use of Vlookup for a range of values

Hello friends..
I have an excel sheet which helps to calculate pip e thickness and shcedule. The schedule is selected based on thickness calculated for eg. On “refdt” sheet, when the pipe thknss is calculated as something in between 0.065 to 0.109, the schedule should be selected as “40”. For some value which is <= 0.147 but greater than 0.109 , the schedule selected should be “80”
The nested If function do not work for this as too many conditions are involved. How do we apply Vlookup to this data for searching in a range? Please advise.(sheet attached)

Thanks
Maoj