CHAPTER 1

INTRODUCTION

1.1 ORIGIN OF COMPANY

Hindustan Zinc Limited was incorporated from the east while Metal Corporation of India

on 10 January 1966 as a Public Sector Undertaking. In accordance with the govt. philosophy, the

govt. took over the working of metal coloration of India, which was associated with the production

of major nonferrous metals like Zinc Lead & created HUNDUSTAN ZINC LIMITED on January

10, 1966 to further explore & developed the mining & smelting capacity of these metals.

1.2 GROWTH

Starting with one mine producing only 500 tones per day lead, zinc ore, 3600 tones per

annum lead smelter & 18000 tones per annum zinc smelter under construction in 1966. Today, The

Company has been declared a "Mini Ratna".The authorized share capital of HZL is Rs. 500 crores.

The paid up capital is Rs. 422.53 crores.. The Government holds 76% of the equity. The

Government has recently decided to disinvest further 25% of its equity in the domestic market to

small investor and employees of the company. HZL, with its headquarters at Udaipur, operates five

lead-zinc Mines with a total lead-zinc ore production capacity of 3.49 million tones per annum

(tpa) and four smelters with combined installed capacity of 152,000 tpa zinc 43.000 tpa lead.

Table 1: ore production capacity of HZL mines (in tpa )

Mines Ore capacity

Zawar Group of Mines District Udaipur (Rajasthan) 4000

Rajpura-Dariba Mine, District Rajsamand (Rajasthan) 2400

Rampura Agucha Mine, District Bhilwara (Rajasthan) 4500

Sargipali Lead Mine, District Sundergarh (Orissa) 500

Agnigundala Lead Mine, District Guntur (Andhra Pradesh) 240

Maton Rock Phosphate Mine, District Udaipur (Rajasthan) 600

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Table 2: Smelter wise Metal Production Capacity (in tpa)

Smelters Metal capacity

zinc lead

Debari Zinc Smelter, District Udaipur (Rajasthan)

Metal Capacity Zinc.

49,000

Vizag Zinc & Lead Smelter, District Visakhapatnam(Andhra Pradesh) 33,000 22,000

Chanderiya Lead-Zinc 70,000 Smelter, District Chittorgarh (Rajasthan) 70,000 35,000

1.3 MISSION

• Be a lowest cost zinc producer on a global scale, maintaining market leadership.

• One million tones zinc-lead metal capacity by 2010.

• Be innovative, customer oriented and eco-friendly, maximizing stake-holder value.

Refined zinc production capacity 669,000 tones per annum.

• Refined lead production capacity 85,000 tones per annum.

1.4 VISION -

Be a world-class zinc company, creating value, leveraging mineral resources ami related

coat competencies.

1.5 CERTIFICATE

Company is certified by three certificates.

• ISO 9001 For Quality Management System

• ISO 14001 For Environment Management

• OHSAS Occupational Health Safety Awareness Systems

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1.6 LOCATION OF HZL PLANT IN INDIA

Figure 1. Hindustan zinc on India map

1.7 DEPARTMENTATION

All the Departments of Zinc Smelter, Debari are categorized under the following heads.

1. PRODUCTION DEPARTMENT

Those departments which are directly engaged in the machine operation and

production of Zinc Ingot are known as production departments. The following departments are

categorized under this heading.

• Roaster and Acid Plant.

• Leaching, Purification and Cadmium Plant.

• Zinc Electrolysis and Melting Plant.

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2. SERVICE DEPARTMENTS:

The Departments, which are indirectly engaged in the production of Zinc Ingot by

providing some sort of, service to the production departments, they are categorized as under:-

• Personnel and Administration Department

• Industrial Engineering Celt

• Safety Department

• Stores Department

• Sales Department

• Account Department

3. SAFETY DEPARTMENT

In every production oriented organization one of the most important prerequisite is safety.

If in an organization safety precautions are overlooked, then it can sometimes cause serious

accidents, which lead to loss of mankind and ceases production activities. It looks after the safety

of the people working in the smelter and the factory. It keeps vigilance on the safety conditions

prevailing in the whole organization it provides all the necessary safety equipment to the

employees in the order to protect the employees from the acid and harmful gases. It is crucial

department.

S- (Sound) "thinking concerning the nature of the job"

A - (Alertness) "to danger"

F- (Factoring) "the entire operation into the safe requirement"

E-(Efficiency) "In carefully performing the work."

T- (Thoughtfulness) "For the welfare of the group in which the Workers is Attached"

Y - (You) "your own Protection and job".

4. STORE DEPARTMENT:

The main function of the stores department is to store and control all the items of inventory.

For this purpose there exists a proper coding system i.e. there is a separate code for inventory.

There are 11000 items in inventory. This deptt. Keeps check on the requirement of the varioks

materials.

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In brief it has the following functions:

• Procurement Of Materials

• Storage

• Issue Of Material

• Inventory Control

5. STORES RECORDS

As regards the documentation, right from the time when material is received to the time it

issued separate documents and vouchers are prepared.

• Receipt cum Inspection Report (RCIR)

• Stores Issue Voucher (SIB')

• Store Return Note (SRN)

6. SALES DEPARTMENT

All sales are affected through the central marketing office, New Delhi. The interested

parties contact at this office. The selling price of Zinc ingot is the monthly weighted average of the

price quoted by London Metal exchange. The credit policy is to offer 90 days credit to customer

purchasing more than 400 tones of Zinc ingot in a month and 60 days credit for a customer who

purchases less than 400 tones in a month. For ensuring the creditability of the customer, a letter of

credit is to be submitted by the customers at the CHO through this letter the customers bank takes

guarantee of prompt payment on behalf of the customers. The main function of accounts

department is to keep systematic records of all financial transactions. Accounts department is

further divided in different sections.

• Costing/ Budgeting Section

• Book-keeping Section

• Cash Section

• Contractor Bills Section

• Excise & Cen vat payment section

• Establishment Section

• Stores accounting and suppliers Bills Section

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7. COSTING/ BUDGETING SECTION:

The main function of the costing department is to prepare monthly and annual cost sheet,

which gives information regarding the cost of production, allocation and apportionment of cost.

The costing department is responsible for the annual cost audit of sulphuric acid (which is

statutory) costing section also prepares Revenue and Capital budgets, which are to be submitted to

the Head office latest by July every year.

8. BOOK KEEPING:

Book keeping section is mainly engaged in the preparation of Final account i.e. Profit and

loss account and Balance sheet. There exists a systematic coding system forIhe collection and

classification of data under various heads of income and expenditure.

9. STORE ACCOUNTING AND SUPPLIERS BILLS SECTION:

This section deals with the accounting of stores materials. Priced stores Lodge- is

maintained on the basis of weii4bted average method and proper record of SW, RC I R and SRN

are kept. This section gives accounting codes. Supplier's bills section passes the bills of all type of

supplies made by suppliers. Necessary advance, payment and other adjustments in accounting

books arc done in this section

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10. SAFETY

Figure 2. Safety tools

Safety is one of the fundamental needs of all living beings. Accident is an unwanted event

held due to carelessness. So precautions must be taken to avoid accidents.

There are two main reasons of accidents:

• Unwanted act

• Unwanted condition

In accidents occurred by unwanted acts, the worker is directly responsible. These occur due to lack

of concentration and over confidence of the worker. It can be minimized by maintaining

concentration and being patient while working.

The main reasons for accidents in form of unwanted acts are:

1. Use of machine or equipment without permission.

2. Loading material improperly.

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3. Oiling or greasing machines in running condition.

4. Standing in unsafe manner or condition.

5. Use of unsafe tool and lack of safety equipment.

6. Disobey the instructions and rules

.

Some unsafe conditions which motivate accidents are:

1. Work on grade less machine.

2. Presence of grease on floor.

3. Bad housekeeping and unsafe clothing.

4. Breaking or absence of railing on platform.

5. Leaking of gases.

There are many rules for safety but main golden rules are:

1. Follow all instructions and rules.

2. Correct or report unsafe conditions immediately.

3. Wear safety equipments whenever required.

4. Keep the workplace clean and tidy.

Workers working in the factory are exposed to all sorts of dangers, so they required themselves to

protect from these dangers. For these some personal protective equipment are available to protect

them from head to toe such as

1. Ear muff

2. Dust mask

3. Face shield

4. Gas mask

5. Gloves

6. Goggles

7. Helmets

8. Leg guard

9. Respirators

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10. Rubber apron

11. Rubber gumboots

12. Safety bell

13. Safety shoes

1.8 SOURCES OF RAW MATERIALS

1. ZAWAR GROUP OF MINES:

Zawar group of mines (Mochia, Balaria, Zawar Mala,& Baroi) is situated in the Girwa

Tehsil of Udaipur District of Rajasthan at a distance of about 35kms from Udaipur , amidst a

valley of Arawali hills.

2. RAJPURA-DARIBAMINES:

The multi-metal Rajpura Dariba Mines, which is located about 85km away from Udaipur

(Raj.)has demonstrated ore reserve of about 16.4 million tones having metal content of about

6.9%zinc& 2.2% lead.

3. MATON ROCK PHOSPHATE MINE (UDAIPUR) :

Maton mine has been developed to meet rock-phosphate requirements for the super-

phosphate &phosphoric acid plant at Debari.

4. RAMPURAAGUCHA MINING COMPLEX:

The prestigious Rampura Agucha Open Cast Mining Complex is Asia's richest & largest

lead – zinc deposit. It is situated in Tehsil Hurda, District Bhilwara in Rajasthan. The discovery of

a world class deposit of 60.6 million tones at Rampura Agucha, containing 15.4% metal has

dramatically altered the prospect of not only reducing the cost of production of zinc and lead, but

also the expansion of line’s production capacity resulting ita increasing the demand satisfaction up

to 82 %for zinc and 61% for lead.

1.9 ZINC PRODUCTION PROCESS 9

Figure 3. Zinc production process

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Table no. 3 zinc concentrate - typical analysis

Element Unit specification

Zn % 49-50

Pb % 4-4.5

fe % 8-10

Ag Ppm - 300

S % 31

Si02 % 1.5

1.10 ZINC PRODUCTION PLANT

1. Roasting plant

2. Leaching plant

3. Electrolysis plant

4. Effluent treatment plant

1. ROASTING PLANT

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Figure 4. Roster plant

In Roasting Plant. Oxidation of zinc sulfide concentrates at high temperatures into impure

Lille oxide. Called ‘Calcite". The chemical reactions taking place during t. process are:

2ZnS +302_______ 2ZnO + 2So2

2So2 + 02_______ 2So2

Approximately 90% of zinc in concentrates is oxidized to zinc oxide. But at the roasting

temperature around 10% of de zinc reacts with the iron impurities of the zinc sulfide concentrates

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to form zinc ferrite. A byproduct of roasting is sulfur dioxide. Which is further processed into

sulfuric acid. Zinc oxide obtained is then sent in leaching plant for further processing.

Firstly zinc sulphide after one concentration process is sent to furnace. There at 920-950 degree

temninture zinc sulfide combustion takes place producing calcine. Further oxidation of So2

maintains the temperature range. And then So3, sent to acid plant for production of sulphuric acid.

HZL Dariba has 2 roaster units R4 and R5. Zinc sulphide Concentrate is introduce directly into the

roaster and roasted in a turbulent layer. Largely consisting of roasted material especially Zinc

Oxide (ZnO). This layer has been heated to by ignition temperature by thee preheating device. The

desired reaction is maintained by an exothermic reaction of Sulfide Concentrate and air in the

turbulent layer.

The surplus reaction teat is taken out of the roaster bed by cooling element installed in the

turbulent layer in the form of evaporator heating surfaces connected to the. Waste Heat Boiler. The

waste heat is further utilized to generate electricity of about 9.6MW which is used in the plant.

Roaster part of plant also divided as follow:

I. Raw Material Handling (RMH)

2. Roaster

3. Was. Heat Reoovery Boihr (WHRB)

4. Hot Gas Precipitator (HGP)

5. Gas Cleaning Phit (GCP)

6. Sulphuric Acid Flint (SAP)

7. Acid Loading plant

1.1 ROASTER PLANT:-

At Debari, Zinc Smelter two roasters are used for roasting i.e. Roaster & Roaster2. Roasters are

mainly furnaces which are maintained at 950°C. These furnaces are fluidized type in which

fluidized bed is made and air is passed from bottom for oxidation. The fumaces are autogenously,

so only to start the reaction or to obtain required temperature of fuel is required.

1.2 ROASTER SPECIFICATION

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Table no.4 roster specification

Roaster 1 Roaster 2

Capacity 140 tonnes/day 240 tonnes/day

Health area 18.5 sqm 35 sqm

Air flow 9500 19500

Feed 5 tonnes 10 tonnes

No. of nozzle 1848 3500

Diameter 4.18 m 6.69 m

acid 100 m 200 m

2. LEACHING PLANT

The calcine is first leached in a neutral or slightly acidic solution (of sulphur. acid, in order

to leach the zinc out of zinc oxide. The remaining calcine is then leached in strong sulfuric acid to

leach the rest of the zinc out of the zinc oxide zinc ferrite. The result of this process is a solid and a

liquid

The liquid contain the zinc and is often called leach product. There is also iron in the leach

product from the strong acid leach. Which is removed in an intermediate step? In the form of

jarosite. Jarosite is a waste therefore is sent to Effluent treatment plant. There is still cadmium

copper, arsenic, antimony, cobalt, germanium and nickel in the leach product. Therefore it needs to

purify.

The basic leaching chemical formula that drives the process:

ZnO+ H2SO4______ ZnSO4 + H2O

MeO + H2SO4_____ MeSO4 + H20

Me—Metal other than Zinc present in concentration

Leaching Area is distributed in following buildings:

I. Weak acid leading building

2. Jerosite precipitation building

3. Purification building

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4. Gypsum removal building

Leaching of zinc concentrates is based on the oxidation of zinc sulfide in an acidic environment.

The reduction of ferric iron is accomplished by metal sulfides, which are leached:

MeS + Fe2(SO4)3 ______ MeSO4+ 2 FeSO4 + S

where Me = Zn, Fe, Cu, Co, Ni, Cd, Pb etc. Formed ferrous iron is oxidized by molecular oxygen

back to the ferric form:

2 FeSO4 + H2SO4 + 0.5 02_____ Fe2(SO4)3 + H2O

The reaction rate is catalyzed by copper. The overall reaction can be written as the following

simplified equation:

MeS + H2SO4 + 0.5 02 ______ MeSO4 + H2O + S

Zinc in the leach residues of neutral and weak acid leaching steps is mainly as zinc ferrites but also

small amount of unreacted zinc sulfide is present. Leaching of zinc ferrates can be described with

the following simplified equation:

ZnO•Fe203 + 4 H2SO4 —> ZnSO4 + Fe2(SO4)3 + 4 H2O

Ferrous iron is oxidized to ferric iron, which is precipitated as goethite:

2 FeSO4 + 3H20 + 0.5 02 —> 2FeO(OH) + 2 H2SO4

Neutralization of the formed sulfuric acid is made by zinc oxide:

2 H2SO4 + 2 ZnO — 2 ZnSO4 + 2 H20

The reaction system can be written as an overall reaction:

FeSO4 + ZnO + 0.5 H2O + 0.2502 ---> FeO(OH) + ZnSO4

3. ELECROLYSIS PLANT:

1. PURIFICATION:

Zinc sulfate so produced is separated from the remaining solid & passes to the next step,

which is purification. The purification process zinc dust & steam to remove copper, cadmium,

cobalt & nickel, which would interfere with electrolysis process.

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Purification is usually conducted in large agitated tanks. The process takes place at temperature

ranging from 40 to 85 °C (104 to 185 °F), and pressures ranging from .4 atm (240 kPa) (absolute

scale). The by-products are sold for further sulfate solution must be very pure for electro winning

to be at all efficient. Impurities can change the decomposition voltage enough to where the

electrolysis cell hydrogen gas rather than zinc metal.

2. ELECTROLYSIS:

Zinc is extracted from the purified zinc sulfate solution by electro winning, which is specified from

of electrolysis process. The process works by passing electric current through the solution in a

series of cells. This causes zinc to deposits on the cathode (aluminum sheet)) the anodes. Sulfuric

acid is also formed in the process & reused in the Every 24 to 48 hours each cell is shut down. Zinc

coated cathodes are remove & zinc is mechanically stripped from the aluminum plates. A portion

of electric energy is converted into heat, which increases the temperature of electrolyte. A portion

of electrolyte is continuously circulated through the cooling towers both to cool & concentrate

rough the evaporation of water. The cooled & concentrated electrolyte is he cells. The main

reaction can be represented as —

ZnSO4— Zn++ + SO4 –

S04 +H2O______ H2SO4 + ½ 02

4. EFFIUENT TREATMENT PLANT :

The effluent Plant can be divided into 5 sections :

1. Cadmium Removal

2. cyanide Destruction

3. fluoride Precipitation

4. heavy metals Removal

5. line slurry Make- up

1. CADMIUM REMOVAL:

The Cadmium plant produces the effluent containing 40% cadmium. Therefore this

Cadmium is precipitated before entering the main effluent treatment plant. The effluents are first

mixed with 10% w/w slurry & pH is maintained at 11.5. The solids are taken to a sludge tank,

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which also collects sludge from the main plant. The over flow from the thickener flows into the

primary reaction tank for the precipitation of the remaining heavy metals.

2. CYANIDE DESTRUCTION:

Blow down from the ISF gas washing system is received into an agitated tank, where the

pH is adjusted with a lime slurry. The pH is maintained at about 8. The effluent is pumped to a.

cascade tower prior to which the effluent is chlorinated with a vacuum ejector chlorine dosing

system, at a rate of 0.825 kg/hr. The cyanide decomposes during aeration in the cascade tower. the

effluent is then pumped to the treated effluent tank. The treated effluent is then pumped to the ISF

gas washing system at a rate of 10 gm cu. M/hr. The excess treated effluent is channeled to the

evaporation lagoons.

3. FLUORIDE PRECIPITATION:

Effluent from the gas cleaning plant is the main source of fluoride ion. In order to reduce

the level of fluoride to an acceptable level in final effluent this stream is treated with milk of lime

slurry to precipitate fluoride to 8 mg/l. The fluoride bearing stream is fed to agitated reaction tank

where it is mixed with milk of lime from the ring main & the pH controlled at approximately

neutral (pH 6-8). The resulting gypsum& calcium fluoride are filtered out on a plate & frame filter

pres. A standby press is provided. The coke is manually discharged &dumped. The filtrate is

pumped to the main effluent stream.

4. HEAVY METALS REMOVAL:

Effluent arising from the following sources is routed to either the primary or secondary

reaction tank

• Sinter plant (Blue Pow der Filtrate)

• Gas Cleaning Copper Recovery

• Water Treatment, Boiler

• Blow Down (Launder &Power Generation)

• Soft Water Circuit

In addition, intermittent wash-downs from the Acid Plant, Sinter Plant & Raw Material Handling

&Intermittent arising from the Precious Metal Plant. The reaction vessel also receives the cadmium

plant effluent & ISF gas washing effluent mentioned previously. The majority of heavy metals are 17

precipitated in two reaction tanks by treatment with lime slurry & continuous agitation at a pH of

8.0& 10.5 respectively in first &second tank. The effluent & precipitated solids are taken to a

30metre diameter thickener. The overflow from the thickener gravitates to the third reaction vessel

where the pH is adjusted to 9 by the addition of sulfuric acid (98%w/w). The underflow from the

thickener is pumped to sludge tank, which also receives cadmium sludge. This vessel is agitated to

maintain the solids in suspension. The liquor in the third reaction vessel precipitates gypsum as the

pH is lowered. This liquor is pumped for final clarification to a thickener where any solids

removed are pumped tothe sludge vessel mentioned above.The sludge collected in the sludge tank

is pumped as a slurry, to the Blue Powder Thickener where it is further thickened & returned to the

sinter plant.

5. LIME SLURRY MAKE-UP:

Lime of 80%Ca0 crude, received in 40 kg bags is transported by hand from the storage area

to the lime mixing tank at a rate about 1.1 tones/hr. The bags are split open on a grid over the

tank& mixed with treated recycled effluent water. The lime slurry is pumped via a transfer pump

to ahead tank, which supplies two sets of pumps feeding lime slurry (10% w/w) to the cadmium

plant & effluent treatment plant.

1.11 APPLICAT1ONS OF Zn, Pb AND PRINCIPAL BY PRODUCTS

The main uses of Zn are in galvanizing for protection of steel against corrosion, alloy

making (brass, bronze and bearing metals) dry cell batteries, die castings for automobiles parts,

business machines & toys.

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Figure 5. Uses of zinc

1. LEAD:

The main uses of lead are for storage batteries in transportation, ammunition, in defense,

lead protection for cables, chemical equipment, pigments &paints. Lead is also used in bearing&

soldering alloys, type metals, fusible alloys, in sound & vibration insulations, shield against X-ray

& nuclear radiations & as ballast weight.

2. CADMIUM:

Cadmium is used for pigments, electro-plating steel for improved corrosion resistance,

solders, brazing &bearing alloys, rechargeable batteries &nuclear control rods. It is also used for

plastic stabilizers and semiconductor materials.

3. SILVER:

The important industrial uses of silver are in photography, electrical switches, batteries,

stabilizers & in bearing alloys .Silver is extensively used for jewelry & coinage.

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4. TUNGSTEN:

Tungsten has become indispensable in strategic & industrial uses particularly in defense

armaments. It is mainly used in tungsten carbide tools, electrical bulbs &other electronic app.

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CHAPTER 2- PROJECT WORK

1. LATHE MACHINE

A lathe is a large class of lathes designed for precisely machining relatively hard materials.

They were originally designed to machine metals; however, with the advent of plastics and other

materials, and with their inherent versatility, they are used in a wide range of applications, and a

broad range of materials. In machining jargon, where the larger context is already understood, they

are usually simply called lathes, or else referred to by more-specific subtype names (toolroom

lathe, turret lathe, etc.). These rigid machine tools remove material from a rotating workpiece via

the (typically linear) movements of various cutting tools, such as tool bits and 

1.1 Lathe machine

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1. PARTS OF LATHE MACHINE

1. HEADSTOCK

1.2 Headstock with legend

The headstock (H1) houses the main spindle (H4), speed change mechanism (H2, H3),

and change gears (H10). The headstock is required to be made as robust as possible due to the

cutting forces involved, which can distort a lightly built housing, and induce harmonic vibrations

that will transfer through to the workpiece, reducing the quality of the finished workpiece.

2. BEDS

The bed is a robust base that connects to the headstock and permits the carriage and

tailstock to be moved parallel with the axis of the spindle. This is facilitated by hardened and

ground bed ways which restrain the carriage and tailstock in a set track. The carriage travels by

means of a rack and pinion system. The leadscrew of accurate pitch drives the carriage holding the

cutting tool via a gearbox driven from the headstock.

Types of beds include inverted "V" beds, flat beds, and combination "V" and flat beds. "V" and

combination beds are used for precision and light duty work, while flat beds are used for heavy

duty work.

When a lathe is installed, the first step is to level it, which refers to making sure the bed is not

twisted or bowed. There is no need to make the machine exactly horizontal, but it must be entirely

untwisted to achieve accurate cutting geometry. A precision level is a useful tool for identifying

and removing any twist. It is advisable also to use such a level along the bed to detect bending, in

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the case of a lathe with more than four mounting points. In both instances the level is used as a

comparator rather than an absolute reference.

3. FEED AND LEAD SCREWS

The feed screw (H8) is a long driveshaft that allows a series of gears to drive the carriage

mechanisms. These gears are located in the apron of the carriage. Both the feed screw

and leadscrew (H7) are driven by either the change gears (on the quadrant) or an intermediate

gearbox known as a quick change gearbox (H6) or Norton gearbox. These intermediate gears

allow the correct ratio and direction to be set for cutting threads or worm gears. Tumbler gears

(operated by H5) are provided between the spindle and gear train along with a quadrant plate that

enables a gear train of the correct ratio and direction to be introduced. This provides a constant

relationship between the numbers of turns the spindle makes, to the number of turns the leadscrew

makes. This ratio allows screw threads to be cut on the workpiece without the aid of a die.

Some lathes have only one leadscrew that serves all carriage-moving purposes. For screw cutting,

a half nut is engaged to be driven by the leadscrew's thread; and for general power feed, a key

engages with a keyway cut into the leadscrew to drive a pinion along a rack that is mounted along

the lathe bed.

The precise ratio required to convert a lathe with an Imperial (inch) leadscrew to metric

(millimeter) threading is 100 / 127 = 0.7874... . The best approximation with the fewest total teeth

is very often 37 / 47 = 0.7872... . This transposition gives a constant -0.020 percent error over all

customary and model-maker's metric pitches (0.25, 0.30, 0.35, 0.40, 0.45, 0.50, 0.60, 0.70, 0.75,

0.80, 1.00, 1.25, 1.50, 1.75, 2.00, 2.50, 3.00, 3.50, 4.00, 4.50, 5.00, 5.50 and 6.00 mm).

4. CARRIAGE

In its simplest form the carriage holds the tool bit and moves it longitudinally (turning) or

perpendicularly (facing) under the control of the operator. The operator moves the carriage

manually via the hand wheel (5a) or automatically by engaging the feed shaft with the carriage

feed mechanism (5c). This provides some relief for the operator as the movement of the carriage

becomes power assisted. The hand wheels (2a, 3b, 5a) on the carriage and its related slides are

usually calibrated both for ease of use and to assist in making reproducible cuts. Calibration marks

will measure either the distance from center (radius), or the work piece's diameter, so for example,

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on a diameter machine where calibration marks are in thousandths of an inch, the radial hand

wheel dial will read .0005 inches of radius per division, or .001 inches of diameter. The carriage

typically comprises a top casting, known as the saddle (4), and a side casting, known as the apron

5. CROSS-SLIDE

The cross-slide (3) rides on the carriage and has a feed screw that travels at right angles to

the main spindle axis. This permits facing operations to be performed, and the depth of cut to be

adjusted. This feed screw can be engaged, through a gear train, to the feed shaft (mentioned

previously) to provide automated 'power feed' movement to the cross-slide. On most lathes, only

one direction can be engaged at a time as an interlock mechanism will shut out the second gear

train.

6. COMPOUND REST

The compound rest (or top slide) (2) is usually where the tool post is mounted. It provides

a smaller amount of movement (less than the cross-slide) along its axis via another feed screw. The

compound rest axis can be adjusted independently of the carriage or cross-slide. It is used for

turning tapers, to control depth of cut when screw cuts or precision facing, or to obtain finer feeds

(under manual control) than the feed shaft permits. Usually, the compound rest has a protractor

marked in its base (2b), enabling the operator to adjust its axis to precise angles.

The slide rest (as the earliest forms of carriage were known) can be traced to the fifteenth century.

In 1718 the tool-supporting slide rest with a set of gears was introduced by a Russian

inventor Andrey Natron and had limited usage in the Russian industry.[1] In the eighteenth century

the slide rest was also used on French ornamental turning lathes. The suite of gun boring mills at

the Royal Arsenal, Woolwich, in the 1780s by the Verbruggan family also had slide rests.

.

7. TOOL POST

The tool bit is mounted in the tool post (1) which may be of the American lantern style,

traditional four-sided square style, or a quick-change style such as the multibit arrangement

pictured. The advantage of a quick change set-up is to allow an unlimited number of tools to be

used (up to the number of holders available) rather than being limited to one tool with the lantern

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style, or to four tools with the four-sided type. Interchangeable tool holders allow all tools to be

preset to a center height that does not change, even if the holder is removed from the machine

.

8. TAILSTOCK

1.3 Tailstock

The tailstock is a tool (drill), and center mount, opposite the headstock. The

spindle (T5) does not rotate but does travel longitudinally under the action of a leadscrew and hand

wheel (T1). The spindle includes a taper to hold drill bits, centers and other tooling. The tailstock

can be positioned along the bed and clamped (T6) in position as dictated by the work piece. There

is also provision to offset the tailstock (T4) from the spindles axis, this is useful for turning small

tapers, and when re-aligning the tailstock to the axis of the bed.

The image shows a reduction gear box (T2) between the hand wheel and spindle, where large drills

may necessitate the extra leverage. The tool bit is normally made of HSS, cobalt steel or carbide.

9. STEADY, FOLLOWER AND OTHER RESTS

1.4 Steady rest

25

Long workpieces often need to be supported in the middle, as cutting tools can push (bend)

the work piece away from where the centers can support them, because cutting metal produces

tremendous forces that tend to vibrate or even bend the workpiece. This extra support can be

provided by a steady rest (also called a steady, a fixed steady, a center rest, or sometimes,

confusingly, a center). It stands stationary from a rigid mounting on the bed, and it supports the

workpiece at the rest's center, typically with three contact points 120° apart. A follower rest (also

called a follower or a travelling steady) is similar, but it is mounted to the carriage rather than the

bed, which means that as the tool bit moves, the follower rest "follows along" (because they are

both rigidly connected to the same moving carriage).[2] [3] Follower rests can provide support that

directly counteracts the springing force of the tool bit, right at the region of the workpiece being

cut at any moment. In this respect they are analogous to a box tool.

Any rest transfers some workpiece geometry errors from base (bearing surface) to processing

surface. It depends on the rest design. For minimum transfer rate correcting rests are used.

Rest rollers typically cause some additional geometry errors on processing surface.

2. TYPES OF LATHE MACHINE

1. CENTER LATHE / ENGINE LATHE / BENCH LATHE

1.5 A typical center lathe

Engine lathe is the name applied to a traditional late-19th-century or 20th-century lathe

with automatic feed to the cutting tool, as opposed to early lathes which were used with hand-held

tools, or lathes with manual feed only. The usage of "engine" here is in the mechanical-device 26

sense, not the prime-mover sense, as in the steam engines which were the standard industrial

power source for many years. The works would have one large steam engine which would provide

power to all the machines via a line shaft system of belts. Therefore early engine lathes were

generally 'cone heads', in that the spindle usually had attached to it a multi-step pulley called

a cone pulley designed to accept a flat belt. Different spindle speeds could be obtained by moving

the flat belt to different steps on the cone pulley. Cone-head lathes usually had a countershaft ( lay

shaft) on the back side of the cone which could be engaged to provide a lower set of speeds than

was obtainable by direct belt drive. These gears were called back gears. Larger lathes sometimes

had two-speed back gears which could be shifted to provide a still lower set of speeds.

When electric motors started to become common in the early 20th century, many cone-head lathes

were converted to electric power. At the same time the state of the art in gear and bearing practice

was advancing to the point that manufacturers began to make fully geared headstocks, using

gearboxes analogous to automobile transmissions to obtain various spindle speeds and feed rates

while transmitting the higher amounts of power needed to take full advantage of high speed

steel tools. Cutting tools evolved once again, with the introduction of manmade carbides, and

2. TOOL ROOM LATHE

1.6 Tool room lathe

A tool room lathe is a lathe optimized for tool room work. It is essentially just a top-of-the-

line center lathe, with all of the best optional features that may be omitted from less expensive

27

models, such as a collet closer, taper attachment, and others. The bed of a tool room lathe is

generally wider than that of a standard center lathe. There has also been an implication over the

years of selective assembly and extra fitting, with every care taken in the building of a tool room

model to make it the smoothest-running, most-accurate version of the machine that can be built.

However, within one brand, the quality difference between a regular model and its corresponding

tool room model depends on the builder and in some cases has been partly marketing psychology.

For name-brand machine tool builders who made only high-quality tools, there wasn't necessarily

any lack of quality in the base-model product for the "luxury model" to improve upon. In other

cases, especially when comparing different brands, the quality differential between (1) an entry-

level center lathe built to compete on price, and (2) a tool room lathe meant to compete only on

quality and not on price, can be objectively demonstrated by measuring TIR, vibration, etc. In any

case, because of their fully ticked-off option list and (real or implied) higher quality, tool room

lathes are more expensive than entry-level center lathes

.

3. TURRET LATHE AND CAPSTAN LATHE

1.7 Turret lathe

Turret lathes and capstan lathes are members of a class of lathes that are used for repetitive

production of duplicate parts (which by the nature of their cutting process are

usually interchangeable). It evolved from earlier lathes with the addition of the turret, which is

an index able tool holder that allows multiple cutting operations to be performed, each with a

28

different cutting tool, in easy, rapid succession, with no need for the operator to perform setup

tasks in between (such as installing or uninstalling tools) nor to control the toolpath. (The latter is

due to the toolpath's being controlled by the machine, either in jig-like fashion [via the mechanical

limits placed on it by the turret's slide and stops] or visit-directed servomechanisms [on computer

numerical controlled (CNC) lathes].)[4]

There is a tremendous variety of turret lathe and capstan lathe designs, reflecting the variety of

work that they do.

4. GANG-TOOL LATHE

A gang-tool lathe is one that has a row of tools set up on its cross-slide, which is long and

flat and is similar to a milling machine table. The idea is essentially the same as with turret lathes:

to set up multiple tools and then easily index between them for each part-cutting cycle. Instead of

being rotary like a turret, the index able tool group is linear.

5. MULTI SPINDLE LATHE

1.8 Multi spindle lathes

29

Multi spindle lathes have more than one spindle and automated control (whether

via cams or CNC). They are production machines specializing in high-volume production. The

smaller types are usually called screw machines, while the larger variants are usually

called automatic chucking machines, automatic chuckers, or simply chuckers. Screw machines

usually work from bar stock, while checkers automatically chuck up individual blanks from

agazine. Typical minimum profitable production lot size on a screw machine is in the thousands of

parts due to the large setup time. Once set up, a screw machine can rapidly and efficiently produce

thousands of parts on a continuous basis with high accuracy, low cycle time, and very little human

intervention. (The latter two points drive down the unit cost per interchangeable part much lower

than could be achieved without these machines.)

6. CNC LATHE / CNC TURNING CENTER

1.9 CNC lathe with milling capabilities

30

Computer numerical controlled (CNC) lathes are rapidly replacing the older production

lathes (multi spindle, etc.) due to their ease of setting, operation, repeatability and accuracy. They

are designed to use modern carbide tooling and fully use modern processes. The part may be

designed and the tool paths programmed by the CAD/CAM process or manually by the

programmer, and the resulting file uploaded to the machine, and once set and trailed the machine

will continue to turn out parts under the occasional supervision of an operator.

The machine is controlled electronically via a computer menu style interface; the program may be

modified and displayed at the machine, along with a simulated view of the process. The

setter/operator needs a high level of skill to perform the process, however the knowledge base is

broader compared to the older production machines where intimate knowledge of each machine

was considered essential. These machines are often set and operated by the same person, where the

operator will supervise a small number of machines (cell).

7. SWISS-STYLE LATHE / SWISS TURNING CENTER 

1.10 A view inside the enclosure of a CNC Swiss-style lathe/screw machine

31

A Swiss-style lathe is a specific design of lathe providing extreme accuracy (sometimes

holding tolerances as small as a few tenths of a thousandth of an inch—a few micrometers). A

Swiss-style lathe holds the workpiece with both a collet and a guide bushing. The collet sits behind

the guide bushing, and the tools sit in front of the guide bushing, holding stationary on the Z axis.

To cut lengthwise along the part, the tools will move in and the material itself will move back and

forth along the Z axis. This allows all the work to be done on the material near the guide bushing

where it is more rigid, making them ideal for working on slender workpieces as the part is held

firmly with little chance of deflection or vibration occurring. This style of lathe is commonly used

under CNC control.

Most CNC Swiss-style lathes today use one or two main spindles plus one or two back spindles

(secondary spindles). The main spindle is used with the guide bushing for the main machining

operations.

8. COMBINATION LATHE / 3-IN-1 MACHINE

1.11 combination lathe, often known as a 3-in-1 machine

32

Introduces drilling or milling operations into the design of the lathe. These machines have

a milling column rising up above the lathe bed, and they utilize the carriage and topside as the X

and Y axes for the milling column. The 3-in-1 name comes from the idea of having a lathe, milling

machine, and drill press all in one affordable machine tool. These are exclusive to the hobbyist

and MRO markets, as they inevitably involve compromises in size, features, rigidity, and precision

in order to remain affordable. Nevertheless, they meet the demand of their niche quite well, and are

capable of high accuracy given enough time and skill. They may be found in smaller, non-

machine-oriented businesses where the occasional small part must be machined, especially where

the exacting tolerances of expensive tool room machines, besides being unaffordable, would be

overkill for the application from an engineering perspective.

9. MINI-LATHE AND MICRO-LATHE

1.12 Mini-lathe

Mini-lathes and micro-lathes are miniature versions of a general-purpose center lathe

(engine lathe). They typically have swings in the range of 3 to 7 in (76 to 178 mm) diameter (in

other words, 1.5 to 3.5 in (38 to 89 mm) radius). They are small and affordable lathes for the home

workshop or MRO shop. The same advantages and disadvantages apply to these machines as

explained earlier regarding 3-in-1 machines.

33

As found elsewhere in English-language orthography, there is variation in the styling of the

prefixes in these machines' names. They are alternately styled as mini lathe, minilathe, and mini-

lathe and as micro lathe, micro lathe, and micro-lathe

.

10. WHEEL LATHE

A lathe for turning the wheels of railway locomotives and rolling stock [5]

11. PIT LATHE

A lathe for large diameter, though short work, built over a recess in the floor to admit the

lower part of the workpiece thus allowing the tool rest to stand at the turner's waist height. An

example is on display at the London Science Museum, Kensington.

12. BRAKE LATHE

A lathe specialized for the task of resurfacing brake drums and discs in automotive or truck

garages.

13. OIL COUNTRY LATHE

Specialized lathes for machining long workpieces such as segments of drill strings. Oil

country lathes are equipped with large-bore hollow spindles, a second chuck on the opposite side

of the headstock, and frequently outboard steadies for supporting long workpieces.

3. APPLICATION OF LATHE MACHINE

A lathe is a machine tool which rotates the workpiece on its axis to perform various

operations such as

1 Cutting

2 Sanding

3 Knurling

3 Drilling

4 Deformations

5 Faci

34

2. DRIL PRESS MACHINE

A drill is a tool fitted with a cutting tool attachment or driving tool attachment, usually

a drill bit or driver bit, used for boring holes in various materials or fastening various materials

together with the use of fasteners. The attachment is gripped by a chuck at one end of the drill and

rotated while pressed against the target material. The tip, and sometimes edges, of the cutting tool

does the work of cutting into the target material. This may be slicing off thin shavings (twist

drills or auger bits), grinding off small particles (oil drilling), crushing and removing pieces of the

workpiece (SDS masonry drill), countersinking, counter boring, or other operations.

Drills are commonly used in woodworking, metalworking, construction and do-it-

yourself projects. Specially designed drills are also used in medicine, space missions and other

applications. Drills are available with a wide variety of performance characteristics, such

as power and capacity.

2.1 dril press machine

35

1. TYPES OF DRILL MACHINE

There are many types of drills: some are powered manually, others use electricity (electric

drill) or compressed air (pneumatic drill) as the motive power and a minority is driven by

an internal combustion engine (for example, earth drilling augers). Drills with a percussive action

(hammer drills) are mostly used in hard materials such as masonry (brick, concrete and stone)

or rock. Drilling rigs are used to bore holes in the earth to obtain water or oil. Oil wells,  water

wells, or holes for geothermal heating are created with large drilling rigs. Some types of hand-held

drills are also used to drive screws and other fasteners. Some small appliances that have no motor

of their own may be drill-powered, such as small pumps, grinders, etc.

1. HAND DRILLS

A variety of hand-powered drills have been employed over the centuries. Here are a few,

starting with approximately the oldest:

Bow drill

Brace and bit

Gimlet

Hand drill, also known as an "eggbeater" drill

Breast drill, similar to an "eggbeater" drill, it has a flat chest piece instead of a handle

Push drill, a tool using a spiral ratchet mechanism

Pin chuck, a small hand-held jeweler's drill

2.2 Hand drills

36

An old hand drill or "eggbeater" drill. The hollow wooden handle, with screw-on cap, is used to

store drill bits

2. PISTOL-GRIP (CORDED) DRILL

2.3 Anatomy of a pistol-grip corded drill.

Drills with pistol grips are the most common type in use today, and are available in a huge

variety of subtypes. A less common type is the right-angle drill, a special tool used by tradesmen

such as plumbers and electricians. The motor used in corded drills is often a universal motor due to

its high power to weight ratio.

For much of the 20th century, many attachments could commonly be purchased to convert corded

electric hand drills into a range of other power tools, such as orbital sanders and power saws, more

cheaply than purchasing conventional, self-contained versions of those tools (the greatest saving

being the lack of an additional electric motor for each device). As the prices of power tools and

suitable electric motors have fallen, however, such attachments have become much less common.

A similar practice is currently employed for cordless tools where the battery, the most expensive

component, is shared between various motorized devices, as opposed to a single electric motor

being shared between mechanical attachments.

37

3. HAMMER DRILL

The hammer drill is similar to a standard electric drill, with the exception that it is

provided with a hammer action for drilling masonry. The hammer action may be engaged or

disengaged as required. Most electric hammer drills are rated (input power) at between 600 and

1100 watts. The efficiency is usually 50-60% i.e. 1000 watts of input is converted into 500-600

watts of output (rotation of the drill and hammering action).

The hammer action is provided by two cam plates that make the chuck rapidly pulse forward and

backward as the drill spins on its axis. This pulsing (hammering) action is measured in Blows per

Minute (BPM) with 10,000 or more BPMs being common. Because the combined mass of the

chuck and bit is comparable to that of the body of the drill, the energy transfer is inefficient and

can sometimes make it difficult for larger bits to penetrate harder materials such as poured

concrete. The operator experiences considerable vibration and the cams are generally made from

hardened steel to avoid them wearing out quickly. In practice, drills are restricted to standard

masonry bits up to 13 mm (1/2 inch) in diameter. A typical application for a hammer drill is

installing electrical boxes, conduit straps or shelves in concrete.

4. ROTARY HAMMER DRILL

2.4 A rotary hammer drill

The rotary hammer drill (also known as a rotary hammer, roto hammer drill or masonry

drill) combines a primary dedicated hammer mechanism with a separate rotation mechanism, and

38

is used for more substantial material such as masonry or concrete. Generally, standard chucks and

drills are inadequate and chucks such as SDS and carbide drills that have been designed to

withstand the percussive forces are used. Some styles of this tool are intended for masonry drilling

only and the hammer action cannot be disengaged. Other styles allow the drill to be used without

the hammer action for normal drilling, or hammering to be used without rotation for chiseli

5. CORDLESS DRILLS

2.5 Cordless drill

A cordless drill is an electric drill which uses rechargeable batteries. These drills are available with

similar features to an AC mains-powered drill. They are available in the hammer drill

configuration and most have a clutch, which aids in driving screws into various substrates while

not damaging them. Also available are right angle drills, which allow a worker to drive screws in a

tight space. While 21st century battery innovations allow significantly more drilling, large

diameter holes (typically 12–25 mm (0.5–1.0 in) or larger) may drain current cordless drills

quickly.

39

For continuous use, a worker will have one or more spare battery packs charging while drilling,

and quickly swap them instead of having to wait an hour or more for recharging, although there are

now Rapid Charge Batteries that can charge in 10–15 minutes.

Early cordless drills used interchangeable 7.2 V battery packs. Over the years battery voltages have

increased, with 18 V drills being most common, but higher voltages are available, such as 24 V,

28 V, and 36 V. This allows these tools to produce as much torque as some corded drills.

6. DRILL PRESS

2.6 A drill press

drill press (also known as a pedestal drill, pillar drill, or bench drill) is a fixed style of drill

that may be mounted on a stand or bolted to the floor or workbench. Portable models with

a magnetic base grip the steel workpieces they drill. A drill press consists of a base, column (or

pillar), table, spindle (or quill), and drill head, usually driven by an induction motor. The head has

a set of handles (usually 3) radiating from a central hub that, when turned, move the spindle and

chuck vertically, parallel to the axis of the column.

A drill press has a number of advantages over a hand-held drill:

Less effort is required to apply the drill to the workpiece. The movement of the chuck and

spindle is by a lever working on a rack and pinion, which gives the operator

considerable mechanical advantage

40

The table allows a vise or clamp to be used to position and restrain the work, making the

operation much more secure

The angle of the spindle is fixed relative to the table, allowing holes to be drilled accurately

and consistently

Drill presses are almost always equipped with more powerful motors compared to hand-held

Drill presses are often used for miscellaneous workshop tasks other than drilling holes. This

includes sanding, honing, and polishing.

7. GEARED HEAD DRILL PRESS

2.8 Geared head drill press.

A geared head drill press is a drill press in which power transmission from the motor to the

spindle is achieved solely through spur gearing inside the machine's head. No friction elements

(e.g., belts) of any kind are used, which assures a positive drive at all times and minimizes

41

maintenance requirements. Gear head drills are intended for metalworking applications where the

drilling forces are higher and the desired speed (RPM) is lower than that used for woodworking.

Levers attached to one side of the head are used to select different gear ratios to change the spindle

speed, usually in conjunction with a two- or three-speed motor (this varies with the material). Most

machines of this type are designed to be operated on three-phase electric power and are generally

of more rugged construction than equivalently sized belt-driven units. Virtually all examples have

geared racks for adjusting the table and head position on the column.

perform tapping operations without the need for an external tapping attachment. This feature is

commonplace on larger gear head drill presses. A clutch mechanism drives the tap into the part

under power and then backs it out of the threaded hole once the proper depth is reached. Coolant

systems are also common on these machines to prolong tool life under production conditions.

A radial arm drill press is a large geared head drill press in which the head can be moved along an

arm that radiates from the machine's column. As it is possible to swing the arm relative to the

machine's base, a radial arm drill press is able to operate over a large area without having to

reposition the workpiece. This saves considerable time because it is much faster to reposition the

drill head than it is to unclamp, move, and then re-clamp the workpiece to the table. The size of

work that can be handled may be considerable, as the arm can swing out of the way of the table,

allowing an overhead or derrick to place a bulky workpiece on the table or base. A vise may be

used with a radial arm drill press, but more often the workpiece is secured directly to the table or

base, or is held in a fixture.

8. MILL DRILL

Mill drills are a lighter alternative to a milling machine. They combine a drill press (belt

driven) with the X/Y coordinate abilities of the milling machine's table and a locking collet that

ensures that the cutting tool will not fall from the spindle when lateral forces are experienced

against the bit. Although they are light in construction, they have the advantages of being space-

saving and versatile as well as inexpensive; being suitable for light machining that may otherwise

not be affordable

42

3. SHAPER MACHINE

3.1 shaper

A shaper is a type of machine tool that uses linear relative motion between the workpiece

and a single-point cutting tool to machine a linear toolpath. Its cut is analogous to that of a lathe,

except that it is (archetypally) linear instead of helical. (Adding axes of motion can yield helical

toolpaths, has also done in helical planning.) A shaper is analogous to a player, but smaller, and

with the cutter riding a ram that moves above a stationary workpiece, rather than the entire

workpiece moving beneath the cutter. The ram is moved back and forth typically by a crank inside

the column; hydraulically actuated shapers also exist.

1. TYPES

Shapers are mainly classified as

1 standard

2 draw-cut

3 horizontal

4 Universal

5 Vertical43

6 Geared

7 Cranks

8 Hydraulic

9 Contours

10 traveling head

The horizontal arrangement is the most common. Vertical shapers are generally fitted with

a rotary table to enable curved surfaces to be machined (same idea as in helical planning). The

vertical shaper is essentially the same thing as a slitter (slotting machine), although technically a

distinction can be made if one defines a true vertical shaper as a machine whose slide can be

moved from the vertical. A slitter is fixed in the vertical plane.

Small shapers have been successfully made to operate by hand power. As size increases, the mass

of the machine and its power requirements increase, and it becomes necessary to use a motor or

other supply of mechanical power. This motor drives a mechanical arrangement (using a pinion

gear, bull gear, and crank, or a chain over sprockets) or a hydraulic motor that supplies the

necessary movement via hydraulic cylinders.

2. OPERATION

3.2 Shaper linkage

The workpiece mounts on a rigid, box-shaped table in front of the machine. The height of

the table can be adjusted to suit this workpiece, and the table can traverse sideways underneath the

reciprocating tool, which is mounted on the ram. Table motion may be controlled manually, but is

44

usually advanced by automatic feed mechanism acting on the feed screw. The ram slides back and

forth above the work. At the front end of the ram is a vertical tool slide that may be adjusted to

either side of the vertical plane along the stroke axis. This tool-slide holds the clapper box and tool

post, from which the tool can be positioned to cut a straight, flat surface on the top of the

workpiece. The tool-slide permits feeding the tool downwards to deepen a cut. This adjustability,

coupled with the use of specialized cutters and tool holders, enable the operator to cut internal and

external gear tooth profiles, splines, dovetails, and keyways.

The ram is adjustable for stroke and, due to the geometry of the linkage, it moves faster on the

return (non-cutting) stroke than on the forward, cutting stroke. This action is via a slotted

link or Whitworth link.

3.APLICATION OF SHAPER MACHINE

The most common use is to machine straight, flat surfaces, but with ingenuity and some

accessories a wide range of work can be done. Other examples of its use are:

Keyways in the boss of a pulley or gear can be machined without resorting to a

dedicated broaching setup.

Dovetail slides

Internal splines and gear teeth.

Keyway, spline, and gear tooth cutting in blind holes

Cam drums with toolpaths of the type that in CNC milling terms would require 4- or 5-axis

contouring or turn-mill cylindrical interpolation

It is even possible to obviate wire EDM work in some cases. Starting from a drilled or cored

hole, a shaper with a boring-bar type tool can cut internal features that don't lend themselves to

milling or boring (such as irregularly shaped holes with tight corners).

45

4. PLANER

4.1 planer

A planer is a type of metalworking machine tool that uses linear relative motion between the

workpiece and a single-point cutting tool to machine a linear toolpath.[1] Its cut is analogous to that

of a lathe, except that it is (archetypally) linear instead of helical. (Adding axes of motion can yield

helical toolpaths; see "Helical planing" below.) A planer is analogous to a shaper, but larger, and

with the entire workpiece moving on a table beneath the cutter, instead of the cutter riding a ram

that moves above a stationary workpiece. The table is moved back and forth on the bed beneath the

cutting head either by mechanical means, such as a rack and pinion drive or a leadscrew, or by

a hydraulic cylinder.

1. TYPES OF PLANNER

1. LINEAR PLANING

The most common applications of planers and shapers are linear-toolpath ones, such as:

Generating accurate flat surfaces. (While not as precise as grinding, a planer can remove a

tremendous amount of material in one pass with high accuracy.)[1]

Cutting slots (such as keyways).

46

It is even possible to obviate wire EDM work in some cases. Starting from a drilled or cored

hole, a planer with a boring-bar type tool can cut internal features that don't lend themselves to

milling or boring (such as irregularly shaped holes with tight corners).

2. HELICAL PLANNING

Although the archetypal toolpath of a planer is linear, helical toolpaths can be

accomplished via features that correlate the tool's linear advancement to simultaneous workpiece

rotation (for example, an indexing head with linkage to the main motion of the planer). To use

today's terminology, one can give the machine other axes in addition to the main axis. The helical

planing idea shares close analogy with both helical milling and single-point screw cutting.

Although this capability existed from almost the very beginning of planers (circa 1820),[2] the

machining of helical features (other than screw threads themselves) remained a hand-filing affair

in most machine shops until the 1860s, and such hand-filing did not become rare until another

several decades had passed.

2. APPLICATION OF PLANER

Planers and shapers are now obsolescent, because other machine tools (such as milling

machines, broaching machines, and grinding machines) have mostly eclipsed them as the tools of

choice for doing such work. However, they have not yet disappeared from the metalworking

world. Planers are used by smaller tool and die shops within larger production facilities to maintain

and repair large stamping dies and plastic injection molds. Additional uses include any other task

where an abnormally large (usually in the range of 4'×8' or more) block of metal must be squared

when a (quite massive) horizontal grinder or floor mill is unavailable, too expensive, or otherwise

impractical in a given situation. As usual in the selection of machine tools, an old machine that is

in hand, still works, and is long since paid-for has substantial cost advantage over a newer machine

that would need to be purchased. This principle easily explains why "old-fashioned" techniques

often have a long period of gradual obsolescence in industrial contexts, rather than a sharp drop-off

of prevalence such as is seen in mass-consumer technology fashions.

47

5. MILLING MACHINE

Milling is the machining process of using rotary cutters to remove material[1] from a

workpiece advancing (or feeding) in a direction at an angle with the axis of the tool.[2][3] It covers a

wide variety of different operations and machines, on scales from small individual parts to large,

heavy-duty gang milling operations. It is one of the most commonly used processes in industry and

machine shops today for machining parts to precise sizes and shapes.

Milling can be done with a wide range of machine tools. The original class of machine tools for

milling was the milling machine (often called a mill). After the advent of computer numerical

control (CNC), milling machines evolved into machining centers (milling machines with

automatic tool changers, tool magazines or carousels, CNC control, coolant systems, and

enclosures), generally classified as vertical machining centers (VMCs) and horizontal

machining centers (HMCs). The integration of milling into turning environments and of turning

into milling environments, begun with live tooling for lathes and the occasional use of mills for

turning operations, led to a new class of machine tools,multi-tasking machines (MTMs), which

are purpose-built to provide for a default machining strategy of using any combination of milling

and turning within the same work envelope.

5.1 milling machine

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1. TOOLING

The accessories and cutting tools used on machine tools (including milling machines) are

referred to in aggregate by the noun “tooling". There is a high degree of standardization of the

tooling used with CNC milling machines, and a lesser degree with manual milling machines. To

ease up the organization of the tooling in CNC production many companies use a tool

management solution. Milling cutters for specific applications are held in various tooling

configurations. NC milling machines nearly always use SK (or ISO), CAT, BT or HSK tooling.

SK tooling is the most common in Europe, while CAT tooling, sometimes called V-Flange

Tooling, is the oldest and probably most common type in the USA. CAT tooling was invented by

Caterpillar of Peoria, Illinois, in order to standardize the tooling used on their machinery. CAT

tooling comes in a range of sizes designated as CAT-30, CAT-40, CAT-50, etc. The number refers

to the Association for Manufacturing Technology (formerly the National Machine Tool Builders

Association (NMTB)) Taper size of the tool.

5.2 Milling tools

An improvement on CAT Tooling is BT Tooling, which looks similar and can easily be confused

with CAT tooling. Like CAT Tooling, BT Tooling comes in a range of sizes and uses the same

NMTB body taper. However, BT tooling is symmetrical about the spindle axis, which CAT tooling

is not. This gives BT tooling greater stability and balance at high speeds. One other subtle

difference between these two tool holders is the thread used to hold the pull stud. CAT Tooling is

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all Imperial thread and BT Tooling is all Metric thread. Note that this affects the pull stud only, it

does not affect the tool that they can hold, both types of tooling are sold to accept both Imperial

and metric sized tools.

SK and HSK tooling, sometimes called "Hollow Shank Tooling", is much more common in

Europe where it was invented than it is in the United States. It is claimed that HSK tooling is even

better than BT Tooling at high speeds. The holding mechanism for HSK tooling is placed within

the (hollow) body of the tool and, as spindle speed increases, it expands, gripping the tool more

tightly with increasing spindle speed. There is no pull stud with this type of tooling.

For manual milling machines, there is less standardization, because a greater plurality of formerly

competing standards exists. Newer and larger manual machines usually use NMTB tooling. This

tooling is somewhat similar to CAT tooling but requires a drawbar within the milling machine.

Furthermore, there are a number of variations with NMTB tooling that make interchangeability

troublesome. The older a machine, the greater the plurality of standards that may apply

(e.g., Morse, Jaron, Brown & Sharpe, Van Norman, and other less common builder-specific

tapers). However, two standards that have seen especially wide usage are the Morse #2 and the R8,

whose prevalence was driven by the popularity of the mills built by Bridgeport

Machines of Bridgeport, Connecticut. These mills so dominated the market for such a long time

that "Bridgeport" is virtually synonymous with "manual milling machine". Most of the machines

that Bridgeport made between 1938 and 1965 used a Morse taper #2, and from about 1965 onward

most used an R8 taper.

2. PROCESS

5.3 Face milling process

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Milling is a cutting process that uses a milling cutter to remove material from the surface of

a workpiece. The milling cutter is a rotary cutting, often with multiple cutting points. As opposed

to drilling, where the tool is advanced along its rotation axis, the cutter in milling is usually moved

perpendicular to its axis so that cutting occurs on the circumference of the cutter. As the milling

cutter enters the workpiece, the cutting edges (flutes or teeth) of the tool repeatedly cut into and

exit from the material, shaving off chips (swarf) from the workpiece with each pass. The cutting

action is shear deformation; material is pushed off the workpiece in tiny clumps that hang together

to a greater or lesser extent (depending on the material) to form chips. This makes metal cutting

somewhat different (in its mechanics) from slicing softer materials with a blade.

The milling process removes material by performing many separate, small cuts. This is

accomplished by using a cutter with many teeth, spinning the cutter at high speed, or advancing the

material through the cutter slowly; most often it is some combination of these three approaches.[2] The speeds and feeds used are varied to suit a combination of variables. The speed at which the

piece advances through the cutter is called feed rate, or just feed; it is most often measured in

length of material per full revolution of the cutter.

There are two major classes of milling process:

In face milling, the cutting action occurs primarily at the end corners of the milling cutter.

Face milling is used to cut flat surfaces (faces) into the workpiece, or to cut flat-bottomed

cavities.

In peripheral milling, the cutting action occurs primarily along the circumference of the

cutter, so that the cross section of the milled surface ends up receiving the shape of the cutter.

In this case the blades of the cutter can be seen as scooping out material from the work piece.

Peripheral milling is well suited to the cutting of deep slots, threads, and gear teeth.

3. TYPES OF MILLING MACHINES

Milling machines are among the most versatile and useful machine tools due to their

capabilities to perform a variety of operations. They can be broadly classified into the following

types

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5.4 horizontal milling machine

 

5.5 Vertical Milling Machine

1. COLUMN & KNEE TYPE MILLING MACHINES 

Used for general purpose milling operations, column and knee type milling machines are

the most common milling machines. The spindle to which the milling cutter is may be

horizontal (slab milling) or vertical (face and end milling). The basic components are there

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WORK TABLE,

on which the workpiece is clamped using the T-slots. The table moves longitudinally with

respect to the saddle.

SADDLE

Which supports the table and can move transversely?

KNEE

Which supports the saddle and gives the table vertical movements for adjusting the

depth of cut?

OVERARM 

In horizontal machines, which is adjustable to accomadate different arbor lengths.

HEAD

Which contains the spindle and cutter holders? In vertical machines the head may

be fixed or vertically adjustable. 

2. BED TYPE MACHINES 

In bed type machines, the work table is mounted directly on the bed, which replaces the

knee, and can move only longitudinally. These machines have high stiffness and are used

for high production work. 

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6. GRINDING MACHINE

Grinding is used to finish workpieces that must show high surface quality (e.g., low surface

roughness) and high accuThe grinding machine consists of a bed with a fixture to guide and hold

the work piece, and a power-driven grinding wheel spinning at the required speed. The speed is

determined by the wheel’s diameter and manufacturer’s rating.The grinding head can travel across

a fixed work piece, or the work piece can be moved while the grind head stays in fixed position

6.1 grinding machine

1. TYPES

1. BELT GRINDER

which is usually used as a machining method to process metals and other materials, with

the aid of coated abrasives. Sanding is the machining of wood; grinding is the common name for

machining metals. Belt grinding is a versatile process suitable for all kind of applications like

finishing, deburring, and stock removal.

2. BENCH GRINDER

which usually has two wheels of different grain sizes for roughing and finishing

operations and is secured to a workbench or floor stand. Its uses include shaping tool bits or

various tools that need to be made or repaired. Bench grinders are manually operated.

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3. CYLINDRICAL GRINDER

Which includes both the types that use centers and the centerless types? A cylindrical

grinder may have multiple grinding wheels. The workpiece is rotated and fed past the

wheel(s) to form a cylinder. It is used to make precision rods, tubes, bearing races, bushings,

and many other parts.

4. SURFACE GRINDER

Which includes the wash grinder? A surface grinder has a "head" which is lowered to a

workpiece which is moved back and forth under the grinding wheel on a table that typically

has a controllable permanent magnet for use with magnetic stock but can have a vacuum chuck

or other featuring means. The most common surface grinders have a grinding wheel rotating on

a horizontal axis cutting around the circumference of the grinding wheel. Rotary surface

grinders, commonly known as "Blanchard" style grinders, have a grinding head which rotates

the grinding wheel on a vertical axis cutting on the end face of the grinding wheel, while a

table rotates the workpiece in the opposite direction underneath. This type of machine removes

large amounts of material and grinds flat surfaces with noted spiral grind marks. It can also be

used to make and sharpen metal stamping die sets, flat shear blades, fixture bases or any flat

and parallel surfaces. Surface grinders can be manually operated or have CNC controls.

5. TOOL AND CUTTER GRINDER

And the D-bit grinder. These usually can perform the minor function of the

drill bit grinder, or other specialist tool room grinding operations.

6. JIG GRINDER

Which as the name implies, has a variety of uses when finishing jigs, dies, and fixtures.

Its primary function is in the realm of grinding holes and pins. It can also be used for

complex surface grinding to finish work started on a mill.

7. GEAR GRINDER

Which is usually employed as the final machining process when manufacturing a high-55

precision gear? The primary function of these machines is to remove the remaining few

thousandths of an inch of material left by other manufacturing methods.

8. DIE GRINDER

Which is a high-speed hand-held rotary tool with a small diameter grinding bit? They are

typically air driven (using compressed air), but can be driven with a small electric motor

directly or via a flexible

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7. BORING MACHINE

 boring is the process of enlarging a hole that has already been drilled (or cast), by means

of a single-point cutting tool (or of a boring head containing several such tools), for example as in

boring a gun barrel or an engine cylinder. Boring is used to achieve greater accuracy of the

diameter of a hole, and can be used to cut a tapered hole. Boring can be viewed as the internal-

diameter counterpart to turning, which cuts external diameters.

There are various types of boring. The boring bar may be supported on both ends (which only

works if the existing hole is a through hole), or it may be supported at one end (which works for

both through holes and blind holes). Line boring (line boring, line-boring) implies the

former. Back boring (back boring, back-boring) is the process of reaching through an existing

hole and then boring on the "back" side of the workpiece (relative to the machine headstock).

Because of the limitations on tooling design imposed by the fact that the workpiece mostly

surrounds the tool, boring is inherently somewhat more challenging than turning, in terms of

decreased tool holding rigidity, increased clearance angle requirements (limiting the amount of

support that can be given to the cutting edge), and difficulty of inspection of the resulting surface

(size, form, surface roughness). These are the reasons why boring is viewed as an area of

machining practice in its own right, separate from turning, with its own tips, tricks, challenges, and

body of expertise, despite the fact that they are in some ways identical.

7.1 A boring head

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7.2 vertical boring machine

7.3 Horizontal boring machine

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CHAPTER 3

CONCLUSION

Lathe machine, drill machine and other workshop machine the parts of mechanical

industries. All the mechanical equipment is made by this lathe machine.

In the zinc if any tool are broken at any point the worker are prepare this tool on the lathe machine.

Any different tool is also produce on the lathe machine and use of another machine.

Normally in the Hindustan zinc centrifugal pump are not work properly so many time this pump

are repaired by the workers

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REFERENCES

1. http://www.hzlindia.com/products.aspx

2. https://en.wikipedia.org/wiki/Lathe

3.  http://www.hzlindia.com/operations.aspx?ID=2

4. Www. Google .com

5. Charles Singer; E. J. Holm yard and A. R. Hall. A History of Technology, Volume 1: From

Early Times to Fall of Ancient Empires. Oxford University Press; London, England. 1967.

p. 189

6. James E. Land Meyer (15 September 2011). Introduction to Phytoremediation of

Contaminated Groundwater: Historical Foundation, Hydrologic Control, and Contaminant

Remediation. Springer. p. 112. ISBN 978-94-007-1956-9.

7. https://en.wikipedia.org/wiki/Boring_(manufacturing)

8. https://en.wikipedia.org/wiki/Shaper

9. Shaper Mechanism Types

10. Parker, Dana T. Building Victory: Aircraft Manufacturing in the Los Angeles Area in

World War II, p. 73, Cypress.

11. https://en.wikipedia.org/wiki/Planer_(metalworking)

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