Disclosure to Promote the Right To Information

Whereas the Parliament of India has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities, in order to promote transparency and accountability in the working of every public authority, and whereas the attached publication of the Bureau of Indian Standards is of particular interest to the public, particularly disadvantaged communities and those engaged in the pursuit of education and knowledge, the attached public safety standard is made available to promote the timely dissemination of this information in an accurate manner to the public.

इंटरनेट मानक

“!ान $ एक न' भारत का +नम-ण”Satyanarayan Gangaram Pitroda

“Invent a New India Using Knowledge”

“प0रा1 को छोड न' 5 तरफ”Jawaharlal Nehru

“Step Out From the Old to the New”

“जान1 का अ+धकार, जी1 का अ+धकार”Mazdoor Kisan Shakti Sangathan

“The Right to Information, The Right to Live”

“!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता है”Bhartṛhari—Nītiśatakam

“Knowledge is such a treasure which cannot be stolen”

“Invent a New India Using Knowledge”

है”ह”ह

IS 1993 (2006): Cold-reduced electrolytic tinplate [MTD 4:Wrought Steel Products]

IS 1993:2006

1s01 1949:1995(Superseding IS 9025:1993,

IS 13954:1994 and IS 13955: 1994)

Indian Standard

COLD-REDUCED ELECTROLYTIC TINPLATE

( Fourth Revision) -

Ics 77.140.50

@ BIS 2006

BUREAU OF INDIAN STANDARDSMANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG

NEW DELHI 110002

June 2006 Price Group 9

AMENDMENT NO. 1 JULY 2010 TO

IS 1993 : 2006/ISO 11949 : 1995 COLD-REDUCED ELECTROLYTIC TINPLATE

( Fourth Revision )

(Second cover, National Foreword, last para) — Insert the following new para before the last paragraph: ‘The standard also makes a reference to the BIS Certification Marking of the product, details of which is given in National Annex A.’

(Page 22) — Insert the following National Annex A at the end of the standard:

NATIONAL ANNEX A (National Foreword)

‘A-1 BIS CERTIFICATION MARKING The material may also be marked with Standard Mark. A-1.1 The use of the Standard Mark is governed by the provisions of the Bureau of Indian Standards Act, 1986 and the Rules and Regulations made thereunder. The details of conditions under which the licence for the use of Standard Mark may be granted to manufacturers or producers may be obtained from the Bureau of Indian Standards.’ (MTD 4)

Reprography Unit, BIS, New Delhi, India

Wrought Steel Products Sectional Committee, MTD 4

NATIONAL FOREWORD

This Indian Standard (Fourth Revision) which is identical with ISO 11949:1995 ‘Cold-reduced electrolytictinplate’ issued by the International Organization for Standardization (ISO) was adopted by the Bureauof Indian Standards on the recommendation of the Wrought Steel Products Sectional Committee andapproval of the Metallurgical Engineering Division Council.

This Indian Standard was originally published in 1962 and subsequently revised in 1974, 1982 and1993. This revision of the standard has been taken up to align it with ISO 11949:1995 by adoptionunder dual numbering system.

With the publication of this revision, following Indian Standards will be superseded:

Is 9025:1993 Single cold-reduced tinplate and single cold-reduced black-plate electrolytic1s01111-2 :1993 coil and blackpiate coil for subsequent cutting into sheet form (first revis;on)

Is 13954:1994 Double cold-reduced electrolytic tinplateISO 4977-1:1984

Is 13955:1994 Double cold-reduced electrolytic tinplate coil for subsequent cutting intoISO 4977-2:1988 sheets

ISO has cancelled 1S0”111 1-1:1993, ISO 1111-2:1993, ISO 4977-1:1984 and ISO 4977-2:1988 andreplaces with ISO 11949:1995.

The text of ISO Standard has been approved as suitable hr publication as an Indian .Standard withoutdeviations. Certain conventions are, however, not identical to those used in Indian Standards. Attentionis particularly drawn to the following:

a) Wherever the words ‘International Standard’ appear, referring to this standard, they should beas read as ‘Indian Standard’

b) Comma ( , ) has been used as a decimal marker while in Indian Standards, thecurrent practiceis to use a point ( . ) as the decimal marker.

In this adopted standard, reference appears to certain International Standards for which Indian Standardsalso exist. The corresponding Indian Standards which are to be substituted in their places are listedbelow along with their degree of equivalence for the editions indicated:

International Standard Corresponding Indian Standard Degree of Equivalence

ISO 1024:1989 Metallic materials — IS 1586 : 2000 Method for Technically EquivalentHardness test — Rockwell superficial Rockwell hardness test for metallictest (scales 15 N, 30 N, 45 N, 15T, material (scales A-B-C-E-F-G-H-K)30 T and 45 T) (third revision)

ISO 6892 : 1984 Metallic IS 1608:2005 Metallic materials — domaterials —Tensile testing Tensile testing at ambient

temperature (third revision)

In reporting the results of a test or analysis made in accordance with this standard, if the final value,observed or calculated, is to be rounded off, it shall be done in accordance with IS 2:1960 ‘Rules forrounding off numerical values (revise@’.

. ..—.

IS 1993:20061s0 11949:1995

Indian Standard

COLD-REDUCED ELECTROLYTIC TINPLATE

( Fourth Revision)

1 Scope

This International Standard specifies requirements forsingle and double cold-reduced low-carbon mild steelelectrolytic tinplate in the form of sheets or coils forsubsequent cutting into sheets.

Single-reduced tinplate is specified in nominal thick-nesses that are multiples of 0,005 mm, from 0,17 mmup to and including 0,49 mm. Double-reduced tinplateis specified in nominal thicknesses that are multiplesof 0,005 mm, from 0,14 mm up to and including0,29 mm.

This International Standard applies to coils and sheetscut from coils in nominal minimum widths of 500 mm.

Annex E lists the relevant clauses for the selectedproduct.

2 Normative references

The following standards contain provisions which,through reference in this text, constitute provisions ofthis International Standard. At the time of publication,the editions indicated were valid. All standards aresubject to revision, and parties to agreements basedon this International Standard are encouraged to in-vestigate the possibility of applying the most recenteditions of the standards indicated below. Membersof IEC and ISO maintain registers of currently validInternational Standards.

ISO 1024:1989, Mets//;c materials — Hardness test —Rockwell supetiicial test (scales 15N, 30N, 45N, 15Z30T and 45V.

ISO 6892:1984, Metallic materials — Tensile testing.

3 Definitions

For the purposes of this International Standard, thefollowing definition apply.

3.1 electrolytic tinplate Low+arbon mild steelsheet or coil coated on both surfaces with tin that isapplied in continuous electrolytic operation.

3.2 differentially coated electrolytic tinplate:Cold-reduced electrolytic tinplate, one surface ofwhich carries a heavier tin coating than the other.

3.3 single cold-reduced: Term used to describethose products where the steel substrate has beenreduced to the desired thickness in a cold-reductionmill and subsequently annealed and temper rolled.

3.4 double cold-reduced: Term used to describethose products in which the steel base has had a sec-ond major reduction after annealing.

3.5 standard grade tinplate Material in sheet formwhich is the product of line inspection. It is suitable,under normal conditions of storage, for establishedlacquering and printing over the entire surface of thesheet and does not contain any of the following:

a)

b)

c)

d)

pinholes, i.e. any perforation through the wholethickness of the material;

thickness outside the tolerance range specified in10.3;

surface defects which render the material unsuit-able for the intended use;

damage or shape-related defects which render thematerial unsuitable for the intended use.

3.6 second grade tinplate: Material which rep-resents the best sheets rejected from the standardgrade but may contain sheets exhibiting defects insurface appearance and shape of limited extent. Suit-ability for established lacquering and printing over theentire surface of the sheet is not assured.

3.7 batch annealed; box annealed (BA): Annealedby the process in which the cold-reduced strip is an-nealed in tight coil form, within a protective atmos-phere, for a predetermined time-temperature cycle.

1

IS 1993:20061s01 1949:1995

3.8 continuously annealed (CA): Annealed by theprocess in which cold-reduced coils are unwound andannealed in strip form within a protective atmosphere.

, 3.9 finish: Surface appearance of tinplate, deter-mined by the surface characteristics of the steel basetogether with the conditioning of the tin coating whichcan be either flow-melted or unflow-melted.

3.9.1 bright finish: Finish resulting from the use oftemper-mill work rolls that have been ground to a highdegree of polish together with a flow-melted orunflow-melted tin coating.

3.9.2 stone -finish: Finish on flow-melted tinplatecharacterized by a directional pattern, resulting fromthe use of final-mill work rolls that have been groundto a lower degree of polish than those used for thesmooth finish, together with a flow-melted tin coating.

3.9.3 silver finish: Finish resulting from the use oftemper-mill work rolls that have been shot blasted,together with a flow-melted tin coating.

3.9.4 matt finish: Finish resulting from the use oftemper-mill work rolls that have been shot blasted,together with an unflow-melted tin coating.

3.10 coil: Rolled flat strip product which is woundinto regularly superimposed laps so as to form a coilwith almost flat sides.

3.11 Iongitutinal bow; line bow Residual curva-ture in the strip remaining along the direction of roll-ing.

3.12 transverse bow; cross bow Mode of curva-ture in the sheet such that the distance between itsedges parallel to the direction of rolling is less thanthe sheet width.

3.13 centre buckle; full centre Intermittent verticaldisplacement or wave in the strip occurring other thanat the edges.

3.14 dge wave Intermittent vertical displacementoccurring at the strip edge when the strip is laid on aflat surface.

3.15 feather dge; transverse thickness profile:Variation in thickness, characterized by a reduction inthickness close to the edges, at tight angles to thedirection of rolling.

3.16 burr: Metal displaced beyond the plane of thesurface of the strip by shearing action.

3.17 rolling witih: Wdth of the strip perpendicularto the direction of rolling.

3.18 consignment Quantity of material of thesame specification made available for dispatch at thesame time.

3.19 bulk package; bulk: Packaging unit comprisinga base platform or pallet, the sheets and packagingmaterial. (See pallet.)

3.20 pallet Base platform on which a coil is placedtotacilitate ready transportation.

3.21 stillage platform: Base platform on whichsheets are stacked to facilitate packing and readytransportation.

3.22 sample unit 750 m of coil cut into sheets, forthe purposes of sampling.

3.23 fine inspection: Final inspection of the finishedproduct performed by instruments andlor visualexamination at ‘normal production-line speeds.

3.24 anvil effe~ Effect which a hard anvil can produce on the numerical hardness value obtained whena hardness test is performed on very thin sheet SUPported on such an anvil.

4 Information to be supplied by thepurchaser

4.1 General

The following information shall be given in the enquiryand order to assist the manufacturer in supplying thecorrect materiil:

a)

‘b)

c)

d)

e)

the designation as given in clause 5 excluding theannealing code, unless a specific type of annealingis required;

the quantity, expressed on an area or mass basis;

for singlereduced tinplate, the finish required (see6.2.1);

marking requirements for differentially coatedtinplate (see clause 12);

any further special requirements.

NOTE 1 Appropriate classifications are suitable for shapingo~ations such as stamping drawing, folding, beading andbending, and assemb~ work such as joint forming, solder-ing and we~lng. However, for tin coatings less than2,8 @m2, high-speed soft soldering cannot be guaranteed.Welding, for coatings less than 1,4 @m2, cannot be guaran-teed. The end use should be borne in mind when theclassification is selected.

2

IS 1993 :~61s01 1949:1995

4.2 Options

In the event that the purchaser does not indicate hiswish to implement any of the options included in this

,International Standard and does not specify his re-quirements at the time of the enquiry and order, theproduct shall be supplied on the following basis:

a)

b)

c)

d)

e)

f)

g)

h)

with cathodic surface passivation treatment usinga bichromate salt of an alkali metal (see 6.3);

where differential tin coatings are ordered, theheavier coated surface shall be indicated by con-tinuous parallel lines spaced at 75 mm intervals(see clause 12);

for double-reduced tinplate, with a stone surfacefinish (see 6.2.2);

for coils, the location of each joint shall be indi-cated by a piece of non-rigid material and punchedholes (see 11 .3);

for coils, they shall be dispatched with their coresvertical and an internal diameter of 420 mm or508 mm (see 16.1);

for sheets, the direction of the runners of thestillage platform is at the discretion of the pro-ducer but shall be consistent within a consign-ment (see 16.2);

for sheets, the rolling width shall be either of thetwo specified dimensions (see note 2);

with a coating of DOS (see 6.3).

4.3 Additional intimation

In addition to the information in 4.1 and 4.2, the pur-chaser may wish to provide further information to thesupplier to ensure that the order requirements areconsistent with the end use of the product.

The purchaser shall inform the supplier of any modifi-cations to his fabrication operations that will signifi-cantly affect the way in which the tinplate is used.

NOTE 2 When ordering double cold-reduced tinplate, thepurpose of manufacture for which the material is intendedshould be stated. It should be noted that double cold-reduced tinplate is relatively less ductile than single cold-reduced tinplate and has very distinct directional properties,so for some uses, for example for built-up can bodies, thedirection of rolling should be stated. When double cold-reduced tinplate is used for built-up can bodies, the direc-tion of rolling should be around the circumference of thecan so as to minimize the hazard of flange cracking.

5 Designation

5.1 Single-reduced tinplate

‘For the purposes of this International Standard, singl~reduced tinplate is designated “in terms of a temperclassification based on the Rockwell HR30Tm hard-ness values given in table 2.

Single-reduced material covered by this InternationalStandard shall be designated by the following charac-teristics in the given sequence:

a)

b)

c)

d)

e)

f)

g)

a description of the material (either tinplate coil orsheet);

the number of this International Standard;

the temper designation in accordance with table 2;

the type of annealing used by the manufacturer(see 9.1);

the type of finish (see 3.9);

the coating masses and their combinations, E (forequally coated) or D (for differentially coated),together with numbers representing the nominalcoating mass on each surface (see clause 12);

the dimensions, in millimetres:

— for coils, strip thickness x width;

— for sheets, thickness x width x length.

EWMPLE

Single cold-reduced tinplate sheet, in accordance withthis International Standard, of steel grade TH61 +SE(tinplated coating), continuously annealed (CA), stonefinish, equally coated with a coating mass of 2,8 @m2,with a thickness of 0,22 mm, a width of 800 mm anda length of 900 mm shall be designated:

Tinplate sheet ISO 11949- TH61+SE - CA - stone -E 2,8/2,8 - OZ X 800 X 900.

5.2 Double-reduced tinplate

For the purppses of this International Standard, themechanical properties in which double-reduced tin-plate complying with this International Standard issupplied are designated in terms of a system ofmechanical property classifications based on 0,2 YOproof stress given in table 3.

Double-reduced material covered by this InternationalStandard shall be designated by the following charac-teristics in the given sequence:

3

IS 1993:2006

1s0 11949:1995

a)

b).

c)

d)

e)

f)

a description of the material (either tinplate coil orsheet);

the number of this International Standard;

the mechanical property designation (see table 3);

the type of annealing used by the manufacturer(see 9.1);

the coating masses and their combinations, E (forequally coated) or D (for differentially coated),together with numbers representing the nominalcoating mass on each surface (see clause 12);

the dimensions, in millimetres:

-– for coils, strip thickness x width;

— for sheets, thickness x width x length.

EWMPLE

Double cold-reduced tinplate coil, in accordance withthis International Standard, of steel grade T620+SE,continuously annealed (CA), differentially coated withcoating masses of 8,4 g/m2 and 5,6 g/m2, with athickness of 0,18 mm and a width of 750 mm shall bedesignated:

Tinplate coil ISO 11949- T620+SE - CA - D 8,4/5,6 -0,18 X 750.

6 Manufatiuring features

6.1 Manufadure

The purity of tin used to produce the coating shall benot less than 99,85 YO(m/m).

The methods of manufacture of tinplate are the prov-ince o-f the manufacturer and are not specified in thisInternational Standard.

The purchaser shall be informed if any alteration ismade to the method of manufacture that will affectthe properties of the tinplate.

NOTE 3 It is recommended that the manufacturer sup-plies to the purchaser such details of the manufacturingprocess as may assist the purchaser in his efficient use ofthe tinplate.

6.2 Hnish

6.2.1 Single-radumd tinplate

Single cold-reduced tinplate can be supplied witheither a bright, silver, stone or matt finish, and the

finish required shall be specified at the time of order-ing [see 4.1 c)].

The appearance is governed by

a)

b)

c)

the surface characteristics of the steel base whichprincipally Fesult from controlled preparation of thework rolls used during the final stages of temperrolling;

the mass of the coating applied;

whether the tin layer is flow-melted or unflow-melted.

6.2.2 Double-reduced tinplate

Double cold-reduced tinplate is usually supplied with astone surface finish and a flow-brightened tin coating.

6.3 Passivation and oiling

The surface of electrolytic tinplate is normally sub-jected to a passivation treatment and to oiling.Passivation, produced either by a chemical or an elec-trochemical treatment, gives a sutiace with an im-proved resistance to oxidation and improved suitabilityfor lacquering and printing. Unless otherwise agreedat the time of ordering [see 4.2a)], the usual passiva-tion procedure is a cathodic treatment in a solutibn ofa bichromate salt of an alkali metal.

Under normal conditions of transport and storage,electrolytic tinplate shall be suitable for surface treat-ments such as established lacquering and printingoperations.

Tinplate coils and sheets are supplied with an oilcoating. The oil shall be one that is recognized (i.e. bythe relevant national or international authority) asbeing suitable for food packaging. Unless otherwiseagreed at the time of ordering [see 4.2 h)], DOS(dioctyl sebacate) shall be used.

6.4 Defeds

6.4.1 Coils

The producer is expected to employ his normal qualitycontrol and line inspection procedures to ensure thatthe tinplate manufactured is in accordance with therequirements of this International Standard.

However, the production of tinplate coils in continu-ous-strip mill operations does not afford the oppor-tunity for removal of all tinplate that does not complywith the requirements of this International Standard.

4

... .. .. . . . .. . . . .-— ...

At the time of shearing, sheets not conforming to thestandard grade shall be set aside by the purchaser orhis agent.

,The quantity of sheets complying with this inter-national Standard shall be at least 90 YO of any onecoil.

NOTE 4 Items c) and d) in 3.5 cannot be verified byspecific tests and -should be the subject of a specialagreement between the producer and user.

If, when processing tinplate coil, the purchaser (or hisagent) encounters recurring defects whtih in hisopinion seem excessive, it is essential, where practi-cable, that he stops processing the coil and advisesthe supplier.

The purchaser is expected to have adequate handling,roller Ievelling and shearing equipment and inspectionfacilities, and to take reasonable care during theseoperations.

6.4.2 Sheets

Sheets shall not contain any defects as defined in 3.5,when sampled as described in 13.2.

7 SpecMc requirements

Standard grade tinplate shall comply with the appro-priate requirements of clauses 8 to 12.

When tests are carried out to verify compliance withthe requirements of clauses 8 to 10, sample sheetsshall be selected from consignments in accordancewith clause 13.

Coils shall be dispatched as described in 16.1 andsheets shall be packaged as described in 16.2.

8 ~n coating mass

The coating mass, on each surface, shall be ex-pressed in grams per square metre. The lowest valuespecified in this International Standard shall be 1 g/m2on each surface, and no upper limit is specified.Values of preferred coating masses are 1,0 g/m2,1,5 g/m2, 2,0 g/m2, 2,8 glm2, 4,0 .g/m2, 5,0 g/m2,5,6 glmz, 8,4 g/m2 and 11,2 g/m2.

Whatever the coating mass used, the tolerance shallbe as indicated in table 1, and the mass per unit areafor equally and differentially coated tinplate is deter-mined on test pieces taken from samples selected inaccordance with clause 13 and tested in accordancewith 14.2. In cases of dispute, the reference methodgiven in annex A shall be used.

IS 1993:2006

1s0 11949:1995

NOTE 5 -For both equally coated and differentially coatedtinplate, the individual test pieces of the sample may showtin coatings as low as, for example, 80 YOof the minimumaverage coating mass, but it is emphasized that isolatedtest Dieces have no representative value in relation to thecons~gnment under consideration,

Table 1 — Tolerances on tin coating masses

Permissibk deviation forRanges of mass (m) sample average from

per surface nominal coating mass@mz @mz

l,o

IS 1993:20061s0 11949:1995

10 Tolerancesondimensions and shape

10.1 General.

Tolerances on dimensions (i.e. thickness and lineardimensions) and shape (i.e. edge camber, out-of-squareness, lateral weave) are specified in 10.2 and10.3, together with appropriate methods of meas-urement.

NOTE 9 Other geometrical features may be present, suchas burr, edge wave, centre buckle, longitudinal bow andtransverse bow. This International Standard does notspecify methods of measurement and does not specifylimits for these geometrical features, ce~ain of which aresubject to the equipment employed by the purchaser. Theproducer should endeavour to keep the occurrence andmagnitude of burr, edge wave, centre buckle and trans-verse bow to a minimum. He should also endeavour tominimize the variation of the longitudinal bow.

10.2 Coils

10.2.1 Length

The -difference between the actual length and theproducer’s indicated length, measured on any singlecoil, shall not exceed ~ 3 Yo.

The accumulated difference between the actuallengths and producer’s indicated Iengfhs, measuredon at least 100 coils, shall not exceed 0,1 Yo.

NOTE 10 The purchaser normally verifies the length ofstrip in a coil by multiplying the average length of thesheets sheared from the coil by the number of sheetsobtained and adding the accumulated lengths of any otherportions of the coil as received. The average length of thesheets sheared from the coil is normally determined bymeasuring the lengths of at least ten sheets, taken at ran-dom, to an accuracy of 0,2 mm. Coil lengths may bemeasured by other methods, provided that the methodadopted is acceptable to both the producer and purchaser.

1.0.2.2 Wdth

The width of each sample sheet, selected in accord-ance with clause 13, shall be measured fo the nearest0,5 mm. The width shall be measured across thecenfre of the sheet, at right angles to the direction ofrolling, with the sheet lying on a flat surface. Themeasured width shall be not less than the orderedwidth and shall not exceed the ordered width by morethan 3 mm.

Table 2 — Hardness values (HR30Tm) for singl~redud tinplate

Steal grade~

IS 1993:20061s0 11949:1995

10.2.3 Thickness

10.2.3.1 General

‘ The transverse thickness profile shall be measuredusing the micrometer method described “in 14.1.2. Allother thicknesses shall be determined by the weigh-ing method (see 14.1.1 ) or by direct measurementusing the micrometer method. However, in cases ofdispute and for all retests, except for the transversethickness profile, the weighing method shall be used.

10.2.3.2 -Individual sheets

When shearing a coil, sheets shall be eliminated ifthey deviate from the nominal thickness by more than*8,5 Yo.

10.2.3.3 Average thickness of a consignment

The average thickness of a consignment, determinedby the weighing method described in 14.1.1, on thesample sheets selected in accordance with 13.1, shallnot deviate from the ordered nominal thickness bymore than

a) t 2,5 YO for consignments comprising more than15000 m; or

b) t 4 YO for consignments comprising 15000 m orless.

10.2.3.4 Thickness variation across the width

The thickness of each of the two individual testpieces, determined in accordance with 14.1.1, shallnot deviate from the actual average thickness of thewhole sheet by more than 4 Yo.

10.2.3.5 Feather edge (transverse thicknessprofile)

The minimum thickness, when measured by the mi-crometer method described in 14.-1.2, shall not differfrom the actual centre thickness of the sheet by morethan 8 Yo.

10.2.4 Edge camber of coi[s

Edge camber is the maximum deviation (in the planeof the sheet) of an edge from a straight line forming achord to its extremities= (see figure 1).

The edge camber expressed as a percentage 01chord length, is c-alculated using the followingmula:

thefor-

Edge camber =Deviation (D)

Length of chord (6 m)x 100

The edge camber, measured over a distance (chordlength) of 6 m, shall not exceed 0,1 YO(i.e. 6 mm).

. Dimensions in metres

W rolling width

D: deviation from a straight line

Figure 1 — Edge camber of coils

7

IS 1993:20061s0 11949:1995

10.2.5 Lateral weave (short pitch camber) of coils

Lateral weave is the deviation of a mill-trimmed edge.

from a straight line lying in the same plane and form-ing a chord to it over a relatively short distance.

The lateral weave, measured over a chord length of1 m, shall not exceed 1,0 mm when measured prior toshearing.

NOTE 11 If the coil is used for scroll shearing, the per-missible values should be agreed upon between the manu-facturer and purchaser.

10.3 Sheets

10.3.1 Linear dimensions of sheets

Each sample sheet shall be such that a rectangle ofthe ordered dimensions can fit into it. To determinethe linear dimensions, lay ~~ch sample sheet, selec-ted in accordance with 13.2.2, on a flat surface andmeasure the length and width to the nearest 0,5 mmacross the centre of the sheet.

The dimensions of each sample sheet shall be notless than the ordered dimens’mns and neither dimen-sion shall exceed the ordered dimension by more than3 mm.

10.3.2 Thickness of sheets

10.3.2.1 General

The transverse thickness profile shall be measuredusing the micrometer method described in 14.1.2. Allother thicknesses shall be determined by the weigh-ing method (see 14.1.1 ) or by direct measurementusing the micrometer method. However, in cases ofdispute and for all retests, except for the transversethickness profile, the weighing method shall be used.

10.3.2.2 Individual sheets

The thickness of each of the individual sample sheets,selected from a consignment in accordance with13.2.2, shall not deviate from the ordered nominalthickness by more than t 8,5 Yo.

10.3.2.3 Average thickness of a consignment

The average thickness of a consignment, determinedby the weighing method described in 14.1.1 on thesample sheets selected in accordance with 13.2.2shall nol deviate from the ordered nominal thicknessby more than

a)

b)

f 2,5 YO for a consignment of more than20000 sheets; or

* 4 YOfor a consignment of 20000 sheets or less.

10.3.2.4 Tolerances on local thi~kness within asheet (crown)

The thickness of each of the two individual testpieces, determined by the weighing method de-scribed in 14.1.1, shall not deviate from the actualaverage thickness of the whole sheet by more than4 Yo.

~0.3.2.5 Feather edge (transverse thickness*refile)

The minimum thickness, when measured by the mi-crometer method described in 14.1.2, shall not differfrom the actual centre thickness of the sheet by morethan 8 Yo.

10.3.3 Edge camber of sheets

Edge camber is the maximum deviation (in the planeof the sheet) of an edge from a straight line forming achord to it (see figure 2).

The edge camber, expressed as a percentage of thechord length, is calculated using the following for-mula:

Edge camber =Deviation (D)

Length of chord (L)x 100

For each sample sheet, the edge camber shall notexceed 0,15 YO.

10.3.4 Out-of-squareness of sheets

Out-of-squareness is the deviation of an edge from astraight line drawn at a right angle to the other edgeof the sheet, touching one corner and extending tothe opposite edge (see figure 3).

The out-of-squareness, expressed as a percentage, iscalculated using the following formula:

Out-of-squareness =Deviation (A)

Sheet dimension (B)x 100

For each sheet in the sample, the out-of-squarenessshall not exceed 0,20 Yo.

8

‘IS 1993: 2W61s0 l19@ :1995

L length of chord

W rolling width

D: deviation from a straight line

Hgure 2 — Edge mmber of sheet

B

.—. — .—. — .—. — .—. — .—

A: deviation

B: length-or width of the sheet measured at a right angle to an edge

Hgure 3 — Out-of-squareness of sheets

9

IS 1993:20061s01 1949:1995

11 Joints w=thina coti

11.1 General“

The producer shall ensure continuity of the coilswithin the limits of the lengths ordered, if necessaryby means of electrically welded joints made after coldreduction. Requirements relating to the numbers,locations and dimensions of the joints permittedwithin a coil are given in 11.2 to 11,4.

11.2 Number of joints

The number of joints in a coil shall not exceed three inlengths of 10000 m.

11.3 Lwation of joints

The location of each joint in a coil shall be indicatedclearly.

NOTE 12 The location of each joint may be indicated, forexample by the insertion of a piece of non-rigid materialand punched holes. However, alternative methods may beagreed between the producer and purchaier at the time ofenquiry and order.

11.4 Dimensions of joints

11.4.1 Thicbass

The .tital thickness of any joint shall not exceed threetimes the nominal thickness of the material formingthe joint.

11.4.2 Overlap

In any lap joint, the total length of overlap shall notexceed 10 mm. The free overlap shall not exceed5 mm (see figure 4).

D{rection of rol~ing

a4

a:

b:

total length of overlap

free overlap

12 Marting -ofdifferentiallycoatedcold-rduced tinplate

In order to distinguish between tinplate with differen-tial tin coatings and tinplate with equal coatings on thetwo surfaces, differentially coated tinplate shall bemarked on one surface on~.

Differentially coated tinplate shall be marked either

a) on the heavily coated surface by dull, straight,continuous parallel lines up to 1 mm wide andspaced at 75 mm intervals; or

b) on the lightly coated surface by alternate inter-rupted, dull, straight, parallel lines spaced at75 mm intervals.

If no option is indicated at the time of ordering, OPtion a) will be adopted kee 4.2 b)].

The following examples show how to indicate themarked side and its position when ordering:

D 2;8/5,6: Marked on the 2,8 coated side. Themarks are on the top of sheets or on the outside ofthe coil.

D 5,6/2,8: Marked on the 5,6 coated side. Themarks are on the top of sheets or on the outside ofthe coil.

2,8/5,6 D: Marked on the 5,6 coated side. Themarks are on the bottom of sheets or on the insideof the coil.

5,6/2,8 D: Marked on the 2,8 coated side. Themarks are on the bottom of sheets or on the insideof the coil.

Annex C gives details of an alternative marking sys-tem for certain coating combinations only.

13 Sampling

‘13.1 coils

13.1.1&neral

When tests are carried out to assess compliance withthe requirements for coating mass (see clause -8), tol-erances on dimensions and shape (see clause 10) andmechanical properties (see clause 9), samples of thetinplate coil shall be selected in accordance with13.1.2.

After the coils in a consignment have been cut intorectangular or scrolled sheets, the sheets deemed notto be of standard grade tinplate shall be excluded. ‘Thestandard grade sheets that remain shall be sampledon the basis of units of strip 750 m in length, in ac-

Hgure 4 — Joint overlap cordance with 13.1.2.3.

10

IS 1993: 2W61s01 1949:1995

NOTE 13 Because the samples have to be cut from coilsin the consignment, the taking of samples is usualiy carriedout by the purchaser during his normal shearing operation.

The purchaser shall allow the producer, or his rep-.

resentatives, to be present during the sampling andsubsequent testing and to be able to confirm that theidentities of the samples and test pieces correspondwith the coils in the consignment supplied.

13.1.2 Selection of samples

13.1.2.1 Lots and units

For the purpose of sampling, eachcoils shall be considered as one lot.

13.1.2.2 Selection of sample units

consignment of

For lots comprising up to and including 20 units,4 sample units shall be selected at random.

For lots comprising more than 20 units, 4 units shallbe selected at random from each 20 units and fromany remaining part of 20 units.

13.1.2.3 Selection of sample sheets

From each sample unit selected in accordance with13.1.2.2, the following sample sheets shall be takenat random:

a)

b)

for verification of the coating mass and mechani-cal properties: two sheets;

for verification of the dimensions and shape: fivesheets.

13.2 Sheets

13.2.1 General

If tests are carried out to ascertain whether thesheets in a consignment comply with the require-ments for coating mass (see clause 8), tolerances ondimensions and shape (see clause 10), and mechani.cal properties (see clause 9), sample sheets shall beselected in accordance with 13.2.2.

13.2.2 Sele@ion of sample sheets

13.2.2.1 Number of bulk packages

Sample bulk packages shall be selected at randomfrom the total number of bulk packages, at a rate of20 YOrounded to the nearest greater whole number ofbulk packages and subject to a minimum of four bulkpackages.

For consignments comprising less than four bulkpackages, each bulk package shall be taken as asample.

13.2.2.2 Number of sheets

From each of the sample bulk packages selected inaccordance with 13.2.2.1, take at random:

a) for verification of standard grade material (see3.5), sheets at the rate of 1 % per bulk package;

b) for verification of mechanical properties and coat-ing mass, two sheets;

c) for verification of dimensions, sheets at the rateof 0,5 YO per bulk package, to the nearest wholenumber of sheets.

NOTE 14 The rate of sampling is specified on a percent-age basis (except for the verification of mechanical proper-ties and coating masses) because the number of sheetsper bulk package may vary, for example between 1000 and2000.

14 Test -hods

14.1 Thickness

14.1.1 Weighing method for determination ofthickness

14.1.1.1 Determine the thickness of each samplesheet as follows:

a) weigh the sheet to give the mass, to -the nearest2 g;

b) measure the length and width of the sheet, to thenearest 0,5 mm, and calculate the area;

c) calculate the thickness of the sheet, to the near-est 0,001 mm, using the following formula:

Thickness (mm) =

Mass (g)

= Area (mm2) x 0,00785 (g/mm3)

14.1.1.2 To determine the average thickness for aconsignment, calculate the arithmetic mean of thecalculated thicknesses of all the sample sheets repr~senting the consignment.

14.1.1.3 To determine the variation in thicknesswithin each sample sheet, take two test pieces Y (seefigure 5) from the sheet. weigh each test piece to thenearest 0,01 g, measure the length and width of eachtest piece to the nearest 0,1 mm, and calculate thethickness of each test piece to the nearest 0,001 mmusing the formula given in 14.1 .1.1 c).

11

—————. -

IS 1993:20061s0 11949:1995

Dimensionsin millimetres

25 200

I -------- ____________[

I z: 0xI!II

:1 ‘ z 1 -i+t ---~

I I1 II II iII II

I Im # Y,N 1I

DIx

I -------------- , ---------

Direction of rolling

M125X: test pieces for the coating mass

Y: test pieces for hardness and determination of local thickness variation within a sheet

Z: test pieces for tensile or spfingback tests

figure 5 — Lo~tion of test pi-s

14.1.2 Micrometer method for measurement ofthickness

Measure the thickness using a hand-perated, spring-Ioaded micrometer to an accuracy of 0,001 mm:

a) for transverse thickness profile, 6 mm from themill-trimmed edge;

b) for all other thicknesses, 10 mm from the mill-trimmed edge.

NOTE 15 It is recommended that the micrometer shouldhave a ball-ended shank and a curve&sutiace base anvil.

14.2 Tincoatingmasses

14.2.1 Test pi-

From each sheet selected in accordance with clause 13,three test pieces, each of an accurately determinedarea not less than 2500 mmz, and preferably in theform of discs, shall be carefully prepared. These testpieces shall be selected at edg~entr~dge locations(positions X in figure 5) along a line normal to the di-rection of rolling. Ensure that the edge test piecesclear the edges of the sheet by a minimum of 25 mm.

12

14.2.2 Method of determination

The tin coating mass shall be expressed in grams oftin per square metre to the nearest 0,1 @m2.

For routine quality control purposes, the coatingmasses may be determined by any of the recognizedand acceptable analytical methods but, in cases ofdispute and for all retests, the method described inannex A shall be the referee method.

Whether tin coating determinations are made on indi-vidual or grouped test pieces, the tin coating mass ofa consignment shall be taken as the average of all theresults.

14.3 Tensileteats

14.3.1 Test pi-es

For each sheet selected in accordance with clause 13,cut two rectangular test pieces approximately200 mm x 25 mm wide with the direction of rollingparallel to the length of the test piece, at the positionmarked Z in figure 5. Ensure that the edge test piecesclear the edges of the sheet by a minimum of 25 mm.Before carrying out the tensile teat described in14.3.2, artificially age the test pieces at 200 ‘C for20 min.

IS 1993:20061s0 11949:1995

14.3.2 Test method

Determine the 0,2 YO proof stress as described inISO 6892 using the conditions specified in annex B of

“ ISO 6892:1984 for thin products and test piece type 1,i.e. width 12,5 mm + 1 mm and original gauge lengthLO,of 50 mm.

Carry out one test on each of the test pieces selectedin accordance with 14.3.1, i.e. two tests per sheetselected.

Calculate the representative proof stress for the con-signment as the arithmetic mean of all the proofstress results on all the sample sheets taken from theconsignment.

15 Retests

15.1 coils — Dimensions, coating mass andmechanical properties

If any of the results obtained are unsatisfactory, themeasurements for that particular prope, tv shall berepeated twice on new samples; on each occasionusing the sampling specified in 13.1. If the results onboth repeated tests meet the stated requirements,the consignment represented shall be deemed tocomply with this International Standard, but if theresults of either of the retests fail to meet the statedrequirements, the consignment represented shall bedeemed not to comply with this Internatknal Stan-dard.

15.2 Sheets

15.2.1 Standard grade

In the event of the samples inspected for standardgrade not complying with the defined requirements in3.5, further sheets shall be taken at random and in-spected at a rate of 5 YOper bulk package.

15.2.2 Dimensions, coating mass andmechanical properties

If any of the results obtained are unsatisfact~, themeasurements for that particular prQperty shall berepeated twice on new samples; on each occasionusing the sampling specified in 13.2. If the results onboth repeated tests meet the stated requirements,the consignment represented shall be deemed tocomply with this International Standard, but if theresults of either of the retests fail to meet the statedrequirements, the consignment represented shall bedeemed not to comply with this International Stan-dard.

16 Dispatchand packaging

16.1 Coils

Unless otherwise requested at the time of ordering,coils shall be dispatched with their cores in a verticalposition [see 4.2e)] (the other option would be withthe cores horizontal). The internal diameters of thecoils shall be either (420 y~~)mm or (508 ~~~)mm.

NOTE 16 Tinplate strip is usually supplied in consignmentsof coils with outside diameters of at least 1200 mm, but alimited number of coils with smaller outside diameters maybe included in the consignment.

16.2 Sheets

The sheets shall be supplied in bulk packages inwhich-the numbers of sheets are multiples of 100.

NOTES

17 The sheets are customarily packed on a stiliage plat-form forming a bulk package weighing approximately be-tween 1000 kg and 2000 kg.

18 If the purchaser has any preference for the direction ofthe runners of the stillage platform, his requirementsshould be agreed with the producer and stated on the order[see 4.2f)l.

13

IS 1993:20061s0 11949:1995

Annex A(normative)

Volumetric method for the determination of the tin coating mass(iodine method)

A. 1 Principle

The tin coating is dissolved in hydrochloric acid andthe tin in an aliquot is reduced to the bivalent statewith metallic aluminium. The tin in the reduced stateis determined by titration with potassium iodate stan-dard solution.

The effective range of the method is from 0,5 g/m2 upto 50 g/m2 and the reproducibility is ~ 0,1 g/m2.

A.2 Reagents and materials

A.2.1 General

During the analysis, use only reagents of recognizedanalytical grade and only distilled water.

Freshly prepare and, where necessary, filter all sol-utions.

Prepare reagents A.2.4, A.2.5 and A.2.6 with freshlyboiled distilled water to ensure that the solutions areas free from dissolved oxygen as is practicable.

A.2.2 Hydrochloric acid, p = 1,16 g/ml, diluted 3 + 1.

Dilute 750 ml of hydrochloric acid (p = 1,16 g/ml) to1 000 ml with water.

A.2.3 Iron(lll) chloride, 100 g/1solution.

Dissolve 100 g of hydrated iron(lll) chloride in watercontaining 100 ml of hydrochloric acid (p = 1,16 g/ml)and dilute to 1 000 ml with water.

A.2.4 Potassium iodate standardc(l/6 K103) = 0,05 mol/1. For use only withtinplate, equally coated.

Dissolve 1,7835 g of potassium iodate,

solution,ele-ctrolytic

previouslydried to constant ‘mass at 180 ‘C, and 19“g of po~-assium iodide in water containing 0,5 g of sodiumhydroxide and dilute to 1 000 ml with water.

1 ml of this solution k equivalent to 0,002967 g of tin.

A.2.5 Potassium iodate standard solution,cO/6 K103) = 0,025 mol/1. For use only with electro-lytic tinplate, differentially coated.

Dissolve 0,9018 g of potassium iodate, previouslydried to constant mass at 180 ‘C, and 1 g of potass-ium iodide in water containing 0,5 g of sodium hydrox-ide and dilute to 1 000 ml with water.

1 ml of this solution is equivalent to 0,001484 g of tin.

A.2.6 Starch solution.

Prepare a suspension of 1 g of soluble starch in 10 mlof water and add to 100 ml of boiling water. Boil for2 min to 3 min and cool.

A.2.7 methyl ether, p = 0,72 g/ml technical grade.

A.2.8 Platinum wire, approximately 750 mm longand 0,6 mm in diameter, formad into a flat spiral oftwo turns and approximately 125 mm in diameter (seefigure A.1).

A.2.9 Aluminium metal foil, 99,99 YO[m/m) purity(tin-free) 0,25 mm thickness.

A,2.10 Carbon dioxide, oxygen-free

A.2.? 1 Cellulose lacquer, a suitable lacquer thatdries in air.

A.2.12 Acetone, analytical reagent (AR) grade.

A.3 Apparatus

A suitable assembly for carrying out the reduction oftin consists of a 500 ml wide-neck conical flaskmarked at a volume of 200 ml. The flask is fitted witha rubber bung containing a bent gas inlet tube, a smallLiebig-type condenser and a rubber-sealed tube forburette entry at the titration stage (see figure A.1 ).

14

IS 1993:20061s0 11949:1995

G

A

.

–B

A.4 Procedure

A.4.1 Eledrolytic tinplate -equally coated

A.4.1.1 Mn coating mass equal to or greater than2S g/m2

Degrease with diethyl ether (A.2.7) the test pieces (inthe form of discs) taken from sheets as described in14.2.1. Place the spiral of platinum wire (A.2.8) cen-trally in a shallow dish (see figure A.2). Place six of thediscs in a circle on the platinum wire and carefullypour 150 ml of hydrochloric acid (A.2.2) into the dish.

As soon as the tin coating is completely dissolvedfrom both faces, leaving the steel surfaces exposed(see note 19), transfer the acid quantitatively to a1000 ml one-mark volumetric flask. Wash twice with25 ml of water, transferring the washings to the flask.

I Repeat the whole procedure with the remaining six

—- C

Key

A Gas exit

B Water out

C C02 ent~

D Rubber bung

E 500 ml wide-neck flask

F Test solution

G Rubber seal and tube for burette ent~

H Water in

J Small Liebig condenser

figure A.1 — Apparatus for the redutiion of tin

discs, combining the acid and washings in the ~amevolumetric flask, and finally dilute to the mark withwater.

Transfer a 100 ml aliquot of the solution to the 500 mlwide-neck conical flask (A.3), add 75 ml of hydro-chloric acid (A.2.2) and 10 ml of iron(lll) chloride sol-ution (A.2.3) and dilute to the 200 ml mark with water.Add 2 g of aluminium metal foil (A.2.9). Insert therubber bung fitted with a small bebig condenser, acarbon fiioxide entry tube and a rubber-sealed buretteentry tube (see figure A. 1). Connect the apparatus tothe appropriate supply points and pass carbon dioxidegas (A.2.1 O) through for 5 min to displace the airwithin the flask. Heat carefully until boiling starts,avoiding vigorous evolution of hydrogen. Continueboiling for 5 min to 10 min after dissolution of thealuminium metal. Cool quickly to less than 20”°C,maintaining an adequate supply of carbon dioxide.

Remove the burette entry tube seal, add 5 ml ofstarch solution (A.2.6) and titrate with potassiumiodate standard solution (A.2.4) to a permanent bluecolour.

NOTES

19 The time required for complete dissolution depends onthe coating mass. It may vary from about 3 min for anE 2,8R,8 coating to about 10 min for an E 11,2/1 1,2 mating.

20 Care is necessary when adding the aluminium foil, toavoid a violent reaction; it is recommended that the foil becut into small sections beforehand.

15

IS 1993:20061s0 11949:1995

Approximate dimensions in millimetres

A

B

Key

A Shallow dish

B ~nplate specimen

C Platinum wire

figure A.2 — Arrangement of specimens for dissolution of tin

A.4.I.2 fin coating mass less than 2,5 g/m2

Degrease with the diethyl ether (A.2.7) the test pieces(in the fOrm of discs) taken from sheets as describedin 14.2.1. Place the spiral of platinum wire (A.2.8) cen-trally in a shallow dish (see figure A.2). Place six of thediscs in a circle on the platinum wire and carefullypour 150 ml of hydrochloric acid (A.2.2) into the dish.

As soon as the tin coating is completely dissolvedfrom both faces, leaving the steel surfaces exposed(see note 19), transfer all the acid to a 1000 ml one-mark volumetric flask. Wash twice with 25 ml ofwater, transferring the washings to the flask. Repeatthis procedure with the remaining six discs, pouringthe acid and washings into the same flask, and finallydilute to the mark with water.

Transfer 200 ml of the solution to the 500 ml wide-neck flask (A.3), add 30 ml of hydrochloric acid (A.2.2)and 10 ml of iron(lll) chloride solution (A.2.3). Continuewith the reduction -and titration as described inA.4.1. 1, but using the potassium iodate standard sol-ution (A.2.5)-as titrant.

A.4.2 Eledrol~ic tinplate — differentiallycoated

Degrease with diethyl ether (A.2.7) the test pieces (inthe form of discs) from sheets as described in 14.2.1and coat the faces carrying the heavier tin coatingwith a cellulose lacquer (A.2.1 1). Allow to dry for15 rein, apply a second coat of lacquer and allow todry for 1 h. Place the spiral of platinum wire (A.2.8)centrally in a shallow dish (see figure A.2). Place six ofthe discs in a circle with the unlacquered faces incontact with the platinum wire. Carefully pour 150 mlof hydrochloric acid (A.2.2) into the dish.

As soon as the tin coating is completely dissolvedfrom the untacquered faces, leaving the steel surfacesexposed (see note 19), transfer the acid -quantitativelyto a 1000 ml one-mark volumetric flask. Wash twicewith 25 ml of water, transferring the washings to theflask. Repeat the whole procedure with the remainingsix discs, combining the acid and the washings in thesame volumetric flask, and finally dilute to the markwith water. Dry the discs and keep them for determi-nation of the coating on the lacquered faces.

16

IS 1993:20061s0 11949:1995

Transfer a 100 ml aliquot of the solution to the 500 miwide-neck conical flask (A.3), add 75 ml of hydro-chloric acid (A.2.2) and 10 ml of iron(lll) chloride sol-

. ution (A.2.3) and dilute to the 200 ml mark with water.Continue with the reduction and titration as in A.4.I.1,but using the potassium iodate standard solution(A.2.5) as titrant.

Remove the lacquer from the test pieces used aboveby swabbing with cotton wool soaked in acetone(A.2. I 2). Place six of the discs with the unstrappedsurface uppermost in a circle on the platinum wire andcontinue as above.

A.5 Expressionof results

Calculate the average coating mass m, in grams persquare metre, from the following equation:

m=vxcx5,935xlo5A

where

V is the volume, in millimetres, of the potassiumiodate solution;

c is the concentration, in molespotassium iodate solution;

A is the total test piece area,metres.

per Iitre, of the

in square milli-

17

.- ... --..--——.-

1S 1993:20061s0 11949:1995

Annex B(normative)

Springbacktest for routine determinationof proof stressfor—double-reduced

This is not the reference method. In all cases of dis-pute, the method described in 14.3 (i.e. ISO 6892) isto be used.

B.1 Principle

The springback test provides a simple and rapidmeans of estimating the tensile yield strength ofdouble-reduced products from measurement of thick-ness and angle of springback of a rectangular striptest piece, after bending through 180° around a cylin-drical mandrel and then releasing.

B.2 Test pieces

The test pieces used are identical to those for thetensile test described in 14.3.1.

B.3 Test method

Make one test on each of the test pieces obtained inaccordance with B.2 (i.e. two tests per sheetselected). Carry out the test using the SpringbackTemper Tester model G.671).

In making the test, strictly obsewe the operationalinstructions provided with the Springback TemperTester. The principal steps in the test are:

a)

b)

c)

d)

e)

material

measure the thickness of the tinplate test piece,to the nearest 0,001 mm;

insert the test piece into the tester and fix it firmlyin the testing position by gently tightening theclamping screw using light finger pressure;

bend the test piece through an angle of 180°around the mandrel by a gentle swing of theforming arm;

return the forming arm to its “start” position andread and record the springback angle by sightingdirectly over the test piece;

remove the test piece from the tester and. usingthe recorded thickness of the test piece and thespringback angle, determine the appropriatespringback index value from a suitable conversionformula (e.g. Bower) agreed between the preducer and purchaser.

NOTE 21 Calibrate each new Springback Temper Testerusing the standard tensile test (see 14.3) or another“reference” Spritigback Temper Tester. In addition, sincemalfunctions arising, for example from excessive wear orinadvertent abuse of the test equipment, may not be readilyapparent, it is recommended that the Springback TemperTest readings should be regularly compared with readingsfrom the standard tensile test or a “reference” SpringbackTemper Tester. It is also recommended that such directcrosschecks be further supplemented by the frequent useof reference samples of known proof stress.

1) The Sprmgback.Temper Tastar model G.67 is an example of a suitabla produti available commercially. This information is givan for theconvenience of users of this International Standard and does not constitute an endorsement by ISO of this produ~.

18

IS 1993:20061s0 11949:1995

AnnexC(informative)

marking system for differentiallycoatedtin~ate

The marking system consists of parallel straight lines up to 1 mm wide, the distance between the linesthe coating masses.

The following spacings should be used:

Designation tine spacing

D 5,6/2,8 12,5 mm

D 8,4/2,8 25 mm

D 8,4/5,6 25 mm alternating with 12,5 mm

D 8,4/1 1,2 37,5 mm alternating with 25 mm

D 11 ,2/2,8 37,5 mm

D 11,2/5,6 37,5 mm alternating with 12,5 mm

An illustration of the marking system is given in figure C.1.

NOTE 22 This alternative marking system may be used for certain coating combinations only.

Designation

D 5,6/2,a

D a8412.8

DB,4/5,6

D 8,4/11,2

Dll,2/2,a

D 11,2/5,6

Spacings

I I I I I I I I I I

indicating

112,5 mm I

2S mm

25 mm 12 S mm

37 S mm 2S mm

37 S mm

I37 S mm 12 S mm

IJ I I I I !

figure C.1 — Alternative marting system for differentially coated el-rolytic tinplate

IS 1993:20061s01 1949:1995

Recommended

Annex D(i~forrnative)

Rockwellhardnessvaluesfor double-reducedtinplate

D.1 General

Recommended hardness values. . determined as d=scribed in D.2 and D.3, are given in table D.1.

Table D.1 — Hardness values (HR30Tm)for doubl~raducad tinplate

Average RmWell hardnessSteel grade

(previous(HR30Tm)1]

designation) Nominal Range for sampleaverage

T550+SE (DR 550) 73 &3~80+SE (DR 580) 74 *3T620+SE (DR 620) 76 &3

T660+SE (DR 660) 77 *3

T690+SE (DR 690) 80 *3

1) k is impotiant to distinguishHR30Tm from HR30T, the for-mer denoting that depressions on the under surface of the testpiece are permitted (d. ISO 1024).

D.2 Test pieces

The hardness tests shall be carried out prior to lac-quering or printing.

From each of the sample sheets obtained in accord-ance with clause 13, take two test pieces125 mm x fi 25 mm from the positions marked Y infigure 5.

NOTE 23 The test pieces N) taken for the determinationof thickness variations within the individual sample sheetsmay also be used for tha hardness determinations, whereappropriate.

Before carrying out the hardness tests in accordancewith D.3, remove the tin coating and artificially agethe test pieces at 200 O.Cfor 20 min.

Polish material with a shot blast finish using emerypaper of grade 600.

D.3 Test mathod

Determine the Rockwell HR30Tm indentation hard-ness either

a)

b)

directly, in accordance with ISO 1024; or

indirectly, on relatively thin sheets (e.g. 0,22 mmand thinner), by determining the HR15T hardnessin accordance with ISO 1024 and then convertingthe HR15T values to HR30Tm values usingtable D.2.

Make three hardness measurements on each of thetest pieces taken in accordance with D.2.

Calculate the representative hardness, for the con-signment as the arithmetic mean of all the hardnessmeasurements on all the sample sheets taken fromthe consignment.

To measure the indentation hardness, use a Rockwellsuperficial hardness testing machine, employing the30Tm or 15T scales (see ISO 1024), as appropriate.

Carry out the tests on test pieces from which all or-ganic coatings have been removed. Avoid testing nearthe edges of the test pieces because of a possiblecantilever effect.

20

Is 1993: am1s01 1949:1995

Table D.2 — Rockwell HR15T valuesand their HR30Tm equivalents

HR15T valueEquivalent

HR30Tm value

92,0 80,5

91,5 79,0

91,0 78,0

I 90,5 I 77,5 I90,0 76,0

89,5 75,5

89,0 74,5

88,5 74,0

88,0 73,0

87,5 72,0

I 87.0 I 71,0 I

86,5 70,0

86,0 69,0

85,5 68,0

85,0 67,0

I 84,5 I 66.0 I

84,0 65,0

83,5 63,5

83,0 62,5

82,5 61,5

I 82.0 I 60,5 I

81,5 59,5

81.0 58,5

80,5 57,0

80,0 56,0

79,5 55,0

79,0 54,0

I 78.5 I 53,0 I78,0 51,5

77,5 51,0

I 77,0 I 49,5 I

76,5 49,0

76,0 47,5

21

.

IS 1993:20061s011949: lggs

Annex E(informative)

Relevantclauses for seletied produd

Clause Clause headingcoil Shti

number -SR1) DR2) SR1) DRZ)

1 Scope x x x x

-2 Normative references x x x x

3 Definitions x x x x

4 Information to be supplied by the purchaser x x x x

5 Designation

5.1 SingI&reduced tinplate x x

5.2 Doubi&reduced tinplate x x’

6 Manufacturing features x x x x

7 Specific requirements x x- x x

a Tin coating mass x x x x

9 Mechanical properties

9.1 General x x x x

9.2 Singl@reduced tinplate x x

9.3 Double-reduced tinplate x x

10 Tolerances on dimensions and shape

10.1 General x x x x

10.2 Coils x x

10.3 Sheets x x

11 Joints within a coil x x

12 Marking of differentially coated cold-reduced tinplate, x x x x

13 Sampling

13.1 Coils x x

13.2 Sheets x x

14 Test methods

14.1 Thickness x x x x

14.2 Tin coating masses x x x x

14.3 Tensile tests x x

15 Retests

15.1 Coils — Dimensions, coating mass and mechanical properties x- x

15.2 Sheets x x

16 Dispatch and packaging

16.1 Coils x x

16.2 Sheets x x

Annex A Volumetric method for the determination of the tin coating mass(iodine method) x x x x

Annex B Sprin back test for routine determination of proof stress forFdoub ereduced material x x

Annex C Alternative marking system for differentially coated tinplate x x x x

Annex D Recommended Rockwell hardness values for doubl~reduced tinplate x x x x

1) Singlereduced

2) DoublWeduced

22

—.———— .—.-——— .—_ .—_

Bureau of Indian Standards

BIS is a statutory institution established under the Bureau of/ndjan Standards Act, 1986 to promotiharmonious development of the activities of standardization, marking and quality certification of

. goods and attending to connected matters in the country.

Copyright

BIS has the copyright of all its publications. No part of these publications maybe reproduced in anyform without the prior permission in writing of BIS. This does not preclude the free use, in the courseof implementing the standard, of necessary idetails, such as symbols and sizes, type or gradedesignations. Enquiries relating to copyright be addressed to the Director (Publications), BIS.

Review of Indian Standards

Amendments are issued to standards as the need arises on the basis of comments. Standards are

also reviewed periodicatty; a standard along with amendments is reaffirmed when such reviewindicates that no changes are needed; if the review i~dicates that changes are needed, it is taken

up for revision. Users of tndian Standards should ascertain that they are in possession of the latestamendments or edition by referring to the latest issue of ‘BtS Catalogue’ and ‘Standards : MonthlyAdditions’.

This tndian Standard has been devetoped from Doc : MTD 4 (4584). *

Amendments Issued Since Publication

Amend No. Date of Issue Text Affected

BUREAU OF INDIAN STANDARDS

Headquarters:

Manak Bhavan, 9“Bahadur Shah Zafar Marg, New Delhi 110002Telephones :23230131, 23233375, ‘2323 9402 Website : www.bis.org.in

“Regional Offices :

Central :

Eastern :

Northern :

Southern :

Western :

Branches:

Manak Bhavan, 9 Bahadur Shah Zafar MargNEW DELHt 110002

1/1 4 C. 1. T. Scheme Vlt M, V. t. P. Road, KankurgachiKOLKATA 700054

SCO 335-336, Sector 34-A, CHANDIGARH 160022

C. t. T. Campus, IV Cross Road, CHENNAI 600113

Manakataya, E9 MlDC, Marol, Andheri (East)MUMBAI 400093

Telephones

[

2323761723233841

[

23378499,2337856123378626,23379120

[

26038432609285

~2254 1216,22541442

~2254 2519,22542315

[

28329295,2832785828327891,28327892

AHMEDABAD. BANGALORE. BH.OPAL. BHUBANESHWAR. COIMBATORE.FARtDABAD. GHAZIABAD. GUWAHATI. HYDERABAD. JAIPUR. KANPUR.LUCKNOW. NAGPUR. PARWANOO. PATNA. PUNE. RAJKOT.THtRUVANANTHAPURAM. VISAKHAPATNAM.

Printed at New India Printing Press, Khurja, Indis