Sanitation of dried ingredient pipes such as sugar and flour

Good evening everyone, I currently work for an industrial bakery, in the QA team, and we make lots of things such as break, muffins and cookies. For our cookie lines, ingredients are mostly added by hand by operators. Then we add extra flour and sugar through automatic food grade stainless steel pipes falling straight to the mixture before being mixed. These pipes can hardly be removed, or they are through a long break with maintenance. So they aren't cleaned at every single sanitation. I have just noticed that nasty things are building up inside the pipe, all around and they aren't removed regularly. I did some research and found the Rotaflex flour cleaning system that would be nice. But I'd like to hear what other professionals working with similar ingredients and process have experienced with that! Thank you, Coraline 

of course I meant flour the whole time and not floor!