Quality Policy

Where Does Quality Begin?

In winding conductor, it is not possible to reduce quality to a single check step before shipment. An insulation defect in a conductor that has already entered the winding only shows itself after the machine is commissioned — often when the winding cost has already been incurred. Our quality process therefore begins with the technical definition of the order and continues, through records, even after delivery.

Incoming Material Control

Every batch passes documentary and physical control before it is taken into stock:

• The batch/cast number on the shipping document, reel label and certificate is verified to match.
• Conductor size is checked: conductor diameter and coated outer diameter on round conductor; width, thickness and corner radius on flat conductor.
• Scratches, peeling and colour difference on the enamel surface; edge damage, loose winding and moisture marks on paper/aramid insulation are inspected visually.
• Reel flange, packaging integrity and moisture barrier are checked; in case of doubt the batch is quarantined.

Thermal Class Verification

Thermal class is the most misunderstood topic. A conductor being "class 180" does not mean it will run indefinitely at 180 °C; the IEC 60085 classification rests on a temperature index determined by the IEC 60172 method and sits on an accepted thermal-life basis. In acceptance, the declared thermal class is compared with the manufacturer test report and the product label; whether it is consistent with the expected temperature rise in the winding design is assessed by the technical team.

Test Methods Applied (IEC 60851)

Verification tests are run through methods that represent winding behaviour:

• Dimensional: measurement of diameter, width, thickness and build increase (IEC 60851-2).
• Mechanical: elongation at break, springback, flexibility and adhesion by mandrel winding, peel/scrape resistance (IEC 60851-3).
• Electrical: dielectric breakdown voltage and insulation continuity/defect count (IEC 60851-5).
• Thermal: heat shock and softening/cut-through temperature (IEC 60851-6).

On paper and aramid-insulated conductors the insulation material itself is also evaluated: IEC 60554 for cellulosic papers, IEC 60819 for non-cellulosic aramid papers and IEC 60371 for mica-based insulators are taken as the basis.

Certification and Traceability

Every batch shipped is delivered with an EN 10204 3.1 material certificate. The certificate contains conductor material and purity, size, insulation type, thermal class, build grade and batch/cast number. In our warehouse records each reel is linked through this number; so the question "which batch went into which winding" can be answered even years later. When a non-conformity is detected the batch is blocked, root-cause analysis is carried out together with the manufacturer, and the result is reported to the customer in writing.

Storage and Handling Rules

Quality must be preserved after the material is taken into stock as well. On paper and aramid-insulated conductors, moisture is the greatest threat: the dielectric strength of insulation that takes up moisture drops and transformer drying time lengthens. These groups are stored in closed, moisture-barrier packaging, without contact with the floor; a use priority is defined for batches whose packaging has been opened.

On enamelled conductors the main risk is mechanical damage. Reels are stacked upright, corner protection is applied against flange impact and stacking height is limited. In handling, a suitable fixture is used instead of a hook; every point that touches the conductor surface is checked because it carries the possibility of film damage. First-in first-out (FIFO) is applied in warehouse records.

Continuous Improvement

Customer feedback and events such as breakage, film damage or dimensional deviation experienced on the winding line are recorded and reflected in supplier evaluation. Recurring findings result in tightening the product acceptance criteria.

We track our quality targets through measurable indicators: batch-based non-conformity rate, number of customer complaints, on-time delivery percentage and delays caused by missing documents. These indicators are reviewed periodically; on items below target, root-cause analysis is done and corrective action planned.