Series STFLO Stainless Steel Flowmeters Specifications - Installation and Operating Instructions

Series STFLO Stainless Steel Flowmeters Specifications - Installation and Operating Instructions
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Page 1
Bulletin F-41-STFLO
Series STFLO Stainless Steel Flowmeters
Specifications - Installation and Operating Instructions
LABEL SEE
DETAIL 1
LABEL, SEE
DETAIL 1
10-21/32
[270.78]
2-11/16
[68.07]
4-1/32
[102.25]
LABEL, SEE
DETAIL 2
15-21/32
[397.28]
LABEL
SEE
DETAIL 2
2-13/16
[71.37]
OUT
OUT
4-1/2
[114.38]
3/4 NPT
Ø2-15/32
[62.99]
Ø4
[101.85]
IN 3-23/32
[94.23]
5-11/16
[144.65]
Ø1-11/32
[34.29]
2-3/4
[69.95]
IN
1-1/2 NPT
1-1/2 NPT CONNECTION
3/4 NPT CONNECTION
3
[76.20]
2-1/8
[53.59]
3
[76.20]
LABLE, SEE
DETAIL 1
LABEL, SEE
DETAIL 2
4-1/2
[114.30]
LABEL, SEE
DETAIL 1
LABEL, SEE
Ø2-3/4 DETAIL 2
[Ø69.85]
3-9/16
[90.43]
3-7/8
[98.55]
3/4 FLANGE CONNECTION
DWYER INSTRUMENTS, INC.
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46361, U.S.A.
6-13/16
[172.97]
Ø3-7/8
[Ø98.55]
5
[127.00]
3-11/16
[93.73]
Series STFLO Stainless Steel Flowmeters are ideal for dirty or
opaque fluids, high temperature and high pressure service and
harsh environments, specifically steam applications.The direct
reading scale provides ±2% accuracy. Flowmeters can quickly be
disassembled without removing the body from the pipeline for
easy cleaning.
3-1/2
[88.91]
4-31/32
[125.98]
5
[127.00]
1-1/2 FLANGE CONNECTION
SPECIFICATIONS
Service: Compatible with liquids and gases.
Wetted Material: T316 SS, Alnico magnet, Geothermal EPR Oring.
Temperature Limits: See chart on page 7.
Pressure Limits: See chart on page 7.
Accuracy: ±2% full scale.
Repeatability: ±0.5% of indicated flow rate.
Process Connections: 3/4˝ or 1-1/2˝ female NPT, optional flange
connections.
Scale Length: 3/4˝ models: 3.2˝ (8 cm); 1-1/2˝ models: 5.2˝ (13 cm).
Weight: 3/4˝ NPT models: 5.75 lb (2.6 kg); 1-1/2˝ NPT models: 14
lb (6.4 kg). 3/4˝ Flange: 9.75 lb (4.4 kg); 1-1/2˝ Flange: 22 lb (10 kg).
Phone: 219/879-8000
Fax: 219/872-9057
www.dwyer-inst.com
e-mail: [email protected]
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SAFETY PRECAUTIONS
Personnel safety should be considered before
pressurizing and operating the system. There are
numerous possibilities for error in system operation and
maintenance as well as component installation. Because
human eyes must necessarily come into close proximity
with the flowmeter to read it, Dwyer Instruments, Inc.
recommends that safety shielding such as a sheet of
transparent, high impact material be used in front of the
meter. If hazardous, toxic, or flammable fluids are being
metered, recommended safeguard should include
methods to protect personnel from splash or rebound. A
method of quick, safe removal of dangerous fluids should
also be included.
INSTALLATION
PREPARATION: Series STFLO Stainless Steel Flowmeters are
ready to install as-is, although the reading scales may need
repositioning so the scale is visible after installation. First, remove
the protective caps from the connection ports. Also, remove the
plastic tubing above the inlet cap in the meter core tube! This
tubing blocks the float assembly in place during shipment. Check
that the float moves freely within the core tube, and that no
packing materials are in the meter.
RECOMMENDED PIPING
Series STFLO Stainless Steel Flowmeters generally have no
special straight run or other piping requirements. Inlet piping
should be the same size as the meter connection. Some effect on
meter accuracy may occur at high flow velocities if inlet piping
guidelines are violated. Please refer to the table on the next page.
When installing on different size pipe, use standard pipe adapters
and come into the meter inlet with a nipple 8 diameters long of the
same size for greatest accuracy. Control valves should be
mounted on the outlet side of the meter. The use of a three valve
manifold around the meter is suggested, as it allows uninterrupted
process flow while the meter is being cleaned.
PLUMBING-IN
While the flowmeters should be vertical, exact plumbness is not
necessary. A general rule is that if the meter appears plumb, it is
close enough (even if off by 10º, the predictable reading error is
usually less than 1%). Pipe should be cut to proper lengths to
avoid stress on the meter. Avoid over-tightening, and do no use
wrenches on the body or reading scales. If using solvents in the
vicinity of reading scales, the scales should be removed until
fumes clear.
SURGE & WATER HAMMER PREVENTION
Operating Limits are for non-shock conditions only. Flowmeters
are more accurate and less likely to be damaged when the fluid
flow is smooth. Water hammer is a hazardous phenomenon and
should be eliminated from any fluid system. Water hammer is a
series of pressure shocks create by a sudden change in the flow
velocity of liquid in a pipe. This sudden change, often caused by a
fast acting valve or starting, stopping, or change in speed of a
pump, generates an immediate rise in pressure that sometimes
makes a noise similar to striking the pipe with a hammer. The
pressure wave is transmitted from the source throughout the
system, subjecting every component to the sudden shock.
Pressure returns to normal only when a larger vessel or pipe
section is reached, the energy dissipated thru friction and pipe
expansion, or some component ruptures. Rupture of piping,
valves, flowmeters, or other components have obvious safety
ramifications that must be addressed.
SURGE CHAMBERS & ACCUMULATORS
Flowmeters are more accurate and less likely to be damaged
when the fluid flow is smooth. If the meter must be installed on a
line where reciprocating pumps causing pulsation are used, surge
chambers, accumulators, or desurgers are strongly suggested to
dampen the shock wave. This is a good, general practice for all
flowmeters.
READING SCALES ROTATION
Series STFLO Stainless Steel Flowmeters use magnetically-linked
ball indicators and the scale may be positioned over approximately
a 300˚ range. However, the magnet position must also be changed
accordingly, requiring removal of the reading scales (see
“Disassembly”). On standard STFLO Stainless Steel Flowmeters
as depicted in Figure 1, the magnet slides out of the carrier at the
top of the float assembly. The screw holding the carrier to the float
may be loosened to allow rotation of the carrier toward the desired
scale location. Re-tighten the screw (thread sealant is
recommended), replace magnet, and reassemble the meter (see
“Assembly”). Verify that the ball indicator has been “captured” by
the magnet. If not, rotate the reading scales until the ball is
“grabbed” by the float magnet.
SEC A-A, TOP VIEW
A
A
MAGNET
METAL
PRESSURE
TUBE
BALL
INDICATOR
SNORKELGUIDE
READING
SCALES
PHENOLIC
RACEWAY
FIGURE 1
STARTUP
System flow should be started with the bypass valve open and
meter inlet and outlet valves closed. After the system is operating,
open the meter inlet valve gradually to equalize internal pressure.
Then slowly crack meter outlet valve and wait for float to stabilize.
Finally, slowly open the meter outlet and/or flow regulating valve all
the way and close the system by-pass valve.
AVOID SUDDEN SURGES THAT CAUSE THE METER
FLOAT TO SLAM INTO THE TOP OF THE READING
SCALES!
Although not essential, the meter reading scales should be filled to
a level above the float on liquid systems. The snorkel tube (present
in most standard models) allows escape of entrapped gases
except for a small pocket in the upper end which helps cushion
hydraulic shock. To assure proper filling and to flush any foreign
particles from the meter, operate the system at full flow briefly at
startup.
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READING FLOW
Read flow directly from the scale as the number nearest to the
center of the ball indicator.
CORRECTING READINGS FOR NEW LIQUID CONDITIONS
Qa = Qs
COMPENSATING FOR SYSTEM CHANGES
To find the correct flow reading for a system whose fluid conditions
vary from those for which the meter is scaled, use the conversion
equations provided. The most practical method of applying the
formulae is to calculate a conversion factor for the new system
condition and multiplying the scale reading by that factor. In the
problems to the right, “Q’s” has been assigned a value of “1” to
determine the conversion factor. (Dwyer Instruments, Inc. can
provide special scales at additional cost for other fluids and/or
units.)
CAUTION: DO NOT OPERATE THE FLOWMETER ON A
SYSTEM EXCEEDING THE OPERATING LIMITS OF THE
UNIT. WHEN CHANGING OPERATING CONDITIONS, MAKE
SURE THAT THE NEW SYSTEM CONDITIONS ARE WITHIN
THE FLOWMETER OPERATING LIMITS, AND ALL WETTED
MATERIALS ARE COMPATIBLE WITH THE FLUID.
Ps(Pf-Pa)
√ Pa(Pf-Ps)
or Qa = Qs
ds(df-da)
√ da(df-ds)
Where:
Qa=Actual flow, GPM (or same units as scale)
Qs=Meter reading from scale, (scale units)
ps=Specific gravity of calibration liquid related to water in std.
atmosphere at 70˚F being 1.00
pa=Specific gravity of metered liquid, same base
ds=Density of calibration liquid, lbs/ft3
da=Density of metered liquid, lbs/ft3
pf=Specific gravity of meter float
df=Density of the meter float as per Table below
FLOAT SPECIFIC GRAVITIES/DENSITIES
Material
pf
df
Stainless Steel
8.05
501.1
EXAMPLE: Using a standard stainless steel meter scaled for water
(ps = 1.00), what is the conversion factor for an oil with a specific
gravity of 0.85?
Qa = 1.00 x
1.00 (8.05 - 0.85)
√ 0.85 (8.05 - 1.00)
=1.11
Thus, actual flow of the oil would be the observed scale reading
times 1.096.
MAXIMUM FLOWS (WITHOUT EFFECTING ACCURACY)
FOR UNDERSIZED PIPES CONNECTED DIRECTLY TO FLOWMETER INLETS
PIPE
NPS
1/4
3/8
1/2
3/4
1
1-1/4
1-1/2
2
2-1/2
3
DATA
(ID)2
0.132
0.243
0.387
0.679
1.100
1.904
2.592
4.272
6.096
9.413
MAX. *
GPM LIQ.
1.72
2.98
4.74
8.31
13.47
23.32
31.74
52.29
74.56
115.2
ATMOS.
0.864
1.59
2.53
4.44
7.20
12.5
17.0
28.0
39.9
61.6
MAX. SCFM AIR @ †
50 PSIG 100 PSIG
3.80
6.74
7.00
12.4
11.1
19.8
19.5
34.7
31.7
56.1
58.8
97.2
74.6
132
123
218
176
311
271
480
200 PSIG
12.6
23.2
37.2
64.9
105
182
248
408
582
804
* Data per Cameron Hydraulic Data. Based on 5 FPS max. liquid velocity having no effect on flowmeters accuracy if the inlet pipe is smaller than the
meter connections.
† SCFM=0.445 x (psig + 14.7) x (ID)2. Based on 20 FPS max. air velocity having no effect on flowmeters accuracy if the inlet pipe is smaller than the
meter connections.
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CORRECTING READINGS FOR NEW GAS CONDITIONS
Qg = Qs
Pg x Ts x Ps
√ P xT xP
s
g
g
Where:
Qg=SCFM, corrected to new conditions
Qs=SCFM read on meter scale
Pg=Operating pressure, psia (psig + 14.7)
Qs=Pressure stated on scale, psia (psig + 14.7)
Tg=Operating temperature, absolute (˚F +460)
Ts=Temperature stated on scale, absolute (˚F + 460)
Pg=Specific gravity of metered gas
Ps=Specific gravity stated on scale
EXAMPLE: If using a standard meter scaled for SCFM Dry Air @
100 psig, 70˚F on argon (SP. GR.=1.378) at 50 psig, 100˚F, what
would the conversion factor be?
Qa = 1.00
64.7 x1.00 x530 = 0.622
√ 114.7 x1.378 x560
Thus, actual flow of the argon would be the observed scale
reading times 0.622.
STEAM
Series STFLO flowmeters are recommended for use with vapors,
especially steam. The conversion factor may be determined with
the following formula:
5.879
Mfh = Qm _______
√Sv
Where:
Mfh=Actual flow, lbs/hr.
Qm=Meter scale reading, Std. (SCFM Dry Air @ 100 psig, 70˚F)
Sv=Specific volume of media (from steam table)
EXAMPLE: When using a standard gas meter scaled from SCFM
Dry Air @ 100 psig, 70˚F, what is the conversion factor for lbs/hr.
steam at 50 psig, 300˚F?
Mfh =
5.879
√6.727
Thus, actual flow of steam in lbs/hr. would be the observed scale
reading times 2.267.
VISCOSITY CONSIDERATIONS
Each liquid flowmeter has so-called “Viscosity Immunity Ceiling”
(V.I.C.). Usually, if the viscosity of the metered liquid is less than the
V.I.C., the meter will be influenced significantly, and must be
calibrated for that viscosity. Effects of viscosity on a given
flowmeter are not always predictable. Two apparently similar
liquids with comparable densities and viscosities may impact
meter calibrations quite differently. The table below provides
general guidelines for the typical maximum viscosity for meter
models without affecting accuracy.
AVERAGE V.I.C., CENTISTOKES, FOR STANDARD
“THRU VIEW” FLOWMETERS
100% GPM,
3/4” METERS
CTS
100% GPM,
1-1/2” METERS
CTS
0.54-0.80
1.20-2.60
3.80-7.00
10.0-23.0
3
7
15
25
11.0-15.0
21.0-35.0
50.0
70.0-120
50
100
250
500
MAINTENANCE
Upon final installation of the Series STFLO Stainless Steel
Flowmeters, no routine maintenance is required. A periodic check
of the system calibration is recommended. The Series STFLO
Stainless Steel Flowmeters are not field serviceable and should be
returned if repair is needed (field repair should not be attempted
and may void warranty). Be sure to include a brief description of
the problem plus any relevant application notes. Contact customer
service to receive a return goods authorization number before
shipping.
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1. Remove the reading scale by removing the two set screws in
the black rings attaching the reading scale to the sight tube. Lift
the reading scale up and off of the meter. Set the screws aside
where they will not be lost.
METER DISASSEMBLY
SPIRAL RETAINING
RING
INNER FLANGE
RING
2. Using a screwdriver, carefully pry the notched end of the spiral
retaining ring out of the body groove. Move the screwdriver blade
under the ring- the action is very much like putting a key on a key
ring. Continue until the entire spiral ring has been removed from
the groove (please see the photo below).
READING
SCALE
SIGHT TUBE
ASSEMBLY
MAGNET(S)
STATIC O-RING
SEAL
CORE TUBE / FLOAT
ASSEMBLY
3. Using hands only, pull the sight tube straight up out of the body
with a slight twisting motion, lifting it clear of the body and snorkel.
The inner flange ring will lift off with the sight tube.
4. Remove the float assembly by lifting it up and away from the
snorkel. The core tube assembly may then be lifted out. If stuck,
CAREFULLY pry at the top of the slot with a brass rod, taking care
not to damage the body or core tube. The spider ring and O-ring
will come out with the core tube. If the core tube is stuck, try
removing the metal spider ring first (please see the photo below).
FIGURE 2: PARTIALLY EXPLODED DRAWING OF SERIES
STFLO STAINLESS STEEL FLOWMETERS
It is not necessary to remove the flowmeters from the pipeline for
cleaning or replacing parts. The body remains plumbed into the
pipe, allowing easy service and even installation of the different
sensing elements to accommodate new flow rates or fluids. Figure
2 shows some of the major components. Step by step
disassembly and reassembly instructions and photos are included
in the following.
CAUTION: BE SURE PRESSURE IS FULLY VENTED AND FLUIDS
COMPLETELY DRAINED BEFORE DISASSEMBLING THE
FLOWMETER. DISCONNECT POWER TO ELECTRONIC
ACCESSORIES. WEAR SAFTEY GLASSES AND PROTECTIVE
CLOTHING IF THERE IS A CHANCE OF EXPOSURE TO
HAZARDOUS FLUIDS!
INSPECTION & CLEANING
Inspect parts for nicks, scratches, chips, wear, and contaminant
build-up. The edges of the core tube slot, ID of the core tube and
OD of the piston (largest section at the float assembly bottom) are
precision machined. Damage to these areas can destroy the
meter’s accuracy. Also inspect the O-ring, the bottom section of
the sight tube, and the inside of the upper body section. Damage
to these areas may result in leaking. Clean, rinse, and dry all parts
carefully, including the O-ring, preferably with a mild detergent and
water and a soft cloth or soft tube brush. If solvents are used,
make sure they are compatible with meter parts.
CAUTION: DO NOT SCRAPE
MATERIALS FOR CLEANING!
OR
USE ABRASIVE
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FLOWMETER ASSEMBLY
In general, replace all parts in reverse order of the disassembly.
1. Place the slotted meter tube into the body, aligning the “key” at
the bottom of the tube with the keyslot in the bottom of the body.
6. Slide the inner flange ring over the sight tube. When properly
seated, the top of the flange ring should be flush with the bottom
edge of the snap ring groove.
2. Place the spider over the meter tube with the “notched leg over
the snorkel tube or guide rod. Slide the spider down to the meter
tube’s shoulder.
3. Place the meter float in the meter tube, aligning the notch in the
indicator disk with the snorkel.
4. Seat the O-ring on the sight tube, lubricating it with a small
amount of service-compatible silicone grease or petroleum jelly to
facilitate replacement.
5. Using hands only, press the sight tube firmly down into the
meter body with a twisting motion. Be careful not to rock the sight
tube side to side and bend the snorkel tube/guide inward where it
might interfere with float movement. Rotate sight tube as
necessary for scale visibility and/or alignment of the raceway
screw.
7. Separate the coils of the spiral retaining ring, and insert one end
into the body groove. Wind the ring into the groove, making sure
the ring is properly seated. Then replace the ball indicator (the tip
of a screwdriver can be used to help locate the magnet), and
replace the raceway and raceway cover.
Slide the reading scale over the sight tube, aligning the top of the
black metal of the reading scale with the screw hole on the sight
tube. The reading scale should read zero. Use the set screws to
secure the reading scale in place. Verify that the indicator ball
moves with the magnet.
If new flow internals are used, the scale may have to be remounted
on the sight tube. Depending on the model type, this can be done
either by loosening the mounting screw, or reattaching the scale
with double sided adhesive (new flow internals are shipped with a
new scale).
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REPLACEMENT PARTS
Under proper care, there should be no need to stock replacement
parts. If the service or environment is quite harsh, or frequent meter
disassembly dictated, a spare O-ring may be desirable.
Otherwise, parts only need to be replaced if damaged. Any visible
damage to the entire surface of the O-ring or sight tube
(particularly from the bottom edge) indicates need for replacement.
To insure accuracy, the inside surface of the meter core tube, slot
edges, and OD of the float piston should be free of nicks, chips,
with no visible erosion of any surfaces. If abrasive particles are
suspended in the meter fluid, it may be desirable to keep
replacement core tube/float assemblies on hand (Dwyer
Instruments, Inc. may also be able to recommend a more
abrasive-resistant construction).
To order parts, include the model and serial number of the units
involved, and description of the part ordered. If converting the
meter to a new application, in addition to the model and serial
numbers, SEND DWYER INSTRUMENTS, INC. COMPLETE
APPLICATION DATA INCLUDING FLUID, MAXIMUM FLOW RATE,
MAXIMUM
AND
OPERATING
PRESSURES
AND
TEMPERATURES, AND APPLICATION PARTICULARS OR FLUID
CHARACTERISTICS. This information is essential for Dwyer
Instruments, Inc. to provide proper items, and verify that the new
application is within the operating limits of the flowmeter.
TEMPERATURE VS. PRESSURE, OPERATING LIMITS, SERIES STFLO STAINLESS STEEL FLOWMETERS*
METER SIZE
& MATERIAL
3/4” NPT
1-1/2” NPT
MAXIMUM NON-SHOCK WORKING PRESSURE, PSIG @ ˚F
0˚F (-18°C)
1000 (68.9)
800 (55)
70˚F (21°C)
1000 (68.9)
800 (55)
300˚F (148°C)
1000 (68.9)
800 (55)
350˚F (176°C)
990 (68.2)
790 (54.4)
400˚F (204°C)
970 (66.8)
780 (53.7)
450˚F (232°C)
950 (65.5)
770 (53)
500˚F (260°C)
930 (64.1)
760 (52.4)
600˚F (315°C)
900 (62)
750 (51.7)
*OPERATING LIMITS GIVEN ARE BASED ON WATER OR AIR. FOR MORE SEVERE SERVICE, CORROSIVE, AND OTHER MEDIA AND/OR ENVIRONMENTAL FACTORS, AN
ADDITIONAL CORRECTION FACTOR DOWN-RATING THESE LIMITS MAY BE REQUIRED. LIMITS ARE BASED ON TESTING AND PRACTICAL EXPERIENCE. POSSIBLE
EXTREME APPLICATIONS CONDITIONS CANNOT BE FORESEEN. THUS, DATA OFFERED ONLY AS A GUIDE. IT IN NO WAY CONSTITUTES A SPECIFIC RECOMMENDATION
OR WARRANTY EXPRESSED OR IMPLIED.
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TROUBLESHOOTING
USUAL CAUSE
SUGGESTED REMEDY
FLOAT HANG-UP:
Caused by particles, sludge, etc. (including failure to
remove the plastic tubing used to block meter float during
shipment) inside the core tube and/or sight tube holding
float. A bent snorkel tube/guide rod (usually caused by
careless disassembly or violent surges) may also be
causing float to stick. Violent surges may also unseat the
internals in extreme cases.
Remedies include tapping the meter gently to temporarily
dislodge the float, but if problem reoccurs, meter should
be disassembled & cleaned, and/or snorkel/guide rod
straightened. If hang-up caused by sludge or pipe scale,
clean lines & install a filter or other form of cleaner in supply
line. If surges have caused the internals to unseat, install a
desurger, accumulator, etc.
FLOAT BOUNCE:
Caused by pumping/compressor surges or other pulsation
sources, loose valve disks or similar mechanical
components, extreme violation of inlet piping
recommendations, or for gas applications, harmonics
commonly found in systems with low pressure, low density
gas.
Modification of piping, such as addition of a desurger,
receiver, accumulator, vibration eliminators, loops, hoses,
etc. between the source and meter should remedy the
problem. Severe vibration may ultimately damage the
meter, and should be avoided. If “bounce” seems to be
from some other source, or shocks such as “water
hammer” (a potentially dangerous condition), discontinue
using the meter and contact Dwyer Instruments, Inc.
LOSS OF BALL INDICATOR:
Caused either by rotating the sight tube without realigning
the float magnet, or sudden flow surges or shocks.
Check the ball alignment to magnet by removing the
raceway cover and using the tip of a small screwdriver to
locate the float magnet. Rotate the sight tube as required,
and replace raceway (or disassemble meter to change
magnet position if required). If the alignment is okay,
eliminate system shock or surges with desurgers or
accummulators.
APPARENT FALSE
READINGS, LIQUID
METERS:
Liquid density not according to calibration data (different
temperature or new liquid or liquid mixture), excessive
dissolved or suspended solids or gases, partial clogging of
core tube slot or foreign matter interfering with float
movement, or viscosity levels above the meter’s immunity
index (V.I.C.)
By determining the actual density (due to changes in
mixture, temperature, etc.), the correction formulae may be
applied. If dissolved gases are in the liquid, some
elimination means should be provided on the supply side
(also recheck all piping, as improper seals at connection
points are common sources of air in the liquid). If the
metered liquid is near the boiling point producing partial
“flash gas” at the meter, relocate the meter to point of
lower temperature and/or higher pressure, or cool lines
and/or increase system pressure. Note: It is potentially
dangerous to meter near the “flash point” of any fluid, and
this practice should be avoided. Consult Dwyer
Instruments, Inc. for recommendations. The previous
recommendations regarding cleaning the meter and/or
filtration will also solve problems due to dirt. If metering
liquids with high viscosities, consult Dwyer Instruments,
Inc. (may require special calibration). If none of these
causes seem to be present, contact Dwyer Instruments,
Inc. for assistance.
SYMPTOM
NOTE: If the meter is suspected of giving false readings,
and none of the causes mentioned is found, please advise
Dwyer Instruments, Inc. as to the method used in
determining the suspected flow “error”. Each Flowmeter is
individually calibrated by traceable methods, and carefully
inspected. There may be some error in checking the meter
against another standard.
APPARENT METER
READING MIGRATION
(reading changes but flow
appears constant):
Frequently caused by use of soft disc type valves, which
may need to be replaced with a valve more suited to flow
control. Can also be indicative of changing fluid conditions
(density, viscosity, etc.). Problems with other elements of
the flow system, including leaks, clogged filters,
pump/compressor wear, etc. may first appear as a change
in meter reading-one of the functions of a flowmeter.
Verifying the proper fluid conditions are known and
applying correction formulae as needed will remedy
problems associated with changing fluids. Cleaning,
servicing, and replacement and/or repair of other system
components may be required.
LEAKAGE:
If at the junction of the body and sight tube, it is indicative
of either (a) damaged O-ring (most common); (b) damaged
sight tube; or (c) damage to the gland section of the body.
It may also be caused by improper reassembly of the
flowmeter in the field.
If there is leakage at the pipe connections to the meter, it
is probably caused from over-tightening pipes on a prior
installation (or the initial installation).
Replace any damaged parts immediately, using the proper
assembly procedures indicated in this instruction and the
assembly detail drawings.
Remove the body and inspect for damage-if none is
visible, check pipe threads, reapply proper thread
lubricant/sealant, and reinstall. If leak persists, replace
meter body.
NOTE: Flowmeters are hydrostatically pressure tested before they are shipped. Dwyer Instruments, Inc. encourages you to contact your Dwyer Instruments, Inc. representative or
the factory with any questions regarding proper installation and operation of our flowmeters.
©Copyright 2008 Dwyer Instruments, Inc.
Printed in U.S.A. 10/08
DWYER INSTRUMENTS, INC.
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46361, U.S.A.
Phone: 219/879-8000
Fax: 219/872-9057
FR# R1-443701-00
www.dwyer-inst.com
e-mail: [email protected]
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