join pipes in a continuous geometry ???

Hello , I am stuck on a problem and i could use some help ..

I have a beam branching system which is actually a system of lines that intersect in points, and i used the component "pipe" in order to create the geometry of the beam . the problem , as you can see in the  picture, is that i can not create a continuous geometry in the articulation .. the initial idea was that this stucture should be continuous from branch to branch . I tried to use the component loft or fillet but of course it didn't work . I am running out of ideas .. anyone who can give me some ?