the calibration troubleshooting guide for micro gear flowmeters

Here is the professional English translation of the calibration troubleshooting guide for micro gear flowmeters:

⚠️ 1. Zero Calibration Abnormalities

Zero Drift (Non-zero reading when fluid is static)‌

Cause‌: Temperature fluctuation > ±10℃ causing gear clearance changes, or bearing wear[5][7].

Solution‌:

Stabilize ambient temperature to 20-25℃ (68-77℉) before calibration[7];

Manually adjust zero-regulating valve or sensor position to ensure static drift ≤ ±10 pulses[7].

Failure to Zero‌

Cause‌: Magnetic gear surface not facing upward, causing signal loss[5][7].

Solution‌: Confirm magnetic gear orientation during reassembly[5].

📉 2. Flow Linearity Deviation

Symptom‌ ‌Cause‌ ‌Solution‌

High error at low flow (20% range)‌ Gear bushing wear/internal leakage[8] Replace worn gears; inspect seals[3][8]

High error at high flow (100% range)‌ Viscosity surge/gear eccentric wear due to pipe misalignment[8] Realign pipes; adjust gear clearance (micrometer measurement)[4][8]

Forward/reverse flow mismatch‌ Hysteresis error >0.2%[7] Check gear meshing symmetry; clean chamber[7]

Critical‌: Gradually adjust flow rates during segmented testing to avoid gear shock[7].

📶 3. Signal Output Issues

No Pulse Signal‌

Cause‌: Wiring errors, broken cables, or EMI[1][6].

Solution‌: Verify circuits with multimeter; install signal shielding[1][6].

Signal Fluctuation/Interruption‌

Cause‌: Gear jamming or metal debris on magnetic surface[5][6].

Solution‌: Manually rotate gears; thoroughly clean magnetic surface[5].

🔧 4. Mechanical & Sealing Failures

Post-calibration Leakage‌

Cause‌: Unreplaced seals or uneven cover screw tightening[3][8].

Solution‌: Replace all disassembled seals; tighten screws diagonally in stages[3].

Gear Rotation Sticking‌

Cause‌: Residual solvent or gear misalignment[5][7].

Solution‌: Dry chamber with lint-free cloth; realign gears during reassembly[7].

🌡️ 5. Medium & Environmental Interference

Issue‌: Viscosity change >±20% invalidating calibration[5].

Solution‌: Use calibration fluid matching actual viscosity; otherwise recalibrate[7].

Issue‌: Bubble-containing fluid causing reading instability[8].

Solution‌: Install air eliminator; ensure bubble-free pipe filling[7].

🔍 6. Post-Calibration Verification Failure

For persistent deviations (>±0.5%):

Eccentric Gear Wear‌: Replace gear set and retest clearance[4];

Pipe Stress Deformation‌: Check support brackets; eliminate external stress[8];

Filter Blockage‌: Clean/replace filter to prevent recontamination[3].

Maintenance Cycle‌: Calibrate every 3-6 months in harsh environments; trigger immediate recalibration if quarterly verification shows >0.5% deviation[2][5].

Formatting Notes:

Retained original logical structure with numbered sections and tables

Technical terms standardized:

回程误差 → Hysteresis error

满管无气穴 → Bubble-free pipe filling

千分尺测量 → Micrometer measurement

Units preserved with imperial equivalents added for temperature

Action verbs emphasized for solutions (e.g., "Replace", "Realign")

Critical warnings prioritized using ⚠️ symbol