Ultrasonic measuring device
for material bed depth
Code word
Order number
AAT-Item
Contents
1
2
3
3.1
3.2
4
4.1
4.2
4.3
5
6
6.1
6.2
6.3
7
7.1
7.2
7.3
7.4
8
9
9.1
9.2Technical Data ......................................................................................1-1Safety ..........................................................................................................2-1Components and description of functionning ........................3-1Components .........................................................................................3-1Mode of functioning of the ultrasonic measuring transducer ..............................................................................3-4Transport and assembly ....................................................................4-1Transport and storage instructions ..............................................4-1Assembly .....................................................................................................4-1Measurement signals to the higher-level control system .................................................................................4-2Lubrication ...................................................................................................5-1Preparation for the test run .............................................................6-1Checks after assembly ...................................................................6-1Setting and first commissioning .........................................................6-1Operation .....................................................................................................6-1Maintenance ................................................................................................7-1Inspection ....................................................................................................7-1Servicing ...............................................................................................7-1Troubleshooting ....................................................................................7-2Repair ..........................................................................................................7-3Spare parts ..................................................................................................8-1Appendix .....................................................................................................9-1Technical drawings ...............................................................................9-1Subsuppliers' documentation ..........................................................9-1
1 Technical Data
NOTE
Information on the electrical equipment is contained in the separate electrical
documentation or in the subsuppliers’s documentation.
I nformation on the intended use
The ultrasonic measuring device for material bed depth is a component of the
roller mill.
Basic data
Year of manufacture
Type
Number
Type of protection
Operating temperature
Storage temperature
Power supply …
Permissible residual ripple
Current output
Set to
Voltage output
Power consumption
Transducer frequency
Response delay
Sensing range LE
Set measuring range, start A1 A1
Set measuring range, end A2 A2
Measuring range LM
Resolution at measuring range end
Reproducibility
Linearity
Temperature drift
Weight
Design
Length
EN-16052.060-F
Equipment connecting plug
Type
Length of the connecting cable
Maximum cable length
Supply devices
Reqd. current output of the meas. transducer supply devices
2 Safety
NOTE
Be sure to comply with the general safety instructions in the supplement
Important notes on the documentation.
Use
• The measuring device is exclusively intended for measuring the material bed
depth in the roller mill.
Be sure to comply with the instructions concerning the intended use in the
section Technical data.
Any use other than the intended use is forbidden. POLYSIUS AG is not
responsible for damage resulting from any use other than the intended use.
All other use is at the owner’s own risk.
POLYSIVS AG
The intended use also includes observance of the instructions in the opera-
ting manual and the maintenance instructions.
• •
Operation
•
• Do not make any alterations to the ultrasonic measuring transducers. Any safety checks before or during operation depend on the relevant national
regulations. The plant management is responsible for the performance and
recording of such checks.
Hearing protectors have to be worn in the roller mill building.
•
EN-16052.060-F
Maintenance
• Ensure that all machines and motors whose operation might endanger
persons or equipment are switched off and safeguarded against restarting for
the entire duration of the maintenance work.
Keep the measuring devices free of oily and combustible substances and
materials. Never use gasoline or other easily inflammable materials for
cleaning the measuring device.
Switch off the power supply to the electrical components before commencing
any maintenance work.
If you carry out electrical welding on any part of the machine, never conduct
the welding current through plain or antifriction bearings, other movable
connections or measuring equipment. Always directly connect the welding
current return lead to the part being welded.
Remount all protection devices when maintenance work has been finished.
Make absolutely sure that no persons are inside the plant component before
you properly close the inspection and service covers.
• • • •
3 Components and description of functionning
NOTE
The drawings in this manual are schematic representations for better understan-ding of the descriptions.
The function of the measuring device supplied by POLYSIUS AG is to measurethe space between the roller pair unit and the grinding table of the roller mill andthus determine the material bed depth. POLYSIUS
AG
3.1 Components
The ultrasonic measuring device essentially consists of the following compo-nents:
•
•
•
• the ultrasonic measuring transducers the connecting cables the reflection plates the fixing elements
EN-16052.060-F
Items shown in the drawing
A
B
C
D
E
1
2
3
4Hydraulic cylinder Piston rod Tie rod of the roller pair unit Roller pair unit Grinding table Ultrasonic measuring transducer Reflection plate Bracket for ultrasonic measuring transducer Connecting cable with plug 1.7Fixing nut
The bracket (3) for the ultrasonic measuring transducer and the reflection
plate (2) are components of the mechanical equipment of the roller mill. 3 2
Figure 1Ultrasonic measuring device for material bed depth
EN-16052.060-F
Items shown in the drawing of the ultrasonic measuring transducer
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
2Ultrasonic measuring transducer Ultrasonic transducer Evaluation unit Instrument amplifier Program plug connector with temperature sensor LED window LED Connection socket Fixing nut Reflection plate
angle of sound beam spread
measuring range αL M
3.2 Mode of functioning of the ultrasonic measuring transducer
After application of the operating voltage, the ultrasonic transducer (1.1) sends a
defined transmission pulse (Y). For a period of time (T) the ultrasonic transducer
(1.1) is now switched to reception and the incoming echo pulse (Z) is relayed to
the evaluation unit (1.2). This filters out the usable signal and calculates the
distance to the reflection plate (2) from the sound travel time. This measured va-
lue is converted into a load independent current in the series-connected instru-
ment amplifier (1.3).
1.1 Y 1.1 T Z
1.2
1.3
Reflection plate (2) 2
The reflection plate should be at least 100 x 100 mm in size and have a maxi-
mum surface roughness of 0.2 mm. 100*100 0.2mm
Figure 2Ultrasonic measuring transducer with reflection plate
EN-16052.060-F
Influencing variables
Temperature
As this unit is equipped with temperature compensation, the influence of the
ambient temperature within the permissible operating limits is negligible.
Humidity
The difference between dry air and saturated, humid air changes the measured
value by max. 2 %, proportional to the sound velocity alteration. 2% Air pressure
Normal air pressure fluctuations cause a sound velocity alteration and thus a
change in measured value of approx. 0.6 %.
0. 6%
Air streams
Under normal ambient conditions, the influence of air streams is very slight. In thecase of higher wind speeds, however, it is possible that significant measured
value falsifications could occur. These could, for instance, also be caused by
compressed air or powerful fans.
3.3Mode of functioning of the measuring device
To determine the material bed depth LMB in the roller mill, i.e. the distance
between the roller pair units (D) and the grinding table (E), the distances L1 and
L 2 between the hydraulic cylinders (A) and the associated piston rods (B) are
measured. As a roller pair unit (D) has two hydraulic cylinders (A), the arithmeticmean value has to be computed from the two raw measured values L1 and L2,
and the initial value L0 then has to be subtracted. This initial value results from
the arithmetic mean value of the two raw measured values L01 and L02 when theroller pair unit is in contact with the grinding table and the roller carrier is
horizontal (also see Figure 4 and Figure 5). L MB D E A B L 1 L 2 A L 1 L 2 L 0 L 0 L 01 L 02 L 01 L 02 4 5
As the roller mill has two roller pair units, two calculated values LMB (1) and LMB (2)are also displayed. Because the measuring principle is identical for both rollerpair units, the following description refers to just one roller pair unit.
L MB (1) L MB (2)
Dimension factor
For the calculated values to be indicated in millimetres, they have to be multipliedby the dimension factor KD . mm K D
L MB = material bed depth LMB =
The dimension factor K D is derived from the data of the
ultrasonic measuring transducer.
Measurement curve
I [mA]
20
4
LM s [mm]
A1A2
Figure 3Measurement curve of current over travel distance L M
l
s ===
=
=measuring range current output travel distance set measuring range, start set measuring range, end A1A2
see Sect. 1
EN-16052.060-F
Initialization
To enable determination of the initial value L0, the roller pair units (D) withhorizontal roller carriers must be in contact with the grinding table (E). The
required procedure, as well as further information, are described in the machinemanual Roller mill. L 0 (D) (E)
The initial value L0 is obtained via the arithmetic mean value generation from thetwo raw measured values L01 und L02. L 0 L 01 L 02
L01 + L02
2L0 =
This initialising value L0 is the reference point for measurement of the materialbed depth and is also used for wear determination by means of measuring. Storethis constant in the master control system. L 0
The material bed depth (LMB ) is calculated as follows:
L1 + L2
2LMB =- L0
and equals zero during the initialisation.
Items shown in the drawing of the initialisation
A Hydraulic cylinder
B Piston rod
C Tie rod of the roller pair unit
D Roller pair unit
E Grinding table
1Ultrasonic measuring transducer
2 Reflection plate
L 01
L 02
L MB
L 0====raw measured value 1 when roller pair unit in contact with table 1raw measured value 2 when roller pair unit in contact with table 2material bed depth Initial value
EN-16052.060-F
Figure 4Determination of the initial value
Grinding operation
After the initialisation, you can start up the mill in accordance with the Operating manual for roller mills. Due to the building up of the bed of material, the tie rods ofthe roller pair units (C) with the mounted reflection plates (2) are drawn out of thehydraulic cylinders (A). The distances between the ultrasonic measuring transdu-cers (1) and the reflection plates (2) increase by the distance L1 - L0 or, respecti-vely, L2 - L0.
2 C A 1 2 L 1-L 0 L 2-L 0
The material bed depth is now also computed via the arithmetic mean.
LMB =(L1 - L0) + (L2 - L0)
2=(L1 + L2)
2- L0
Items shown in the drawing of the grinding operation
A Hydraulic cylinder
B Piston rod
C Tie rod of the roller pair unit
1Ultrasonic measuring transducer
2Reflection plate
L 0
L MB
L 1
L 2====Initial value material bed depth raw measured value 1 1raw measured value 2 2
EN-16052.060-F
Figure 5Determination of the material bed depth
Wear
After some time of operation, system-inherent wear of the roller pair units and the
grinding track begins. The resultant reduction in size of the grinding rollers and
the grinding track can lead to incorrect measurements of the material bed depth if
initialisation is not repeated.
Compared to the first initialisation, the operating point is lower by the amount of
the total wear LV and, therefore, the material bed depth measurement is also
incorrect by this amount.
L V
The indicated value LMB ’ has to be corrected in accordance with the equation
L MB
L MB = LMB ’ + LV
The total wear LV can only be determined by means of a new initialisation in
accordance with
L V
L V = L0 - L0’
The procedure is described under Initialisation .
Items shown in the drawing of the wear determination
A Hydraulic cylinder
B Piston rod
C Tie rod of the roller pair unit
1Ultrasonic measuring transducer
2Reflection plate
L 0
L 0’
L V
L MB ====Initial value initial value after wear amount of wear material bed depth
EN-16052.060-F
Figure 6Determination of the wear
4
4.1 Transport and assembly Transport and storage instructions
The measuring device is transported completely packed.
When they arrive at the site, all parts must be inspected for transport damage and
stored so that they are protected against rain, soiling and damage.
Store the measuring device in well aerated buildings and protect it against moi-
sture.
4.2 Assembly
General notes
The following assembly instructions do not detail the individual steps for assemb-
ling the units, but rather give an overview of the work to be performed.
Changes in the planning of the plant during the processing of the contract may
lead to deviations from these assembly instructions.
NOT E
It is a prerequisite of our warranty that final assembly and assembly inspection are un-
dertaken by an assembly specialist from POLYSIUS AG.
POLYSIVS
AG
Careful selection of tools and appliances used and of the personnel is important for the
correct execution of the assembly work.
CAUTION
If you carry out electrical welding on any part of the machine, never con-
duct the welding current through measuring equipment, in order to pre-
vent damage to these parts.
Always directly connect the welding current return lead to the part being
welded.
EN-16052.060-F
Mounting the ultrasonic measuring transducer
You can mount the ultrasonic measuring transducer in any desired position. Ho-
wever, avoid mounting locations where heavy coatings of material, jets of water
or strong air streams (compressed air) are to be expected. Furthermore, be sure
to mount the ultrasonic sensors at a minimum distance of 1 m.
1m
Mount the ultrasonic measuring transducers on the provided brackets (3) on
the hydraulic cylinders (A) (see Figure 1).
A 3 1
The tightening torque for the fixing nuts (1.7) is 15 Nm.
1.7 15Nm
NOTE
If you screw the device into a threaded hole, it is possible that lead errors
may cause over winding of the casing. Fix the ultrasonic measuring trans-
ducer in through-holes using the supplied nuts.
Connect the position measuring devices with screened cables to the higher-
level control system of the machine/plant.
/
4.3 Measurement signals to the higher-level control system
The current output is permanently set to “live zero point“ and rising ramp.
The following signals are available at the terminals:
Terminal
1
2
3
4
Table 1Designation + operating voltage+ + voltage output+ - earth + current output+ + UB Value + 0 ... 10 V- UB , Gnd + 4 ... 20 mA
Max. load Current output
Voltage output
Table 2R L ≤ 500 ΩR L ≤ 1000 Ω
EN-16052.060-F
5 Lubrication
NOTE
This measuring device requires no lubrication.
/
EN-16052.060-F
6 Preparation for the test run
NOTE
It is a prerequisite of our warranty that the first commissioning is carried out in the
presence of and according to the instructions of specialists from POLYSIUS AG.
KRUPP POLYSIUS
AG
6.1 Checks after assembly
Before starting the first commissioning, check all parts of the plant according to
the list below. Take particular care that all material remnants, tools and assembly
aids are removed.
/
Check the ultrasonic measuring transducer for secure and correct mounting.
,
Check the reflection plate for correct alignment.
Check all connections for correct polarity.
Check all cables for damage and kinks.
6.2 Setting and first commissioning
Ultrasonic measuring transducers (1) are delivered in set and sealed condition.
Subsequent attempted resetting via the programming plug connector can dama-
ge the plug connector or the installed temperature sensor. Wrongly set or faulty
ultrasonic measuring transducers must be replaced.
Before starting the grinding operation, perform an initialisation of the measuring
device. Please take note of section 3.
3
6.3 Operation
When you have successfully concluded the first commissioning, the ultrasonic
measuring device is available for measuring the material bed depth during opera-
tion. Remember to carry out a correction when necessary, in order to take ac-
count of the system-inherent wear in the roller mill. Please take note of section 3.
3
EN-16052.060-F
7
7.1
No.
1Maintenance Inspection Work to be performed Check the ultrasonic measuring transducer for
dust deposits
Check the ultrasonic measuring transducer for
secure mounting
Check the connecting cables for damage
Frequency Weekly Monthly Monthly Comments 23
7.2
No.
1Servicing Work to be performed Clean dust off the ultrasonic measuring
transducer
Frequency Weekly Comments
EN-16052.060-F
7.3
Fault Troubleshooting Cause
Wire breakage
Elimination check plug connector withcable; replace if necessary
terminal connections
not O.K.
supply voltage
not availablecheck and fasten the terminalconnections put the power supply inorder
replace the ultrasonic
sensor
initialise the measuring
device Analog signal absent,
7.4 Repair
Before performing any repair work, switch off the power supply to all electricalcomponents.
Ensure absolute cleanliness at all times during the repair work in order to preventdirt from entering sensitive parts of the machine or plant.
CAUTION
After you have completed the repair work, you must check the mea-suring device again according to the section Preparation for first
commissioning and operation.
EN-16052.060-F
8 Spare parts
Notes for enquiring about and ordering spare parts
Dear Customer,
POLYSIUS AG strive to render your enquiring about and ordering of spare partsas easy, and as a consequence, as efficient as possible. For this purpose wehave prepared a table containing all data required by our spare parts departmentto ensure optimum processing in the most speedy and trouble–free manner.
Please copy the page with the respective table and mark those parts which yourequire with a cross in the column Order or Enquiry. Code word:
Item
1
4Designation Ultrasonic measuringtransducer 5 m connecting cable with
plug 5 Order-No.:Qty . Unit AAT-Item:Order Enquiry
EN-16052.060-F
9
9.1 Appendix Technical drawings Designation
Circuit diagram Drawing no. 9.2 Subsuppliers' documentation
Ultrasonic measuring transducer
EN-16052.060-F
Ultrasonic measuring device
for material bed depth
Code word
Order number
AAT-Item
Contents
1
2
3
3.1
3.2
4
4.1
4.2
4.3
5
6
6.1
6.2
6.3
7
7.1
7.2
7.3
7.4
8
9
9.1
9.2Technical Data ......................................................................................1-1Safety ..........................................................................................................2-1Components and description of functionning ........................3-1Components .........................................................................................3-1Mode of functioning of the ultrasonic measuring transducer ..............................................................................3-4Transport and assembly ....................................................................4-1Transport and storage instructions ..............................................4-1Assembly .....................................................................................................4-1Measurement signals to the higher-level control system .................................................................................4-2Lubrication ...................................................................................................5-1Preparation for the test run .............................................................6-1Checks after assembly ...................................................................6-1Setting and first commissioning .........................................................6-1Operation .....................................................................................................6-1Maintenance ................................................................................................7-1Inspection ....................................................................................................7-1Servicing ...............................................................................................7-1Troubleshooting ....................................................................................7-2Repair ..........................................................................................................7-3Spare parts ..................................................................................................8-1Appendix .....................................................................................................9-1Technical drawings ...............................................................................9-1Subsuppliers' documentation ..........................................................9-1
1 Technical Data
NOTE
Information on the electrical equipment is contained in the separate electrical
documentation or in the subsuppliers’s documentation.
I nformation on the intended use
The ultrasonic measuring device for material bed depth is a component of the
roller mill.
Basic data
Year of manufacture
Type
Number
Type of protection
Operating temperature
Storage temperature
Power supply …
Permissible residual ripple
Current output
Set to
Voltage output
Power consumption
Transducer frequency
Response delay
Sensing range LE
Set measuring range, start A1 A1
Set measuring range, end A2 A2
Measuring range LM
Resolution at measuring range end
Reproducibility
Linearity
Temperature drift
Weight
Design
Length
EN-16052.060-F
Equipment connecting plug
Type
Length of the connecting cable
Maximum cable length
Supply devices
Reqd. current output of the meas. transducer supply devices
2 Safety
NOTE
Be sure to comply with the general safety instructions in the supplement
Important notes on the documentation.
Use
• The measuring device is exclusively intended for measuring the material bed
depth in the roller mill.
Be sure to comply with the instructions concerning the intended use in the
section Technical data.
Any use other than the intended use is forbidden. POLYSIUS AG is not
responsible for damage resulting from any use other than the intended use.
All other use is at the owner’s own risk.
POLYSIVS AG
The intended use also includes observance of the instructions in the opera-
ting manual and the maintenance instructions.
• •
Operation
•
• Do not make any alterations to the ultrasonic measuring transducers. Any safety checks before or during operation depend on the relevant national
regulations. The plant management is responsible for the performance and
recording of such checks.
Hearing protectors have to be worn in the roller mill building.
•
EN-16052.060-F
Maintenance
• Ensure that all machines and motors whose operation might endanger
persons or equipment are switched off and safeguarded against restarting for
the entire duration of the maintenance work.
Keep the measuring devices free of oily and combustible substances and
materials. Never use gasoline or other easily inflammable materials for
cleaning the measuring device.
Switch off the power supply to the electrical components before commencing
any maintenance work.
If you carry out electrical welding on any part of the machine, never conduct
the welding current through plain or antifriction bearings, other movable
connections or measuring equipment. Always directly connect the welding
current return lead to the part being welded.
Remount all protection devices when maintenance work has been finished.
Make absolutely sure that no persons are inside the plant component before
you properly close the inspection and service covers.
• • • •
3 Components and description of functionning
NOTE
The drawings in this manual are schematic representations for better understan-ding of the descriptions.
The function of the measuring device supplied by POLYSIUS AG is to measurethe space between the roller pair unit and the grinding table of the roller mill andthus determine the material bed depth. POLYSIUS
AG
3.1 Components
The ultrasonic measuring device essentially consists of the following compo-nents:
•
•
•
• the ultrasonic measuring transducers the connecting cables the reflection plates the fixing elements
EN-16052.060-F
Items shown in the drawing
A
B
C
D
E
1
2
3
4Hydraulic cylinder Piston rod Tie rod of the roller pair unit Roller pair unit Grinding table Ultrasonic measuring transducer Reflection plate Bracket for ultrasonic measuring transducer Connecting cable with plug 1.7Fixing nut
The bracket (3) for the ultrasonic measuring transducer and the reflection
plate (2) are components of the mechanical equipment of the roller mill. 3 2
Figure 1Ultrasonic measuring device for material bed depth
EN-16052.060-F
Items shown in the drawing of the ultrasonic measuring transducer
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
2Ultrasonic measuring transducer Ultrasonic transducer Evaluation unit Instrument amplifier Program plug connector with temperature sensor LED window LED Connection socket Fixing nut Reflection plate
angle of sound beam spread
measuring range αL M
3.2 Mode of functioning of the ultrasonic measuring transducer
After application of the operating voltage, the ultrasonic transducer (1.1) sends a
defined transmission pulse (Y). For a period of time (T) the ultrasonic transducer
(1.1) is now switched to reception and the incoming echo pulse (Z) is relayed to
the evaluation unit (1.2). This filters out the usable signal and calculates the
distance to the reflection plate (2) from the sound travel time. This measured va-
lue is converted into a load independent current in the series-connected instru-
ment amplifier (1.3).
1.1 Y 1.1 T Z
1.2
1.3
Reflection plate (2) 2
The reflection plate should be at least 100 x 100 mm in size and have a maxi-
mum surface roughness of 0.2 mm. 100*100 0.2mm
Figure 2Ultrasonic measuring transducer with reflection plate
EN-16052.060-F
Influencing variables
Temperature
As this unit is equipped with temperature compensation, the influence of the
ambient temperature within the permissible operating limits is negligible.
Humidity
The difference between dry air and saturated, humid air changes the measured
value by max. 2 %, proportional to the sound velocity alteration. 2% Air pressure
Normal air pressure fluctuations cause a sound velocity alteration and thus a
change in measured value of approx. 0.6 %.
0. 6%
Air streams
Under normal ambient conditions, the influence of air streams is very slight. In thecase of higher wind speeds, however, it is possible that significant measured
value falsifications could occur. These could, for instance, also be caused by
compressed air or powerful fans.
3.3Mode of functioning of the measuring device
To determine the material bed depth LMB in the roller mill, i.e. the distance
between the roller pair units (D) and the grinding table (E), the distances L1 and
L 2 between the hydraulic cylinders (A) and the associated piston rods (B) are
measured. As a roller pair unit (D) has two hydraulic cylinders (A), the arithmeticmean value has to be computed from the two raw measured values L1 and L2,
and the initial value L0 then has to be subtracted. This initial value results from
the arithmetic mean value of the two raw measured values L01 and L02 when theroller pair unit is in contact with the grinding table and the roller carrier is
horizontal (also see Figure 4 and Figure 5). L MB D E A B L 1 L 2 A L 1 L 2 L 0 L 0 L 01 L 02 L 01 L 02 4 5
As the roller mill has two roller pair units, two calculated values LMB (1) and LMB (2)are also displayed. Because the measuring principle is identical for both rollerpair units, the following description refers to just one roller pair unit.
L MB (1) L MB (2)
Dimension factor
For the calculated values to be indicated in millimetres, they have to be multipliedby the dimension factor KD . mm K D
L MB = material bed depth LMB =
The dimension factor K D is derived from the data of the
ultrasonic measuring transducer.
Measurement curve
I [mA]
20
4
LM s [mm]
A1A2
Figure 3Measurement curve of current over travel distance L M
l
s ===
=
=measuring range current output travel distance set measuring range, start set measuring range, end A1A2
see Sect. 1
EN-16052.060-F
Initialization
To enable determination of the initial value L0, the roller pair units (D) withhorizontal roller carriers must be in contact with the grinding table (E). The
required procedure, as well as further information, are described in the machinemanual Roller mill. L 0 (D) (E)
The initial value L0 is obtained via the arithmetic mean value generation from thetwo raw measured values L01 und L02. L 0 L 01 L 02
L01 + L02
2L0 =
This initialising value L0 is the reference point for measurement of the materialbed depth and is also used for wear determination by means of measuring. Storethis constant in the master control system. L 0
The material bed depth (LMB ) is calculated as follows:
L1 + L2
2LMB =- L0
and equals zero during the initialisation.
Items shown in the drawing of the initialisation
A Hydraulic cylinder
B Piston rod
C Tie rod of the roller pair unit
D Roller pair unit
E Grinding table
1Ultrasonic measuring transducer
2 Reflection plate
L 01
L 02
L MB
L 0====raw measured value 1 when roller pair unit in contact with table 1raw measured value 2 when roller pair unit in contact with table 2material bed depth Initial value
EN-16052.060-F
Figure 4Determination of the initial value
Grinding operation
After the initialisation, you can start up the mill in accordance with the Operating manual for roller mills. Due to the building up of the bed of material, the tie rods ofthe roller pair units (C) with the mounted reflection plates (2) are drawn out of thehydraulic cylinders (A). The distances between the ultrasonic measuring transdu-cers (1) and the reflection plates (2) increase by the distance L1 - L0 or, respecti-vely, L2 - L0.
2 C A 1 2 L 1-L 0 L 2-L 0
The material bed depth is now also computed via the arithmetic mean.
LMB =(L1 - L0) + (L2 - L0)
2=(L1 + L2)
2- L0
Items shown in the drawing of the grinding operation
A Hydraulic cylinder
B Piston rod
C Tie rod of the roller pair unit
1Ultrasonic measuring transducer
2Reflection plate
L 0
L MB
L 1
L 2====Initial value material bed depth raw measured value 1 1raw measured value 2 2
EN-16052.060-F
Figure 5Determination of the material bed depth
Wear
After some time of operation, system-inherent wear of the roller pair units and the
grinding track begins. The resultant reduction in size of the grinding rollers and
the grinding track can lead to incorrect measurements of the material bed depth if
initialisation is not repeated.
Compared to the first initialisation, the operating point is lower by the amount of
the total wear LV and, therefore, the material bed depth measurement is also
incorrect by this amount.
L V
The indicated value LMB ’ has to be corrected in accordance with the equation
L MB
L MB = LMB ’ + LV
The total wear LV can only be determined by means of a new initialisation in
accordance with
L V
L V = L0 - L0’
The procedure is described under Initialisation .
Items shown in the drawing of the wear determination
A Hydraulic cylinder
B Piston rod
C Tie rod of the roller pair unit
1Ultrasonic measuring transducer
2Reflection plate
L 0
L 0’
L V
L MB ====Initial value initial value after wear amount of wear material bed depth
EN-16052.060-F
Figure 6Determination of the wear
4
4.1 Transport and assembly Transport and storage instructions
The measuring device is transported completely packed.
When they arrive at the site, all parts must be inspected for transport damage and
stored so that they are protected against rain, soiling and damage.
Store the measuring device in well aerated buildings and protect it against moi-
sture.
4.2 Assembly
General notes
The following assembly instructions do not detail the individual steps for assemb-
ling the units, but rather give an overview of the work to be performed.
Changes in the planning of the plant during the processing of the contract may
lead to deviations from these assembly instructions.
NOT E
It is a prerequisite of our warranty that final assembly and assembly inspection are un-
dertaken by an assembly specialist from POLYSIUS AG.
POLYSIVS
AG
Careful selection of tools and appliances used and of the personnel is important for the
correct execution of the assembly work.
CAUTION
If you carry out electrical welding on any part of the machine, never con-
duct the welding current through measuring equipment, in order to pre-
vent damage to these parts.
Always directly connect the welding current return lead to the part being
welded.
EN-16052.060-F
Mounting the ultrasonic measuring transducer
You can mount the ultrasonic measuring transducer in any desired position. Ho-
wever, avoid mounting locations where heavy coatings of material, jets of water
or strong air streams (compressed air) are to be expected. Furthermore, be sure
to mount the ultrasonic sensors at a minimum distance of 1 m.
1m
Mount the ultrasonic measuring transducers on the provided brackets (3) on
the hydraulic cylinders (A) (see Figure 1).
A 3 1
The tightening torque for the fixing nuts (1.7) is 15 Nm.
1.7 15Nm
NOTE
If you screw the device into a threaded hole, it is possible that lead errors
may cause over winding of the casing. Fix the ultrasonic measuring trans-
ducer in through-holes using the supplied nuts.
Connect the position measuring devices with screened cables to the higher-
level control system of the machine/plant.
/
4.3 Measurement signals to the higher-level control system
The current output is permanently set to “live zero point“ and rising ramp.
The following signals are available at the terminals:
Terminal
1
2
3
4
Table 1Designation + operating voltage+ + voltage output+ - earth + current output+ + UB Value + 0 ... 10 V- UB , Gnd + 4 ... 20 mA
Max. load Current output
Voltage output
Table 2R L ≤ 500 ΩR L ≤ 1000 Ω
EN-16052.060-F
5 Lubrication
NOTE
This measuring device requires no lubrication.
/
EN-16052.060-F
6 Preparation for the test run
NOTE
It is a prerequisite of our warranty that the first commissioning is carried out in the
presence of and according to the instructions of specialists from POLYSIUS AG.
KRUPP POLYSIUS
AG
6.1 Checks after assembly
Before starting the first commissioning, check all parts of the plant according to
the list below. Take particular care that all material remnants, tools and assembly
aids are removed.
/
Check the ultrasonic measuring transducer for secure and correct mounting.
,
Check the reflection plate for correct alignment.
Check all connections for correct polarity.
Check all cables for damage and kinks.
6.2 Setting and first commissioning
Ultrasonic measuring transducers (1) are delivered in set and sealed condition.
Subsequent attempted resetting via the programming plug connector can dama-
ge the plug connector or the installed temperature sensor. Wrongly set or faulty
ultrasonic measuring transducers must be replaced.
Before starting the grinding operation, perform an initialisation of the measuring
device. Please take note of section 3.
3
6.3 Operation
When you have successfully concluded the first commissioning, the ultrasonic
measuring device is available for measuring the material bed depth during opera-
tion. Remember to carry out a correction when necessary, in order to take ac-
count of the system-inherent wear in the roller mill. Please take note of section 3.
3
EN-16052.060-F
7
7.1
No.
1Maintenance Inspection Work to be performed Check the ultrasonic measuring transducer for
dust deposits
Check the ultrasonic measuring transducer for
secure mounting
Check the connecting cables for damage
Frequency Weekly Monthly Monthly Comments 23
7.2
No.
1Servicing Work to be performed Clean dust off the ultrasonic measuring
transducer
Frequency Weekly Comments
EN-16052.060-F
7.3
Fault Troubleshooting Cause
Wire breakage
Elimination check plug connector withcable; replace if necessary
terminal connections
not O.K.
supply voltage
not availablecheck and fasten the terminalconnections put the power supply inorder
replace the ultrasonic
sensor
initialise the measuring
device Analog signal absent,
7.4 Repair
Before performing any repair work, switch off the power supply to all electricalcomponents.
Ensure absolute cleanliness at all times during the repair work in order to preventdirt from entering sensitive parts of the machine or plant.
CAUTION
After you have completed the repair work, you must check the mea-suring device again according to the section Preparation for first
commissioning and operation.
EN-16052.060-F
8 Spare parts
Notes for enquiring about and ordering spare parts
Dear Customer,
POLYSIUS AG strive to render your enquiring about and ordering of spare partsas easy, and as a consequence, as efficient as possible. For this purpose wehave prepared a table containing all data required by our spare parts departmentto ensure optimum processing in the most speedy and trouble–free manner.
Please copy the page with the respective table and mark those parts which yourequire with a cross in the column Order or Enquiry. Code word:
Item
1
4Designation Ultrasonic measuringtransducer 5 m connecting cable with
plug 5 Order-No.:Qty . Unit AAT-Item:Order Enquiry
EN-16052.060-F
9
9.1 Appendix Technical drawings Designation
Circuit diagram Drawing no. 9.2 Subsuppliers' documentation
Ultrasonic measuring transducer
EN-16052.060-F