Quantity based scheduling

Dear Guru,

I have 4 workcenter combained in routing operation 10, 20, 30 and 40.

in first WC operation 10 i can give the time for Base QTY 1 PC = 10 min

2nd WC operation 20 is cleaning bath where i can put only 40 PC ie 1 - 40 PC it will take 350 mins to complete the operation

3rd WC operation 30 is annealing where i can put 1 - 80 PC at a time it will take 150 mins to complete the operation.

Now my issue is how to define routing timing for this.

If the order qty is within 1 - 40 PC second operation should schedule for 350 min

if order qty is more than 40 - 80 PC second operation should schedule for 700 min

I am thinking to create LOT size based routing .. but operation 20 and 30 is making some confusion to me.

Please give me some light