Time tracking but adjusting hours and minutes only

A new column to present hours and minutes only!
For future planning our factory schedule and to measure capacity we have worked with time tracking but have to select a date and time period in the past that is not always useful to us, if we could only adjust the hours and minutes this will save us a lot of time. Having to also use a number column we can only use one unit of measurement which means we can only display minutes.

Anyone managed to find a work around for this?