SSIS convert flat file cell to HH:MM:SS
2) Time/Date datatypes are often problematic choices for storing durations. Instead use an integer or decimal for whatever resolution is appropriate (seconds or milliseconds are popular, but minutes may work for you in this case).

1) In this instance, the simplest option may be: (DT_I4)TOKEN(Column,":",1) * 60 + (DT_I4)TOKEN(Column,":",2).

Other methods:


If you will always have two characters each for hours and minutes, you can use something like (DT_I4)SUBSTRING( [Column], 1, 2 ) * 60 + (DT_I4)SUBSTRING( [Column], 4, 2 ).
If hours can be 1 or more characters, but minutes is always two: (DT_I4)SUBSTRING(Column,1,FINDSTRING(Column,":",1) - 1) * 60 + (DT_I4)SUBSTRING(Column,FINDSTRING(Column,":",1) + 1,2)