Why were only some of my tools damaged when connected to a 240V receptacle?
Many devices are rated for either 110 or 220. There should be a tag on the device which says this. In some appliances its done intentionally so that one model can be sold and safely used in countries which use either voltage. In other cases its simply dumb luck that the component parts can tolerate either voltage.

I'm not sure if this fully answers your question. "The device is rated for it" doesn't really cover what aspects of the device make this possible.