Veris Verabar Brochure

Verabar

®

Velocity Averaging

Flow Sensors

True Performance in

Flow Measurement

Superior Signal Stability
and Greater Resistance to Clogging

Clogging can occur in low pressure ports located in or near the partial vacuum
at the rear of the sensor. The Verabar design locates the low pressure ports

on the sides of the sensor, forward of the fluid

separation point and turbulent wake
area. This virtually eliminates clogging

and produces an extremely

stable signal.

Rough Surface Smooth Surface

± 1/2 Percent

3%

2%

1%

0%

-1%

-2%

-3%
0% 5% 10% 15% 20% 25%

Percent Blockage

Percent Deviation from the Published K

Air Tests
Water Tests

0.5 Percent
Error Band

Lower Drag and Extended Turndown

Golf balls fly farther because they have a dimpled surface

that lowers aerodynamic drag.

The grooves and roughness on the Verabar’s frontal surface

apply the same principle. This simple design feature relieves the

partial vacuum at the rear of the sensor, reducing the pressure drag.

This extends the accuracy and rangeability to very low velocities.

The Most Accurate and Reliable
Technology for Measuring Gas, Liquid
and Steam

Developed from aerospace technology, the
Verabar averaging pitot flow sensor provides
unsurpassed accuracy and reliability.
With its solid one-piece construction
and bullet shape, the Verabar
makes flow measurement
clog-free and precise.

The unique sensor shape
reduces drag and flow
induced vibration.
And the location
of the low
pressure
ports elimi­nates the
potential for clogging
and improves signal
stability.

Test Data Summary

From Veris Research…True Performance in DP Flow Measurement

In God We Trust…
All Others Bring Data

The unique and exclusive break­through in improved accuracy
derived from the development of
a verified theoretical model
predicts the Verabar flow
coefficients. This elimi-

nates the need for
calibration tests to
characterize the
flow coefficients.

Without such a model,

the uncertainty of the flow

coefficients is dramatically

increased and expensive

calibration may be required.

Empirical test data from indepen-

dent laboratories verified the theore-

tical model and flow coefficients as a

constant, independent of Reynolds number

and within ±0.5% of the predicted value. The

derivation of the theoretical model and test data

is published in the Verabar Flow Test Report (ED-100).

Unique Valve Head

Verabar offers a new concept…
built-in valves in the head of the
instrument.

This superior design:

• Simplifies installation and

maintenance.

• Lowers the

connecting

hardware

cost by
reducing the
number of
fittings.

Transmount

A Transmount flow system
is the first choice for all
liquids; and for gas and
steam applications, with
slight variations in pressure
and temperature.

Mass
Transmount

A Mass Transmount flow
system should be selected on
steam and gas applications
with variable temperature
and pressure.

Field Flow
Systems

Ready to install, the
Verabar can be ordered
with a manifold, transmitter
or local indicating
meter.

The Proof of Verabar Accuracy

Accurate Flow Coefficients

The true test of a flow measurement device is its ability

to repeat its published flow coefficient within its accuracy

band.

Verabar

has been

thoroughly

tested at

independent

flow laboratories

(all sensor sizes, in

multiple pipe sizes,

in gas and liquids).

Spring-Lock

Complete
Installation
in Less than
an Hour

Partial Insert

• Designed specifically for

high velocity cooling water
applications, large diameter
pipes, large vertical stacks
and buried water lines

• Extends 1/3 into pipe to

reduce procurement
and installation
costs— specifically
useful when a
hot tap is required

• Partial Insert hot

tap sensors can be
inserted/retracted with
no reduction in flow rate

Spring-Lock…
Offers a Superior Mounting
Method

This advanced, patented design ensures
the sensor remains sealed, locked and
pre-loaded to the opposite wall regardless
of changes in pipe diameter due to pres­sure, temperature or mechanical force.

This design has important advantages:

• Fugitive emission and leak prevention…

The Spring-Lock continually compen­sates for the differential in packing and
body growth rates due to increased
temperature.

• Increases sensor strength,

thereby eliminating the

need for an opposite wall

support. A locked, pre­loaded sensor is four
times stronger than
a non-preloaded,
cantilevered sensor.

• Other mounting methods

do not pre-load the sensor
or the packing seal and are subject to
increased sensor vibration, metal fatigue,
breakage and leakage.

0.74

.073

0.72

0.71

K 0.70

0.69

0.68

0.67

0.66
0 5 10 15 20 25

Velocity (fps)

Test Location: Utah water Research Laboratory

Test Data: November 13, 1991
Fluid: Water at 60 deg F

Meter Size: 6 inch, Schd 40, -10
Serial No: V1000.05.1

±1.0%

Visual load
indicator

Spring
travel

Compensates for
changes in pipe
diameter

Actual Flow Test

The Verabar offers the widest application range
of any flow sensor. It accurately measures gas, liquid
and steam.

High Pressure Design

2500# ANSI Class

6000PSI and 1000ºF

The Verabar’s versatile design lends itself to
a wide range of applications. Contact Veris
application engineering for
your special requirements.

Square and
Rectangular Ducts

Large Stacks and Ducts

Up to 21 feet
(6 meters)

Specialized Mounting

• PVC • Concrete

• FRP • Cast Iron Pipe

Regular Models — (Threaded Components)

Model Number Type of Mounting

Tube Fitting
V100 (Single Support)

V110 (Double Support)

Spring-Lock
V150 (No opposite

support required)

Hot Tap Models — (Threaded Components)

Screw Drive
V200

Low Pressure
Hand Insertion
V250

Hot Tap Models — (Flanged Components)

Model Number Type of Mounting

Screw Drive
V400

Low Pressure
Hand Insertion
V450

Flanged Models — (Flanged Components)

Flanged
V500 (Single Support)
V510 (Double Support)

Flanged Spring-Lock
V550 (No opposite

support required)

V100

Verabar Model Selector

Verabar Applications

V110 V150

V500 V510 V550

V200 V250

V400 V450

Gas Liquid Steam

Natural Gas Cooling/Chilled water Saturated
Compressed Air Boiler Feed Water Superheated
Combustion Air De-Mineralized Water Main Header
Hydrocarbon Gas Hydrocarbon Liquids Custody Transfer
Hot Air Cryogenic Distribution
Blast Furnace Gas Thermal Transfer Fluids Energy Studies

Extended Range Applications

Fast and Easy Model Selection

The easy-to-operate Veracalc computer program features:

• Flow Calculations: DP from flow rate, or flow rate from DP.

• Model Selection: Complete model selection from drop down menus.

• Structural Analysis: Verifies sensor strength at flowing conditions.

• Temperature and Pressure Limits: Error warnings if limits are exceeded.

The Veracalc PC program is available from your local representative,
the factory or it can be downloaded from our website at www.veris-inc.com.

Verabar Lowers Installed
Costs

Verabar can save you more than 60%
in installation costs over an orifice
plate in a 10” pipe.

The graph shows the total installed
cost by pipe size of the orifice plate,
the Verabar, and the resultant Verabar
savings. The most significant portion
of the savings is the reduction in the
linear inches of weld.

Savings in Weld Time Installed Cost Savings

Verabar Has the Lowest
Operating Costs

Verabar pays for itself in less than
a year.

The graph shows the yearly operating
cost savings and equivalent horsepower
savings of the non-constricting, low
permanent pressure loss Verabar
compared to the extremely constricting,
high permanent pressure loss orifice
plate. Savings are shown for gases,
liquids and steam— at typical design
velocities, by pipe size.

Verabar vs. Orifice Operating Cost Savings

Through Accuracy of Measurement, Low Installed and Operating Costs,

Verabar Proves Its Performance, Efficiency and Value.

Verabar Maintains Its

Accuracy

Orifice plates show long term
deterioration of accuracy.

The initial accuracy of the orifice
plate is ±1%. However, long term
accuracy deteriorates unless the plate
is periodically inspected. Senior, dual
chamber fittings are available to check
the plate without requiring system
shutdown, but such fittings are very
expensive.

Condition % Deviation

Wear of knife edge:

0.010” -2.2

0.020” -4.5

0.050” -13.1

Dirt and grease

deposits in pipe -11.1

Valve lubrication upstream:

one side of plate -15.8
both sides -24.0

Leaks around plate -8.2

Plate warpage -9.6

Orifice Plate Test Results

Florida Gas Transmission Company
conducted a test to quantify various
conditions which can result in inaccu­rate measurement. A partial list of the
results is shown:

Pipe Size (Inches)

10 20 30 40 48

$ 1,000

$ 500

$ 10,000

$ 5,000

$ 100,000

$ 50,000

Dollar
Savings

Verabar Installed Cost

Orifice
Installed Cost

Verabar Installed
Cost Savings

Natural Gas

Steam

Air

Horsepower

Savings @

$ 0.05/KWH

300
200

100

50

10

5

1

Pipe Size (Inches)

10 20 30 40 48

$ 1,000

$ 500

$ 10,000

$ 5,000

$ 100,000

$ 50,000

Dollar
Savings

Liquids

Valve lubr. (-24%)

Warpage (-9,6%)

63 inches
of linear welding

Only 4 inches
of linear welding

Wear (-13.1%)

Dirt & grease (-11.1%)

Leaks (-8.2%)

$

$

$

$

$

$

$

$

$

$

$

$

$

$

$

$

Aerodynamic-Shaped Sensors

Extreme aerodynamic shapes that
permit the stream lines to reattach are
subject to airfoil type lift forces. This
occurs when
the angle of
attack varies
due to sensor
misalignment,
or the direction
of the fluid
varies, as is
common in
industrial piping
with upstream
disturbances.

Result:

The lift forces
can cause an
unpredictable
shift in the low
pressure distribution, producing
inaccurate measurement.

Quality Assurance

Veris manufactures its own leak-proof,
solid one-piece sensor. Our primary
goal is to provide the highest quality
and most accurate sensor in the
industry.

This can result in a significant undetec­table loss in accuracy.

Verabar is designed to meet or exceed

applicable ANSI and ASME codes.
The Verabar is available to meet

B31.1,

B31.3, B31.8, NACE MR-01-75, etc.

Additional QA capabilities include
code welding, hydrostatic and other
non-destructive testing.

Why Average the Velocity
Profile?

Verabar averages the velocity profile
through multi-sensing ports which span
the entire pipe diameter. Other types of
non-averaging insert meters are SINGLE
POINT INSERT METERS (turbine, vortex,
magnetic, sonic, etc.). They assume a
“textbook: turbulent velocity profile, and
use a single “critical” point to infer an

average velocity. In actual industrial appli­cations, sensors are located downstream
of disturbances, such as elbows or valves,
which produce non-uniform velocity pro­files. This makes it virtually impossible to
locate a single point that represents the
average velocity.

Result: Inaccuracy ranging from ±10%
to ±20%.

Round Sensors

Round sensors produce unpredictable
accuracy. The original round sensors
were designed for economical fluid
balancing and did
not meet industrial
demands for
accuracy. Round
sensors have
a variable fluid
separation point
that causes an
unstable low
pressure distri­bution around
the sensor.

Result:

Inaccuracy in
excess of ±5%
and as high
as ±10%.

ISO 9001 Certified

Problems with Other Sensor Shapes

Diamond and T-Shaped Sensors

These sensors produce pulsating, noisy
signals. They improved accuracy by use
of a sharp edge to fix the
fluid’s separation
point. However,
this greatly
amplified the
vortex shedding
forces.

Result:

The sharp
edges generate
extreme vortices,
causing sensor
vibration, pulsa­tions and a noisy
signal to the point
that transmitter
dampening and
signal averaging
are recommended.

Other manufacturers use a three-piece
sensor design that has no positive
mechanical method of maintaining
a seal between the tubes. Therefore,
temperature, pressure, vibration and
even manufacturing variations can

cause leakage between the chambers.

HL

HL

Verabar Round T-shaped

sensor sensor sensor

Textbook

profile

Actual profiles

Other

Verabar

Flow

Flow

Flow

Flow

Lift forces

Flow

Flow

Fixed separation
point

Variable separation
point

Control valve

Elbow

Low

Reynolds

Number

Location of average velocity

6315 Monarch Park Place •Niwot, CO 80503 USA •Phone: [phone] •Fax: [phone] VB-100 (2/09)
E-Mail: [e-mail] •Website: www.veris-inc.com Printed in USA

Verabar…True Performance in Flow Measurement

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