Parts Judgment criteria Treatment
Housing, valve body • Scratches,rustorcorrosiononthepartsslidingagainstthe
spool
• Scratches, rust orcorrosionon thesealpocketpart that
the spool enters
• Scratches, rustorcorrosiononthe seal partonthe port
that is in contact with the O-ring
• Scratches, rustor corrosion on theseal partof the relief
valve, etc.
• Otherdamageconsideredtoimpairnormalfunctions
Replace
Replace
Replace
Replace
Replace
Spool • Scratchesontheslidingsurfaceofoutercircumference,on
which the fingernails get caught
• Scratches on parts that slide against the seals at both
ends
• Spooldoesnotmovesmoothly
Replace
Replace
Repair or replace
Load check valve • Imperfectsealingduetodamagetothevalveorspring.
• Operates smoothly when inserted and operated in the
housing
Repair or r
eplace
Normal
Around the springs • Rust, corrosion, deformation, breakage or other notable
damage to the spring, holder or cover
Replace
Around the spool seal •Oilleakagetotheoutside
• Rust,corrosionordeformationofthesealholder
Repair or replace
Repair or replace
Main relief valve, port re-
lief valve, anti-cavitation
valve
• Externalrust,damage
• Damagetovalveseatcontactsurface
• Damagetopoppetcontactsurface
• Abnormalityinthespring
• O-rings,backuprings,seals
Replace
Replace
Replace
Replace
Replace as a rule
Adjusting the main relief valve pressure
“2. Service data, Performance criteria”