Difference between Core type and Shell type Transformer is as follows:

Sr.No.

Core Type

Shell Type

1.

The winding encircles the core.

The core encircles most part of the winding.

2.

It has a single magnetic circuit .

It has a two magnetic circuit.

3.

The core has two limbs.

The core has three limbs.

4.

The cylindrical coils are used.

The multilayer disc or sandwich type coils are used.

5.

The windings uniformly distributed on two limbs hence natural cooling is effective.

The natural cooling does not exist as the windings are surrounded by the core.

6.

The coils can be easily removed from a maintenance point of view.

The coils can not be removed easily.

7.

Core type construction  is preferred for low voltage transformers.

Shell type construction is preferred for high voltage transformers.