Flowserve PLUS 5Q - Manual (Page 3)

NORDSTROM HYPREGUN-PLUS 5Q

Functions of Nordstrom Valve Sealants
1. Drop-Tight Seal - To secure an absolutely tight seal,
the film of the sealant works to form a seal between the
sealing surfaces of the valve. The seal is formed by sealant
transmitted through a system of passageways around the
valve port. With proper selection of sealant for your particular
service, the seal can be retained over a wide range of temper-
atures and pressures.
. Lubrication - Prevents metal-to-metal contact of the valve
sealing surfaces by filming over bearing irregularities. No
matter how finely ground a metal surface may be, the metal is
a series of tiny peaks and valleys. As one metal surface slides
against another, friction is set up and adhesion, shearing,
or plowing may result. A protective film of sealant over the
bearing area prevents metal-to-metal rubbing.
. Renewable Seat - There is no need to disassemble a
lubricated valve or remove it from service to replace mildly
damaged seats. Sealant, as a structural part of lubricated
valves, provides a flexible and renewable seat, eliminating
the necessity of force fit contact to effect a seal. For this
purpose, the sealant not only must have proper plasticity, but
also resistance to line fluids such as solvents and chemicals.
Sealant forms a seal between the sealing surfaces of the valve
even under pressure.
4. Plug Jacking - The fundamental operating principle of the
traditional lubricated plug valve design lies in the application
of Pascal’s Law. The law states that a unit pressure applied to
the liquid contained in a sealed vessel is transmitted to every
part of the liquid with undiminished force, thus multiplying
the force many times, depending on the area of the interior of
the vessel. The sealant, under pressure developed by sealant
injection, supplies the hydraulic means for lifting the plug
from its tapered seat when and if that force is needed to
free the plug.
Flow Control
Nordstrom Valves
Nordstrom Valves offers
more than twenty five
varieties of sealants
for plug, ball, and gate
valves. Stick and bulk
grades are available in
most formulas.