On a regular Table with a live dealer -depending on the number of players from 1 to 6 or 7 maximum and number of bets, I would say the following:
1. One Player - "outside bets only" - a spin every 20 seconds is probably possible = 180 spins per hour. But this would be nearly physically impossible over any length of time.
2. 6 or 7 Players - betting lots of chips all over the layout and chips being "mucked" by hand - probably up to as much as 3 minutes a spin = 20 spins per hour.
3. Averaging everything out I would guess under all conditions - my estimate would be a minute and a half per spin = 40 spins per hour.
For what is worth - that's my best estimate !!
I assume somewhere Casinos keep track of spins per hour and have a "standard" they would like to meet on a day to day basis. Would be interesting to get actual data from a Casino on this subject.
Take care,
"Mr. Roulette"