The processing is rather quick, a quick nanoshot and applying the collar and leg cuff. The usual routine is to give the new ones something to do, brings them faster into the routine.
The control collar keeps them away from where they can't go anyway and also keeps them safe more or less. The guards are a bit loose on applying shocks to inmates who bully the newcomers. It is something that has no particular rule and comes with experience.
The newcomers have to be broken, and letting them fall into their place hastens that but letting them get hurt is a waste too. It's a balancing act of keeping your investment healthy and assuring that it will be ready for its intended purpose as fast as possible.