The paper investigates the distribution and levels of electric field intensity in glass disc insulator chains used in 230 kV transmission lines. Eight different insulator models with different geometric configurations were analyzed, including the presence or absence of an air gap between the bell and the glass disc, a sacrificial sleeve on the pin and a glass protrusion around the pin. The simulations were performed using Comsol Multiphysics software, allowing a detailed evaluation of the electric field distribution. The simulation procedures involved 2D modeling of the insulators in AutoCAD and the simulation settings, where the dielectric properties of the materials and boundary conditions were applied. It was identified that in the insulator chain, the insulator closest to the cables is subject to greater potential differences between its bell and pin. The simulations indicate that the air gap between the bell and the glass disc does not represent an immediate critical risk, while the protrusion intensifies the field and accelerates handling. The sacrificial glove proved effective, keeping the field below the corona limits and specifically protecting the pin.