ITT TruBlue 710, Инструкция по установке, эксплуатации и обслуживанию

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Installation
Model 710 TruBlue Installation, Operation, and Maintenance Manual 30
Check Explanation/comment Checked
Check that the eccentric reducer at the
suction flange of the pump has the
following properties:
• Sloping side down
• Horizontal side at the top
See the example illustrations.
Suggested suction strainers are used.
Check that they are at least three times
the area of the suction piping.
Monitor the pressure drop across the
suction strainer.
An increased pressure drop across the
strainer of 5 psi (34.5 kPa) indicates
that the strainer should be removed
and cleaned.
After a period of time (24 hours mini-
mum) system flushing should be com-
plete and the suction strainer can be
removed. Suction strainers help to prevent debris from
entering the pump.
Mesh holes with a minimum diameter of 1/16 in.
(1.6 mm) are recommended.
Liquids with specific gravity less than 0.60 a
pressure drop across the suction strainer may be
due to ice buildup. Ice buildup can cause turbu-
lence, low pressure areas and pumpage vapor-
ization.
If more than one pump operates from
the same liquid source, check that
separate suction-piping lines are used
for each pump. This recommendation helps you to achieve a
higher pump performance and prevent vapor
locking especially with specific gravity of liquid
less than 0.60.
If necessary, make sure that the suc-
tion piping includes a drain valve and
that it is correctly installed. —
Assure adequate insulation is applied
for liquids with specific gravity less than
0.60. To assure sufficient NPSHa.
Liquid source below the pump
Check Explanation/comment Checked
Make sure that the suction piping is
free from air pockets. This helps to prevent the occurrence of air and
cavitation in the pump inlet.
Check that the suction piping slopes
upwards from the liquid source to the
pump inlet. —
If the pump is not self-priming, check
that a device for priming the pump is
installed. Use a foot valve with a diameter that is at least
equivalent to the diameter of the suction piping.
Liquid source above the pump
Check Explanation/comment Checked
Check that an isolation valve is in-
stalled in the suction piping at a dis-
tance of at least two times the pipe
diameter from the suction inlet. This permits you to close the line during pump
inspection and maintenance.
Do not use the isolation valve to throttle the pump.
Throttling can cause these problems:
• Loss of priming
• Excessive temperatures
• Damage to the pump
• Voiding the warranty
Make sure that the suction piping is
free from air pockets. This helps to prevent the occurrence of air and
cavitation in the pump inlet.
Check that the piping is level or slopes
downward from the liquid source. —
Make sure that no part of the suction
piping extends below the suction flange
of the pump. —
Make sure that the suction piping is
adequately submerged below the sur-
face of the liquid source. This prevents air from entering the pump through
a suction vortex.