Oil seals

Oil seals close spaces between stationary and moving components in mechanical equipment, helping prevent lubricant escape. They also stop harmful contaminants from entering machinery.

Oil seals are lightweight compact and provid stable sealing, so these are uesed in wide range of machineries such as cars, motorcycles, construction/agricultural/industrial machineries and so on.

Standard oil seals

Model and Shape Feature Use
Rubber seal (Periphery rubber) S type (S)
  • Standard oil seal
  • Standard rotating shaft
SD type (D)
  • Standard type with dust lip
  • Rotating shaft
SO type (G)
  • Standard type without spring.
  • Low-speed rotating shaft
SDO type (-)
  • without spring, with dust lip
  • Low-speed rotating shaft
AF seal AFJ type
  • standard type with AF
  • AF : polytetrafluoroethylene
  • High temperature, high-speed axis
  • Low torque, Low lubrication
FPJ type
  • with AF, standard type with dust lip
  • AF : polytetrafluoroethylene
  • Same as FAJ type

Special Shape Oil Seals

Model and Shape Feature Use
SQ type
  • Shape of combining S type back to back with each other
  • It sealable two kinds of fluids at once.
  • Crankshaft for two-stroke engine.
  • Separation of engine oil and gear oil.
  • Separation of oil and water of outboard motors.
SP type
  • High pressure resistant seal by reinforcing the lip
  • Usable as 3 - 5㎏/cm2 rotating shaft.
  • Shaft seal for pump
  • Converter、hydraulic clutch and so on.
  • Depending on number of revolutions, AP seal is effective.
SID type
  • Used for deformation of SD type, where there is concern that the dust lip will turn over on installation.
  • Grease retention between lips.
  • For the place where shaft insertion is performed after installing oil seal such as mission, differential gears.
OS type
  • Outer side sliding seal when a housing turns and an axis is fixed.
  • The oil seal is not affected by centrifugal force
  • Seal for front axles of the car.
Spiral seal
  • It is a seal with a rib on the lip part and it can be applied to other than AF lips.
  • Especially effective for stabilizing initial sealability.
  • It can be effectively used when the shaft rotation is only in one direction, such as front and back of the crankshaft of the engine.
SDD type
  • SSD or SDO type dust lip for muddy double and triple in particular.
  • Used for slight muddy water.
  • Axle seal of the motorcycle
  • Seal of differential gears of automobile / cultivator
SDD4 type
  • SD or SDD type with additional labyrinth part or thrust lip.
  • Can be used for moderate mud
  • Seal of exposed part such as motorcycle and front hub of automobile, water seal for domestic appliances such as washing machine, mixer, disposer and so on.
DD type
  • Mainly to prevent invasion of dust and muddy water from the outside.
  • It can seal the lubrication grease.
  • As with the SDD 7 type, when there is no worry about the internal lubricant leakage.
M type
  • Dedicated seal for mud etc.
  • Since friction torque is large, it can not be used other than low speed rotation.
  • Seal for cultivator's axle.
SS type
SR type
  • 補強金具なしのオイルシールで(SR type)取付け、取外しの困難な場所では1ヵ所切断のSS typeを使用、スプリングは軸にまき込んだ後にジョイントする
  • Seal for automobile crankshaft
  • Seal for roller shaft of papermaking machine etc.
RSD type
  • Seal for reciprocating shaft.
  • Shock absorber for automobile, motorcycles and so on.
  • Motorcycle front fork
  • Scraper of hydraulic cylinder.
OV type
  • It is installed in the O-ring groove of a piston etc. One-way pressure seal.
  • Medium pressure with small sliding resistance.
  • Oil pressure clutch piston use
  • Piston seal for air cylinders.
U type
  • Packing for reciprocating high hydraulic pressure.
  • A sliding resistance is small in a groove of a piston or the like.
  • Same as V type

Main characteristic of rubber.

Kind of materials and application criterion

Materials Use Application specification Application temperature (℃) target
Usable Unusable

Low-temperature rotary

JIS B 2402-A
JIS B 2402-B

-30 ~ 100
-30 ~ 120
(Less than 80℃ in gear oil)

  • Lubricating oil
  • Engine oil
  • ATF
  • Gear oil

Ester Synthetic Oil

Low-temperature rotary

JIS B 2401-2

-30 ~ 100

fuel oil

Ester Synthetic Oil

Low-temperature rotary and reciprocating

JIS B 2402-A
JIS B 2402-B

-30 ~ 100
-30 ~ 120

  • Grease
  • Mud
  • Hhydraulic oil

Ester Synthetic Oil


Medium-temperature rotary


-25 ~ 130

  • General lubricant
  • Engine oil
  • Turcon oil
  • Gear oil
  • Fuel oil

Ester Synthetic Oil


edium-temperature rotary

JIS B 2402-C

-30 ~ 150
(Less than 130℃ in gear oil)

General lubricant

  • Fuel oil
  • Acid
  • Alkali

High-temperature rotary

JIS K 6380- CⅠ803

-50 ~ 180

Engine oil

  • Gear oil
  • Fuel oil
  • Acid
  • Alkali

high-temperature rotary use and
High temperature reciprocating motion use

JIS K 6380- CⅡ810

-30 ~ 230
(Less than 170℃ in gear oil)

  • General lubricant
  • Fuel oil
  • Acid
  • Alkali




  • Water, Steam, Chemical fuel oil
  • Others

※The application temperature range is a standard value when used for fixing, and there are some differences depending on usage conditions.