Converting string ex. "117:50:00" into hours

[adrianoramos520]

Well. I have two collums with a start service and other with the date closed as pic below:

I inserted a new collumn with the code:

(h):mm:ss =

var Hora= QUOTIENT('Incidentes (2)'[Segundos],3600)

var Minut0= QUOTIENT('Incidentes (2)'[Segundos]-'Incidentes (2)'[var Hora]*3600,60)

var Segundo='Incidentes (2)'[Segundos]-'Incidentes (2)'[var Hora]*3600-'Incidentes (2)'[var Minuto]*60

return

CONCATENATE(CONCATENATE(CONCATENATE(CONCATENATE('Incidentes (2)'[var Hora],":"),'Incidentes (2)'[var Minuto]),":"),'Incidentes (2)'[var Segundos])

And I got the result I wanted but as "String" and I'm not able to convert it into hours. So I can't find the time average and others calculations I expected.

When I try to convert it I get the message: "Its not possible convert the value '117:50:0' type of String into Date".

What am I doing wrong? Could you please help me?

Thanks a lot.