Emerson KGA Installation And Maintenance Instructions Manual page 23

Clarkson Slurry Knife Gate ValVeS
KGA
fiGure 2 - OPen POSitiOn
B
f
open position
a) Gate positioned above seals, out of flow.
B) Matching elastomer sleeves seal against
each other under a high compression load.
C) Sleeves act as pressure vessel.
D) no metal parts in contact with slurry.
e) unobstructed port area eliminates
turbulence, minimizes pressure drop
across valve.
f) no seat cavity where solids can collect
and prevent full gate closure.
7. the operator of any valve should have an
understanding of the effects of opening/
closing the valve with regards to its role
in the overall piping system. Operators of
valves under pressure should take caution
to ensure that the valve is in good operating
condition prior to operating it under
pressure.
8. Certain processes contain hazardous and/or
otherwise unstable media. Care should be
taken in these circumstances to ensure the
operator is aware of the specific health and
safety risks associated with that medium.
9. When operating the valve stand clear of any
moving parts such as the stem and/or gate
assembly, use of gloves is suggested when
operating manual valves to minimize the
risk of injury.
10. all manually operated valves are designed
for hand input. Do not apply excessive input
torque via pipe wrenches, 'cheater bars',
or other devices. if a manual handwheel
actuated valve is difficult to operate due to
torque requirements, it is recommended
that the valve be supplied with or converted
to a bevel gear, air/hydraulic cylinder or
electric motor actuator.
fiGure 3 - ClOSeD POSitiOn
a
C
B
D e
D
Closed position
a) Gate travels through sleeves to provide
blind flange shut-off, allowing opportunity
for media to expel to atmosphere.
B) 100% isolation-bubble tight shut-off results
in absolutely zero downstream leakage.
C) When properly installed and maintained,
the KGa is designed to provide
man-safe isolation.
D) Double-seated design provides bidirectional
flow and shut-off.
e) Controlled stroke prevents gate from
penetrating too far, minimizing stress
on sleeve.
11. electric motor actuated valves should be
left in their factory set condition, unless
the system operating parameters dictate
a change. if changes are necessary, they
should be performed in small increments
using the lightest/lowest setting possible
to achieve the desired performance and
then the valve/actuator function inspected.
excess torque and/or thrust in the motor
settings may damage or lockup the valve.
12. Clarkson KGa valves are position seated and
should never be torque seated. Do not use
the motor torque settings to seat the valve.
13. Care should be taken to ensure that
electrical motors are wired correctly to the
power source. incorrect phasing of 3-phase
wiring may cause valve/motor damage.
a
C
e
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