• Flush fluid should be connected to flow in
at the lowest point on the seal housing
and out at the highest point to vent air
pockets.
See drawing for suggested liquid flush
system (see figure 5a).
Double Mechanical Seal with steam
when:
No bacteria or contamination can be allowed
to enter pump, i.e. an aseptic system. A
steam barrier system must be installed as
follows:
• Wherever possible, sterile liquid e.g.
steam condensate should be used as a
flush. Condensate should be connected
to flow in at the lowest point on the seal
housing and out at the highest point to
vent air pockets.
• Where steam is essential, great care must
be taken with the design of pipework,
steam traps and controls.
• Steam must be clean, filtered and wet, i.e.
not superheated.
• The pressure of steam should be as low
as possible consistent with the desired
temperature
• Steam should be connected in at the
highest point on the seal housing and out
at the lowest point to allow any
condensate to drain from the lowest point
• See figure 6 for suggested steam
connection.
Silicon carbide on silicon carbide
seals are not recommended for steam
flushed applications.
Page 12
Hy~Line and Ultima Lobe Pumps
07/03
Figure 5a: High Pressure Liquid Supply
System for Double Seals
Figure 6:
Steam Barrier
Flush System
For Double
Mechanical
Seal
STEAM IN
1.5 bar max.
“Steam Traps”