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INTRODUCTION eavy Mechanical Complex (Private) Limited is a leading engineering goods manufacturing enterprise in Pakistan located at Taxila about 30 Kilometers north of capital Islamabad. It is a professionally managed progressive organization with over 160,000 sq. meters covered facilities and 1,100 employees. H HMC have the resources to handle large projects with demanding delivery schedules. Being the largest and most extensive fabrication and machining facility equipped with state of the art technology. HMC provide manufacturing services both on our own or customers design. HMC have gained rich experience in designing and manufacturing of large projects through collaboration with internationally reputed engineering organizations. All its processing facilities are in- house including Designing, Fabrication, Machining, Iron and Steel Castings, Forgings, Heat Treatment, Assembly, Sand Blasting, Painting and Galvanizing etc. HMC is ISO 9001 certified and is authorized to use 4 ASME stamps U, U2, S & PP for equipment manufactured according to ASME code. The manufacturing is backed by excellent quality control and testing facilities to meet the product and customer quality requirements. 3rd party inspection facilities are also available, where required. INTERNSHIP REPORT ON HMC Page 1

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Page 1: Internship Report Hmc

INTRODUCTION

eavy Mechanical Complex (Private) Limited is a leading engineering goods

manufacturing enterprise in Pakistan located at Taxila about 30 Kilometers north of

capital Islamabad. It is a professionally managed progressive organization with over 160,000 sq.

meters covered facilities and 1,100 employees.

H

HMC have the resources to handle large projects with demanding delivery schedules. Being the

largest and most extensive fabrication and machining facility equipped with state of the art

technology. HMC provide manufacturing services both on our own or customers design.

HMC have gained rich experience in designing and manufacturing of large projects through

collaboration with internationally reputed engineering organizations. All its processing facilities

are in-house including Designing, Fabrication, Machining, Iron and Steel Castings, Forgings,

Heat Treatment, Assembly, Sand Blasting, Painting and Galvanizing etc.

HMC is ISO 9001 certified and is authorized to use 4 ASME stamps U, U2, S & PP for

equipment manufactured according to ASME code. The manufacturing is backed by excellent

quality control and testing facilities to meet the product and customer quality requirements. 3rd

party inspection facilities are also available, where required.

Heavy Mechanical Complex Ltd. (HMC), Taxila is a major heavy engineering subsidiary of the

State Engineering Corporation (SEC) under the Ministry of Industries & Production,

Government of Pakistan.

HMC defines itself as “A technical institute in which all types of machines including Sugar

plants, Cement Plants, Road rollers, Over Head Cranes ranging from 0.5 to 50 tons Heat

Exchanger boilers, Special Defense parts (i.e., NDC works), Special Vibratory Rollers (which

can bear statistically 10 to 12 tons vibratory load) and Pakistan steel

works. Some other processes that are also done by HMC are Designing and manufacturing and

assembling and installation with the certification of ISO – 9001.

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The Heavy Mechanical Complex (HMC), the biggest undertaking of its type in Pakistan, was

established in 1979 with Chinese assistance. The Heavy Forge Factory (HFF) at this complex has

proved crucial for Pakistan's defense production needs. HMC has the capability for designing,

engineering and manufacturing of industrial plants and machinery. HMC has the largest

fabrication and machining facilities in the country equipped with Computer Aided Designing

(CAD) and can undertake a variety of fabrication / machining jobs on sub-contracting basis.

HMC manufactures equipment for hydro-electric power plants, thermal power plants, sulphuric

acid plants, industrial alcohol plants, oil & gas processing plants, and chemical & petro-chemical

plants, etc. Boilers, cranes, construction machinery, material handling equipment, steel structure,

railway equipment, etc. are some of the other products which are produced on regular basis. The

company's capabilities include engineering and manufacturing of Sugar Mills ranging between

1,500 - 12,000 TCD (tons of cane crushing capacity per day), Portland Cement Plants of 700-

5,500 TPD (tons per day) module and White Cement Plant of 50 - 1,000 TPD.

WORKING STAFF

HMC is a professionally managed progressive organization with 1,100 employees.

HMC has a total covered area of 160,000 square feet.

FACTORIES AT HEAVY MECHANICAL COMPLEX

        Heavy mechanical complex I (HMC I)

        Heavy forge and foundry works (HMC II)

        Heavy mechanical complex III (HMC III)

Of these the last one is directly under the ministry of defense while the former two are governed

by ministry of production.

 

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QUALITY POLICY OF HMC

HMC states its quality policy as follows:

            “Quality performance is committed to excellence by each company employee. It is

achieved by team work and through a process of continuous improvement.”

            “We are dedicated to being seen as an organization which provides quality products and

services which meet or exceed the expectations of our customers.”

FACILITIES AT HMC

There are several shops in HMC industry.

 

Design department

Production planning and control (PPC)

Sales department /(PMD i.e. Project Management Department)

Accounts Finance and Administration

 Machine shop

Heat treatment shop

Fabrication shop

Forging shop

Hydraulic press shop

Steel foundry

Cast iron foundry

Pattern shop

Maintenance shop

Quality control

 

 

 

 

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PRODUCTION CAPACITY

Machining capacity = 500ton *12 months

Fabrication and Machining capacity= 1000ton *12months

Total = 500*12 + 1000*12 = 6000 tons per annum

This production capacity can be increased time to time with the extension of man power and

other sources subjecting to sub contractors.

HMC PRODUCTS RANGE

HMC specializes in Engineering, Designing, Manufacturing, Installation and Commissioning of

plants and machinery including;

    

Cement Plant and Spares:         600-5000 TPD

Sugar Plant and Spares:            500-12000 TCD

Process Plant Equipment: Pressure Vessels, Columns, Heat Exchangers, Drums, Storage Tanks

and Kilns

Chemical & Petro-Chemical Plants: Sulphuric Acid Plant, Basic Chromium Sulphate Plant,

Industrial Alcohol distillery, Gas Dehydration, LPG/LNG, Gas Purification & Sulphur Recovery

Plants.

Industrial Boilers: Fire tube Package units, water tube package units, heat recovery boilers,

begasse fire boilers (capacity up to 200 T/hr

Thermal Power Plants: Equipment for utility boilers, membrane wall, turbine/generator parts.

Hydral Power Plants: Gates, penstocks, wicket gates, head covers, turbine/generator parts

Cranes: Electric overhead travelling crane, portal & mobile cranes.

Road Construction Machinery: Static & vibratory road rollers, asphalt mixing plant.

Steel Structures: For thermal power plants, process plants etc.

Railways Equipment: Railway axles, surface troverser, screw coupling & screw jack.

Castings: Iron & steel castings as per specifications

Forgings: Shafts, rings and others as per specifications

Automotive Forging: For tractors and other automobile

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PRODUCTION PLANNING & CONTROL  

The PPC department has been organized with the objective of improving company’s

performance. The dept is headed by a Dy. GM incharge PPC and comprises of the following

sections:

 

        Core planning / Data processing

        Project planning

        Material management

A.     Material management section (MMG)

B.     General store

        Production technology

A.     Feasibility / quantitative detail

B.     Process planning

C.     Tool designing

        Dispatch cell / Material handling

A.     Material handling store (MHC)

B.     Dispatch cell

        Income tax custom rebate (ICR)

 

1. SALES ORDER NUMBERING SYSTEM

 

The sales order numbering system allocates a unique identification system to each order acquired

by the sales and marketing department. This sales order consists of six digits. The first two of

these numbers designate the product group number of the products to be manufactured or

services to be provided by the organization. The next two digits specify the fiscal year in which

the order is received and the last two digits give the number of similar orders already received in

the same fiscal year.

For example,  a job order given as 11-10-04 is read as follows

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11_______ product group no for sugar spares

10_______represents 2010 as the fiscal year

04_______specifies the fourth order for the current year

 

That is fourth order of sugar spares in 2010.

 

2. CORE PLANNING SECTION        

               

        Master schedule planning

        Order activity planning

        Monitoring all schedules / shop scheduling

        Preparing various reports for MIS

        Maintenance of balance order position.

        Monthly sales and production reports

        Sales / production budget.

        Project review. Meeting and follow up.

        Data entry, loading data and processing data

 

3. PROJECT PLANNING SECTION

 

        To ensure receipts of all drawings and documentation from design as per contact and

accelerate the schedule for production and procurement.

        To issue “material purchase requirement” to MMG.

       To prepare “bill of material” to be purchased.

       To co ordinate with the production technology for preparation of necessary

documents for production.

        To prepare and issue job orders and follow up.

        To suggest alternate materials from stock to design.

        To prepare data and reports for ICR and for survey by CBR.

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4. MATERIAL MANAGEMENT

A. MMG Section:

        Material requirement planning.

        Indenting and follow up of indents.

        To keep update purchase status for all the project demands.

        Establish stock levels for general consumable items and raw materials.

        Issuance of materials to the appropriate job.

        To keep and maintain update levels for the store items.

        To look after stores and related things.

 

B. General Store:

 

        To receive, issue all the materials, and equipment in stotes as per laid down

procedure.

        Maintain detailed record of store movements.

        Maintain stock location system.

        Maintain daily submission of issue and receipt statement to concerned dept.to keep

store areas secure and organized.

 

5. PRODUCTION TECHNOLOGY

 

Feasibility/Quantitative Detail:

      Feasibility study and quantitative details of clients requirements for cost estimate.

 

Process Planning:

      Prepare details per list, route cards, cutting plans, time sheets and process maps for

all the processes.

 

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Tool Designing:

      Designing of all types of press tools, dies, templates, jigs and fixtures.

      Prepare drawings for machinery components, cutting planes, marking templates for

shops etc.

 

6. DISPACH CELL

        To receive finished jobs from shops.

        To draw standard items from store for dispatch to customer.

        To organize packing etc.

        To organize transportation.

        Ensure complete accurate documentation with each product.

 

 

 

 

 

______________________________________________

 

 

 

 

 

 

 

 

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MACHINE SHOP

Machine shop at HMC has following machines

        Gear shaper machine

        Straight bevel machine

        Gear hobbing machine

        Vertical turret lathe machine

        Horizontal lathe machine

        Horizontal vertical slope type boring and milling machine.

        Universal boring, milling, facing, threading, taping machine.

        Plano milling machine.

        Horizontal boring machine.

        Redial drilling machine.

        Column drilling machine.

        Gear shaper tool machine

        Slotting machine

        BVT boring vertical turret machine

        Face plat lathe machine.

        Double housing planne

        Vertical milling machine.

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Gear Shaper

A gear shaper is a machine tool for cutting the teeth of internal or external gears. The name

shaper relates to the fact that the cutter engages the part on the forward stroke and pulls away

from the part on the return stroke, just like the clapper box on a planer shaper. To cut external

teeth, a different machine called a hobbing machine can be used.

Spur Gears

They connect parallel shafts, have involute teeth that are parallel to the shaft and can have

internal or external teeth. They cause no external thrust between gears. They are inexpensive to

manufacture. They give lower but satisfactory performance. They are used when shaft rotates in

the same plane.

 Helical Gears

Helical gears connect parallel shifts but the involute teeth are cut at an angle to the axis of

rotation. Two mating helical gears must have equal helix angle but opposite hand. They run

smoother and more quietly. They have higher load capacity, are more expensive to manufacture

and create axial thrust. They have longer and strong teeth. They can carry heavy load because of

the greater surface contact with the teeth. The efficiency is also reduced because of longer

surface contact. The gearing is quieter with less vibration.

 Internal Gears

Internal gears are hollow. The properties and teeth shape is similar as of external gears except

that the internal gear had different addendum and dedendum values modified to prevent

interference in internal meshes. They are designed to accommodate a wide range of equipment.

These are ideal and cost effective. The teeth are cut into the inside diameter while the outside

diameter is smooth. These gears are available only in brass. Internal gear offers low sliding and

high stress loading. They are used in planetary gears to produce large reduction ratios.

When choosing a mating gear the difference between the number of teeth of girth gear and the

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pinion should not be less than 15. Their non-binding tooth design ensures smooth, quiet

operation. They are used to transmit rotary motion between parallel shafts, the shaft rotating in

the same direction as the arrangement.

 Worm Gears

The Worm gear is the heart of most mills and kiln drive system. They can't be used in spare parts

inventory. They are also used in steel industry, sugar industry, paper and pulp industry. The girth

gear has been preferred over the gearless drives due to their lower initial cost, simplicity to

install, operate and maintain.

 Hobbing

Hobbing is a machining process for making gears, on a hobbing machine, which is a special type

of milling machine .The teeth or spines are progressively cut into the workpiece by a series of

cuts made by a cutting tools called a hob. Compared to other gear forming processes it is

relatively inexpensive but still quite accurate, thus it is used for a broad range of parts and

quantities.

It is the most widely used gear cutting process for creating spur and helical gears and more gears

are cut by hobbing than any other process since it is relatively quick and inexpensive. 

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HEAT TREATMENT AND TTC (TECHNICAL

TRAINING CELL)

Heat Treatment – The Processes

Annealing

Normalizing

Hardening

      Surface

      Full

      Case

Tempering

Stress releasing

Carburizing

      Gas

      Pack

Phosphating

 

Heat treatment

 

“Heat Treatment is the controlled heating and cooling of metals to alter their physical and

mechanical properties without changing the product shape.”

Annealing

Annealing, in metallurgy and materials science, is a heat treatment wherein a material is altered,

causing changes in its properties such as strength and hardness. It is a process that produces

conditions by heating to above the re-crystallization temperature and maintaining a suitable

temperature, and then cooling. Annealing is used to induce ductility, soften material, relieve

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internal stresses, refine the structure by making it homogeneous, and improve cold working

properties.

Normalizing

 

Annealing, in metallurgy and materials science, is a heat treatment wherein a material is altered,

causing changes in its properties such as strength and hardness. It is a process that produces

conditions by heating to above the re-crystallization temperature and maintaining a suitable

temperature, and then cooling. Annealing is used to induce ductility, soften material, relieve

internal stresses, refine the structure by making it homogeneous, and improve cold working

properties.

 

In the cases of copper, steel, silver, and brass this process is performed by substantially heating

the material (generally until glowing) for a while and allowing it to cool slowly. In this fashion

the metal is softened and prepared for further work such as shaping, stamping, or forming.

 

Hardening

 

Flame Hardening:

A high intensity oxy-acetylene flame is applied to the selective region. The temperature is raised

high. The "right" temperature is determined by the operator based on experience by watching the

color of the steel. The overall heat transfer is limited by the torch and thus the interior never

reaches the high temperature. The heated region is quenched to achieve the desired hardness.

Tempering can be done to eliminate brittleness.

Induction Hardening:

In Induction hardening, the steel part is placed inside a electrical coil which has alternating

current through it. This energizes the steel part and heats it up. Depending on the frequency and

amperage, the rate of heating as well as the depth of heating can be controlled. Hence, this is

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well suited for surface heat treatment. The Induction and flame hardening processes protect areas

exposed to excessive wear.

Items that we induction harden include Spur Gears and Spur Pinions ,Helical Gears and Helical

Pinions ,Sprockets ,Internal Gears ,Bevel Gears ,Shafts and Pins ,Rails and Racks ,Wheels and

Rollers Sheave Wheels ,Links ,Axle Boxes and Bushes ,

Tempering:

Tempering is a heat treatment technique for metals, alloys and glass. In steels, tempering is done

to "toughen" the metal by transforming brittle martensite into bainite or a combination of ferrite

and cementite. Precipitation hardening alloys, like many grades of aluminum and superalloys,

are tempered to precipitate intermetallic particles which strengthen the metal. Tempering is

accomplished by a controlled reheating of the work piece to a temperature below its lower

critical temperature.

 

The brittle martensite becomes strong and ductile after it is tempered. Carbon atoms were

trapped in the austenite when it was rapidly cooled, typically by oil or water quenching, forming

the martensite. The martensite becomes strong after being tempered because when reheated, the

microstructure can rearrange and the carbon atoms can diffuse out of the distorted BCT structure.

After the carbon diffuses, the result is nearly pure ferrite.

 

Stress Releasing:

stress releasing is used to reduce residual stresses in large castings, welded parts and cold-

formed parts. Such parts tend to have stresses due to thermal cycling or work hardening. Parts

are heated to temperatures of up to 600 - 650 ºC (1112 - 1202 ºF), and held for an extended time

(about 1 hour or more) and then slowly cooled in still air

 

 Carburizing:

Carburizing, also known as carburization, is a heat treatment process in which iron or steel is

heated in the presence of another material (but below the metal's melting point) which liberates

carbon as it decomposes. The outer surface or case will have higher carbon content than the

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original material. When the iron or steel is cooled rapidly by quenching, the higher carbon

content on the outer surface becomes hard, while the core remains soft and tough.[1]

 

This manufacturing process can be characterized by the following key points: It is applied to

low-carbon workpieces; workpieces are in contact with a high-carbon gas, liquid or solid; it

produces a hard workpiece surface; workpiece cores largely retain their toughness and ductility;

and it produces case hardness depths of up to 0.25 inches (6.4 mm).

 

Phosphating:

Phosphate coatings are used on steel parts for corrosion resistance, lubricity, or as a foundation

for subsequent coatings or painting. It serves as a conversion coating in which a dilute solution

of phosphoric acid and phosphate salts is applied via spraying or immersion, chemically reacts

with the surface of the part being coated to form a layer of insoluble, crystalline phosphates.

Phosphate conversion coatings can also be used on aluminium, zinc, cadmium, silver and tin.

 

The main types of phosphate coatings are manganese, iron and zinc. Manganese phosphates are

used both for corrosion resistance and lubricity and are applied only by immersion. Iron

phosphates are typically used as a base for further coatings or painting and are applied by

immersion or by spraying. Zinc phosphates are used for rust proofing (P&O), a lubricant base

layer, and as a paint/coating base and can also be applied by immersion or spraying.

 

 

 

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LIST OF APPARATUS

 

Electric Furnaces:-

 

1. Car bottom furnace

Max. temp = 950oC

Size            =900 x 700 x 1800

Plotter and temperature indicator is attached with it.

 

2. Box type air furnace

It is small and large.

Max. temp = 950oC

Size            =600 x 500 x 1200

 

Max. temp = 950oC

Size            =450 x 450 x 950

 

3. Pit type tempering furnace

Max. temp = 950oC

 

4. Salt bath furnace

Small, medium, large

Temp = 550-650oC

Size            =300 x 400 x 500

 

Temp = 700-900oC

Size            =300 x 400 x 800

 

Temp = 1050-1270oC

Size            =200 x 300 x 800

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5. Flame quenching plant

Vertical      : φ1200 x 600

Horizontal   : φ 450 x 2400

 

6.High frequency induction machine

It is in isolated room, it uses 10,000 volts. It have a copper ring that induct heat to the

component’s external part, it have a mechanism of movement of job and quenching. Room is

provided with oil and water drum for the purpose of quenching.

 

7.   Cleaner

It is use to wash salt from metal surface after sand bathing.

8.Manual Straightening Press

It is used to straight long and thin metallic sheets.

 

9.   Electric gas carburizing furnace

Temp = 950oC

Size      =φ 300 x 600

 

10.   Electric tempering furnace

Temp = 650oC

Size      =φ950 x 1220

11. Salt bath

Size      =2000 x 2000 x 1400

 

12. Water quenching tank

Size      =1500 x 3000 x 3000

 

  

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CTC Fabrication Shop  

CTC stands for Central Technical Cell. Basically it is a drawing and planning section of

fabrication shop, in this section different drawings are analyzed and then sent to different

sections of fabrication shop depending upon the job and capacity of the shop.

The main jobs of CTC fabrication are

 

       Job feeding to shop

       Planning

       Material check

       Observation from manufacturing till sale.

 

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FABRICATION SHOP  

Basically Fabrication Shop is divided into four sections:

        Heavy bay section,

        Medium bay section,

        Small bay section

        Marking and layout section

 

LIST OF APPARATUS AND MACHINES

 

The machines in the fabrication shop and their capacities are given below:

 

SMALL BAY

         2.5 ton press

         5 ton bending machine

 

 

MEDIUM BAY

         Shaft cutting Circular saw

Cutting Dia 1350mm

 

         Shaft welding machine

Height of beam 450mm

HEAVY BAY

         3000 ton press

         1000 ton rolling machine

         50 ton capacity cranes

 

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MARKING LAYOUT AND CUTTING SECTION

 

        Photo cell cutting machine

Electromagnetic or paper templates are used

         CNC cutting machine

A German CNC cutting machine is used for cutting accurate and complex

parts

         Plasma arc cutting machine for non ferrous metals

         Semi automatic cutting machine

Oxygen and natural gas are used for cutting

         Mechanical cutting machine(shearing machine)

         Parallel cutting machine

         Trennjaeger machine

         Nine roller

         Straightening machine

 

Welding

 

Mainly welding is done in all bays of fabrication shop. The type of welding used in fabrication

shop is as follows:

 

1.     Arc Welding:

 

Arc welding uses a welding power supply to create an electric arc between an electrode and

the base material to melt the metals at the welding point. They can use either direct (DC) or

alternating (AC) current, and consumable or non-consumable electrodes. The welding region

is sometimes protected by some type of inert or semi-inert gas, known as a shielding gas,

and/or an evaporating filler material. The process of arc welding is widely used because of its

low capital and running costs.

 

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2.     Shielded Metal Arc Welding (SMW):

 

Shielded metal arc welding (SMAW), also known as manual metal arc (MMA) welding or

informally as stick welding, is a manual arc welding process that uses a consumable

electrode coated in flux to lay the weld. An electric current, in the form of either alternating

current or direct current from a welding power supply, is used to form an electric arc between

the electrode and the metals to be joined. As the weld is laid, the flux coating of the electrode

disintegrates, giving off vapors that serve as a shielding gas and providing a layer of slag,

both of which protect the weld area from atmospheric contamination.

 

Because of the versatility of the process and the simplicity of its equipment and operation,

shielded metal arc welding is one of the world's most popular welding processes. It

dominates other welding processes in the maintenance and repair industry, and though flux-

cored arc welding is growing in popularity, SMAW continues to be used extensively in the

construction of steel structures and in industrial fabrication. The process is used primarily to

weld iron and steels (including stainless steel) but aluminum, nickel and copper alloys can

also be welded with this method.

3.     Tungsten Inert Gas Welding:

 

Gas tungsten arc welding (GTAW), also known as tungsten inert gas (TIG) welding, is an arc

welding process that uses a no consumable tungsten electrode to produce the weld. The weld

area is protected from atmospheric contamination by a shielding gas (usually an inert gas

such as argon), and a filler metal is normally used, though some welds, known as autogenous

welds, do not require it. A constant-current welding power supply produces energy which is

conducted across the arc through a column of highly ionized gas and metal vapors known as

plasma.

 

 

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GTAW is most commonly used to weld thin sections of stainless steel and light metals such

as aluminum, magnesium, and copper alloys. The process grants the operator greater control

over the weld than competing procedures such as shielded metal arc welding and gas metal

arc welding, allowing for stronger, higher quality welds. However, GTAW is comparatively

more complex and difficult to master, and furthermore, it is significantly slower than most

other welding techniques. A related process, plasma arc welding, uses a slightly different

welding torch to create a more focused welding arc and as a result is often automated.

 

4.     Metal Inert Gas Welding:

 

Gas metal arc welding (GMAW), sometimes referred to by its subtypes metal inert gas

(MIG) welding or metal active gas (MAG) welding, is a semi-automatic or automatic arc

welding process in which a continuous and consumable wire electrode and a shielding gas

are fed through a welding gun. A constant voltage, direct current power source is most

commonly used with GMAW, but constant current systems, as well as alternating current,

can be used. There are four primary methods of metal transfer in GMAW, called globular,

short-circuiting, spray, and pulsed-spray, each of which has distinct properties and

corresponding advantages and limitations. 

WELDING DEFECTS

 

Defect found in the welding are

Cracks                                                     Blow holes

Crack                                                      Spatter

Lack of penetration                                Undercut

Pipes                                                       Tungsten inclusion

Porosity                                                   Restart of welding

Lack of fusion

        Slag inclusions

  

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NON DESTRUCTIVE TESTING LAB

 

Non destructive test is used to identify the defects in welding joints in the NDT lab of HMC

 

NON DESTRUCTIVE EXAMINATION FACILITIES

x-ray radiography

Gamma ray radiography

Ultrasonic

Magnetic particle

Liquid penetrant

Eddy current

Spectroscopy

 

RADIOGRAPHY TECHNIQUES

 

Following Radiography techniques are possible, but only three type of radiography are used

mostly X-ray, ultrasonic, and gamma ray radiography because other radiography are expensive.

A list of available radiographic methods is given below:

X-ray Radiography

Gamma Ray Radiography

Neutron Radiography

Proton Radiography

Xero Radiography

Fluoroscopy

Micro Radiography

Flash Radiography

Auto Radiography

Electron transmit Radiography

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NDT METHDS APPLICATION AND LIMITATIONS

 

        Radiography testing Method.

1.      Radiography is the most universally used NDT method for detection of gas porosity

in the weldments.

 

2.      The radiography image of a “Round Porosity” will appear as oval shaped spots with

smooth edges, while “elongated porosity” will appear as oval shaped spots with major

axis. Sometimes several time longer then minor axis.

 

3.      Foreign material such as loose scale, flux or splatter will affect validity of test results.

 

        Ultrasonic Testing Method

 

1.      Ultrasonic testing equipments are highly sensitive, capable of detecting micro

separations.

2.      Surface finishing and grain size will affect the validity of the test.

 

        Eddy current Testing Method

 

1.      Normally confined to thin wall welded pipes and tube.

2.      Penetration restricts testing to a depth of more than one quarter inch.

 

        Liquid Penetrant Testing Method

 

a.       Normally confined to in processes control of ferrous and non ferrous welds.

b.      Liquid penetrant testing is like magnetic particle is restricted to surface

evaluation.

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c.       Extreme condition must be exercised to prevent any cleaning material and

liquid penetrant materials from becoming entrapped  and contaminating the

rewelding operation.

 

        Magnetic particle Testing Method

 

Normally used to detect gas porosity .Only surface porosity would be evident. Near

surface porosity would not be clearly defined, since indications are neither strong nor

pronounced.

 

 

 

 

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FORGING SHOP  

“Forging is the term for shaping metal by using localized compressive forces.”

 

Cold forging is done at room temperature or near room temperature. Hot forging is done at a

high temperature, which makes metal easier to shape and less likely to fracture. Warm forging is

done at intermediate temperature between room temperature and hot forging temperatures.

Forged parts can range in weight from less than a kilogram to 170 metric tons. Forged parts

usually require further processing to achieve a finished part.

 

PROCESSES OF FORGING

 

        Open-die drop-hammer forging

        Impression-die drop-hammer forging

        Press forging

        Upset forging

        Automatic hot forging

        Net-shape and near-net-shape forging

        Induction forging

 

Of these the first three methods are commonly used in HMC

FUNCTIONS OF FORGE SHOP

 

        Production of large and medium size forgings.

        Mostly forged parts include railway axles, draw hooks, screw couplings, cement and

sugar plant parts, boiler components, road rollers parts, cranes and drop tank equipments.

        Its annual production is 4500 tons.

 

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FORGING EQUIPMENT

HAMMERS:

        150kg pneumatic hammer

        400kg pneumatic hammer

        750kg pneumatic hammer 

HYDRAULIC PRESSES:

        800 ton drawdown type press along with pump, accumulator station and forging

manipulator. 

DIE FORGING PRESSES:

        60 ton power press

        160 ton friction press

        400 ton power press

        1250 ton friction press.

CRANES:

        1 ton stationary stewing crane

        5 ton quenching overhead crane

        12.5 ton overhead crane

        20.5 ton forging crane

OTHER APPLIANCESL

        Shot blasting machine

        Pedestal grinder

        Quenching tanks_____ 2 oil and water (5m* 3m* 5m each) 

FURNACES

        Heating furnaces           ________ 10

4.84m* 2.08m* 1.5m

Max temp 1300 degree Celsius

        Heat treatment furnace ________ 5

15m* 4m* 6m

Max temp 1050 degree Celsius

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PATTERN SHOP  

The purpose of pattern shop is to make wooden or metallic components for casting process.

 

TYPES OF PATTERN

 

        One piece or solid pattern

        Two piece or split pattern

        Three piece pattern

        Loose piece pattern.

        Self core pattern.

        Sweep pattern.

        Skeleton pattern.

        Match plate pattern.

        Connecting pattern.

        Master pattern

 

TYPES OF CORE PRINTS

 

        Top print.

        Bottom print.

        Side print.

        Tail print.

        Hang print.

        Balancing print.

 

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TYPES OF CORE BOX

 

        Box type core box.

        Shake out type core box.

        Gang type core box

 

MACHINES IN PATTERN SHOP

 

        Band saw.

        Joint planner.

        Thickness planner.

        Disc and spindle sander.

        Wooden lathe machine.

        Wooden milling machine.

 

 

 

 

 

 

 

 

 

 

 

 

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MATERIAL TESTING LABORATORY  

The objective of material testing laboratory is to check the chemical composition of different

alloys of iron, copper as well as other non metallic elements. The facility contains the following

laboratories:

 

        Quick response section.

        Mechanical testing section

        Heat treatment section

        Microscope section

        Wet test laboratory

 

QUICK RESPONSE SECTION

 

The quick response section is situated near the steel foundry and it helps the foundry men to melt

different alloys in exact element ratios to get specific allows. It has the facility to inspect the

molten metal from the furnace at intervals and provide the feedback within a few minutes. The

facility has the following apparatus:

        Emission spectrometer.

        Spectrophotometer.

        Carbon furnace.

        Titration apparatus.

 

EMISSION SPECTROMETER

This instrument vaporizes the metal by producing an electric spark and then analyses the

spectrum of the resulting vapors to identify the percentage of 26 different metals in the given

alloy. It has the capability to detect both iron based and copper based metals. The elements that

are detected by it include the following:

 

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Carbon, silicon, manganese, phosphorus, sulphur, chromium, molybdenum, aluminum, copper,

cobalt, titanium, vanadium, tungsten, lead, boron, tin, zinc, arsenic, bismuth, calcium, cesium,

zirconium, and iron.

 

MECHANICAL TESTING SECTION

 

This testing section includes the following machines:

      Universal testing machine

      Impact test machine

      Brinnel hardness testing machine

      Rockwell hardness tester and Vickers

      Wear testing machine

 

WET TEST LABORATORY

 

In the wet test laboratory, we use the element analysis to measure the moisture contents in any

material or a specimen or element.

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