In recent time, in response to increasing costs of material and labour, a new concept, in heat exchange by use of corrugations on transformer tanks is emerging very fast. It has virtually eliminated the radiator's concept and due to its Hermetically Sealed construction it eliminated the contact of oil with the outside atmosphere, thus making whole arrangement totally maintenance free .The distribution transformer is provided with a corrugated finned tank. The role of the fins is to increase the surface of the tank which is in contact with cooling air. Due to the temperature rise of the windings under load, the oil temperature also rises.
The hot oil rises, meets the top cover and goes down into the fins where it is cooled by the air rising up between the fins. As the number and depth of the fins increases and their width decreases, the oil cooling improves.
| PANEL WIDTH | H1 | 500 – 1200 mm |
| SHEET THICKNESS | S | 1.0/1.4 mm |
| RIB GAP (INSIDE) | G | 8 mm |
| RIB DEPTH | D | 50 – 400 mm |
| RIB PITCH | P | 40 mm To 50 mm |
| No. OF CORRUGATIONS | n | AS REQUIRED |
| PANEL LENGTH | L | AS REQUIRED (TO CORRESPOND TO TANK INTERNAL DIMENSION) |
| WELD FLAP | F1 | 10 mm (AT 90° TURNED OUTWARDS) |
| WELD FLAP | F2 | 10 mm (STRAIGHT) |
| No. OF PANELS | N | AS REQUIRED |
| TYPE OF RIB | R | R1 or R2 or R3 or R4 ( ‘D’ MIN. 160 FOR R3 or R4) |