इंटरनेट मानक

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.

“जान1 का अ+धकार, जी1 का अ+धकार” “प0रा1 को छोड न' 5 तरफ”

Mazdoor Kisan Shakti Sangathan Jawaharlal Nehru
“The Right to Information, The Right to Live” “Step Out From the Old to the New”

IS 3704 (1966): Methods for sampling of light metals and

their alloy products [MTD 13: Ores and Raw Materials]

“!ान $ एक न' भारत का +नम-ण”

Satyanarayan Gangaram Pitroda
“Invent a New India Using Knowledge”

“!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता ह”

है”
ह
Bhartṛhari—Nītiśatakam
“Knowledge is such a treasure which cannot be stolen”
( Reaffirmed 2001 )
 IS:3704-1966

Indian Standard
METHODS FOR SAiWLING OF LIGHT
METALS AND THEIR ALLOY PRODUCTS

Methods of Sampling Sectional Committee, SMDC 4

Chairman Representing
DR A. V. SUKHATME The Tats Iron L Steel Co Ltd, Jamehedpur
Members
SEEI V. D. A~AXWA~ Light Metals and Their Alloy Products Sectional
Committee, SMDC 10, IS1
SHBI 0. P. MATHUR ( Alternate)
SERI J. C. BAXEXJEE Refrqctories Seotional Committee, SMDC 18, IS1
DB U. N. BH~ANY Indian Iron & Steel Co Ltd, Burnpur
SHBI J. N. BUBMAN ( Alternate )
DB M. K. BOSE Precious Metals Sectionai Committee, SMDC 13,
IS1
CHE~ST & META~LLUROIST, Railway Board ( Ministry of Railways )
SOUTH EASTEBN‘ RAILWAY,
KHAEA~PUX
CHEMIST & METALLTJRQIST,
RDSO, CHITTARANJAN ( Alternate ) i
S~BI R. N. DATTA Directorate General of Ordnance Factories (Minis-
try of Defence), Calcutta
SHEI D. K. CHAKRAVARTY ( ntrernate )
SHRI D. SEN ( Alternate )
SHRI S. K. DUTTA Directorate General of Inspection ( Ministry of
Defence )
SHRI J. BRATTACHARJEE ( Alternate )
SHRI 8. B. FIRKE Copper and Copper Alloys Sectional Committee,
SMDC 11, IS1
SERI CEINTAMANI SEARMA ( Alternate )
SEMI S. S. VAIDYANATHAN ( Alternate )
SHRI A. GUHA Cast Iron & Malleable Cast Iron Sectional Com-
mittee, SMDC 9, IS1
SHBI S. 8. HONAVA~ Italab Private Ltd, Bombay
SERI J. P. PATEL ( Alternate )
DR N. JAYARAM~ Essen & Co, Bangalore
SHRI K. N. GUWRAJACHAR ( Alternate )
SHRI R. M. KRISENAN Foundry Sectional Committee, SMDC 17, IS1
SHRI D. B. LAHIRI Indian Statistical Institute, Cahtta
DR A. MATTHAI ( Alternate 1

( Continued on page 2 )

INDIAN STANDARDS INSTITUTION

MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARC
NEW DELHI 1

/
.
IS:3704- 1966
(Continuedfrom page 1 )
Members Representing
Sam N. MAJUMDAR Indian Non-ferrous Metals Manufacturers’
Association, Calcutta
SHRI M. M. MOUD~ILL ( Alternate )
DB N. T. MATHEW Ststistioal Organization ( Ministry of Defence )
SHRI S. P. A~ARWALA ( Alternate )
SHRI N. C. MITBA Government of India, Mint ( Ministry of Finance )
DR M. K. BOSE ( Alternate )
SHRI S. N. MUKERJI National Test House, Calcutta
SHRI A. K. BHATTACHARJEE( Afternate )
DR G. MUERERJEE Ferro Alloys Sectional Committee, SMDC 8, ISI;
and Steel Tubes, Pipes and Fittings Sectional
Committee, SMDC 22, IS1
SHRI D. S. MURTY Ores and Raw Materials Sectional Committee,
SMDC 16, IS1
SHRI E. K. N. NAMBIAR Directorate General of Supplies & Disposals
( Inspection Wing ); Steel Castings Sectional
Committee, SMDC 20, ISI; and Pig Iron
Sectional Committee, SMDC 24, IS1
SHRI G. V. HALWE Directorate General of Supplies & Disposals
( Akrnate ) ( Inspection Wing )
SHRI ,A. PADMANABHAN Steeisorgings Sectional Committee, SMDC 21,

SKI A. SAN~AMESWARA RAO Methods of Chemical Analysis Sectional Com-

mittee, SMDC 2, IS1 I
SIIILID. K. RAY Wrought Steel Products Sectional Committee,
SMDC 6, IS1
SHRI G. V. D. UPADHYAYA Indian Bureau of Mines (Mini&v of Mines &
Metals), Nagpur ’ ”
SHRI V. V. 5. R. H. RAO ( Alternate )
SHRI S. VISWANATRAN Methods of Physical Tests Sectional Committee,
SMDC 3, IS1
SHRI B. N. SIN~H, Director General, IS1 ( Ex-officio Member )
Deputy Director ( Statistics )

Secretary
SRRI Y. K. BRAT
Deputy Director ( Statistics ), IS1

Subcommittee on Sampling of Light Metals and Their Alloy

Products, SMDC 4: 5

Convener
SHRI N. MAJUMDAR Indian Aluminium Co Ltd, Calcutta

Members
SHRI V. D. A~AEWAL Aluminium Corporation of Indict Ltd, Calcutta
SRRI H. K. SHAH Jeewan Lsl ( 1929 ) Ltd, Caloutta
SHRI P. K. AMBANI ( Alternate )
SARI M. B. SHANEAR Hindustan Aeronautics Ltd, Bangalore

2
 IS:3704- 1966

Indian Standard
METHODS FOR SAMPLING OF LIGHT
METALS AND THEIR ALLOY PRODUCTS

0. FOREWORD
0.1This Indian Standard was adopted by the Indian Standards Institu-
tion on 5 August 1966, after the draft finalized by the Methods of
Sampling Sectional Committee had been approved by the Structural
and Metals Division Council.

0.2 The indigenous production and use of light metals and their alloy
products have considerably increased during the last few years. Besides,
the versatility of these metals and their alloy products is likely to further
enhance their consumption in the various industries. It is, therefore,
imperative that at this stage of development and expansion of the light
metal industry, due consideration is given to the sampling procedures
which will help in proper and objective evaluation of the physical/
chemical characteristics of these products.

0.2.1 Proper quality control during the process of manufacture would

also substantially reduce the quality fluctuations of the ultimate
products. The sampling procedures recommended in this standard,
therefore, include the provisions for both process control and product
inspection.
0.3 The recommendations made in this standard are intended to meet
the needs of sampling of light metals and their alloy products for general
engineering purposes. As regards the requirements of aircraft industry;
it was felt desirable to have a separate standard on the sampling of such
metals in view of the necessity to having more rigid inspection and
control provisions.
0.4 This standard contains clauses 4.3.1 and 4.4.1 which call for agree-
ment between the purchaser and the supplier.

0.5 In reporting the results of test or analysis, if the final value observed
or calculated, is to be rounded off, it shall be done in accordance with
IS : 2-1960*.

*Rules for rounding off numerical values ( revised ).

3
IS : 3704 - 1966

1. SCOPE
1.1 This standard prescribes the methods for sampling and the criteria
for conformity for light metals and their alloy products. Broad outlines
with regard to the controls to be exercised during the manufacturing
process have also been indicated.

1.1.1 The sampling of light metals and their alloy products used in
the aircraft industry has not been covered in this standard.

2. TERMINOLOGY

2.0 For the purpose of this standard, the following definitions shall
apply *
2.1 Item - A unit such as an ingot, casting, forging, bar, rod, wire,
plate, sheet, strip, etc, meant for inspection/testing.

2.2 Lot - A collection of items of light metals and their alloy products
of one type (such as, ingots, plates, bars, etc) and size ( such as, weights
for ingots, thickness for plates and cross-section for bars ) manufactured
from a single melt, cast or heat.

2.3 Defect -Failure to meet the requirement imposed on an item with

respect to a single characteristic.

2.4 Defective - An item having one or more defects.

2.5 Acceptance Number - The maximum permissible number of

defectives in the sample for acceptance of the lot.

2.6 Acceptable Quality Level (AQL) - The maximum percent defective

that, for the purpose of sampling of light metals and their alloy products
can be considered as satisfactory process average.

NOTE- When a purchaser designates some specific value of AQL, he

indicates to the supplier that his ( the purchaser’s ) acceptance sampling plan will
accept the reat majority of the lots that the manufacturer sdhmits, provided that
the process $average level of percent defective in these lots be not greater than the
designated value of A&L. Thus, the A&L is a designated value of percent
defective that the purchaser indicates will be accepted most of the times
( approximately 89 to 99 percent ).

2.7 Supplier - The party supplying the material. The supplier may or
may not be the actual manufacturer of the material.

2.8 Purchaser - The party purchasing the material. The term

‘ purchaser ’ shall also cover person or persons expressly authorized in
writing by the purchaser to act on his behalf for inspection of the
material.

4
 IS : 3784 - 1966

3. PROCESS INSPECTION
3.1 The object of inspecting light metals and their alloy products by
the purchaser is to ensure their conformity to the specification require-
ments, whereas inspection done by the manufacturer during production
is to ensure conformity to relevant specifications as also to maintain
more uniform quality. For production control, the manufacturer should
take representative samples of the material at regular intervals to
control the quality fluctuations. The inspection levels given in Table 1
are recommended for routine control over the manufacturing process.
3.2 Methods of Drawing Samples
3.2.1 Ingots - The required number of samples shall be prepared by
pouring spoonfuls of molten metal into moulds of desired sizes, and
obtaining heavily chilled test ingots. Care shall be taken to avoid dust
and slag.
3.2.2 Castings - The required number of test specimens shall be cast
either integrally or separately for each melt. In the case of large and
highly stressed castings the test pieces should be cast both before and
after pouring the castings. The actual position of the tensile test pieces
integrally cast may depend upon the size, intricacy and the highly
stressed regions.
NOTE -- It should be emphasized that separately cast test bars indicate only
the properties of the metal before entry into the mould and bear little relation to
the properties of the metal in the castings; and that tho data obtained’on actual
castings may be entirely different and more valuable than those obtained from
separately cast or cast-on test bars.
3.2.2.1 Samples for chemical analyses should be cast in chill moulds
or drilled directly from the castings or from used mechanical test speci-
mens representative of the casting.
3.2.3 Forgings - In the preparation of test samples the following
points shall be taken care of:
a>Cast billets or extrusion
harmful internal defects;
blanks for finished forgings are free from

b) Heat treated pieces from test-coupon forged from stock are tested;
Cl Integrally forged blanks which should be representatives of the
XgMy stressed regions are tested, enszzr+g &a& t)3c Bow 2ine.9
follow the contour;
4 Pieces from the forging itself are tested in addition to those from
initial rolled and extruded forging-blanks; and
e) Flow-lines, residual stress concentrations, grain structures and
responses to heat treatment are studied.
NOTE -Such characteristics such as toughness, grain structure, flow and
residual stress concentrations of actual forgings ma.y be entirely different and more
valuable than t,hose obtained from separately or even integrally forged blanks.
 TABLE 1 RECOMMENDED LEVELS OF INSPECTION/TESTING ..

( Clarrse 3.1 )
I
SL UNIT OF FREQUENCIESOF INSPECTION/NO. OF TESTS FOB CI r
NO. INSPECTION ,__---__----------___-__-----_-.
‘Visuel Dimensional Physical Chemical E
Charac- Cha,racteristics Properties Analysis
teristics
(1) (2) (5) (f3
9 Ingots, notch bars, 2 for batch melting (one
shots, etc, for taken at the beginning and
remelting or for use the other at the end of
in steel production pouring )
One for every 5000 kg or
part thereof for continu-
ous melting
o\ ii) Eigot for fabrication All One for every 10 or less - Same as above
iii) Casting All One for every 10 or less 3 standard test One for each batch of cast-
in case of permanent / samples for a ings poured from a melt
moulds lot
Every casting for sand
moulds
iv) Forging All One for every 10 or less 3 standard test 2 from the items heat
samples for a treated in a single furnace
lot charge
v) Bar, rod, wire or All One for evefy 10 items 3 items for a lot 1
shape* or less Need not he done in case
vi) Sheet, plate or strip* All One for every 10 items 3 items for a lot adequate tests have been
or less i conducted on ingots for
vii) Pipe or tube* All One for every 10 items 3 items for 8 lot I fabrication
or less _I

*For bars, rods, sheets, plates, pipes and tubes which are supplied in the coil form, both the end portions
may be checked for visual and dimensional characteristics.

.
 IS : 3704 - 1966

3.2.3.1 For chemical analysis, the drillings may be taken from the
centre of the solid forgings. For this purpose the forging from which
i
the mechanical test specimens are prepared may be used.

3.2.4 Extruded and Rolled Products-Mechanical test specimens

shall be prepared in the as-received condition and after heat treatment,
if any. In the case of products intended for highly stressed members,
test specimen shall be drawn from extruded sections of each original
cast billet.

3.3 For effective production control, the use of statistical quality control
technique? is also recommended and helpful guidance may be obtained
in this respect from IS : 397-1952*.

3.4 On the basis of the process inspection data, the manufacturer may
issue relevant test certificate to prove the conformity of a lot to the
requirements of any specification.

3.4.1 When such test certificate cannot be made available to the

purchaser or when the purchaser so desires, the procedure laid down
in 4 shall be followed for judging the conformity or otherwise of a lot of
light metals and their alloy products to the requirements of relevant
specification.

4: LOT INSPECTION

4.1 The samples shall be selected and examined for each lot (see 2.2 )
separately for ascertaining their conformity to the requirements of the
relevant specification.

4.2 The number of items to be selected from a lot shall depend upon the
size of the lot and shall be in accordance with co1 (1) and (2) of
Table 2. All these items shall be taken at random from the lot either
with the help of a suitable random number table or any other suitable
means.

4.3 All the items as drawn under 4.2 shall be examined for visual
characteristics such as workmanship, finish and freedom from defects,
in accordance with the details given in the relevant specification. Any
item shall be considered as a defective if it ,is non-conforming with
respect to any of the visual characteristics under consideration. If the
number of defective items found in the sample is less than or equal to
the corresponding acceptance number given in co1 (3) of Table 2,

*Method for statistical quality control during production by the use of control
chart.

7
IS : 3704- 1966

the lot shall be declared as donforniing to the requirements of visual

characteristics. If however, the number of defective items is found to
be greater than the corresponding acceptance number, the lot shall be
deemed as not having met the requirements of visual characteristics.

TABLE 2 SCALE OF SAMPLING AND PERMISSIBLE NUMBER OF

DEFECTJVES FOR VISUAL AND DIMENSIONAL CHARACTERISTICS
( Clauses 4.2, #4.3 and 4.4 )

No. OF’ ITEMS FOR VISUAL FOR DIMENSIONAL

IN THE LOT CHARACTERISTICS CHARACTERISTICS
r__--_---__~ ~-----h -----7
x0. of Items Acceptance No. of Items Acceptance
to be Selected Number to be Selected Number
(1) (2) (3) (4) (5)
up to 15
16 to 25 s” 0” 5
3 :
26 2, .50 13 8 0
20 : 8: 0
1:: :: 100
150 32 2 0
151 .. 300 50 3 32
301 ;; 500 80 5 50 :
501 ,) 1000 12R I 80 3
1001 ,, 3000 200 125 5
3 001 ,, 10000 31.5 :4”
.~ 200 7
10 001 and above 500 21 315 10

NOTE - The associated A&L’s ( see 2.6 ) for visual characteristics and dimen-
sional chax%%cteristics~ar’e2.5 percent and 1.5 percent, respectively. These AQL
values will strictly hold good only in the case of larger lots.

4.3.1 In the case of those lots which have been found unsatisfactory
according to 4.3, all the items in the lot may, depending upon the agree-
ment between the purchaser and the supplier be inspected for visual
characteristics and the defective ones removed.
4.4 The lot which has been found satisfactory in respect of visual charac-
teristics (see 4.3) shall next be tested for dimensional characteristics
like thickness, length, etc. Th e number of items required for this pur-
pose shall be in accordance with co1 (1) and (4) of Table 2 ( these may
be chosen from the sample items already selected for the purpose of
examination of visual characteristics ). Any item failing to meet one or
more dimensional requirements shall be considered as a defective. If
the number of defectives found is less than or equal to the correspond-
ing acceptance number given in co1 (5) of Table 2, the lot shall be
deemed as having met the dimensional requirement of the relevant
specification, otherwise not.

8
 IS :3704-1966

4.4.1 In the case of those lots which have been found unsatisfactory
according to 4.4, all the items in the lot may, depending upon the
agreement between the purchaser and the supplier, be inspected for
dimensional characteristics and the defective ones removed.
4.5 The lot which has been found satisfactory in respect of visual and
dimensional requirements ( see 4.3 and 4.4 ) shall next /be tested for
physical characteristics like tensile strength, bend test, hardness, etc.
The items required for this purpose shall be taken at random from those
already drawn ( see 4.2 ) in accordance with co1 (1) and (2) of Table 3.

TABLE 3 SCALE OF SAMPLING FOR PHYSICAL CHARACTERISTICS

No. OF ITEMS No. OF ITEMS
IN THE LOT TO BE SELECTED
(1) (2)

up
51 to .50
to 150 3"
151 500 5
501 i&d above 8

4.5.1 From each of the items so chosen (see 4.5) the required
number of test specimen shall be prepared for conducting the physical
tests specified. The manner of preparation of test specimen as well as
their dimensions shall be in accordance with the relevant specifications.
4.5.2 From the different test results for each of the measurable
characteristics the average ( x ) and range ( R ) shall be calculated as
follows:
The sum of test results
Average (2 ) =
The number of test results
Range (R) = The difference between the maximum and mini-
mum values of the test results
4.5.2.1 If the specification limit for the characteristic is given as
a minimum then the value of the expression (2 - kR ) shall be
calculated from the relevant test results. If the value so obtained is
greater than or equal to the minimum limit, the lot shall be declared
as conforming to the requirement of that characteristic.
4.5.2.2 If the specification limit for the characteristic is given as
a maximum, then the value of the expression ( f + kR ) shall be
calculated frbm the relevant test results. If the value so obtained is
less than or equal to the maximum limit, the lot shall be declared as
conforming to the requirement of that characteristic.

9
IS : 3704 - 1966

4.5.2.3 If the characteristic has two-sided specification limits then

the value of the expression ( x - kR ) and ( x + kR ) shall be calculated
from the relevant test results. If the values so obtained lie between the
two specification limits, the lot shall be declared as conforming to the
requirement of that characteristic.

4.5.2.4 The value of the factor k referred to in 4.5.2.1 to 4.5.2.3

shall be chosen in accordance with Table 4 depending upon the desired
acceptable quality level ( see 2.6 ).

TABLE 4 VALUES OF k FOR ACHIEVING DIFFERENT ACCEPTABLE

QUALITY LEVELS

ACCEPTABLE QUALITY LEVEL, VALUE OF k

I PERCENT
2.5 to 4.5 0.4
1-O and up to 2.5 0'5
Less than 1-O 0.6

4.5.3 In the case of those characteristics like the bend test which
are not measurable on a continuous scale, the lot shall be considered
as conforming to the requirement of the specification if each of the test
results is found to be satisfactory.

4.5.3.1 In case any test specimen representing an item fails in any

of the physical tests, two additional specimens drawn from the same item
shall be subjected to the particular test in which failure has occurred to
account for any testing error. If both these additional specimens pass
the particular test the item from which they are drawn shall be con-
sidered as satisfactory.
4.6 For each lot, a minimum of two analyses shall be made for the
determination of the various chemical constituents of the alloy as laid
down in the relevant specification.
4.6.1 In the case of finished products, chemical analysis should
preferably be done by remelting or alternatively by getting test specimens
which are cast along with ingots for fabrication. Taking specimens
from the item itself should be the last resort.

4.6.2 In the case of clad material, drillings or chips shall be obtained

from the selected items from the core only, that is, after stripping the
clading. For the purpose of removing the clad material etching the
sheet with Keller’s reagent is recommended. The etching L ay be done
by dipping the sample in reagent and cleaning it every 15 minutes or so
till the clad material is completely removed. A cross section of the

10
 Is:3704-1966

sample piece under microscope may be checked to ensure the complete

removal of the clad material.
4.6.3 All other general principles of preparing the samples needed
for chemical analysis shall be in accordance with IS : 1817-1961*.
4.6.4 The lot shall be-deemed as conforming to the chemical require-
ments of the relevant specification if both the analyses are found to be
satisfactory.

*Methods of sampling non-ferrous metals for chemical analysis.

11
 INDIAN STANDARDS
ON

Quality Control and Sampling

Quality Control
IS: Rs

397-1952 Method for statistical quality control during production by the

use of control chart (tentative) .. . ... ... ... 8.00
1548-1960 Manual on basic principles of lot sampling ... . .. 7.00
2500 ( Part I )-1963 Sampling inspection tables: Part I Inspection by
attributes and by count of defects ... . .. ... 690
2600 ( Part II )-1965 Sampling inspection tables: Part II Inspection by
verirtbles for percent defective : . . . .. ... ... 6.50

Sampling of Ores and Materials

IS:
436 ( Part I )-1964 Methods for sampling of coal and coke: Part I Sampling
of coal (revised) . .. ... . .. ... ... 590
436 ( Part\11 )-1965 Methods for sampling of coal and coke: Part II
Sampling of coke (revised) . .. ... . .. ... 3’00
1289-1960 Methods for sampling of mineral gypsum ... ... ... 3’50
1405-1960 Methods of sampling iron ore . .. ... ... ... 3.00
1449-1961 Methods of sampling manganese ore .. . .. ... 3.00
1472 ( Part I )-I959 Methods of sampling ferro-alloys, Part I ... . .. 2’00
1472 ( Part II )-1962 Methods of sampling ferro-alloys, Part II . .. . .. 260
1811-1961 Methods of sampling foundry sands ... . .. ... 3’00
1817-1961 Methods of sampling non-ferrous metals for chemical analysis . .. 200
1999-1962 Methods of sampling bauxite ... . .. ... . .. 3.50
2051-1962 Methods for sampling of leather footwear .., . .. ... 1'50
1 2109-1962 Methods of sampling dolomite, limestone and other allied
materials . .. ... . .. .. l ... ... 3.50 \
2213-1962 Methods of sampling thermosetting moulding materials . .. 1’50
2245-1962 Methods of sampling quartzite ... ... . .. . .. 3.50
2246-1963 Methods of sampling fluorspar ( fluorite ) . . . .. ... 3’00
2614-1964 Methods for sampling of fasteners ... . .. ... 2.00
2817-1965 Methods for sampling of coated abrasives ... . .. ... 1’50
9535-1966 Methods of sampling hydraulic cements . .. ... ... 2’50
3704-1966 Methods for sampling of light metals and their alloy products ... 2.50