[1] His father, Léon-Joseph Ranque, worked as an engineer for a railroad; his mother was Joséphine Saint Germain.
[3][4] In 1923, Ranque went to work for the Saint-Jacques steelworks in Montluçon, where he improved methods of producing steel.
He became head of the metallurgical laboratory at Saint-Jacques, where he helped develop steels that would be used as armor in tanks and in the Maginot Line.
The couple had six children: Marie-Josèphe, Pierre, Marie-Noëlle, Marie-Thérèse, Monique and Marie-France.
After the war, he accepted a position at the Aubert et Duval steelworks in Les Ancizes.