The document discusses mechanical seals and their components. It describes single and double mechanical seals, as well as unbalanced and balanced mechanical seals. It also discusses tandem seals, barrier fluids, and calculating hydraulic balance percentage. Mechanical seals are used to prevent shaft wear by providing a replaceable surface that wears instead of the shaft. Barrier fluids are used to lubricate and cool mechanical seals, with different fluids used depending on the operating temperature range.
2. 2
Horizontal Surface wear Shaft wear
Equipment
Now it essential to find a solution to avoid shaft wear,
Such as finding another surface of another parts to be
worn but easy and cheap to be replaced, It is the
MECHANICAL SEAL
4. 4
Rotary Elements
1-Carbon ring
2-Snap Ring
3-O Rings
4-Springs
5-Sleeve
Stationary Element
Tungsten Carbide
ring
Or
Silicon Carbide ring
Equipment
Single mechanical sealSingle mechanical seal
7. 7
FACE AND SEAT AREA EQUAL 100% BALANCEFACE AND SEAT AREA EQUAL 100% BALANCE
F = P * A F = S * A
P * A = S * A
P = S
A = Contacted
Surface area
S = Contacted
Surface stress
P = Product+
Spring pressure
F = Acting force
S
P
=
100%
AP
Carbon ring
A
S
Stationary ring
8. 8
P
S A1 ( projected area of
P()product + spring
pressure(
)contacted surface stress(
=
A ( contacted surface
area(
120cm2
230cm2
=
Mechanical seal has the following data:
A = contacted surface area = 230 cm2
A1 = ( projected area of P) = 120 cm2
Calculate the hydraulic balance Percentage
SOLUTION
=.0 52*100=
52%
Hydraulic balance % is less than 65%
This Mechanical is prone to leak
Hydraulic balance % is less than 65%
This Mechanical is prone to leak