Microduct

laketime

Senior Member
Installed microduct for future fiber, supplied by owner (the city), and the engineer wants us to install a pull string in each microduct. The interior diamter of the microduct is a tight 5/8" and the runs are over 450' long. Any ideas on how to accomplish this besides buying a $1,500 string line blow gun?
 

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
Microduct...
fought that in a place or two.. it sounds silly, But...

a vacuum on one end, a small (very small) rag or piece of cloth, and a fishing rod on the other end.
once I got the fishing line in there I pulled in my pull string with the reel. Almost like fishing...
Didn’t want to chance a 600’ fiber pill with 20 lb monofilament..
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
Just to clarify my previous post, that particular "shot" is too large and too short, I meant try something similar to that where the string is very thin and light so that a vacuum can pull an object 450'. You might try a small piece of plastic bag with the "shot" or fishing line tied to it. From there you can pull in a larger drag line.
 

GoldDigger

Moderator
Staff member
There is something to be said for unreeling the line from the spindle instead of trying to drag the line against the conduit for the length of the pull. But the pictured assembly looks like it might have problems with even sweep turns along the way.
On the other hand, a conduit designed for fiber would have to have large radii along the route.
 

laketime

Senior Member
I am not a fiber guy either. We installed the microduct for the customer and the engineer is using a spec for string in unused or future conduits to have us use a string in the microduct.
 

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
I am not a fiber guy either. We installed the microduct for the customer and the engineer is using a spec for string in unused or future conduits to have us use a string in the microduct.
Normally the fiber is blown in during installation with a blow gun.
Some engineers on long pulls want a string in there if for no other reason than to guarantee that “something” will go through the duct And there are no obstructions, kinks, or crushed ducts..
 
Top