TM 10-4320-307-24
4-4
PUMP ASSEMBLY MECHANICAL SEAL REPAIR (CONT)
CLEANING/INSPECTION/REPAIR:
Dry cleaning solvent is potentially dangerous. Avoid repeated and prolonged breathing of vapors
and skin contact with the liquid. Do not use near open flame, arcing equipment, or other Ignition
source. Always wear eye protection and protective clothing.
Death or serious Injury could occur if compressed air Is directed against the skin.
Do not use compressed air for cleaning or drying unless the pressure is/has been reduced to 30 psi
(2.11 kgcm2) or less. When working with compressed air always use chip guards, eye protection,
and other personal protective equipment.
1.
Clean metal components with dry cleaning solvent and dry with compressed air.
2.
Inspect tolerances on associated parts as follows:
a.
Shaft diameter in seal area: nominal size 0.00/-0.002 inch (0.00/-0.05 mm)
b.
Shaft finish in seal area: 0.8 micrometers center line average
c.
Shaft end play: 0.004 inch (0.1 mm maximum)
d.
Shaft run-out in seal area:
Size
Tolerance
0.984 in. (25 mm)
0.001 in. (0.03 mm)
1.968 in. (50 mm)
0.002 in. (0.05 mm)
2.953 in. (75 mm)
0.003 in. (0.08 mm)
3.937 in. (100 mm)
0.004 in. (0.10 mm)
e.
Squareness of shaft to staffing box face:
Size
Tolerance
0.984 in. (25 mm)
0.002 in. (0.05 mm)
1.968 in. (50 mm)
0.002 in. (0.05 mm)
2.953 in. (75 mm)
0.003 in. (0.08 mm)
3.937 in. (100 mm)
0.004 in. (0.10 mm)
f.
Concentricities of sleeve and box bore:
Size
Tolerance
0.984 in. (25 mm)
0.002 in. (0.05 mm)
1.968 in. (50 mm)
0.003 in. (0.08 mm)
2.953 in. (75 mm)
0.004 in. (0.10 mm)
3.937 in. (100 mm)
0.005 in. (0.13 mm)
3.
Repair as follows:
a.
Replace all packings and gaskets each time mechanical seals are all disassembled.
b.
Recondition seal faces if facilities are available.
c.
Metal components may be lightly polished but must not be re-machined.
d.
Polish shaft sleeve score marks. No more than 0.0004 inch (0.01 mm) should be taken from any diameter.
e.
Check the condition of seal face protection washer and replace if necessary.
4-6
