The surname Rang is a rare surname.
The surname Zeng is a simplification of the surname Rang. "炂" is always used in family trees.
This surname may have originated from a great Sima named '穰苴', so it was originally written as '穰'. It was rewritten as "Liang" and became the current "炂". This statement became even more certain after she discovered that many villagers had the word "穰" written on their stools and tables when she returned to her hometown.
The above two surnames have the same origin.
Let the last name be an irregular simplification. It is completely different from the above two surnames and cannot be reduced to the Rang surname.