If you don't feel like spending many hours in a train, you can consider travelling by plane. Especially if you have the possibility to book in advance, flying to Chelyabinsk can be definitely cheap.
In which stations can you take the train to Chelyabinsk and where will you arrive?
The trains to Chelyabinsk leave Kazan’ from ВОССТАНИЕ ПАССАЖИРСКАЯ and arrive in ДУБРОВКА ЧЕЛЯБИНСКАЯ.
When are the first and last trains from Kazan’ to Chelyabinsk scheduled?
It will take you 24 hours and 29 minutes to reach Chelyabinsk. The earliest train leaves Kazan’ at 07:03, whereas the last one leaves at 07:03.