Siemens Milltronics MILLFLO User manual

MILLFLO
milltronics
Instruction Manual September 2003

© Siemens MilltronicsProcessInstruments Inc. 2003
Safety Guidelines
Warning notices must be observed to ensure personal safety as well as that of others, and to
protect the product and the connected equipment. These warning notices are accompanied
by a clarification of the level of caution to be observed.
Qualified Personnel
This device/system may only be set up and operated in conjunction with this manual.
Qualified personnel are only authorized to install and operate this equipment in accordance
with established safety practices and standards.
Warning: This product can only function properly and safely if it is correctly transported,
stored, installed, set up, operated, and maintained.
Note: Always use product in accordance with specifications.
Copyright Siemens Milltronics Process
Instruments Inc.2003.AllRights ReservedDisclaimer of Liability
This document is available in bound version and in
electronic version. We encourage users to
purchase authorized bound manuals, or to view
electronic versions as designed and authored by
Siemens Milltronics Process Instruments Inc.
Siemens Milltronics Process Instruments Inc. will
not be responsible for the contents of partial or
whole reproductions of either bound or electronic
versions.
While we have verified the contents of
this manual for agreement with the
instrumentation described, variations
remain possible. Thus we cannot
guarantee full agreement. The
contents of this manual are regularly
reviewed and corrections are included
in subsequent editions. We welcome
all suggestions for improvement.
Technical data subject to change.
MILLTRONICS®is a registered trademark of Siemens Milltronics Process Instruments Inc.
Contact SMPI Technical Publications at the following address:
Technical Publications
Siemens Milltronics Process Instruments Inc.
1954 Technology Drive, P.O. Box 4225
Peterborough, Ontario, Canada, K9J 7B1
Email: [e-mail]
For the libraryof SMPI instruction manuals, visitour Web site: www.siemens-milltronics.com

i
Table of Contents
Milltronics Millflo Solids Flowmeter ..............................................................................1
The Manual ..........................................................................................................................1
Specifications ......................................................................................................................2
Operation ..............................................................................................................................4
Components ....................................................................................................................................4
Horizontal Sensing Plate .............................................................................................................4
Negative Displacement ...............................................................................................................5
Installation ...........................................................................................................................6
Preparation .....................................................................................................................................6
Welding ............................................................................................................................................6
Load Cell Handling ........................................................................................................................6
Disassembly ....................................................................................................................................7
Installation of Shipping Stop ......................................................................................................7
Installation .......................................................................................................................................8
Millflo Outline and Dimensions ..................................................................................................9
Millflo Wiring ................................................................................................................................10
Calibration .....................................................................................................................................11
Applications .......................................................................................................................13
Material Feed......................................................................................................................................... 13
Flowmeter In-Feed Chutes ................................................................................................................. 15
Maintenance ......................................................................................................................18
Periodic Recalibration ................................................................................................................18
Checks ............................................................................................................................................18
Spare Parts ...................................................................................................................................18

ii

7ML19985CS01 Milltronics Millflo – INSTRUCTION MANUAL Page 1
Milltronics Millflo Solids Flowmeter
The Milltronics Millflo solids flowmeter is a low to medium-capacity flowmeter for
various product sizes, densities, and fluidities in restricted spaces. This low-cost compact
unit improves processing, increases operating efficiency, and helps provide significant
cost savings.
Operating with a microprocessor-based integrator package, the Millflo provides a display
of flowrate, totalized flow, and alarms. Outputs are 0/4 to 20 mA proportional to rate and
open collector output for remote totalization.
Dry bulk solids enter the flowguide producing a mechanical deflections as they strike the
flowmeter sensing plate before continuing through the process unhindered. A strain
gauge loadcell converts the horizontal force of the deflection into an electrical signal. The
integrator processes this into a display of flowrate and integrated total weight. The
process is immune to the effect of product buildup as only horizontal force is measured.
The Millflo features easy installation into standard pipe sizes, simple operation, and fast
and accurate flow response.
The Millflo is an accurate and repeatable force sensor and its performance depends on
the consistency of the material flow into the flowmeter and the quality of the installation.
The Manual
This manual covers the installation, operation, and maintenance of the Milltronics Millflo
solids flowmeter.
Please refer to this manual for proper installation and operation of any component of the
system to which the Millflo is applied. Adhering to the installation and operating
procedures will ensure a quick and trouble free installation and allows for the maximum
accuracy and reliability of your system. Because the Millflo is used in conjunction with an
integrator, refer to the integrator’s manual also.
If you have any questions, comments, or suggestions about the manual’s contents, please
email us at [e-mail].
For the complete library of Siemens Milltronics manuals,
go to www.siemens-milltronics.com.

Page 2 Milltronics Millflo – INSTRUCTION MANUAL 7ML19985CS01
Specifications
Nominal Sizes
• 100 mm (4"), 150 mm (6"), 200 mm (8"), 250 mm (10"), 300 mm (12")
Flow Rate
• 1 t/h to 230 t/h (1 STPH to 250 STPH) dependent upon range (see page 3) and product
bulk density
Product
• fine powder to 13 mm (1/2 inch) (see page 3)
Operating Temperature
• -40 to 65 °C (-40 to 150 °F)
Repeatability
•"0.2%
Accuracy
•"1% of full scale
Construction
• assembly:
• all welded housing and flowguide
•material:
• mild steel, painted
• optional: 304 (1.4301) or 316 (1.4404) stainless steel
• gasketing:
• silicone rubber
• sensing plate:
• 304 (1.4301) stainless steel
•optional:
• 316 (1.4404) stainless steel
• wear resistant coatings
• low friction coating
Load Cell
• stainless steel parallelogram
•temperature:
• -40 to 85 °C (-40 to 185 °F) maximum range
• 0 to 65 °C (32 to 150 °F) internally compensated
•output:
• 2 mV / V excitation at rated load cell capacity
Approvals
•CE
Weight
• see page 3

7ML19985CS01 Milltronics Millflo – INSTRUCTION MANUAL Page 3
Flowmeter Range
• the following ranges and load cell sizes have been specified
Maximum flowrates are based on material densities of 1.6 t /m3(100 lb./ft3).
Size (inlet) Min. Flow Max. Flow Particle
Size Load Cell Size Weight
4" 0 - 1 STPH
0 - 1 t/h
0 - 15 STPH
0 - 14 t/h 6 mm (1/4”) 2 or 5 lb. 20 kg (45 lb.)
6" 0 - 4.4 STPH
0 - 4t/h
0 - 38 STPH
0 - 35t/h 10 mm (3/8”) 5 or 10 lb. 32 kg (70 lb.)
8" 0 - 20 STPH
0 - 18 t/h
0 - 88 STPH
0 - 80 t/h 10 mm (3/8”) 10 or 20 lb. 90 kg (200 lb.)
10" 0 - 50 STPH
0 - 45 t/h
0 - 14 STPH
0 - 13 t/h 13 mm (1/2”) 20 or 50 lb. 113 kg (250 lb.)
12" 0 - 100 STPH
0 - 90 t/h
0 - 250 STPH
0 - 230 t/h 13 mm (1/2”) 100 lb. 136 kg (300 lb.)

Page 4 Milltronics Millflo – INSTRUCTION MANUAL 7ML19985CS01
Operation
Components
Horizontal Sensing Plate
The Millflo reacts to the horizontal component of force
created by the impact of material on the sensing
plate. The Millflo consists of two physical
components:
• the housing which includes the flowguide and
the outlet. It supports the sensing assembly
and guides the material flow.
• the sensing assembly, which includes the
sensing plate and the load cell.
material
flowguide
outlet
sensing
plate
load cell
The material travels down the flowguide, striking the
sensing plate and discharging through the outlet. The
force exerted on the sensing plate has both a vertical
and horizontal component. The design of the load cell
is such that it reacts to the horizontal component only;
the vertical component is ignored.
The sensing plate is displaced proportionally to the
material flow and is not susceptible to material build
up, so long as it does not bridge across to the housing.
Positive displacement of the load cell is limited by the
positive stop incorporated in the design of the load cell.
The displacement of the load cell is sensed by its strain
gauges. These convert the excitation signal from the
electronic integrator to produce a signal proportional
to material flow.
positive
stop
positive
displacement
horizontal
(force)
vertical
negative
stop

7ML19985CS01 Milltronics Millflo – INSTRUCTION MANUAL Page 5
Negative Displacement
A negative stop protects the load cell
against excessive negative displacement
which could functionally destroy it. The
negative stop is factory set so that the
output signal is limited to -20 mV when the
load cell is forced to travel in the negative
direction.
negative
displacement
Under no-flow conditions, the load cell/
sensing plate assembly is at rest at static
zero. Under this condition, the negative
stop should not contact the load cell, and
the output signal from the load cell will be
approximately -5 to 0 mV DC.
normal gap

Page 6 Milltronics Millflo – INSTRUCTION MANUAL 7ML19985CS01
Installation
Preparation
Prepare the site in accordance to the Siemens Milltronics drawing(s) provided. If no
drawings were provided or if there is confusion or doubt as to the Milltronics Millflo’s
installation, please consult your Siemens Milltronics representative.
When unpacking the Millflo, avoid subjecting the unit to mechanical shock. Excessive
mechanical shock can cause damage to the housing or load cell/sensing plate assembly.
The Millflo is generally shipped assembled with the sensing plate arrested to prevent
damage to the load cell.
The Millflo should be visually inspected for shipping damage. If damage is suspected,
contact your Siemens Milltronics representative and the shipping carrier.
When handling the Millflo, ensure the shipping stop is in place to secure the sensing
plate. Never subject the Millflo to shock by hitting it when trying to position it.
Welding
Remove the sensing plate and load cell before welding.
Load Cell Handling
The load cell tolerates very little negative displacement, or it may be functionally
destroyed. When handling the load cell, care must be taken not to force the gap open.
WARNING: Use extreme caution when arc welding in the area of the flowmeter to
ensure that no welding current flows through the flowmeter, risking destruction of
the load cell.
SUPPORT LOAD CELL THROUGHOUT HANDLING IN NON-VERTICAL POSITIONS.
IMPROPER HANDLING MAY FUNCTIONALLY DESTROY LOAD CELL

7ML19985CS01 Milltronics Millflo – INSTRUCTION MANUAL Page 7
Disassembly
Remove the load cell/sensing plate assembly from the housing prior to installation.
Installation of Shipping Stop
1. Remove the access cover, loosen
the shipping rod nuts as shown,
and then remove. Retain
calibration weight cable for use in
the calibration procedure.
2. Secure access door.
3. Remove and hold top cover/
junction box assembly. Avoid
applying stress to the load cell
cable connected through the
cover to the junction box.
4. Hold the load cell by the upper
cross piece. (See
Load Cell
Handling on
page 6) .
5. Remove load cell mounting
screws (2 places), and then lift
load cell/sensing plate assembly
up and out of the housing,
keeping the sensing assembly
vertical.
6. Set the assemblies aside in a safe
place.
top cover screws
(4 places) top cover /
junction box
assembly
top cover
flange
calibration weight
cable
load cell / sensing
plate assembly
access cover
shipping stop
(threaded rod)
loosen 2nd to
remove
shipping stop
loosen first to free
sensing plate
gasket
load cell
cable
load cell
mounting
screws
(2places)
IMPORTANT:While transporting, support the load cell / sensing plate
assembly as shown in Load Cell Handling on page 6.
Whenever the unit is to be moved, the
shipping stop should be reinstalled to
prevent damage to the load cell/sensing
plate assembly.
1. With the sensing plate resting in
its static position, insert
threaded rod as shown.
2. Tighten the two end nuts against
the housing to secure the rod in
place.
3. Turn the two opposing sensing
plate locking nuts toward the
sensing plate, maintaining the
sensing plate in its static
position. Tighten nuts to secure
sensing plate.

Page 8 Milltronics Millflo – INSTRUCTION MANUAL 7ML19985CS01
Installation
1. Set the Millflo housing in place ensuring that the flowguide and outlet gaskets are
correctly located.
2. The housing must be vertical within 1° in two planes 90° apart.
3. Bolt the flowguide and outlet flanges to the process piping.
4. If the load cell/sensing plate assembly was not removed prior to beginning the
installation procedure, the shipping stop must be removed. Refer to
Disassembly on
page 7 to remove the shipping stop.
If the load cell/sensing plate assembly was removed, reverse the disassembly
procedure to reassemble the load cell/sensing assembly into the housing and to
replace the cover/junction box assembly on to the top access flange. Do not reinstall
the shipping stop. Exercise caution while handling the load cell/sensing plate
assembly. Refer to the diagrams in the
Load Cell Handling section on page 6.
5. Wire the unit in accordance with Siemens Milltronics supplied connection diagrams
or as described in the integrator instruction manual.
(3) infeed pipe
mounting hardware
(1) gasket
Millflo
mounting hardware
(1) gasket
(3) outfeed pipe
(2)
NOTE: All items other than Millflo supplied by customer

Millflo Outline and Dimensions
C
C
C
D
60°
B
Q
R
C
A
J
FLOWGUIDE FLANGE E = No.of holes F = size of holes G = outside diameter H = inside diameter I = bolt circle diameter
clearance required for sensing plate removal
OUTLET FLANGE K = No. of holes L = size of holes M = outside diameter N = inside diameter P = bolt circle diameter
89 mm (3.5")
ref. 63.5 mm (2.5")
Flowguide and outlet: DIN versions are available. Flanges match ANSI patterns
Millflo Dimensions Flange (Infeed) Flange (Outfeed)
Size A B C D E F G H I J K L M N P Q R
100 mm
(4")
597 mm
(23.5")
203 mm
(8")
584 mm
(23")
338 mm
(13.3") 819 mm
(0.75")
229 mm
(9")
108 mm
(4.26")
191 mm
(7.5") 22.5°822 mm
(0.875")
279 mm
(11")
162 mm
(136")
241 mm
(9.5") 22.5°413 mm
(16.25")
150 mm
(6")
838 mm
(33")
254 mm
(10")
838 mm
(33")
435 mm
(17.11") 822 mm
(0.875")
279 mm
(11")
162 mm
(6.36")
241 mm
(9.5") 22.5°822 mm
(0.875")
343 mm
(13.5")
212 mm
(8.33")
298 mm
(11.75) 22.5°660 mm
(26")
200 mm
(8")
1168 mm
(46")
356 mm
(14")
1168 mm
(46")
577 mm
(22.72") 822 mm
(0.875")
343 mm
(13.5")
212 mm
(8.33")
298 mm
(11.75) 22.5°625 mm
(1")
483 mm
(19")
315 mm
(12.39")
432 mm
(17") 30°711 mm
(28")
250 mm
(10")
1321 mm
(52")
406 mm
(16")
1321 mm
(52")
693 mm
(27.3") 625 mm
(1")
406 mm
(16")
265"
(10.42")
362 mm
(14.25") 30°629 mm
(1.125")
533 mm
(21")
346 mm
(13.62")
476 mm
(18.75) 30°813 mm
(32")
300 mm
(12")
1575 mm
(62")
483 mm
(19")
1575 mm
(62")
838 mm
(33") 625 mm
(1")
483 mm
(19")
315 mm
(12.39 ")
432 mm
17" 30°829 mm
(1.125")
597 mm
(23.5")
394 mm
(15.5")
540 mm
21.25") 22.5°914 mm
(36")

Page 10 Milltronics Millflo – INSTRUCTION MANUAL 7ML19985CS01
Millflo Wiring
Millflo
junction box
wire by colour,
refer to integrator
manual
to Millflo
loadcell
red
(+ EX.)
black
(-EX)
white
(-SIG.)
green
(+Sig.)
shield
customer cable to integrator,
single load cell sensing or
non-sensing configuration. Refer
to integrator instruction manual

7ML19985CS01 Milltronics Millflo – INSTRUCTION MANUAL Page 11
Calibration
General
After the Millflo has been properly installed, calibration of the solids flowmeter system
should be done in conjunction with the integrator. Refer to the integrator instruction
manual for programming and calibration. The calibration is initially done using a test
weight. Material tests are recommended to achieve maximum accuracy.
Test Rate
The test rate is the material flowrate represented by the test weight. The test weight is
used to simulate the horizontal forces of the material hitting the sensing plate.
CALCULATION OF TEST WEIGHT AND TEST RATE
Select the test weight to represent a calibration point of 60% to 80% of the Design
flowrate based on the Millflo Calibration Constant of 45 g / T/H (tons per hour).1
Test Weight = Design Flowrate x Calibration Point x Calibration Constant
Test Rate = Test Weight
Calibration Constant
For Example:
If the Design Flowrate is 6 T/H, then
Test Weight 60%
= 6 T/H x 60% x 45 g / T/H
=162 g
Test Weight 80%
= 6 T/H x 80% x 45 g / T/H
= 216 g
Therefore the test weight should be between 162 g and 216 g.
If an available test weight of 200 g is used, then
Test Rate = 200g
45 g T/H
= 4.444 T/H
1. The Calibration Constant represents an average of a range of values covering
various material flow arrangements and materials handled by the Millflo. It is an
approximate value to be used in the calculation of the Test Rate. Through the
running of material tests, the Test Rate may be factored to obtain an optimum
value which should lie in the range of 50% to 100% of the Design Rate. The Test
Rate should never exceed 100% of the Design Rate.

Page 12 Milltronics Millflo – INSTRUCTION MANUAL 7ML19985CS01
Zero
Perform the zero calibration as described in the Calibration section of the integrator
instruction manual.
Span
1. Install the calibration pulley and bracket assembly to the flowmeter housing.
2. Hang the test weight over the calibration pulley using the test weight cable.
3. Perform the span calibration as described in the calibration section of the integrator
instruction manual.
4. After the span calibration has been completed, remove the test weight and pulley
assembly and store them.
Material Test
Calibration of the flowmeter by test weight is not a dynamic simulation and yields only an
approximate span calibration. Effective material flow, friction, and velocity can only be
reproduced by running actual material tests.
At least two 5 minute samples should be taken to ensure repeatability.
Refer to
Material Test and subsequent Factoring of the flowmeter sections of the
integrator manual.
Re-Rating
After material tests have been done and a decision is made to re-rate the Millflo at a
higher or lower capacity, (with 20% of the design rate specified at the time of purchase)
only the design rate parameter of the integrator needs to be changed. Following that, a
recalibration of the zero and span can be performed using the old test weight and test
rate. New material tests will not be required.
sensing plate
hook calibration access hole (remove plug
to access hook during calibration)
calibration
bracket
calibration pulley
cable
test
weight
mount bracket
using bolts
threaded into
Millflo wall
Millflo
housing

7ML19985CS01 Milltronics Millflo – INSTRUCTION MANUAL Page 13
Applications
Ideal material characteristics:
• low cohesion (flows well through chutes, similar to a liquid)
• low adhesion (does not stick to surfaces)
• low abrasion (will not wear out chutes, flowguide, or sensing plate)
• low causticity (will not damage internal flowmeter components)
Location
Materials with low moisture content generally have excellent flow and adhesion
characteristics. In processes where material moisture content varies, select a flowmeter
location where the moisture content is lowest.
Linings
• Sensing plate and flowguide non-stick linings are often used for flour (wheat),
starch, and material with similar characteristics.
• Sensing plate and flowguide abrasion resistant linings are often used for barley,
corn, soya beans, wheat, and material with similar hardness and particle mass.
Abrasive materials are best monitored at low velocity.
Material Feed
Ideal material in-feed characteristics
• constant and relatively low material velocity
• uniform material flowrate (not pulsing)
• negligible air flow through the flowmeter
• flowguide 17% to 50% full during operation
Feed Conditions
• A gravity-fed flowmeter generally provides accurate readings.
• A mechanically fed flowmeter may not provide a consistent feed, affecting
flowmeter performance. A consistent feed provides the most accurate readings.
• A reverse flowguide transition is preferred for high or variable velocity feeder
material discharges. (Refer to
Flowmeter Infeed Chutes on page 15.)
• A larger loadcell compensates for slight to moderate material pulsing at greater
than 1 pulse per second. If heavily pulsing feeder discharges at less than 1 pulse per
second, consult Siemens Milltronics or your local distributor.
• Use a flowmeter discharge chute suitable so that material cannot backup into the
flowmeter housing.
Note: For best performance and limited maintenance requirements, keep in mind
material compatability and flow patterns.

Page 14 Milltronics Millflo – INSTRUCTION MANUAL 7ML19985CS01
Screw Conveyor
Rotary Feeder
Bucket Elevator
Conveyor Belt
short pitch
double flight
• Most common type of material feeder
• Short pitch and/or double flight screws are
preferred. They reduce the batch size (and
increase the frequency) of the material
discharge pulses. Alternatively, the flights of a
standard screw may be cut back, ending before
the discharge opening.
• A reverse flowguide transition should be
considered for variable operating speeds or
constant speeds above 40 rpm.
• Provides an air seal between the upstream and/or
downstream process, and the flowmeter
• Required when the material is pneumatically
conveyed or flowmeter/process isolation is
required.
• Use a reverse flowguide transition for variable
operating speeds or constant speeds above 10
rpm.
• Common to grain applications
• Slow elevators (typically chain drive) often
produce heavily pulsing material discharge,
requiring feeder discharge damping. Generally not
suitable for the Millflo.
• Fast elevators (typically reinforced belt drive) often
require a deadbox to reduce material velocity. High
frequency of pulses make it suitable for the Millflo.
• Conveyor belts generally produce a non-pulsing
material discharge, ideal for flowmeter operation.
• A reverse flowguide transition (and/or material
discharge baffle) is often required for variable belt
speeds or constant speeds in excess of 1 m/s (200
feet/minute).
material
discharge
baffle

7ML19985CS01 Milltronics Millflo – INSTRUCTION MANUAL Page 15
Vibratory Feeder
Flowmeter In-Feed Chutes
The flowmeter in-feed chute delivers the material from the bin or feeder discharge to the
flowmeter flowguide. For optimal performance, in-feed chute is set to condition the
material flow to minimize the following:
•abrasion
• velocity variation
• feeder discharge trajectory variation
•pulsing
Feeder/Flowguide Transition
• Vibratory (pan) feeders produce a non-pulsing
material discharge.
• A reverse flowguide transition should be
considered for variable speed varieties.
motor
vibrating
pan
• A reverse flowguide transition reverses the
direction of the bin or feeder material discharge
before the material enters the flowmeter
flowguide.
• Reversing direction forces the material into a
desirable flow pattern, as opposed to permitting
material to be flung from the feeder directly into
the flowguide. This transition is especially
important for high or variable speed feeders.
• A forward flowguide transition maintains the
material in the same direction between the bin or
feeder discharge and the flowmeter flowguide.
• This transition is acceptable for a low and
constant velocity feeder.
• To use a forward flowguide transition for a high or
variable speed feeder application, install a baffle
plate.
baffle plate

Page 16 Milltronics Millflo – INSTRUCTION MANUAL 7ML19985CS01
Short Fall Chute
Long Fall Chute
Dogleg
Deadbox
• A short fall chute is when the bin or feeder
discharge to flowmeter flowguide fall is less than
0.6 m (2 ft) from the material infeed.
• The short fall chute present ideal measurement
conditions because material velocity due to gravity
is minimum.
• The chute center line and angle should coincide
with that of the flowguide for a distance greater
than or equal to the flowguide diameter (before
the flowguide inlet).
<0.6 m (2ft)
• A long fall chute is when the bin or feeder
discharge/flowguide fall is more than 0.6 m (2 ft)
from the material infeed.
• The long fall chute presents problematic
conditions because material velocity is increased,
increasing flowmeter component abrasion.
• Increased distances after chute-angle changes (to
settle material into desirable flow patterns) are
also required.
>0.6m (2ft)
• Use a dogleg to reduce the detrimental effect of
high or variable material velocity, and when a long
fall chute is used.
• For abrasive material, line the chute with an
abrasion resistant material or use an in-feed
deadbox.
• Install a deadbox where the chute angle changes,
causing the material to strike upon itself, rather
than on the chute surface
• Deadboxes conditions:
• high feeder discharge velocity
• variable discharge
• abrasive material
• Locate deadboxes where long-fall chute angles
change.