Remove equipment from line process .
Test as found and record data.
Disassembly if test result leakage
Check condition of valve nozzle and disk seats, lapping accordance with manual
Check condition of internal parts for corrosion, scaleing and wear,
Clean , recondition or replace.
Check for pitting, cracking and end coil squareness of valve springs.
Check spindle for straightness and adjusting ring threads for free movement.
Reassembly , test and recalibration on bench test
If as found result no leakage , only adjust setting and test
As left data record
Reinstall equipment with new gasket ( provide by owner )
Other inspection as per O&M manual
Dismantling