when does it want to use barred tee 3

[johnhovard23]

hi every body,
please help for this.
question: the barred tee is used for expand a connection to the branch of available for pigging pipeline. but for small diameter branch, it does not want the barred tee. how nuch does the limited ratio of mainline diameter to branch diameter for chosing to use barred tee?
thank

 

[zdas04]

It really depends on the kind of pig you are running. A mandral pig will never make the turn into any size branch. A foam pig will pretty much go through whatever pipe has the lower pressure (I once had a 10-inch uncoated foam pig go through a 2-inch weld-o-let on a receiver barrel, but it took a while and did not remain intact). Realistically, I always bar tees since most company standards only allow reducing tees to be used down to 1/2 the run diameter (i.e., I can use a 10X6 tee, but not a 10X4 if I could buy one). 1/2 the diameter can take a coated foam pig and some turbo pigs. I don't bar weld-o-lets.

David Simpson, PE
MuleShoe Engineering

"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.

 

[11echo]

We use foam pigs and nerf ball type pig all the time in my area, we use barred tees down to half the diameter of the main line.