materials and lubrication in sheet metal working-27,30,35,36

7/23/2019 Materials and Lubrication in Sheet Metal Working-27,30,35,36

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MATERIALS FOR

SHEET METAL

WORKING



SHEET METAL-INTRODUCTION

Sheet metal is metal formed by an industrial

process into thin, flat pieces.

It is one of the fundamental forms used

in metalworking and it can be cut and bent into a

variety of shapes. Countless everyday objects are

constructed with sheet metal. Thicknesses can

vary significantly; etremely thin thicknesses are

considered foil or leaf, and pieces thicker than

! mm "#.$% in& are considered plate.



The thickness of sheet metal is commonly

specified by a traditional, non'linear measure

known as its gauge.

There are many different metals that can be

made into sheet metal, such

as aluminum, brass, copper, steel, tin,, nickel

and titanium. For decorative uses, important

sheet metals include silver, gold, and platinum.

Sheet metal is used for car bodies, airplane

wings, medical tables, roofs for buildings

(architecture) and many other applications.



STAINLESS STEEL

. !rade "#$ is the most common of the three

grades. %t offers good corrosion resistance while

maintaining formability and weldability. !rade "#"

is not available in sheet form.

&. !rade "' possesses more corrosion resistance

and strength at elevated temperatures than "#$. %t

is commonly used for pumps,valves, chemical

euipment, and marine applications. ". !rade $# is a heat treatable stainless steel, but

it has a lower corrosion resistance than the other

grades. %t is commonly used in cutlery . The only

available finish is dull.



ALUMINIUM

luminum is also a popular metal used in sheet

metal due to its fle*ibility, wide range of

options, cost effectiveness, and other properties.

The four most common aluminium grades

available as sheet metal are ##+$, "##"+$, -#-&+"&, and '#'+T'.

. !rade ##+$ is commercially pure

aluminium, highly chemical and weather

resistant. %t is ductile enough for deep drawingand weldable, but has low strength. %t is

commonly used in chemical processing

euipment, light reflectors, and ewelry.



SHEET METAL

$. (rade )##)'*+ is stronger than ++##, while

maintaining the same formability and low cost. It is

corrosion resistant . It is often used

in stampings, spun and mail boes, cabinets, tanks,

and fan blades. ). (rade %#%$'*)$ is much stronger than )##) while

still maintaining good formability. It maintains high

corrosion resistance. Common applications include

electronic chassis, tanks, and pressure vessels.

. (rade !#!+'T! is a common heat'treated structural

alloy. It is corrosion resistant, and stronger than %#%$,

but not as formable. It loses some of its strength when

welded. It is used in modern aircraft structures.



TOOL MATERIALS



FACTORS TO BE CONSIDEREDBEFORE SELECTING THE TOOL

Stresses on tools

/conomic /fficiency

vailability



DESIRED PROPERTIES OF THE TOOL

igh ardness

igh 0ompression Strength deuate %mpact Strength

igh 1ear 2esistance



The most cheap, easily available and having all the

desired properties is ST//3.



TOOL STEELS

Cold work Tool steels

Hot work Tool Steels

0old+work tool steels are preferred for tools

used to make work pieces without cutting

from ferrous and non+ferrous metals (e.g.

cutting, punching, drawing or spinning

tools).



Cold Work Tool Steels



LUBRICATIONIN SHEET METAL

WORKING



NEED %OR LUBRICATION INSHEET METAL WORKING:

Material ow in the die caity is inuenced by frictional

conditions at the die!wor" piece interface#

Therefore$ a %ood understandin% of the parameters that

a&ect friction is essential and thus a %ood lubrication is

re'uired for producin% &ood"'uality ()!!t $!tal*art(#

(or proper )!at di((i*ation and controllin% !c!((t!$*!ratur!#

Sheet metal parts produced to hae &ood #ni()#

E&ectie lubrication leads to r!duc!d load( on toolin%and wor"piece#

)resence of lubricant *lm reduces amount of directsurface contact between toolin% and wor"piece thusreducin% +!ar and increasin% $!tal li,!-

%ACTORS A%%ECTING



%ACTORS A%%ECTINGLUBRICATION IN SHEET

METAL WORKING-- )RO+,-TIO. -O.+ITIO.S:

/# Stro"e rate

0# Ram speed

1# 2umidity and Temperature

3# Machine -haracteristics

- L,4RI-A.T -2ARA-TERISTI-S:/# 5iscosity

0# (ilm thic"ness

1# )ressure stability

3# Temperature stability

6# Addities



- S2EET MATERIAL :/# (low Stress ! ,TS

0# Surface *nish

1# Thermal properties

3# 7eometry 8thic"ness9

- +IE -2ARA-TERISTI-S:/# Material hardness

0# all surface *nish

1# Thermal properties

3# 7eometry 8contact len%th and pressure9



In (!l!ctin& lubricant( ,or()!!t $!tal ,or$in& *roc!((. t)!

,ollo+in& ,actor( ()ould b!con(id!r!d /

/# Methods of lubricant application

0# Types of addities1# -orrosion control

3# -leanliness and remoal methods

6# Type of formin% process8rollin%$for%in%$drawin%9

;# 2ot wor"in% or cold wor"in%

<# Ease of application of lubricant

=# -ost



Ty*!( o, lubricant(:- Oil(: )etroleum>based oils are widely used as lubricants for

li%ht>duty stampin%$ blan"in%$ and coinin% operations# The useof oil can increase the production rate# )ara?nic oils andnaphthenic oils are e@amples of these lubricants#

- Solubl! Oil(: Soluble oils contain emulsi*ers that allow thedilution of the oils into water# These oils are referred aspreformed emulsions# These oils are normally mi@ed withwater at a dilution ratio of / to 6B#

- S!$i(ynt)!tic(: These lubricants are more easily mi@ed withwater than soluble oils$ because they contain a smalleramount of mineral oil$ usually less than 1B of the totalconcentrate olume#

- Synt)!tic(: Synthetic uids are cate%oriCed by two types:water based and hydrocarbon based# The color of thislubricant normally is haCy or mil"y#

- Dry"%il$ Lubricant(: +ry>*lm lubricants are diided intowater>soluble and waterfree 8Dhot melt9 cate%ories# ater>soluble dry>*lm lubricants are applied in amounts of #6 to /#6



A**lication o, Lubricant(- The proper application of lubricants is important for %ood

lubricant performance and reduction of lubricant waste andenironmental haCards#

- The most commonly used application methods are:

Dri* M!t)od: The simplest and the cheapest method to apply thelubricant$ by drippin% it on the panel or sheet blan"$ but applyin%the desirable amount of lubricant is ery di?cult #

Roll Coatin&: Lubricant applied on the blan" moin% between two

rollers under controlled pressure$ allowin% precise control of theamount of lubricant applied#

El!ctro"D!*o(ition: Lubricant deposited on the panel surfaceusin% electric char%eF used for hi%h>speed applications without anywaste of lubricant$ but re'uires hi%h capital inestment for smallstampin% shops#

Airl!(( S*rayin&: Applies precise amounts of lubricant to localareas$ with minimal waste of lubricant in this method$ but does notwor" with the hi%h>iscosity lubricants#

Mo*( and S*on&!(: Low>cost method still used in a lot of smallstampin% shops to apply lubricants on the panels$ which can resultin e@cessie waste of lubricants$ poor control of the amount oflubricant$ and sloppy wor" enironment#



REFERENCES. 4eutsche /delstahlwerke

&. rval by rcelor 5ittal

". 4esign andbook+2ev"

materials and lubrication in sheet metal working-27,30,35,36

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