The history of the 62nd Army 

The 62nd Army was activated in July 1942 from thr 7th Reserve Army. It's commander was
Major General V. Ia. Kolpakchi.
 

General A.I. Lopatin
Lieutenant General A. I. Lopatin commander of the 62nd Army. 
(August - September 1942)
He decided Stalingrad could not beheld, and began to widraw his
units without orders, so there was nothing for it to dismiss him*.
For the time being his Chief of Staff, Major-General Krylov took 
over command until he was replaced by Vasiliy Ivanovich Chuikov.
Chuikov  took over on September 12th, 1942.
*Dismissed by Yeremenko, commander of the Stalingrad Front. 

The 62nd Army was reformed into the 8th Guards in April 1943.