators such as coal fineness, moisture content, and ash content, guiding the optimization of boiler combustion and ensuring the economic and environmentally friendly operation of the unit.
I. Core Working Principle
Comply with the National Standard for Uniform Rate Sampling (GB/T 18511):
The air flow velocity at the gun mouth is kept consistent with the air flow velocity of coal powder inside the pipe, to avoid flow rate deviation causing inaccuracies in sampling of coarse and fine powders; paired with vacuum suction/compressed air blowing, it achieves targeted, full cross-sectional sampling with strong representativeness of the sample.
Section II: Main Categories
By degree of automation
Manual Push-Type Coal Powder Sampler: Manual insertion/extraction of sampling gun, simple structure, low cost, suitable for medium and small-sized units
Semi-automatic Coal Powder Sampler: Electric telescopic sampling gun, reducing manual operation intensity
Fully Automatic Coal Powder Sampler: PLC controlled, automatically performs extension/retraction → isokinetic sampling → blowing → reset, with remote control capability, suitable for large-scale thermal power units
2. By installation and usage method
Fixed: Permanently installed on a single coal powder pipeline for long-term, fixed-point sampling
Portable: Compact, mobile, with multi-channel wheel-mounted inspection and sampling
Armless / Telescopic: During non-operation, the sampling tube retracts from the pipeline airflow, significantly reducing abrasion wear.
III. Core Structure Composition
Sampling Gun / Sampling Probe: Wear-resistant stainless steel material, isokinetic sampling orifice design
Extendable Thrust Mechanism: Electric / Manual, for probe entry and exit from pipes
Vacuum Extraction Components: Water Jet Extractor / Gas Jet Extractor, providing sampling power
Gas and powder separator: Separates coal powder from compressed air, collects samples
Blow-off System: Compressed air blow-off pipes, anti-blocking and anti-dust accumulation
Control Box / Gauge: Differential Pressure Monitoring, Constant Speed Regulation, Stroke Control
IV. Key Performance Features
Constant error ≤ ±5%, sampling results are accurate and reliable
Self-cleaning function, no clogging, no powder accumulation
Full 304 stainless steel material, wear and temperature resistant, suitable for high-temperature coal powder gas flow
Easy installation, flange/tube-style quick connection to pipelines
Fully automatic models allow for unattended operation and timed sampling
V. Applicable Working Conditions and Scenarios
Applicable Medium: Coal Powder + Primary Air Mixture Flow
Common Parameters: Wind Temperature ≤ 350°C, Pressure ≤ 0.25 MPa, Flow Rate 10-30 m/s
Application Scenarios: Direct Blowing Milling System, Intermediate Storage Milling System, Coal Mill Boiler Commissioning and Routine Inspection
Section 6: Key Selection Parameters
Coal powder pipeline nominal diameter DN
Medium Temperature, Working Pressure, Airflow Velocity
Sampling Methods: Manual / Electric / Fully Automatic
Installation Type: Fixed / Portable, Flanged / Welded
Material Requirements: 304/316L Stainless Steel, Wear-Resistant Coating
