First transformer ever to be rendered bullet resistant by retrofitting
Siemens has received an order for the world’s first bullet resistant retrofit solution for a power transformer. The two, three-phase transformer units have been in service since 2013 and 2014, and play a strategic role in the US power grid.
Siemens Transformer Lifecycle Management (TLMTM) will design the retrofit solution and install shielding to protect the tank and conservator from all sides. The protection system panels have been designed and tested to withstand rifle projectiles according to VPAM Class 13, the highest class of rifle projectiles specified by VPAM, and the most powerful commonly available bullet that is not considered a destructive device under the United States National Firearms Act.
The transformers’ current oil-filled bushings will also be exchanged and replaced with HSP Resin Impregnated Synthetic (RIS) bushings. This means that even if a RIS bushing is penetrated by a bullet, it will not lead to fire because the polymer insulated bushings do not contain oil.