To create regular clusters you could use the function class(). Unregular clusters are also possible but the effort is higher because then it will be some if-loops within the function needed.
Easier is often to use a mapping with applymap(). Therefor you needed only a round function or a similar logic to create fixed values then a greater or less then isn't possible:
Mapping Load * Inline [
0, 0-2 Hrs
1, 0-2 Hrs
2, 2-4 Hrs
3, 2-4 Hrs
applymap('HourMap', floor(Hrs), 'DefaultValue') as HrsCluster
Such mapping-tables are easily created in excel even if you have then 24 hrs.