Flowserve Noble Alloy Ball Valve IOM - Manual (Page 4)

August 22, 2002, Rev. 2 2
2.0 INSPECTION AND CLEANING
2.1 Thoroughly clean the body (1) and tailpiece (2) of all residue, scale or deposits. Be very
careful not to scratch or damage the body seal or seat pocket surfaces during cleaning or they
may not seal properly. Visually inspect the seal areas for scoring, erosion, pitting or any other
damage. Inspect the ball cavity and waterways for erosion or significant loss of material. Any
damage to the seal areas or seat pockets must be repaired before the valve can be
reassembled. Inspection the packing bore for damage or galling. NOTE: Nobleized parts
cannot be weld repaired and must be returned to the factory for repair. Inspect the end
connections for corrosion or damage. Flanged valves' composite flange cannot be removed.
If there is damage to the composite flange, it must be returned to the factory for replacement.
Most surfaces can be polished with scotch-bright without damage. Inspect the body studs and
nuts for corrosion and galling and if damaged, they must be replaced.
2.2 Thoroughly clean the ball (3) and seats (4) (if metal) of all residue, scale or deposits. Soft
seats should be discarded and not be reused. Inspect the ball for erosion on the nose and
scoring or scratches on the sealing area. If the ball has been damaged, it must be discarded.
Nobleized balls and seats cannot be repaired and must be replaced. Inspect the metal
seats, if equipped, for erosion, scoring or scratches on the seal face. Place the seat on a flat
plate. From I.D. of the seat, place a feeler gauge between the seal lip and the plate to check
for yielding. The seat must be replaced in the clearance is less than .004". If the metal seats
are to be reused, be sure the backseat surface is clean and in good condition as this is
important to sealing on this design seat.
2.3 Thoroughly clean the stem (5) of residue, scale or deposits. Inspect the stem tang (the end
that engages the ball) for corrosion, twist or bending. Inspect the packing area of the stem for
scoring, corrosion or galling. Minor galling on the stem where it comes through the body
below the packing or around the tang is acceptable and can be filed or polished smooth. If the
packing area of the stem has any damage, it must be replaced, as it will allow the packing to
leak.
2.4 Thoroughly clean the balance of the top works, including the packing follower (10), packing
springs (11), spring cap (12), thrust bearing (13), shear collars (23), retainer (8), stop collars
(19), emergency adjusting set screws (18) and studs/nuts. All parts should be free of
corrosion, scale or residue. The packing follower (10) should fit easily over the stem. The
thrust bearing (13) should fit snugly over the stem shoulder but rotate freely. It should also fit
snugly into the retainer bore but rotate freely. If not, it should be replaced. Inspect the
packing springs (11) for any signs of corrosion and replace if they have any indication of
damage or corrosion. The set screws (18) should screw in and out of the retainer easily. An
anti-seize compound should be used on these. If they are damaged or frozen in the retainer
(8) replace both the retainer and the set screws. Remember, the emergency adjusting set
screws (18) are your back up packing adjustment should the live loading of the packing
springs fail or the packing start to leak.
2.5 All seals including the packing (9), body seals (7) and soft seats (if equipped) should never be
reused and should be replaced with new factory parts.