"Ensamble del conjunto núcleo – bobina (Armado) y fijación al tanque (Encube)

Ensamble del conjunto núcleo-bobina (Armado) y fijación al tanque (Encube). Este proceso consiste principalmente en acoplar el núcleo a las bobinas, aislar y acondicionar las guías de salida de B.T y de A.T. después de haber sometido las bobinas a un proceso de horneado (curado) con la temperatura y tiempo anteriormente mencionados.
Luego, se realiza la sujeción mecánica del conjunto con la prensa y posteriormente, se procede a aislar las salidas terminales. También se soldan los conectores a las guías de A.T y se hacen las conexiones al cambiador de derivaciones.
Seguidamente, se procede a fijar el conjunto al tanque"
https://ciencia.lasalle.edu.co/cgi/viewcontent.cgi?article=1... (photo on page 22 of the document - figure 3)

Other photos here explaining the final stages (in Spanish) of the manufacture of a transformer - https://slideplayer.es/slide/5745190/18/images/10/Proceso de...

Video here of the 'encube' process - https://www.facebook.com/transformadoresarm/videos/encube-de...

"Tank Up
After removing the Core-Coil Assembly from the heating oven, it is thoroughly cleaned by pressurised dry air and then placed into the tank and bolted up. All necessary accessories / fittings such as bushings, valves, oil level indicator, pressure relief device, temperature indicator, tap changer etc. are fitted on to the tank body. High quality filtered transformer oil is then filled in the tank to completely immerse the assembly. Finally, connections of primary and secondary to the terminal bushings are made."
https://www.marsonselectricals.com/marsons_asp/manufacturing...

"Tank - Up :
The core-coil assembly and tank supplied by the fabrication deptt. are taken into tank-up stage.
The procedure is :
The core-coil assembly is taken out of the oven and the "Megger test" is carried out.
Only if the megger value is as per the specification, the assembly may be taken for tank-up.
The tanks, supplied by fabrication deptt. are brought to tank-up department duly painted.
Fittings like drain valves, HV& LV Bushings, conservator, oil level indicator and explosion vent are fitted in the tanks.
The Core-coil assembly is then placed into the tank and properly locked up.
Pure filtered transformer oil is filled in the tank to immerse the assembly only.
Connections of primary and secondary to the terminal bushings are made. Operating handle for ratio switch is fitted, wherever required."
http://national-electrical.com/transformer india.html

"5. Tank Up
Oil-filled - The core and coil assembly is dried in an oven at a temperature of 90°C - 110°C, to improve insulation resistance and remove ingress of moisture in the insulation materials. The dried core coil assembly is boxed up in a pre-fabricated MS Tank, and vacuum process is applied for filling oil in the transformer tanks. Oil-filled in transformer will be PCB free Mineral oil / Midel 7131 / Silicon oil / Ester oil / Nynas Nytro etc. as per customer’s requirements.

Dry Type - The core and coil assembly is enclosed in metallic enclosure designed and fabricated in accordance with NEMA or customer’s specification and HV/LV connections are covered with heat shrinkable sleeves & epoxy terminal boards."
https://www.kotsons.com/our-manufacturing

Photos of 'tank up' process here - https://www.facebook.com/dynamicpowereng/posts/transformer-t...