1.
What is sealing?

2.
Comparison of sealing system (1)
Without sealing
•Much leakage rate
(Impossible to seal)
With oil seal
•No Good for High Pressure
& Water
•Flaw on the Shaft
Sealing?

3.
Comparison of sealing system (2)
In Gland packing
•Shaft Sleeve is worn
•Leakage is required
(for Lubrication)
In Mechanical Seal
•Little Leakage
•No Abrasion of Shaft Sleeve
Sealing?

4.
What is Mechanical Seal?

5.
CATEGORY OF SEAL TYPE
SEAL
EQUIPMENT
GASKET・SEAT PACKING
O RING
LIQUID PACKING
STATIC
SEAL
D
Y
N
A
M
I
C
S
E
A
L
MEHCANICAL SEAL
GlAND PACKING
OIL SEAL
CARBON RING SEAL
LABYRINTH SEAL
ROTATING
SEAL
RECIPLOCATING
SEAL
U PACKING・V PACKING
O RING
PISTON RING SEAL・CARBON RING SEAL
SEAL FOR
GAS
SEAL FOR OIL
SEAL FOR WATER
SEAL FOR
OIL,WATER,ALKALINE,ACID
SEAL FOR
LIQUID
Seal ?

6.
“Mechanical Seal is applied to the sealing portion at
the rotating equipment (Pump,Compressor etc.) and for
the purpose of sealing the liquid is from between the
rotating portion and the stationary portion of the
Mechanical Seal.”
Flushing Piping
Volute Room
Impeller
Wear ring
Stuffing Box
Mechanical Seal
Bearing Box
Shaft Suction
Discharge
Mechanical Seal ?

7.
For Ethylene
－３０℃
For Water
For Hot Oil
３２０℃
For oil
Mechanical Seal ?
For any applications ?

8.
gland
Mechanical Seal ?
Installed in the gland of pump

9.
Mechanical seal cover
Sleeve
Rotor
Shaft
Stuffing box
Mechanical
seal cover
Sleeve
Mechanical Seal ?
Installed in the gland of pump

10.
Rotating Unit Stationary Unit
•It has Rotating Unit and Stationary Unit.
•Main parts are structured by Rings.
Mechanical Seal ?

11.
End Face Seal
Cylinder Face Seal
Gland Packing Oil Seal
Mechanical Seal
Flat Face
Round Face
Mechanical Seal ?
It has to be made by soft
materials as such Rubber,
PTFE,etc.
Comparison of Seal Face
No Restriction of Materials

12.
Mechanical
Seal
Gland Packing
Oil Seal
Performance
Pressure
Shaft Speed
Temperature
Slurry
Fluid
Mechanical Seal ?
Comparison of Applicable Range

13.
Component of Mechanical Seal
Mechanical
Seals
Seal Ring・Mating Ring etc.
O‐Ring・V‐Packing・Bellows・Gasket etc.
Pin・Clutch・Set Screw・Bellows etc.
Spring・Bellows etc.
Seal Component (Sliding Face Ring)
Packing
All the components are indispensable.
Spring Component (Spring Parts)
Driving Component (Torque transmission Component)
Mechanical Seal ?

14.
Component of Mechanical Seal
Sliding Face Ring
(Mating Ring)
Sliding Face Ring
(Seal Ring)
Packing・Spring Component・Driving
Component(Metal Bellows)
Packing
(O-Ring)
Packing
(O-Ring)
Driving component
(Set Screw)
Mechanical Seal ?

15.
Key point of Mechanical Seal～Seal Face～
Carbon(Material) etc.
Sic,WC etc.
Fluid
Atmosphere
Gap (0.5～2.5μm)
Expand
Mechanical Seal ?
Lubrication
membrane

16.
If the gap of the Seal faces...
Too wide Big leakage
Too narrow Seizure & damage the Sliding face
Proper(0.5～2.5μm) High performance & Long life
For making the gap of the Seal Faces proper...
•To finish the flatness and the roughness of the Seal Faces
super precisely.
•To add the suitable and flat pressure to the Seal Face.
•To assemble accuracy.
Key point of Mechanical Seal～Seal Face～
Mechanical Seal ?

17.
Flatness observed by the Optical Flat
Good No good
The suitable Roughness
of Seal Face
SiC: max Rz 0.4μm
Carbon:max Rz 1.0μm
Key point of Mechanical Seal～Seal Face～
Mechanical Seal ?

18.
Closing Force Fc Spring
force
Force pushed
by pressure
Rotating shaft
Stationary
Ring
Sealing fluid
Rotating
Ring
Seal face
Mechanical Seal ?
Mechanism of working

19.
Seal Face Area A
Opening Force Fo
Seal Face
Pressure
P
＝
Closing Force Fc ー Opening Force Fo
Seal Face Area A
Rotating
Ring
Stationary
Ring
Sealing fluid
Closing Force Fc Spring
force
Force pushed
by pressure
Mechanical Seal ?
Seal Face Pressure?

20.
Ｂ．Ｖ．（％）＝ Ａ0
Ａ ×100
B.V.>100%…Unbalanced Type
B.V.≦100%…Balanced Type
Area pushed by pressure
Seal Face Area
Balance value
Balance Value of
Bellows Type
（A0<A)
Balanced Type（A0<A)
Unbalanced Type（A0>A)
Mechanical Seal ?
Balance Value (Balance Ratio)?

21.
PV Value The Loading Value of Mechanical Seal
Large→ Hard condition
Small→ Light condition
PV Value ＝ Seal Face
Pressure P
× Velocity V
Theoretical PV Value :Net PV Value (including opening Force)
Process PV Value：Box pressure Pｓ × Shaft Speed V
Mechanical Seal ?
PV Value?

22.
2000
1980
1970
EKK Mechanical Seal
Applicable Range
Pressure
(MPa)
Size
(mm)
Slurry
(wt%)
SPEED
(m/s)
Temperat
ure
(K)
Viscosity(×1000Pas)
200
80 60
40
20
160
120
80
40
2
1
20
16
12
8
4
800
600
400
800
600
400
200
Mechanical Seal ?

23.
Engineering Trands of Mechanical Seal
• Cartridge seal
• Static seal
• Tandem seal
• Non cooler
• Non quenching
• Dry
• High grade seal face
material
– SiC(Silicon carbide)
– High performance
carbon
• Compact
High Reliability
High Performance
Long Life
Integration
KEYWORDS
For further requirements
Mechanical Seal ?

24.
Classification of Mechanical Seal

25.
Pressure Range
Spring Location
Installation Location
Arrangement
Spring Design
Assembly Design
Secondary Seal
Stationary Ring design
Unbalanced / Balanced
Rotating / Stationary
Inside / Outside
Single / Double / Tandem
Multi / Single / Bellows
Non Cartridge / Cartridge
Ｖ-packing / Ｏ-ring / Bellows
Clamp / Press Fit / Float
Mechanical Seal ?
Classification of Mechanical Seal

26.
Unbalanced Type（A0>A) Balanced Type（A0<A)
Mechanical Seal ?
Classification of Mechanical Seal Pressure Range

27.
Rotating Type Stationary Type
Mechanical Seal ?
Classification of Mechanical Seal Spring Location

28.
Inside Type Outside Type
Leaking to inside Leaking to outside
Mechanical Seal ?
Classification of Mechanical Seal Installation Location

29.
Bellows Type
V-Packing Type O-Ring Type
Working Performance
More
excellent
Mechanical Seal ?
Classification of Mechanical Seal Secondary Seal Design

30.
Multi Spring Type
Single Spring Type
Bellows Type
Mechanical Seal ?
Classification of Mechanical Seal Spring Design

31.
Holding from both
ends
Floating via O-Ring
Float Type
Press Fit Type
Clamp Type
No both ends holding
Based on ISO,API
Mechanical Seal ?
Classification of Mechanical Seal Stationary Ring Design
Keeping the flatness of the Seal Face
More
excellent
Flexibility

32.
Single Type
Double Type Tandem Type
Mechanical Seal ?
Classification of Mechanical Seal Arrangement
For high viscosity,
deadly poison
application
For emission control
(BTX,LPG etc)

33.
Non-Cartridge Type
Unitized Type
Separated Type
Easy
Installation
Mechanical Seal ?
Classification of Mechanical Seal Assembly Design

34.
Mechanical Seal Cartridge Seal Type
Mechanical Seal Cover
Sleeve
Stationary Type
(L9UC Type）
Mechanical Seal ?
Cartridge Seal Type?
Mechanical Seal

35.
Outside Mounted
Inside
Mounted
Cartridge Type
Mechanical Seal ?
assification of Mechanical Seal Assembly Design
Easy
Installation