HLY-TS-02: CNC Cage Welder Weld Failures, Pitch Drift & Servo Alarm Diagnosis

Fault 1: Cold Welds, Lack of Fusion & Brittle Joint Separation

Root Causes:

1. Low pneumatics (<0.4 MPa) providing inadequate squeeze pressure;
2. Heavy rust scale, drawing oil, or oxidation on rebar surface;
3. Secondary transformer copper flex shunts oxidized; SCR weld cycle too short.

Corrective Actions:

1. Set pneumatic regulator to 0.6 MPa;
2. Use clean, shot-blasted ribbed rebar coils;
3. Polish secondary copper contacts; increase weld current by 10% on touchscreen.

Fault 2: Pitch Cumulative Drift & Inconsistent Spacing

Root Causes:

1. Loose coupling hub between servo motor encoder and carriage gearbox;
2. Weld spatter packed into drive rack causing tooth skip;
3. Position loop servo gain parameter drift.

Corrective Actions:

1. Tighten servo shaft clamping sleeves;
2. Clean rack and pinion teeth and apply extreme-pressure grease;
3. Re-verify electronic gear ratio in PLC parameters.

Fault 3: Servo Drive Overload Faults (AL-01 / AL-09)

Root Causes: Mechanical rail binding; acceleration rate too aggressive for heavy cages.

Corrective Actions: Lubricate way guides with ISO VG 68 way oil; increase ramp acceleration time from 0.5s to 1.2s.