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Gasket Spacers
Gasket spacers are used in conjunction with braided
packing rings to:
■
Close up the clearances around the inside diameter
of the packing set, keeping solid particles from pro-
gressing through the packing set along with the liquid
leakage
■
Act as a throttle bushing and reduce the pressure on
the outboard side of the spacer, in applications where
the leakage rate is relatively high
■
Keep the packing from extruding beyond the stuffng
box bottom, where there are excessive clearances
between the I.D. of the stuffng box bottom and the
shaft O.D. (This problem may occur through wear,
corrosion, or simply the way a piece of equipment is
manufactured)
In applications involving high stuffng box pressures
(particularly reciprocating pumps) gasket spacers are
also used to:
■
Reduce the amount of leakage that occurs through
the body of the braid, by forcing leakage to the I.D. of
the packing set and eliminating O.D. leakage
■
Keep the packing square, restrict packing movement,
and prevent packing rollover and premature failure
caused by excessive frictional forces
Gland Load
Garlock recommends using one of these two
methods to determine the proper gland load on a valve
packing set.
Percent Compression Method
This method simply determines the distance the set
should be compressed in order to achieve a seal. The
recommended percent compression varies with pack-
ing style.
■
9000-EVSP Simplifed
30% compression
QUICKSET
®
9001
30% compression
■
70#
/
ft
3
density GRAPH-LOCK
®
25% compression
70#
/
ft
3
density #98 sets
25% compression
■
90#
/
ft
3
density GRAPH-LOCK
®
20% compression
90#
/
ft
3
density #98 sets
20% compression
■
Garlock braided packing only 25% compression
In cases where the system pressure is very high
(over 2,500 psi or 72 bar), higher compression may be
required to achieve a seal.
Predetermined gland bolt torque method
This method determines a more precise gland load.
The bolt torque depends upon packing size, gland bolt
size, packing style system pressure, and the number of
bolts. The gland studs and nuts must be in good condi-
tion, cleaned with a wire brush and well-lubricated with
a suitable grease.
Use the following equation to determine the appro-
priate bolt torque:
BoIt torque =
(Bore dia.
2
- Stem dia.
2
) x (Gland bolt dia.) x (Load factor)
76.39 x (No. of bolts)
Where: Bolt torque is in ft. lbs.
Bore, stem, and bolt diameters are in inches
Load factor is in psi
The load factor is determined by the following:
■
For a 9000-EVSP Simplifed set, a 9001 QUICK-
SET
®
or a Style #98 and GRAPH-LOCK
®
set:
LF = 1.5 system pressure or 3,800 psi (whichever is greater)
■
When using any other Garlock packing:
LF = 1.5 system pressure or 5,500 psi (whichever is greater)
* Patent pending
Stealth Packing Set* Option
■
Optimal dry running situation—eliminate fush and
lantern ring
■
Combines Garlock Style 3530 GYLON
®
spacers
with Style 1304 or 1333-G cut rings
■
Contact Applications Engineering for details
Stealth Packing Set Spacer and Ring Arrangement
Style 1304
or 1333-G
Packing
Style 3530
Black GYLON
®
Spacers
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