Badger Meter Hydrometer User Manual

CM-6001-TM Manual

SERIES 12

VARIABLE AREA FLOWMETERS

INSTALLATION, OPERATION &

SERVICE INSTRUCTIONS

15555 North 79th Place

Scottsdale, AZ 85260

tel: [phone]

fax: [phone]

Email: [e-mail]

Web: www.cox-instruments.com

Contents

Section Page

I USE AND MAINTENANCE…………………………………… 1

1-1. Purpose ………………………………………… 1
1-3. Models ………………………………………….. 1
1-6. Variations Within Models …………………….. 1
1-9. Description …………………………………….. 1
1-24. Specifications ………………………………….. 4
1-27. Preparation for Use …………………………… 4
1-29. Installation ……………………………………… 4
1-30. Operation ………………………………………. 5
1-38. Maintenance …………………………………… 6
1-40. Cleaning Tubes and Floats ………………….. 6
1-42. Parts Replacement ……………………………. 6
1-44. Replacing Tube Gaskets ……………………... 6
1-48. Replacing Valves ……………………………… 7
1-50. Shipment ……………………………………….. 8
1-52. Storage …………………………………………. 8
1-54. Trouble Shooting ……………………………… 8
1-55. Back Lighting Maintenance ………………….. 9

Flowmeter Model Conversion Key 10

II PARTS BREAKDOWN………………………………………... 13

Figure 13. Burst Disc Assembly – Exploded View …… 13
Figure 14. Inlet Elbow Assembly …………………………. 13
Figure 15. Tube Assembly – Exploded View …………… 14
Figure 16. Worcester Valve and Handle Assembly ……. 15

SECTION I

USE AND MAINTENANCE

Section I

Paragraphs 1-1 to 1-10

1-1. PURPOSE.

1-2. The Series 12 flowmeter is an instrument for the accurate
and continuous measurement of the rate of flow for liquids
and gases at nominal pressures.

1-3. MODELS.

1-4. The Series 12 flowmeter is available in three basic
models; Model 124, Model 129 and Model 120. (Refer to
Flowmeter Model Conversion Key, Page 9). Each model is
available as a single stage or multi-stage flowmeter. Each
stage consists of a matched tube and float with a calibrated
scale and necessary mounting connections. A multi-stage
flowmeter consists of two or more matched tubes and floats,
normally of the same model together with scales and mounting
connections, assembled into a steel shell.

1-5. Bypass valves are required for most multi-stage
flowmeters to bypass the lower stages when operating in the
higher flow ranges, thus maintaining a normal pressure drop
over the entire flow range.

NOTE

On a maximum stage standard flowmeter of
any model, the pressure drop through the
flowmeter will not exceed 6 psig, except for
flowmeters with bypass orifice sections
where the pressure drop is approximately 8
psig.

b. Orifice valve and calibrated auxiliary bypass

orifice to increase the capacity of a particular
flowmeter.

1-9. DESCRIPTION.

1-10. In multi-stage flowmeters the top of each glass tube is

connected with the bottom of the next larger tube by a
copper tube at the rear of the shell. This provides a
continuous passage from inlet at the lower end of the
first tube to the outlet at the top of the last tube (see fig.

3). Each tube is fitted with a metal float which
positions itself in the tube according to the rate of flow.
Since the pressure drop across the float is constant
throughout the range of any particular tube, any change
in rate of flow will result in a relocation of the float to a
position where the annulus area is such as to maintain
this constant pressure drop across the float. Since the
tube is of an expanded taper, an increase in flow will
result in a rise in the float position and inversely a
decrease in flow will result in a lowering of the float
position. When the maximum capacity of a tube is
approached, the increased rate of flow affects the float
in the next tube. This sequence is continued through all
tubes until one of the floats comes to rest within the
limits of its scale at which point the rate of flow is read.
Tubes are calibrated and scales are engine divided to
read in pounds per hour, gallons per minute or other
units to fit specific requirements.

1-6. VARIATIONS WITHIN MODELS.

1-7. Multi-stage flowmeters usually consist of tubes of the
basic model as in paragraph 1-4, but to meet certain
requirements, some multi-stage flowmeters have been
produced with intermixed size 40, 90, 100 and 140 tubes.
Other requirements have resulted in incorporating size 60
tubes intermixed with one or more of the standard Series 12.
To correctly identify any tube refer to the number etched near
the top of the tube. This number consists of the flowmeter
serial number, tube size, and model number. For example,
12001-47 indicates flowmeter serial number 12001-47 and
tube size seven in the Model 124-300 group.

1-8. Other variations within models are:

a. Fluorescent backlighting for each and

convenience in reading flow.

1

Section I
Paragraphs 1-11 to 1-13

1-11. TUBES (fig. 2). Tubes are precision molded of
borosilicate glass with four float guides and tapered flutes
integral with the tube. The inner diameter across the guides is
the same from top to bottom but the inner diameter of the
tapered flutes expands logarithmically giving an increasing
flow area past the float as it rises. The guides confine the float
to the central axis of the tube and diminish swirls of fluid
passing through the tube. Tubes have flowmeter serial
number and tube size etched near the top of the tube.

NOTE

Tubes, floats, and scales are calibrated as a unit
and are not interchangeable. If a tube is broken,
a new tube, float, and scale must be ordered. An
unserviceable float can be replaced by fitting and
recalibrating a new float to the old tube.
Damaged scales can be replaced if flowmeter
serial number, tube number, and sizes are
furnished.

1-12. FLOATS (fig. 2). Floats are machined of a material
impervious to the fluid used and precisely fitted to the tube
making a matched assembly of float and tube. Floats are
provided with a short threaded stub extension for attachment
of a rod to facilitate removal or installation. Floats are etched
with the flowmeter serial number and tube size.

1-13. SCALES (fig. 4). Each tube with its float is accurately
calibrated and its scale graduated to agree with the calibration.
The 18-inch logarithmic type scale provides the same degree
of reading accuracy throughout the flow range. Scales are
made of plastic or aluminum and engraved with contrasting
figures. Scales are attached to adjustable support posts which

2

are located in drilled holes in front corners of the tube packing
glands and secured by screws. Scales are aligned with tube
index line by adjusting the support posts. Packing glands are
drilled at each side permitting scales to be mounted on both
sides if desired.

1-14. TUBE MOUNTING (fig. 15). Tubes are fitted into
upper and lower end castings and are held in position by
packing glands. The glands are tightened against gaskets to
prevent leakage. The end caps mounted on lower and upper
end castings contain float stops with springs.

1-15. TUBE CONNECTIONS. End casting fittings extend
toward the back of the instrument and are connected in series
by copper tubing. Bottom fittings are provided with bypass
valves when required. The fluid enters a manifold assembly at
the bottom and is then distributed as governed by the position
of the bypass valves. Outlet is from the top of the last tube.

Section I

Paragraphs 1-14 to 1-21

1-18. A 2-inch orifice ball valve is provided, in flowmeters, to
divert a portion of the flow through the calibrated orifice
increasing the flow range of the instrument. Flowmeters
incorporating a bypass orifice are provided with a special inlet
elbow to eliminate entrance effects.

1-19. INSTRUCTION PLATE. An instruction plate,
mounted behind the bezel window provides instructions for
operating the flowmeters and reading the position of the float.

1-20. SHELL. All tubes and fittings are mounted in a welded
steel shell. End castings are bolted to upper and lower
members. Shells are designed for flush panel mounting. A
bezel holding a safety glass window covers the front of the
instrument. A white enameled steel reflector panel is mounted
behind the tubes. Valve shafts extend through the bezel.
Handles are installed on the ends of the valve shafts.

1-16. The ball type bypass valve is manufactured by the
Worcester Valve Co. and is furnished in ¾, 1-1/4 and 2-inch
sizes.

1-17. The valve consists of a bronze body and ball with Buna
N seals to prevent leakage. One end of the handle assembly,
available in varying lengths, is connected to the valve by a
coupling while the bracket on the opposite end is connected to
the shell.

1-21. BURST DISC ASSEMBLY. A burst disc assembly can
be furnished to protect the flowmeter tube in installations
where the flowmeter might be subjected to excessive pressure
surges. This disc assembly is furnished as standard equipment
on any flowmeter incorporating a 48, 99, 109 or 148 size tube
and can also be ordered for any particular flowmeter. The disc
assembly is installed in a tee on the inlet side of the

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Section 1
Paragraphs 1-22 to 1-29

flowmeter and is designed to burst at a pressure lower than the
bursting pressure of the largest tube. The disc is rated to burst
at 85 psi. r 5 psi. This provides a bypass through which the
flow may be returned to the supply tank.

1-22. LIGHTS. Depending on size and number of stages
used, flowmeters can be equipped with explosion proof or
non-explosion proof fluorescent lights mounted behind the
tubes.

1-23. AIR CYLINDERS. Flowmeters can be equipped with
air cylinders to operate the bypass valves. Different cylinder
assemblies are used for 1-1/4 and 2-inch valves.

1-24. SPECIFICATIONS.

1-25. CAPACITY. Cox Variable Area Flowmeters Bulletin
CA 6001 provides information on the range and capacity for
all standard combinations of Series 12 Flowmeters.

1-26. MOUNTING DIMENSIONS. Cox Variable Area
Flowmeter Bulletin CA 6001 provides information on
mounting dimensions for all standard Series 12 Flowmeters.

1-27. PREPARATION FOR USE.

1-28. UNPACKING. Unpack instrument carefully. Parts of
this flowmeter are fragile and can be easily damaged. Check
all parts against packing slip to be sure that none are
discarded. Floats, 0.375-inch and larger, are packed
separately in a small container. Handle floats carefully.
Floats are fitted to the tubes with extreme accuracy and the
slightest damage may make them useless. Replace them in
original containers after checking until ready for their
installation.

1-29. INSTALLATION (fig. 6).

a. Flowmeter should be mounted in a vertical position and as
free from vibration as possible. The maximum allowable
position is approximately 5q off the center vertical centerline.
A position greater than 5q would tend to introduce about a 1 to
2% error in accuracy. Install special mounting stud (longer
threaded portion first) into holes drilled in customer’s panel.
Secure in place with lockwasher and standard hex nut. Install
meter shell onto studs and secure in place with special nut
with shoulder toward panel.

b. Clean inside of instrument thoroughly. Wipe reflector with
a clean cloth. The red index line on scale must align with red
mark on tube. Loosen set screws holding scale support posts
in packing glands and adjust scales if necessary. Install bezel
with window on front of shell by engaging clips on inside of
bezel in special mounting studs.

c. To avoid strain and transmitting vibration to flowmeter,
flexible hoses or lines should be installed between flowmeter
and service lines. If inlet and outlet unions cannot be
separated by the fingers, use two wrenches. All tubing joints
are soft soldered and strain on them should be avoided. With
suitable adaptor, connect flexible lines to unions and service
piping. Use two wrenches to tighten. A shut-off valve should
be installed in discharge line beyond the flexible connection.
This will prevent possible drainage of the instrument when
device being checked is disconnected. When furnished, install
pressure blowout disc assembly in inlet line to flowmeter.

d. A 25 micron filter should be installed on the inlet side of
the flowmeter. This will keep the flowmeter clean and keep
floats from sticking and collecting dirt. Collecting dirt adds
weight to the float which in turn changes flow rate reading.

4