SQL Tools :: Decimal To Time Conversion

How to convert decimal to time .

I am using below code 

declare @hour decimal(18,4)='249.2644444444'
select  RIGHT('00' + CONVERT(varchar(2),FLOOR(@hour)),2)
+':'
+ RIGHT('00' + CONVERT(varchar(2),FLOOR(((@hour-FLOOR(@hour))*60))),2)
+':'
+ RIGHT('00' + CONVERT(varchar(2),FLOOR(((@hour-FLOOR(@hour))*60)-FLOOR(((@hour-FLOOR(@hour))*60)))*60),2)

For example 1 it works fine but example 2 it throws arithmetic error. Looking for right code which accepts any value and converts to time.

Example 1 : 12.0763888889 as 12:04:00.
Example 2: 249.2644444444 
error : Arithmetic overflow error converting numeric to data type varchar.