我想你可以添加到列TDate列Hour转换to_timedelta有unit='h'：
df = pd.DataFrame({'TDate':['2005-01-03','2005-01-04','2005-01-05'],
'Hour':[4,5,6]})
df['TDate'] = pd.to_datetime(df.TDate)
print (df)
Hour TDate
0 4 2005-01-03
1 5 2005-01-04
2 6 2005-01-05
df['TDate'] += pd.to_timedelta(df.Hour, unit='h')
print (df)
Hour TDate
0 4 2005-01-03 04:00:00
1 5 2005-01-04 05:00:00
2 6 2005-01-05 06:00:00
602392714
清零编程群