Seametrics iMAG, Instructions Manual

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Tightening Flange Bolts
NOTE: Mating pipe flanges must be ANSI 150# full face (FF)
and/or raised face (RF).
1. Tighten flange bolts in an alternating pattern.
• Tighten left flange bolt-1 to 20% recommended
torque.
• Tighten right flange bolt-1 to 20% of
recommended torque.
• Repeat steps a and b for each bolt in an
alternating order, such as shown at right,
tightening to 40%, then 60%, then 80%, and then
100%.
2. Test for leaks.
3. If needed, tighten further in 10% increments until
leaking stops. DO NOT over-tighten. Over-tightening
can cause serious damage to the flow meter.
4. Recheck after 24 hours, adjusting if needed.
Suggested Tightening Sequence
Caution: Improper tightening sequence
can cause serious damage to the flow
meter.
• Do not tighten one side at a time.
• Do not tighten each bolt completely at
one time.
Santoprene Liner
Pipe Size ft-lb Nm
3” 25 34
4” 20 27
6” 42 57
8” 65 88
10” 73 99
12” 97 132
SUGGESTED FLANGE BOLT TORQUE
1
2
3 4
5
6
7
8
INSTALLATION and GROUNDING
Equalization and Grounding
Metal Pipe Installations. To equalize the electrical potential
of the fluid, the iMAG meter, and the surrounding pipe, secure
the flange plates (factory-installed on the equalization wire)
to both pipe flanges at one of the bolt holes, as shown below.
Be sure the lock washer fits between the pipe flange and the
flange plate. For the best electrical bonding, remove rust
and paint to expose clean, bare metal where the equalization
flange plate lock washer contacts the pipe flange. Connection
must be inspected periodically for corrosion to maintain the
necessary low resistance connection.
Plastic Pipe Installations. When the iMAG is installed in a
plastic piping system, grounding rings are recommended
(except 3” pipe size), especially in the presence of electrical
interference sources such as VFD pump drives. As shown in
the diagram below, the equalization wires should then be
connected to the grounding ring tabs instead of the flange
bolts as in metal piping installations. Where lightning is a
threat, or in severe electrical environments, an optional
connection to a nearby equipment ground or ground rod may
be advisable.
WARNING: ELECTRICAL SHOCK HAZARD
When the iMAG is installed in a plastic
piping system, or when externally powered,
the piping system must be grounded to meet
national and local electrical safety codes.
Failure to do so can result in electrocution.
Equalization Lug
Meter
Flange
Pipe
Flange
Gasket
Pipe Flange
Flange Plate
Lockwasher
Metal Pipe Metal Pipe
Meter Flange
Gaskets
Equalization Lug
Ground Clamp
(Exothermically weld when
corrosion is a concern)
8’ Ground Rod
Earth
Grounding Ring
Gaskets
Grounding Ring
Gaskets
#6, #8, or #12 AWG Stranded
Copper Ground Wire < 5’
Plastic
Pipe
Plastic
Pipe
Grounding Ring Part Numbers:
4” = 100876 10” = 100879
6” = 100877 12” = 103288
8” = 100878
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