The following procedure should be used when cleaning out the PBR for setting a weight set tie-back packer with a 7in liner.
1. RIH combined lower, upper tie-back polish mills and casing scraper.
2. Position of packing element relative to top PBR when set must be established to ensurethat scraper will clean setting area if it is run in combination with casing mills.
3. A separate 9.5/8in casing scraper to TOL may be required.
4. Circulate at 4 bbl/min and rotate at 40 rpm. Lower mill into PBR of liner hanger. Pressure will increase as mill lands off.
5. Mark the pipe and pick up 3m. Rotate at 40 rpm and circulate at 4 bbls/min until mills are clear of PBR.
6 Circulate clean, do not enter the PBR again.
7. POOH check drillpipe tally and drift all drillpipe including pup joints. Check mark on mill at surface.