Quality Control
Quality control at JINXING spans the entire production lifecycle — from incoming material inspection to final pre-shipment verification. Every transformer is traceable from raw material to delivery.
QC Checkpoints Throughout Production
Incoming Material Inspection
Core Steel
Verification of grain orientation, thickness, and specific loss values per certificate before cutting.
Copper Conductors
Dimensional inspection, resistance measurement, and insulation paper quality check.
Insulating Oil
Breakdown voltage, moisture content, and dielectric loss testing on every oil batch.
Accessories
Function testing of OLTC, Buchholz relay, temperature controllers, and other components.
In-Process Quality Control
Core Geometry
Step-lap joint verification, core loss measurement before and after assembly.
Winding Tension
Controlled winding tension and turn-count verification for each coil.
Insulation
Insulation resistance check after drying and before oil impregnation.
Assembly Tolerance
Dimensional checks for core-coil assembly fit, clearance, and clamping force.
Final Quality Documentation
Test Reports
Full routine test report with every unit — in English, with measured values and pass criteria.
Nameplate
Verified nameplate with all rated data, serial number, and manufacturing date.
Material Certificates
Available on request — core steel, copper, oil, and accessory certificates.
Traceability
Each unit has a unique serial number traceable to all material batches and test records.
Quality built into each stage
Inspection points cover incoming materials, winding and core dimensions, assembly, drying, final testing, documentation and packing.
Want to learn more about our QC process?
Contact us for our detailed quality control procedures, or arrange a factory audit and witnessed inspection.