WEIGHING :- weighing is the process to measure the quantity of some substance in a given area by using different equipment's for different scales of weighing, after completion of the weighing process the measured quantities are given some units which are recognized globally. WEIGHMENT :- weighment is the technical term used to symbolize the process of weighing of raw material in term of S.I. unit or in some case C.G.S. according to the country or region preference. WEIGHING SYSTEM :- Weighing system is basically classified into two main categories they are:- 1. STATIC WEIGHING SYSTEM. 2. DYNAMIC WEIGHING SYSTEM.

1. PROJECT
ON
STUDY OF STOCK HOUSE WEIGHING SYSTEM
AT H-BLAST FURNACE
GUIDED BY :SUBMITTED BY:MR. DHARMENDRA KUMAR
NAME :- BISHWARUP MUKHERJEE
V.T NO. :- VT20130827
PANDEY (ASSISTANT MANAGER I.E.M.
H- BLAST FURNACE)
INSTITUTE :-BHARATH UNIVERSITY
UNDER,
DISCIPLINE :- ELECTRICAL
MR. AMAR MISRA
DURATION :- 03 WEEKS
[HEAD I.E.M (―G‖ & ―H‖)
BLAST FURNACE]
1

2. CERTIFICATE
Certified that this project ―STUDY OF STOCK HOUSE WEIGHING
SYSTEM AT H.B.F‖ is the bona fide of ―BISHWARUP
MUKHERJEE‖ V.T NO.:- VT20130827 who carried out the realistic
project under supervision.
------------------------------------------------(
signature)
MR. DHARMENDRA KUMAR
PANDEY
(ASSISTANT MANAGER I.E.M. HBLAST FURNACE)
UNDER,
MR. AMAR MISRA
(HEAD I.E.M “G” &”H”
BLAST FURNACE)
2

3. ACKNOWLEDGEMENT
At this pleasing moment of having successfully complete the project I
wish to convey my sincere thanks and gratitude to the management of
TATA STEEL and S.N.T.I. who provide all facilities to me. I would like
to express my sincere thanks to the head of I.E.M. G&H BLAST
FURNACE , MR. AMAR MISRA for forwarding me to do this project
and offering adequate duration in completing the project. With deep
sense of gratitude I extend our earnest and sincere thanks to my project
guide MR. DHARMENDRA KUMAR PANDEY (department of
I.E.M ―H-BLAST FURNACE‖) for his guidance and encouragement
during the project.
3

4. INDEX
SL.NO.
TOPIC
PAGE NO.
1.
INTRODUCTION
5
2.
WEIGHING SYSTEM & TYPES
5-6
3.
STATIC WEIGHING
6-7
(I)WEIGH HOPPER
7
(1) HOPPER
8-11
(2) LOAD CELL
12-19
(II)PLATFORM WEIGHING
19
WEIGH BRIDGE
20-21
DYNAMIC WEIGHING
22
BELT WEIGHER
23-34
5.
CONCLUSION
35
6.
REFERENCES
36
4.
4

5. INTRODUCTION
WEIGHING :-
weighing is the process to measure the quantity of some substance in a
given area by using different equipments for different scales of
weighing, after completion of the weighing process the measured
quantities are given some units which are recognized globally.
WEIGHMENT :-
weighment is the technical term used to symbolize the process of
weighing of raw material in term of S.I. unit or in some case C.G.S.
according to the country or region preference.
WEIGHING SYSTEM :-
Weighing system is basically classified into two main categories they
are:1. STATIC WEIGHING SYSTEM.
2. DYNAMIC WEIGHING SYSTEM.
5

6. STATIC WEIGHING
As the name suggests, the goods or products are stationary when they
are being weighed on these scales and usually there is more than
sufficient time for the measurement process to stabilize before readings
are taken.
There are three types of static weighing :-
A)Mech. Weighing B) Weigh hopper
C) Platform weighing
(weigh bridge)
“AT HBF ONLY WEIGH HOPPER AND WEIGH
BRIDGE ARE USED”
6

7. “At H-blast furnace we use
weigh hopper for raw material
weighing and weigh bridge for Hot metal weighing purpose.”
WEIGH HOPPERS
A weigh hopper is an item of equipment that is required when there is a
need to collect and accurately weigh a product prior to the next process.
We primarily manufacture weigh hoppers for measuring shredded
materials, but also with the use of our in house design facility for many
other applications. All weigh hoppers can be fed by gravity, belt
conveyors, screw, vibratory feeders or air conveyors.
7

8. CONFIGRATION OF WEIGH HOPPER(FIELD DATA ) :MATERIAL
WEIGH HOPPER
NAME
CAPACITY
NO. OF WEIGH
HOPPER
CENTER
COKE
CCWH1
(tonnes)
13.75t
CCWH2
13.75t
SURFACE
COKE
CWH1
13.75t
CWH2
13.75t
CWH3
13.75t
CWH4
SWH1
13.75t
76.5t
SWH2
76.5t
SWH3
76.5t
SWH4
OWH1
76.5t
60t
OWH2
60t
OWH3
60t
4
OWH4
NCWH
SFWH
60t
3.75t
15.75t
1
1
AWH1
9t
AWH2
9t
3
AWH3
DRIWH
9t
9t
1
SINTER
IRON ORE
NUT COKE
SINTER
FINES
ADDITIVE
DRI
2
4
4
8

9. CAPACITY OF WEIGH HOPPER :At HBF the weigh hopper are in the range of :(5-90t)-“which are held by 3 LOAD CELL each”.
“ABOVE SHOWN IS THE SIMILER STRUCTURE OF THE
WEIGH HOPPER WHICH ARE USED IN THE H-BLAST
FURNACE”
PARTS OF WEIGH HOPPER:Weigh hopper are made up of two main parts:1.Hopper.
2.Load cells.
9

10. HOPPER:Hoppers are the structures which are generally conical at bottom, these
structure carry different raw material for the purpose of manufacturing.
These structures stores raw material which are balanced by load cells at
the bottom. The configuration of the load cell my vary from industries to
industries, at HBF three load cells are used for the each hopper,
separated by 120 degree apart.
“ABOVE SHOWN IS THE BASIC STRUCTURE OF THE
HOPPER.”
10

11. RAW MATERIAL MOVING PROCESS IN THE WEIGH
HOPPER:-
“Above shown is the block diagram of raw material
movement in the stock house of h-blast furnace” .
11

12. LOAD CELLS :-
A Load cell is a transducer that is used to convert a force/weight into
an electrical signal. This conversion is indirect and happens in two
stages. Through a mechanical arrangement, the force being sensed
deforms a strain gauge. The strain gauge measures the deformation
(strain) as an electrical signal, because the strain changes the effective
electrical resistance of the wire.
A load cell usually consists of four strain gauges in a Wheatstone
bridge configuration. Load cells of one strain gauge (Quarter Bridge) or
two strain gauges (half bridge) are also available. The electrical signal
output is typically in the order of a few mill volts and requires
amplification by an instrumentation amplifier before it can be used. The
output of the transducer can be scaled to calculate the force applied to
the transducer.
12

13. TYPES OF LOAD CELL:-
1. Stainless steel sheer beam load
cell.
Capacity - 500kg---5t
Type – N/C3/C3MR.
2. Bending beam load cell.
Capacity - 5kg---500kg
Type – N/C3/C3MR/C3MR+.
3. Precision compression load
cell.
Capacity – 100t---300t
Type – L/LA/N/NE.
13

14. 4. Compact compression load cell.
Capacity – 30KG---10T
500KG---5T.
Type – D1/LT.
5. Weigh bridge load cell.
Capacity – 20T---75T.
Type – C3/C4/C5/C6.
6. Compression s-type load cell.
Capacity - 100KG---5T.
Type – D1/C3/C6.
7. Tension s-type load cell.
Capacity - 100KG---3T
Type – D1/C3/C6.
14

15. ―AT H-BLAST FURNACE ONLY PRECISION
COMPRESSION LOAD CELLS ARE USED FOR WEIGH
HOPPER‖
DETAIL ABOUT COMPRESSION LOAD CELL. :SPECIFICATION (of PCLC at H-BLAST
FURNACE):-
1. No. of load cells used in one weigh hopper = 3.
2. Orientation =each load cell is separated by one
another by 120 degree angle.
15

16. 3. Capacity of load cells = 100t---300t(as per requirement)
4. Sensitivity =1mv/v---2mv/v.
5. Supply voltage = 12 volts (dc).
8. Cable identification:-
THE COMPRESSION LOAD CELL BASICALLY HAS,
6-COLOURED CABLES:1.RED/BROWN — SUPPLY + (V+).
2.BLUE – SUPPLY – (V-).
3.BLACK – SNESE + (S+).
4.WHITE – SENSE – (S-).
IN SOME CASES (BLACK AND
WHITE) CABLE MAY NOT BE
THERE.
5.GREEN – OUTPUT + (M+).
6.GREY/YELLOW – OUTPUT – (M-).
16

17. INTERNAL STRUCTURE OF A COMPRESSION LOAD
CELL :-
ABOVE SHOWN IS THE INTERNAL STRUCTURE OF A
COMPRESSION TYPE LOAD CELL.
OPERATION:The whole system works on the priciple of the wheat stone
bridge,as shown below.
17

18. When pressure is applied on the load cells then in that case the
horizontal as well as the vertical strain gauge which are mounted
on a chip sticked to the high modulous metal inside the
hemispherical sealed chamber compresses and expands resp. due
to which the resistance of the strain gauge changes.because, we
know that,
Were,
R = Resistance.
L = Length
A = Area.
when the load is put on the load cell the horizontal strain gauge
compresses and due to which the length of the strain gauge
decreases and the area increase. Hence, the resistance of the
strain gauge also changes accordingly.
And in case of vertical strain gauge the length increases and the
area decreases. As,a result of that the resistance also changes.
Inside the sealed chamber there exist a vacuum and pure
nitrogen(N) is inserted inside the chamber. this process increases
the life of the load cells. On load cell can withstand the load of
the weigh hopper for more than 100 years.
18

19. CONNECTION OF THE LOAD CELL :-
“SHOWN ABOVE IS THE CONNECTION DIAGRAM OF
A LOAD CELL”.
PLATFORM WEIGHING :Platform weighing is a techniqe of weighing by using a plane surface or
even surface, this weighing method is applied basically for weighing
much larger materials which are not in a regular shape or which cannot
be weighed by other piece of weighing process present in the vicinity.
―AT H-BLAST FURNACE IN THE NAME OF
PLATFORM WEIGHING WEIGH BRIDGE IS USED
FOR THIS PURPOSE.‖
19

20. WEIGH BRIDGE:A weighbridge is a large set of scales, usually mounted permanently on a
concrete foundation, that is used to weigh entire rail or road vehicles and
their contents. By weighing the vehicle both empty and when loaded, the
load carried by the vehicle can be calculated.
The key component that uses a weighbridge in order to make the weigh
measurement is load cells.
Weigh bridge can be surface mounted with a ramp leading up a short
distance and the weighing equipment underneath or they can be pit
mounted with the weighing equipment and platform in a pit so that the
weighing surface is level with the road. They are typically built from
steel or concrete and by nature are extremely robust.
In earlier versions the bridge is installed over a rectangular pit that
contains levers that ultimately connect to a balance mechanism. The
most complex portion of this type is the arrangement of levers
underneath the weighbridge since the response of the scale must be
independent of the distribution of the load. Modern devices use
multiple load cells that connect to an electronic equipment to totalize the
sensor inputs. In either type of semi-permanent scale the weight readings
are typically recorded in a nearby hoser hut or office.
Many weighbridges are now linked to a personal computer which
runs weigh bridge software capable of printing tickets and providing
reporting features.
20

21. WEIGH BRIDGE CONFIGRATION FOR HBLAST FURNACE:-
1.quantity :- one
2.total capacity :- 800t.
3.No. of load cells in each weigh bridge :- 4.
4.make :- sartorius
6.sensitivity :- 1mv/v.
21

22. DYNAMIC WEIGHING
Dynamic weighing covers a wide range of applications either where the
product, goods or vehicle are weighed while moving, or the scale itself
is moving as with onboard ship scales. Most dynamic applications are
considered to be automatic weighing. Filling machines are a large sector
of dynamic weighing and therefore are dealt with separately .
Belt conveyors are the fastest mode of material transportation in mining
and process industries where bulk material transportation is the
important criterion. It is required to measure material transported over
these conveyors, In order to achieve consistent quality in the process and
accountability. Sartorius Belt weigher are designed to achieve this by
delivering consistent accuracy and reliability. Belt weigher is basically a
load measurement system installed in a conveyor belt. Which is
designed to indicate and record the flow rate of the material conveyed
from one location to another location. It will also record the total weight
conveyed per unit time. High precisions Sartorius Load Cells are used
for measuring the load. Reliable Speed measuring device is used to
measure the belt speed. Using these two Parameters (Load & Speed) the
material flow rate can be expressed in terms of tonnes/hour. This flow
rate output is integrated with respect to time for giving the continuous
totalized value of the material conveyed.
22

23. “AT HBF WE USE BELT WEIGHER UNDER THE CATEGORY
OF DYNAMIC WEIGHING”
BELT WEIGHER:Belt conveyors are the fastest mode of
material transportation in mining and
process industries where bulk material
transportation
is
the
important
criterion. It is required to measure
material transported over these
conveyors, In order to achieve
consistent quality in the process and
accountability. Sartorius Belt weigher
are designed to achieve this by delivering consistent accuracy and
reliability. Belt weigher is basically a load measurement system installed
in a conveyor belt. Which is designed to indicate and record the flow
rate of the material conveyed from one location to another location. It
will also record the total weight conveyed per unit time. High precisions
Sartorius Load Cells are used for measuring the load. Reliable Speed
measuring device is used to measure the belt speed. Using these two
Parameters (Load & Speed) the material flow rate can be expressed in
terms of tonnes/hour. This flow rate output is integrated with respect to
time for giving the continuous totalized value of the material conveyed
Main features of Sartorius Belt Weighers are :1. Simple installation and easy maintenance.
2. Trouble free operation under severe environmental
conditions.
3. Practically no effect of belt tension on weighing.
4. Remote data transmission.
5. High reliability and accuracy.
6. Easy integration with supervisory systems.
23

24. Belt weigher consists of the following components:1. Load cells with Belt weighing frame to measure the load.
2. Weigh Idlers.
3. Speed measuring device (encoder) with mounting.
arrangement to measure the speed.
4. Encoder mounting arrangement.
5. Controller to process load and speed data and display the
Flow Rate/totaliser.
The Formula to Calculate the Flow rate is :-
Q = P x V x 3600
Were,
Q= Flow Rate in TPH
P= Load in kg/m
V= Speed in m/s
24

25. CONVEYOR SPECIFICATION :Conveyer Capacity : 50 TPH
Belt Width in mm : 800
Bulk density T/m3 : 2.1
Total load on Weigh Frame
(Span 0.8Mtr.x Belt load)
: 8.55
Speed in M/s : 1.3
Conveyer belt weight : ~7.0 kg/m
Load cell Type : MP 77/12 C3
Tacho Type : Digital
Make :
Pepperl
Calibration Rod : 5.5 Kg
Accuracy : +/- 0.5% of FSD
25

26. BASIC BLOCKS OF BELT WEIGHER
26

27. THE BELT WEIGHER CONSISTS OF THE
FOLLOWINGS :1.BELT WEIGHER MECHANICALS:The Belt weigher platform is a compact, rugged fabricated structural
frame. These frames support the weighing idler and are isolated from
conveyer stringer. The weighing idler /pre & post idlers are machined to
limit the radial run out. The encoder-mounting idler is supported on a
pivot frame with pillow blocks. The encoder is coupled to the wheel
shaft. This assembly is mounted on or top of the return belt on the
conveyor stringer.
Weighing idler
Calibration Rod
Roller rod is used for calibration purpose. The weight of the rod is
calculated based on therated belt load.
“AT H-BLAST FURNACE WE USE 5.5KG LOAD FOR
THE CALIBRATION PROCESS”
27

28. CALIBRATION PROCEDURE OF A BELT
WEIGHER :-
1. After the proper installation of weigh frame, the encoder and the
controller, calibrate the weighing system.
2. Internal weigh point should be enabled for doing the calibration.
3. Refer to the Pro-X4 instruction manual for programming and
calibration.
4. The Belt Weighing System is calibrated at site with a calibration rod
of known weight.The weight is punched on the calibration rod.
The process of calibration involves two steps :a. Static Zero Calibration
b. Static Span calibration
c. Rod calibration
28

29. a. Static Zero Calibration
This is carried out when there is no load on the belt at ―Conveyor off‖
condition. Select ‗Weighing Point‘ from ‗Config‘ Menu. Controller
Displays ―Calibration‖ menu. For performing a new calibration select
―New‖ from the list and perform ‗Zero Calibration‘ when there is no
load on the conveyor. Pro-X4 operations manual can be referred for
performing the Calibration.
b. Static Span Calibration
Span calibration should be done, after performing ‗Zero Calibration‘.
Span calibration could be carried out using Calibration rod. All of these
are explained in the following sections.
c. Rod calibration
The weight of the calibration rod is punched on the rod however the
same can be verified using a weighing scale. Place the Calibration rod
on the conveyor and set the Span Value according to the weight of
Calibration rod. After the Span Calibration Press ―Exit‖ button,
Controller provides an option for saving the Calibration.
Now the system is ready for use.
29

30. 2. LOAD CELL :Load cells are heart of the system. They are strain gauge based
transducers, which converts mechanical force (strain) into electrical
signal (mV) when given an excitation voltage.Strain gauges are arranged
in a wheat stone bridge network by bonding to the especially
designed/machined steel membrane. This is housed in an SS enclosure
with inert gas filled and comes with a protection of IP68.When load is
applied the resistivity in strain gauges changes proportional to applied
load. The change in resistance is converted to electrical signal by giving
an excitation voltage. Loadcell will have an integral 4 core cable of
standard length. Two cores are connected for supply voltage to the load
cell & other two for the measuring voltage from the load cell.
“ABOVE SHOWN IS THE LOAD CELL STRUCTURE
USED IN THE H-BLAST FURNACE ALONG WITH THE
ROLLER WHICH CALCULATES (TURN/HOUR).”
30

31. LOAD CELL SPECIFICATION:Make : Sartorius
Type Of Load cell : Bending beam type
Type No. : MP77/12C3
Housing Construction : Full stain less steel construction, hermetically
sealed (IP 67), filled with inert gas
3. ENCODER :The encoder coupled to idler senses the speed of the conveyor. The
encoder is a digital pulse encoder type whose output frequency is
proportional to the speed of the belt. The encoder is excited with 5V DC
supply from the controller. The pulse output is fed to the controller.
4. WEIGHING CONTROLLER :The X4 controller is microprocessor based multitasking operator system.
This controller is equipped with a high precision weighing point and
analog to digital Converter. The controller has a VFD display and a
multi foil keypad at front side and the process interface at rear side. The
controller can be loaded with Belt Weigher application programs.
31

32. 32

33. 5. ENCODER INTERFACE MODULE :Encoder interface is a module for dividing the frequency of the encoder
output to required frequency .The input frequency is 0 to 10 kHz and
output frequency is 0 to 55 HZ. The divider setting can be selected with
the dipswitch selection depending on the requirement. Thee are also
annunciation for power On, pulse out, Error and pulse IN and pulse
OUT. If the frequency exceeds 55 Hz there is an error output.
6. PANEL :The floor mounted panel, with dimension (2100 X 800 X 600) MM to
houses 6 set of following X4 Process Controller (PR5510/00) with
option cards and Encoder Interface module (ST 5010/00), Also houses
the switchgears like MCB, Relays, Terminal blocks, Annunciation
Lamps, 24V DC power supply Unit & Service socket. The various
input/outputs configured in the panel are as follows.
Annunciations: 24V DC Cluster LED lamps for BELT ON, FAULT
& TOT. PULSE.
ANALOG INPUT/OUTPUTS
Load cell Input: mV input from load cell corresponding to load on
load cell.
Analog Output:
1. 4-20mA corresponding to rate for customer requirement.
2. 4-20mA corresponding to Speed for customer requirement.
33

34. DIGITAL INPUT/OUTPUT
Inputs:
Speed input : encoder (field)
Outputs:
Belt ON : This output is given by the controller when the controller
receives the speed
Input signal from field.
Totaliser Pulse : This is the totaliser pulse output. This interval can be
set from the
controller i.e. pulse for every 1,2,5 or 10 increment.
Cumulative fault: This is output from the controller for ADC fault,
belt overload,
belt under load.
7. LOAD CELL EXTENSION CABLE :It is very important to note following factors: As the length of the cable
increases, the resistance increases. This leads to drop in the voltage. As
the electronics is temperature dependent, change in temperature will lead
to change in the voltage being supplied to the load cell. Both these above
factors will lead to error in readings. As mentioned earlier, a special
cable is connected between Cable junction Box and the indicator. It has
six cores. Usually any loadcell will have four cores. The two extra cores
in this cable are used to sense the voltage reaching the junction box. The
indicator has a unique feature of compensating for the change / drops in
the voltage such that the reading remains stable. Hence eliminating the
error due to above-mentioned reasons.
34

35. CONCLUSION
Weighing system is an important factor in the accurate production of
quality steel to given recipes. Hopper weighing provides total weight
indication with pressure compensation and flow rate indication derived
from weight data change over time. The load cells provide data for total
hot metal weight, poured weight and residual weight in torpedo cars.
This makes pouring operations more accurate and better controlled.
Hence,I conclude that this project gives a realistic and technical
approach to the stock house weighing system at and tells us about the
use of static as well as dynamic schemes at H-Blast Furnace.
35

36. REFERENCES
 http://www.wikipedia.org/ WIKIPEDIA.
 http://google.co.in GOOGLE WEB SEARCH.
 http://google.co.in/images GOOGLE IMAGE SEARCH.
 http://www.enggforyou.com
WEIGHING SYSTEM
 http://electroschematics.com/ ELECCTRON SCHEMATICS.
 http://weighingsystem.co.uk/ DIFFERENT TYPES OF
WEIGHING PROCESS
36