In a power supply without a transformer for a 110 V network, I am using a 450 V capacitor. Okay, but there is a voltage transient above 450 V, what will happen to the capacitor? Does it burn?
Probably not, as the transients usually have short duration, insufficient for the capacitor to respond by charging itself to the point of surpassing 450 V. Only if there is an over voltage in the power grid that lasts more than a few milliseconds can it happen something. Short transients should not jeopardize your capacitor and power supply.
