Scrapper Tee
Scrapper tee or sphere tee or flow tee
essentially consists of concentric barrel tees. The purpose of the scrapper tee is not to allow passage of
the pig sphere/scrapper on the
branch side.
The scrapper tee shall be suitable for
pigging operation with process hydrocarbon/saw sea water. The scrapper tee
inside diameter shall be same as that of
inside diameter of riser in splash zone to maintain constant ID to
permit smooth pigging operations.
No bar shall be used.
Maximum possible opening shall be provided
through slots to limit the pressure drop i.e total opening shall be 1.0 to 1.5 times the branch pipe area.
Thickness of run/branch is to be calculated by vendor to the required design
pressure and temperature and it shall match with the corresponding matching pipeline for free passage of pig as per DNV rules for
submarine pipeline.