the preventive measures for ultrasonic flowmeter zero drift

Here is the professional English translation of the preventive measures for ultrasonic flowmeter zero drift:

I. Installation & Environmental Control?

Stable Temperature Environment?

Maintain operating temperature within ?-30°C to 160°C?. Beyond this range, install temperature sensors for automatic acoustic velocity compensation ?.

Avoid direct sunlight on probes; add thermal insulation to pipe exteriors ?.

Vibration Suppression?

Install flowmeter ≥20D (D=pipe diameter) from pumps/valves; reinforce pipe supports ?.

Use elastic gaskets to isolate high-frequency vibration sources (e.g., compressors) ?.

II. Operational Maintenance?

Periodic Zero Adjustment?

Manual Zeroing?: With static full-pipe flow, execute zeroing via device menu (e.g., M42) if instantaneous flow ≠ 0 ?.

Automatic Calibration?: Enable weekly self-check for zero validation under no-flow conditions ?.

Low-Flow Cutoff Setting?

Set threshold to ?0.03–0.05 m/s? to filter false micro-flow signals ?.

Sensor Maintenance?

Clean probe surfaces quarterly; replenish couplant semi-annually (ensure >95% acoustic transmission) ?.

Inspect cable shielding integrity to prevent EMI-induced signal distortion ?.

III. Fluid & Parameter Management?

Medium Stability Monitoring?

Switch to Doppler mode and recalibrate if bubble content >0.1% or suspended solids fluctuate abruptly ?.

Manually input real-time density data if fluctuations exceed ?±5%? to correct acoustic models ?.

Dynamic Damping Adjustment?

Increase damping coefficient to ?3–5 seconds? in turbulent zones (e.g., downstream of pumps); reduce to ?1–2 seconds? for steady flows ?.

IV. Calibration & Upgrade Strategies?

Scenario? ?Action? ?Frequency?

Custody transfer (0.5-class) Factory recalibration + field verification Mandatory 1 year ?

High-temp/corrosive media Upgrade corrosion-resistant probes + acoustic model 2 years ?

Aging devices (>5 years) Capacitor testing + zero-drift module retrofit As needed ?

Key Notes?:

Perform initial zeroing after 72 hours of new device operation to eliminate stress deformation ?.

Always verify static zero before restarting long-idle equipment ?.

This integrated approach (temperature control, dynamic zeroing, fluid adaptation, and calibration) reduces zero-drift risk by ?>80%? ?.

(Translation retains original technical terminology, citation markers, and logical structure for accuracy. Units/metrics standardized to SI format.)