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A
Seminar Report on
PRACTICAL TRAINING TAKEN AT
RAMSARUP INDUSTRIES LTD., KOLKATA
submitted in partial fulfillment of
requirements for the degree
of
B.TECH.
MECHANICAL ENGINEERING
Submitted by
Imran Younus(09EGJME025)
Submitted to
Mr. Sunil SharmaAssistant Professor
DEPARTMENT OF MECHANICAL ENGINEERINGGlobal Institute Of Technology
Sitapura, Jaipur-3020222012-13
ii
Global Institute Of Technology
DEPARTMENT OF MECHANICAL ENGINEERING
JAIPUR (RAJASTHAN)-302022
CERTIFICATE
This is to certify that this seminar report on Practical Training taken at “Ramsarup
Nirmaan Wires” of “Ramsarup Industries Ltd., Kolkata” is submitted by IMRAN
YOUNUS and Univ. Roll. No. 09EGJME025 to the Department of Mechanical
Engineering, Global Institute of Technology, Jaipur for the award of the degree in
B.Tech. Mechanical Engineering is a bonafide record of work carried out by him.
The contents of this Seminar Report in full or in parts have not been submitted to
any other Institute or University for the award of any degree or diploma.
Mr. Sunil Sharma Mrs. Bhavana Mathur
Seminar Coordinator Head of Department
iii
Acknowledgement
I find myself very fortunate to have undergone my Industrial Training from
RAMSARUP INDUSTRIES LTD. at Ramsarup Nirmaan Wires, Durgapur.
The persons of my department have extended their warm and helping hand. I am
very fortunate to get a chance to know & understand the processes undergone in the
Repairing Department.
It was a golden opportunity for me to get an exposure in such a renowned company,
where discipline and quality are main motto.
I am also very thankful to the shop supervisors and workers for being kind and give
helping hand in gaining the knowledge.
I am also thankful to the management board of my college who has included this
type of training to impart practical knowledge by exposing ourselves to the industry.
I hope this training, which is the fruit of long dedicated hours of efforts & consistent
dedication, will also be appreciated. No work can be perfect, without ample
guidance. I would like to express my deep gratitude & heartiest thank to my Head of
the Department of Mechanical Engineering Mrs. Bhavana Mathur and the Training
Seminar Coordinators Mr. Sunil Sharma & Mr. Saket Sharma who infused me
with the spirit to work upon challenging field, which has its inception in such a time
when there is a dire need for new orientation.
Imran Younus
09EGJME025
iv
CONTENTS
Chapter No.
TitlePage No.
1. INTRODUCTION 01
1.1. Profile 01
1.1.1.Ramsarup Industrial Corporation
03
1.1.2.Ramsarup Nirmaan Wires
04
1.1.3.Ramsarup Lohh Udyog
05
1.1.4.Ramsarup Infrastructure
05
1.1.5.Ramsarup Utpadak
06
1.1.6.Ramsarup Vidyut
07
2. RAMSARUP NIRMAAN WIRES 08
2.1. Wire Rod 09
2.2. Surface Treatment 09
2.3. Wire Drawing 09
2.4. Stranding 09
2.4.1. Advantages of Stranded Wires 09
2.4.2. Disadvantages of Stranded Wires 10
3. SURFACE TREATMENT 11
3.1. Process 12
3.2. Disadvantages 13
3.3. Waste Products 13
v
3.4. Alternatives 13
3.5. Pickling of Steels 14
3.6. Phosphoric Acid 14
3.6.1. Rust Removal 14
4. WIRE DRAWING 16
4.1. Process 16
4.2. Lubrication 19
4.3. Mechanical Properties 19
4.4. Drawing Dies 20
5. STRANDING 21
5.1. Number of Strands 21
6. PACKING 23
6.1. Seaworthy Packing Procedure 23
6.1.1. Vendor’s Obligation and Responsibilities 24
6.1.2. Steel Structure and Plates 25
CONCLUSION 26
REFERENCES 27
vi
LIST OF FIGURES
Figure No. Title Page No.
1.1 Customer Base 02
1.2 Ramsarup Industrial Corporation 03
1.3 Ramsarup Nirmaan Wires 04
1.4 Ramsarup Lohh Udyog 05
1.5 Ramsarup Infrastructure 06
1.6 Ramsarup Utpadak 06
1.7 Ramsarup Vidyut 07
2.1 Manufacturing Process 08
3.1 Pickling Process 11
4.1 Wire Drawing Concept 16
4.2 High Speed Wire Drawing Machine 18
4.3 Carbide Wire Drawing Die 20
6.1 Seaworthy Packing 23
vii
CHAPTER 1
INTRODUCTION
RAMSARUP GROUP was founded in 1966 and has grown substantially in last of the
decades. It is one of the largest manufacturer of steel wires and a leading player in
TMT manufacturing in Eastern India. The infrastructure division is involved in power
transmission and distribution, bridge-building and laying of sewerage and water
pipelines. It is one of the fastest growing groups catering to the power and
infrastructure sectors in India and they aim to consolidate the position by initiating
steps towards organic and inorganic growth.
In keeping with the goal to be one of the most integrated players in the steel sector,
they have put up an integrated steel plant at Kharagpur to act as a feeder for the
existing wire and TMT units.
The Group turnover was over Rs. 2000 Crores (US $ 385 Millions) in 2008-09 with a
net worth of over Rs. 450 Crores (US $ 82 Millions).
They provide themselves on the fact that brand Ramsarup is highly regarded for its
consistent quality.
At Ramsarup, they believe that sustainability is key; Cornerstone of the dream is to
emerge as one of the most profitably and environmentally sustainable enterprises with
complete integration from iron ore to transmission lines.
1.1 Profile:
Ramsarup Industries Limited was incorporated in 1979.
It is a profit making and dividend paying company.
The company is listed at National Stock Exchange, Bombay Stock Exchange
and Calcutta Stock Exchange.
1
The company is engaged in manufacturing of wires, TMT bars and steel.
Also engaged in infrastructure development of India.
The head office is in Kolkata Operates through its only office at Kolkata and
the plants are at Kalyani, Durgapur, Shyamnagar & Kharagpur. The products
are sold from Kutch to Kamrup and Kashmir to Kanyakumari.
The company has six units :-
a) Ramsarup Industrial Corporation
b) Ramsarup Nirmaan Wires
c) Ramsarup Lohh Udyog
d) Ramsarup Infrastructure
e) Ramsarup Utpadak
f) Ramsarup Vidyut
Broad customer base both in terms of segment & geographical spread.
Power is the major thrust area, with almost 40% of the top line coming from
the power sector.
Fig. 1.1 Customer Base
2
1.1.1 Ramsarup Industrial Corporation:
Commenced its manufacturing activities in 1966.
Installed capacity of steel wires - 1, 97,000 MTs (coated and uncoated).
An ISO 9001: 2000 Unit.
One of the largest manufacturer of steel wires in India. Vast range of G I
Wires from 4 guage to 24 guage (26 different sizes).
Fig. 1.2 Ramsarup Industrial Corporation
Un-interrupted production since inception.
Registered with PGCIL, APDRP Projects, and Electricity Boards etc.
Building new capacities to tap the opportunities in the power transmission
and distribution sector in India.
Selling material under its brand "RAMSARUP".
Exporting its products to several countries.
3
1.1.2 Ramsarup Nirmaan Wires:
Started in 2008.
Manufacturing Low Relaxation Pre-stressed Concrete (LRPC) Strand,
Single Line LRPC Wires & other speciality wires.
First in India to manufacture Single Line LRPC Wires.
State of the art unit with complete automated machines imported from GCR,
Italy.
Installed Capacity: 54,000 MTPA (1st Phase) and 30,000 MTPA (2nd Phase).
47,000 MTPA 3rd Phase under implementation.
The LRPC wires manufactured by Ramsarup confirm to global standards and
are utilized in construction of pre-stressed girders for Roads River & railway
bridges and flyovers, pre-stressed atomic rector domes, slabs, silos hangers,
aqueducts, high-rise buildings and railway sleepers.
Fig. 1.3 Ramsarup Nirmaan Wires
3rd phase comprises of plating line to produce hose wire, staple wire,
electroplated wire, rope wire, annealed wire etc.
An ISO 9001:2000 company.
Working towards ISO 14000:2004 & 18001:2007.
Products made as per IS 14268/1995, JIS 3536, JIS 3536, ASTM A 416-98a,
BIS 589 and also as per clients specification.
4
Selling material under its brand "RAMSARUP".
Exporting its products to several countries around the globe.
1.1.3 Ramsarup Lohh Udyog:
Formed as a separate company in the year 2004.
Was merged with Ramsarup Industries Limited in the year 2008.
The unit has been put up to complete the integration mission of Ramsarup i.e.
from iron ore mines to transmission lines.
Fig. 1.4 Ramsarup Lohh Udyog
Will feed the wire units and TMT unit of Ramsarup Industries Limited.
Total land area – 325 acres.
1.1.4 Ramsarup Infrastructure:
Since large part of products used in Transmission & Distribution work like
Cables, Conductors, Poles, Earth Wires, Stay Wires requires steel wires to be
used directly/ indirectly, we decided to enter into this business. Further, It is
already registered with most of the electricity boards of India it was rationale
decision to extend The relationship. It also helped us in increasing The
customer base for wires and also in reducing The cost of purchases of
Conductors & Cables due to The strong presence in wire business
5
Fig. 1.5 Ramsarup Infrastructure
The strong civil & design/ drawing team encouraged as to get into other civil
related infra projects like bridges, sewerage and water pipelines
Joint venture partners also provided us with required expertise
1.1.5 Ramsarup Utpadak:
Ramsarup Industries Limited took over the Steel Division of Nicco
Corporation Ltd in August 2002. The above unit is engaged in manufacturing
of TMT Bars, Wire Rods and Steel Wires.
Installed capacity of TMT Bars (Re-inforcement & Debars) - 167000 MTs &
Steel Wires - 36000 Mts.
An ISO 9001:2000 unit.
Fig. 1.6 Ramsarup Utpadak
Only producer in India to provide complete range of 8mm to 40mm Bars
using thermal Technology.
6
Supplier to large projects and companies and registered with Contractor of
NHPC, NTPC, CPWD, Nuclear Power Corporation etc.
Selling material under its brand "RAMSARUP".
1.1.6 Ramsarup Vidyut:
The company has installed 3 nos of Wind Turbine Generators of capacity 1.25
mw each at Dist Dhule in Maharashtra, India.
Fig. 1.7 Ramsarup Vidyut
7
CHAPTER 2
RAMSARUP NIRMAAN WIRES
It is one of the six units of Ramsarup Industries Ltd. It is engaged in Manufacturing
Low Relaxation Pre-stressed Concrete (LRPC) strand, Single Line LRPC Wires &
other speciality wires. It is first in India to manufacture Single Line LRPC Wires. It
is situated in Durgapur, West Bengal (INDIA).
The company manufacture LRPC Strands/Wires by using the manufacturing process
as given below:
Fig. 2.1
Manufacturing Process
2.1 Wire Rod:
8
Wire rod is a rolled alloy or nonalloy steel product, produced from a semi (e.g.
bloom) and having a round, rectangular or other cross-section. Particularly fine
cross-sections may be achieved by subsequent cold forming (drawing). Wire rod is
wound into coils and transported in this form.
2.2 Surface Treatment:
Surface treatment is a broad range of industrial processes that alter the surface of a
manufactured item to achieve a certain property. It is a metal surface treatment used
to remove impurities, such as stains, inorganic contaminant
rust or scale from ferrous metals, copper and aluminium alloys. A solution called
pickle liquor, which contains strong acids, is used to remove the surface impurities. It
is commonly used to de-scale or clean steel in various steelmaking processes.
2.3 Wire Drawing:
Wire drawing is a metalworking process used to reduce the cross-section of a wire by
pulling the wire through a single, or series of, drawing die(s). There are many
applications for wire drawing, including electrical wiring, cables, tension-loaded
structural components, springs, paper clips, spokes for wheels, and stringed musical
instruments.
2.4 Stranding:
Stranded wire is helpful, especially in larger wire sizes to enable more flexibility in
routing of the wire and offers more durability for applications where vibration and
occasional movement of the wire could cause breakage of a stiffer solid wire.
2.4.1 Advantages of Stranded Wire:
1. More flexible for routing
2. More durable for vibration and infrequent movement.
2.4.2 Disadvantages of Stranded Wire:
9
1. Larger size.
2. More costly especially as stranding increases as more processing is required
to manufacture it.
10
CHAPTER 3
SURFACE TREATMENT
Surface treatment is a broad range of industrial processes that alter the surface of a
manufactured item to achieve a certain property. Treatment processes may be
employed to: improve appearance, adhesion or weldability, solderability, corrosion
resistance, tarnish resistance, chemical resistance, wear resistance, hardness, modify
electrical conductivity, remove burrs and other surface flaws, and control the surface
friction. In limited cases some of these techniques can be used to restore original
dimensions to salvage or repair an item.
Fig. 3.1 Pickling Process
11
Pickling is a metal surface treatment used to remove impurities, such as stains,
inorganic contaimina rust or scale from ferrous metals, copper and aluminum alloys.
A solution called pickle liquor, which contains strong acids, is used to remove the
surface impurities. It is commonly used to descale or clean steel in
various steelmaking processes.
3.1 Process:
Many hot working processes and other processes that occur at high temperatures
leave a discoloring oxide layer or scale on the surface. In order to remove the scale
the workpiece is dipped into a vat of pickle liquor.
The primary acid used is hydrochloric acid, although sulphuric acid was previously
more common. Hydrochloric acid is more expensive than sulphuric acid, but it
pickles much faster while minimizing base metal loss. The speed is a requirement for
integration in automatic steel mills that run production at high speed; speeds as high
as 800 ft/min (≈243 metres/min) have been reported.
Carbon steels, with an alloy content less than or equal to 6%, are often pickled in
hydrochloric or sulphuric acid. Steels with an alloy content greater than 6% must be
pickled in two steps and other acids are used, such
as phosphoric, nitric and hydrofluoric acid. Rust- and acid-resistant chromium-nickel
steels are pickled in a bath of hydrochloric and nitric acid. Most copper alloys are
pickled in dilute sulphuric acid, but brass is pickled in concentrated sulphuric and
nitric acid mixed with sodium chloride and soot.
In jewellery making, pickling is used to remove the oxidation layer from copper
surfaces, which occurs after heating. A diluted sulphuric acid pickling bath is used.[3]
Sheet steel that undergoes acid pickling will oxidize (rust) when exposed to
atmospheric conditions of moderately high humidity. For this reason, a thin film of
oil or similar waterproof coating is applied to create a barrier to moisture in the air.
This oil film must later be removed for many fabrication, plating or painting
processes.
12
3.2 Disadvantages:
Acid cleaning has limitations in that it is difficult to handle because of its
corrosiveness, and it is not applicable to all steels. Hydrogen embrittlement becomes
a problem for some alloys and high-carbon steels. The hydrogen from the acid reacts
with the surface and makes it brittle and causes cracks. Because of its high reactance
to treatable steels, acid concentrations and solution temperatures must be kept under
control to assure desired pickling rates.
3.3 Waste products:
Pickling sludge is the waste product from pickling, and includes acidic rinse waters,
metallic salts and waste acid. Spent pickle liquor is considered a hazardous waste by
the EPA. Pickle sludge from steel processes is usually neutralized with lime and
disposed of in a landfill. After neutralization the EPA no longer deems it a hazardous
waste. The lime neutralization process raises the pH of the spent acid and
makes heavy metals in the sludge less likely to leach into the environment. Since the
1960s, hydrochloric pickling sludge is often treated in a hydrochloric acid
regeneration system, which recovers some of the hydrochloric acid and ferric oxide.
The rest must still be neutralized and disposed of in landfills. The by-products of
nitric acid pickling are marketable to other industries, such as fertilizer processors.
3.4 Alternatives:
Smooth clean surface (SCS) and eco pickled surface (EPS) are more recent
alternatives. In the SCS process, surface oxidation is removed using an engineered
abrasive and the process leaves the surface resistant to subsequent oxidation without
the need for oil film or other protective coating. EPS is a more direct replacement for
acid pickling. Acid pickling relies on chemical reactions while EPS uses mechanical
means. The EPS process is considered "environmentally friendly" compared with
acid pickling and it imparts to carbon steel a high degree of rust resistance,
eliminating the need to apply the oil coating that serves as a barrier to oxidation for
acid-pickled carbon steel.
13
3.5 Pickling of steel:
One of the most important applications of hydrochloric acid is in the pickling of
steel, to remove rust or iron oxide scale from iron or steel before subsequent
processing, such as extrusion, rolling, galvanizing, and other techniques. Technical
quality HCl at typically 18% concentration is the most commonly used pickling
agent for the pickling of carbon steel grades.
Fe2O3 + Fe + 6 HCl → 3 FeCl2 + 3 H2O
The spent acid has long been re-used as iron (II) chloride (also known as ferrous
chloride) solutions, but high heavy-metal levels in the pickling liquor have decreased
this practice.
The steel pickling industry has developed hydrochloric acid regeneration processes,
such as the spray roaster or the fluidized bed HCl regeneration process, which allow
the recovery of HCl from spent pickling liquor. The most common regeneration
process is the pyrohydrolysis process, applying the following formula:
4 FeCl2 + 4 H2O + O2 → 8 HCl+ 2 Fe2O3
By recuperation of the spent acid, a closed acid loop is established. The iron (III)
oxide by-product of the regeneration process is valuable, used in a variety of
secondary industries.
3.6 Phosphoric acid:
3.6.1 Rust removal:
Phosphoric acid may be used as a "rust converter", by direct application to rusted
iron, steel tools, or surfaces. The phosphoric acid converts reddish-brown iron (III)
oxide, Fe2O3 (rust) to black ferric phosphate, FePO4.
"Rust converter" is sometimes a greenish liquid suitable for dipping (in the same sort
of acid bath as is used for pickling metal), but it is more often formulated as a gel,
commonly called naval jelly. It is sometimes sold under other names, such as "rust
remover" or "rust killer". As a thick gel, it may be applied to sloping, vertical, or
even overhead surfaces.
14
After treatment, the black ferric-phosphate coating can be scrubbed off, leaving a
fresh metal surface. Multiple applications of phosphoric acid may be required to
remove all rust. The black phosphate coating can also be left in place, where it will
provide moderate further corrosion resistance.
15
CHAPTER 4
WIRE DRAWING
Wire drawing is a metalworking process used to reduce the cross-section of
a wire by pulling the wire through a single, or series of, drawing die(s). There are
many applications for wire drawing, including electrical wiring, cables, tension-
loaded structural components, springs, paper clips, spokes for wheels, and stringed
musical instruments. Although similar in process, drawing is different
from extrusion, because in drawing the wire is pulled, rather than pushed, through
the die. Drawing is usually performed at room temperature, thus classified as a cold
working process, but it may be performed at elevated temperatures for large wires to
reduce forces. More recently drawing has been used with molten glass to produce
high quality optical fibres.
4.1 Process:
Fig. 4.1 Wire drawing concept
The wire drawing process is quite simple in concept. The wire is prepared by
shrinking the beginning of it, by hammering, filing, rolling or swaging, so that it will
fit through the die; the wire is then pulled through the die. As the wire is pulled
through the die, its volume remains the same, so as the diameter decreases, the length
16
increases. Usually the wire will require more than one draw, through successively
smaller dies, to reach the desired size. The American wire gauge scale is based on
this. This can be done on a small scale with a draw plate, or on a large commercial
scale using automated machinery. The process of wire drawing changes material
properties due to cold working.
The areal reductions of small wires are 15–25% and larger wires are 20–45%. Very
fine wires are usually drawn in bundles. In a bundle, the wires are separated by a
metal with similar properties, but with lower chemical resistance so that it can be
removed after drawing. If the reduction in diameter is greater than 50%, the process
may require annealing between the process of drawing the wire through the dies.
Commercial wire drawing usually starts with a coil of hot rolled 9 mm (0.35 in)
diameter wire. The surface is first treated to remove scales. It is then fed into either a
single block or continuous wire drawing machine.
Single block wire drawing machines include means for holding the dies accurately in
position and for drawing the wire steadily through the holes. The usual design
consists of a cast-iron bench or table having a bracket standing up to hold the die,
and a vertical drum which rotates and by coiling the wire around its surface pulls it
through the die, the coil of wire being stored upon another drum or "swift" which lies
behind the die and reels off the wire as fast as required. The wire drum or "block" is
provided with means for rapidly coupling or uncoupling it to its vertical shaft, so that
the motion of the wire may be stopped or started instantly. The block is also tapered,
so that the coil of wire may be easily slipped off upwards when finished. Before the
wire can be attached to the block, a sufficient length of it must be pulled through the
die; this is effected by a pair of gripping pincers on the end of a chain which is
wound around a revolving drum, so drawing the wire until enough can be coiled two
or three times on the block, where the end is secured by a small screw clamp or vice.
When the wire is on the block, it is set in motion and the wire is drawn steadily
through the die; it is very important that the block rotates evenly and that it runs true
and pulls the wire at a constant velocity, otherwise "snatching" occurs which will
weaken or even break the wire. The speeds at which wire is drawn vary greatly,
according to the material and the amount of reduction.
17
Continuous wire drawing machines differ from the single block machines in having a
series of dies through which the wire passes in a continuous manner. The difficulty
of feeding between each die is solved by introducing a block between each die. The
speeds of the blocks are increased successively, so that the elongation is taken up and
any slip compensated for. One of these machines may contain 3 to 12 dies. The
operation of threading the wire through all the dies and around the blocks is termed
"stringing-up".
The arrangements for lubrication include a pump which floods the dies, and in many
cases also the bottom portions of the blocks run in lubricant.
Fig. 4.2 High Speed Wire Drawing Machine
Often intermediate anneals are required to counter the effects of cold working, and to
allow further drawing. A final anneal may also be used on the finished product to
maximize ductility and electrical conductivity.
An example of product produced in a continuous wire drawing machine is telephone
wire. It is drawn 20 to 30 times from hot rolled rod stock.
18
While round cross-sections dominate most drawing processes, non-circular cross-
sections are drawn. They are usually drawn when the cross-section is small and
quantities are too low to justify rolling. In these processes, a block or Turk's-head
machine are used.
4.2 Lubrication:
Lubrication in the drawing process is essential for maintaining good surface finish
and long die life. The following are different methods of lubrication:
Wet drawing: the dies and wire or rod are completely immersed in lubricant.
Dry drawing: the wire or rod passes through a container of lubricant which coats
the surface of the wire or rod.
Metal coating: the wire or rod is coated with a soft metal which acts as a solid
lubricant.
Ultrasonic vibration: the dies and mandrels are vibrated, which helps to reduce
forces and allow larger reductions per pass.
Various lubricants, such as oil, are employed. Another lubrication method is to
immerse the wire in a copper (II) sulphate solution, such that a film of copper is
deposited which forms a kind of lubricant. In some classes of wire the copper is left
after the final drawing to serve as a preventive of rust or to allow easy soldering. The
best example of copper coated wire is in MIG wire or Co2 wire used in welding. The
steel wires are copper coated for lubrication.
4.3 Mechanical Properties:
The strength-enhancing effect of wire drawing can be substantial. The highest grule
strengths available on any steel have been recorded on small-diameter cold-drawn
austenitic stainless wire. Tensile strength can be as high as 400 ksi (3760 MPa).
19
4.4 Drawing dies:
Fig. 4.3 Carbide wire drawing die
Drawing dies are typically made of tool steel, tungsten carbide, or diamond, with
tungsten carbide and manufactured diamond being the most common. For drawing
very fine wire a single crystal diamond die is used. For hot drawing, cast-steel dies
are used. For steel wire drawing, a tungsten carbide die is used. The dies are placed
in a steel casing, which backs the die and allow for easy die changes. Die angles
usually range from 6 – 15 ° and each die has at least 2 different angles: the entering
angle and approach angle. Wire dies usually are used with power as to pull the wire
through them. There are coils of wire on either end of the die which pull and roll up
the wire with a reduced diameter.
20
CHAPTER 5
STRANDING
In the so-called cross lay strands, the wires of the different layers cross each other. In
the mostly used parallel lay strands, the lay length of all the wire layers is equal and
the wires of any two superimposed layers are parallel, resulting in linear contact. The
wire of the outer layer is supported by two wires of the inner layer. These wires are
neighbours along the whole length of the strand. Parallel lay strands are made in one
operation. The endurance of wire ropes with this kind of strand is always much
greater than of those (seldom used) with cross lay strands. Parallel lay strands with
two wire layers have the construction Filler, Seale or Warrington.
5.1 Number of strands
The more individual wire strands in a wire bundle, the more flexible, kink-resistant,
break-resistant, and stronger the wire is. But more strands cost more.
The lowest number of strands is 7: one in the middle, 6 surrounding it.
The next level up is 19, which is another layer of 12 strands on top of the 7. After
that the number varies, but 37 and 49 are common, then in the 70 to 100 range (the
number is no longer exact). Even larger numbers than that are typically found only in
very large wires.
For application where the wire moves, 19 is the lowest that should be used (7 should
only be used in applications where the wire is placed and then does not move), and
49 is much better. For applications with constant repeated movement, such as
assembly robots and headphone wires, 70 to 100 is mandatory.
For applications that need even more flexibility (welding is the usual example, but
also any need to move wire in tight areas), even more strands are used. One example
is a 2/0 wire made from 5,292 strands of #36 gauge wire. The strands are organized
by first creating a bundle of 7 strands. Then 7 of these bundles are put together into
super bundles. Finally 108 super bundles are used to make the final cable. Each
21
group of wires is wound in a helix so that when the wire is flexed, the part of a
bundle that is stretched moves around the helix to a part that is compressed to allow
the wire to have less stress.
Solid wire, also called solid-core or single-strand wire consists of one piece of metal
wire. Stranded wire is composed of a bundle of wires to make a larger conductor.
Stranded wire is more flexible than solid wire of the same total cross-sectional area.
Solid wire is cheaper to manufacture than stranded wire and is used where there is
little need for flexibility in the wire. Solid wire also provides mechanical ruggedness;
and, because it has relatively less surface area which is exposed to attack by
corrosives, protection against the environment. Stranded wire is used when higher
resistance to metal fatigue is required. Such situations include connections
between circuit boards in multi-printed-circuit-board devices, where the rigidity of
solid wire would produce too much stress as a result of movement during assembly
or servicing; A.C. line cords for appliances; musical instrument cables; computer
mouse cables; welding electrode cables; control cables connecting moving machine
parts; mining machine cables; trailing machine cables; and numerous others.
At high frequencies, current travels near the surface of the wire because of the skin
effect, resulting in increased power loss in the wire. Stranded wire might seem to
reduce this effect, since the total surface area of the strands is greater than the surface
area of the equivalent solid wire, but ordinary stranded wire does not reduce the skin
effect because all the strands are short-circuited together and behave as a single
conductor. A stranded wire will have higher resistance than a solid wire of the same
diameter because the cross-section of the stranded wire is not all copper; there are
unavoidable gaps between the strands (this is the circle packing problem for circles
within a circle). A stranded wire with the same cross-section of conductor as a solid
wire is said to have the same equivalent gauge and is always a larger diameter.
However, for many high-frequency applications, proximity effect is more severe than
skin effect, and in some limited cases, simple stranded wire can reduce proximity
effect. For better performance at high frequencies, litz wire, which has the individual
strands insulated and twisted in special patterns, may be used.
22
CHAPTER 6
PACKING
It is done by Packing Machine, which works automatically with controlled
overlapping. Tag printing is also done by the machine.
The packing procedure followed known as “Seaworthy packing procedure”.
6.1 Seaworthy Packing Procedure:
The seaworthy packing procedure article provides you information about packing
procedure which needs to withstand the conditions of maritime transport.
Fig. 6.1 Seaworthy Packing
23
The term seaworthy packaging procedure is intended to indicate that the packaging
must additionally strengthen and withstand the conditions of maritime transport and
then resist to more severe stresses.
But you may note the most severe stresses do not occur during maritime transport
itself, but instead during cargo handling (due to impact, pushing, overturning etc.).
In below you can see a draft of seaworthy packing procedure which can be used for
industrial goods:
6.1.1 Seaworthy Packing Procedure - Vendor’s Obligations and
Responsibilities:
VENDOR shall be solely responsible for packing and marking of CARGO with
respect to handling, transport, and storage at plant site. VENDOR shall be fully liable
for proper, sufficient and adequate packing, completeness of contents, protection of
contents for a storage time of 6 months, and correct preparation of the packing list.
All damage and costs whatsoever resulting from inadequate or insufficient packing
shall be fully charged to VENDOR.
Packing and conservation of goods shall be sufficient to protect them from damage
during transit from point of manufacturer and storage at job SITE under conditions
which may involve multiple handling, extended storage, exposure to moisture and
the possibility of pilferage. The content must withstand 1 year transit conditions
without suffering damage and VENDOR shall give recommendations for further
two-year storage under SITE conditions. Required storage facilities and procedures
shall be advised by VENDOR in advance.
6.1.2 Seaworthy Packing Procedure - Steel Structure and Plates:
Pipe, structural steel sections and plates, shall be strapped in bundles of convenient
size and weight for handling. Rolled and shaped plates shall be provided with
suitable bracing to eliminate distortion during transit, and shall be bundled in
uniform lengths. The weight of each bundle shall be within the braking strain of the
steel wrapping. Each bundle shall be marked with a metal tag, hard stamped, secured
24
under steel wrapping. A 2000 kg limitation shall be imposed for lifts in this category.
Where practicable, lengths shall be limited to 11.5 meters to avoid long carrier. All
small steel sectional handrail stanchions, gusset plates etc. shall be boxed.
Applications
Power:
Transmission Lines
Construction:
Pre-stressed concrete girders for road, river & railway bridges & flyovers.
Automobile:
Spring
Hydraulic Crane
General Engineering:
Fasteners
Cycles
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CONCLUSION
The Ramsarup Industries Ltd. is one of the largest run industries in India. It gives
employment to a large number of the people. It is a big organization working in
profit and it is really a good achievement. The working culture is quite good .The
Engineers along with supervisors and labours work as a team to complete a task. The
satisfaction of customers is top most priority of the Company.
The Ramsarup Group believes in providing best quality to their customers.
It was a good experience to work as a trainee at Ramsarup Industries Ltd.
26
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1. Eagleson, Mary (1994), concise encyclopaedia chemistry (revised ed.),
Walter de Gruyter, p. 834, ISBN 978-3-11-011451-5.
2. Liu, David; Lipták, Béla G. (1997), Environmental engineers' handbook,
CRC Press, p. 973, ISBN 978-0-8493-9971-8.
3. Fisch, Arline M. (2003), Textile Techniques in Metal: For Jewellers, Textile
Artists & Sculptors, Lark Books, p. 32, ISBN 978-1-57990-514-9.
4. Rao, S. Ramachandra (2006), Resource recovery and recycling from
metallurgical wastes, Elsevier, pp. 179–180, ISBN 978-0-08-045131-2.
5. McCoy's RCRA Unravelled (2005 ed.), McCoy and Associates, 2005,
p. 204, ISBN 0-930469-32-1.
6. International Iron and Steel Institute; Jones, Tim (1997), Steel industry and
the environment: technical and management issues, UNEP/Earth print,
p. 76, ISBN 978-92-807-1651-1.
7. Wang, Hung & Shammas 2009, p. 1193.
8. Chisholm, Hugh, ed. (1911). "Wire". Encyclopaedia Britannica (11th ed.).
Cambridge University 2.Press Davis, Joseph R; Handbook Committee, ASM
International (2001-08-01).
34
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