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UDC 621.643
Ref. No.: lSO/R 13 - 1955 (E)
IS0
I NT ERN AT I ON AL ORGAN I2 AT I ON FOR
STAN DARD IZ AT I O N
IS0 RECOMMENDATION
R 13
CAST IRON PIPES,
SPECIAL CASTINGS AND CAST IRON PARTS
FOR PRESSURE MAIN LINES
lst EDITION
November 1955
COPYRIGHT RESERVED
The copyright of IS0 Recommendations and IS0 Standards
belongs to IS0 Member Bodies. Reproduction of these
documents, in any country, may be authorized therefore only
by the national standards organization of that country, being
a member of ISO.
For each individual country the only valid standard is the national standard of that country. ,
Printed in Switzerland
Copies to be obtained through the national standards organizations.
Also issued in French and Russian.
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BRIEF HISTORY
The IS0 Recommendation R 13 on Cast Iron Pipes, Special Castings and
Cast Iron Parts for Pressure Main Lines was prepared by Technical Committee
ISO/TC 5, Pipes and fiffings, the Secretariat of which is held by the Asso-
ciation suisse de Normalisation.
At its meeting in Zurich in May 1951, the Technical Committee decided
to assign the investigation into standardization of cast iron pipes to the Sub-
Committee ISO/TC 5/SC 2, Cast iron pipes, fittings and their joints, the
Secretariat of which was allocated to France.
The French Member Body drafted a first proposal, which was adopted at
the Sub-Committee's meeting in Zurich in October 1951. The basic document,
and a few alterations proposed at the January 1952 Paris meeting, were consid-
ered at the April 1952 plenary meeting in Milan and, allowing for reservations
stated in the Milan Resolution No. 9, adopted by the Technical Committee as
a Draft IS0 Recommendation.
The Draft was distributed to all the IS0 Member Bodies in March 1953, and
approved by a majority. In view of observations submitted by various Member
Bodies, the Secretariat made some amendments in the text of the Draft.
The revised text, which is that of the present IS0 Recommendation, was
approved by the following 20 Member Bodies (out of a total of 34):
Austria Israel Portugal
Chile Italy Spain
Denmark Japan Sweden
France Mexico Switzerland
Germany Netherlands United Kingdom
Hungary New Zealand Yugoslavia
Ireland Pakistan
The revised text of the Draft IS0 Recommendation was submitted by
correspondence to the Members of the IS0 Council which decided, in
1955, to accept it as an IS0 RECOMMENDATION.
March
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IS0 Recommendation R 13 March 1955
CAST IRON PIPES.
SPECIAL CASTINGS AND CAST IRON PARTS
FOR PRESSURE MAIN LINES
CONTENTS
Page
FOREWORD . 7
Comments on Section I . Technical specification . 7
Comments on Section II . Joints . 8
Comments on Section III . Pipes . 9
Comments on Section IV . Special castings . 10
SECTION I . TECHNICAL SPECIFICATION . 13
Clause 1 . Scope .
14
Clause 2 . Types of joints . 14
Clause 3 . Special castings . 14
Clause 4 . Marking . 15
Clause 5 . Quality of metal used .
15
Clause 6 . Quality of pipes and special castings .
15
Clause 7 . Tolerances on the external diameter of the barrel, the internal
diameter of the socket, and the depth of the socket . 16
Clause 8 . Tolerances on thickness .
16
Clause 9 . Tolerances on length .
17
Clause 10 . Permissible deviation from a straight line .
17
Clause 11 . Tolerances on weight . 17
....................
Clause 12 . Mechanical tests 18
..................... 20
Clause 13 . Testing results
Clause 14 . Brinell hardness test . 20
Clause 15 . Hydraulic tests . 21
Clause 16 . Coating . 22
Clause 17 . Inspection . 22
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IS0 / R 13 . 1955 (E)
SECTION II . JOINTS 23
........................
I
Table J 1 . Dimensions of sockets and spigots . 24
Table J 2 . Special castings . Dimensions of sockets and spigots . 25
Tab€e J 3 . Dimensions of flanges . 26
Table J 4 . Standard flange drilling .
27
SECTION III . PIPES . 29
I
Table T 1 . Socket and spigot pipes . Class LA . 30
............
Table T 2 . Socket and spigot pipes . Class A 31
Table T 3 . Socket and spigot pipes . Class B . 32
Table T 4 . Flanged pipes . Sand cast . Class B . 33
Table T 5 . Flanged pipes, centrifugally cast with screwed flanges -Class B 34
SECTION IV . SPECIAL CASTINGS . 35
Table T 10 . Flanged sockets . 36
Table T 11 . Flanged spigots . 37
Table T 12 . Collars . , 38
Table T 13 . Double socket 1/4 bends . 39
Table T 14 . Double socket 1/8 bends . 40
Table T 15 . Double socket 1/16 bends . 41
. .
Table T 16 Double socket 1/32 bends 42
Table T 17 . Double socket tees with flanged branch . 43
Table T 18 . Tees: all sockets . 46
Table T 19 . Crosses: all sockets . , , . 48
Table T20 . Double socket tapers , . 49
Table T21 . Caps . 51
Table T22 . Plugs . 52
Table T30 . Double flanged 1/4 bends . 53
Table T31 . Double flanged 1/4 duckfoot bends . 54
Table T 32 . Double flanged 1/8 bends . 55
Table T 33 . All flanged tees . , . , . , . , . 56
Table T34 . All flanged crosses . , . 59
Table T35 . Double flanged tapers , . , . 60
62
Table T 36 . Blank flanges .
I
i
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IS0 / R 13 - 1955 (E)
CAST IRON PIPES,
SPECIAL CASTINGS AND CAST IRON PARTS
FOR PRESSURE MAIN LINES
FOREWORD
The IS0 Recommendation R 13 includes four sections:
I. TECHNICAL SPECIFICATION
II. JOINTS
111. PIPES
IV. SPECIAL CASTINGS
Comments on Section I - Technical specification
This specification applies generally to pipes, special castings and cast iron
parts of all kinds for pressure mains, and chiefly to pipes and specials with
sockets for lead joints (l).
It also applies to pipes and specials with other types of joints, particularly
rubber joints. However, the characteristics of these joints, many of
which are patented, are not detailed: they remain the subject of private agree-
ment between manufacturers and users.
Castings with such joints may keep the overall measurements of castings
with lead joints, which will facilitate the use by the manufacturer of inter-
changeable patterns allowing accurate and speedy manufacture.
With regard to socket joints (see clause 2), two different types have
been included, in which the centreing bead is part of the interior of the socket
or formed on the outside of the pipe spigot.
Centrifugal casting in a metallic mould does not allow a bead to be cast
on the spigot of the pipe. The two types of joint, however, have been included
because the alternative method is still used; the respective dimensions of the
two types of joint are such that interchangeability is always possible.
The flanges normally have a machined facing strip and drilled holes; this
does not exclude the possibility, in certain cases, of having rough-cast flanges
where particularly accurate moulding processes are used.
In general, the specials (see clause 3) have a sufficiently great resistance
to internal pressure for all the current uses. Different methods of reinforce-
ment have been allowed, however, particularly in cases where high working
(1) Although spun pipes at present comprise the greater part of world production, sand cast pipes have
been included, as they are still made by some manufacturers or in certain diameters.
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pressures must be applied to specials with large branches in which the stresses
in the metal are important.
The requirements of the draft specification drawn up in 1938 by the
ISA/5a Technical Committee concerning the quality of the cast iron (see clause 5)
have all been kept. They are sufficiently precise and leave to the manufacturer
the choice between the different permissible manufacturing processes.
The limit of superficial hardness has been brought to the Brinell number 230
(see clause 6) to correspond to the value adopted in several national standards.
This value takes into account the increase in resistance offered by the spun
pipes.
The socket tolerances (see clause 7) have been fixed in relation to the
normal caulking space.
It is logical to provide for equality between the plus and minus tolerances.
Similarly, the socket tolerances are smaller than the barrel tolerances :
in fact, the socket of the castings has a greater thickness than the barrel and,
therefore, greater rigidity.
The value adopted for the density of the cast iron (see clause 11) is 7.15:
it lies between the values fixed formerly in different countries, which vary
between 7 and 7.25. The value of 7.15 ensures good practical agreement
between the calculated and real weights.
The results to be attained for the mechanical tests (see clause 13) do not
show any change when compared with those adopted in 1938 by the ISA/5 a
Technical Committee. Only one new value for tensile resistance has been
introduced for spun pipes of a nominal diameter greater than No. 600,
which were not manufactured at that time.
The cast iron pipes, specials and castings for mains of different diameters
are generally made in thicknesses suitable to the highest working pressures
generally used (l).
In some cases, it may happen that these castings are intended to be
submitted to working pressures giving an insufficient margin of safety as com-
pared with the works test pressures (see clause 15). In such cases it will be for
the users to state this and for the manufacturers to provide for a suitable
increase in thickness and in test pressure.
on Section II - Joints
Comments
Cast iron pipes, specials and castings for mains may be manufactured in
the range of nominal diameters from No. 20 to No. 2000 approximately (s).
However, the bodies of pipes smaller than nominal diameter No. 80 are
generally manufactured in reduced lengths and with special joints, On the
other hand, pipes of a nominal diameter greater than No. 1 O00 are only
just commencing to be manufactured centrifugally.
It has, therefore, appeared advantageous to limit the recommended range
so as to lie between nominal diameters No. 80 and No. 1000, as the extension of
(1) The water distribution pipelines follow the relief of the ground and the working pressure varies from
one point to another along their route. In practice it would be very dimcult to vary the thickness and con-
sequently the resistance of the castings according to their position in the pipeline and the pressure they have
to withstand, The resulting increase in the number of patterns would complicate both stocking and distribu-
tion, besides increasing the risk of errors on the construction site.
(a) In the tables, nominal diameter (DN) is only a number designating and classifying the dimensions of
pipes, specials and line parts.
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IUV, .\.Y - ."-- \-,
the recommendation to other nominal diameters at a later date does not present
any difficulty.
The external shapes and measurements of the sockets of the pipes and
specials vary slightly between the different countries.
However, this does not
cause difficulties, as the majority of these measurements are not bound up
with the interchangeability of the castings.
For reasons of safety, it has,
however, been considered necessary to prescribe the minimum thicknesses of
these sockets at the front and back (letters g and h, tables J 1 and J 2). The
external shape of specials will allow, according to the pattern adopted, a slight
projection at the joining of the socket and the barrel.
The problem is obviously the same for flanges the measurements of which,
in the various countries, showed differences of several millimetres. Without
wishing to bring in mathematical considerations, which are always difficult to
justify, it has been decided to adopt a range of average thicknesses which
follow a linear law in relation to the diameter. The measurements resulting
from this formula are intermediate between those existing in the different
countries. Interchangeability is thus ensured between the varying old flanges
and the new unified flanges.
As a rule, the latter are particularly strong, and they may be used on
socket mains at pressures up to 15 kg/cma approximately.
It is to be noted that the diameter of the holes is greater by 1 mm than
that provided for surface mains. This increase facilitates the installation of
the castings, which is always difficult in the case of underground mains, and
permits the use of bolts of increased diameter whenever this is thought neces-
sary in order to resist corrosion.
Comments on Section III - Pipes
Until 1939, pipes were manufactured in several thicknesses which cor-
responded respectively to different international series By A, LA. In each series
the thicknesses were fixed arbitrarily according to local custom and without
logical consideration. Most class B pipes of large diameter were not quite
thick enough. On the other hand, for medium diameters, the differences in
the thicknesses between the class A pipes and those of class LA were very slight
-in certain cases 1/2 mm only-which was clearly insufficient to justify the
coexistence of two different types.
One of the main purposes of this Recommendation is precisely to bring
about agreement between the thicknesses of the different pipe classes.
Class LA has been taken as a basis and its thicknesses have been de-
termined in a quite mathematical manner showing a linear relation to the
nominal diameter. These thicknesses are generally equivalent to those which
1939.
were applied in
Class A allows a 10 per cent increase in thickness over class LA for all
nominal diameters.
Class B allows a 20 per cent increase in thickness over class LA for all
nominal diameters. The thicknesses of class B for the nominal diameters
No. 100 to No, 350 inclusive are absolutely equal to those used before 1939.
Beyond the latter nominal diameter, the new series includes logically graded
thicknesses, slightly greater than those used previously.
For special uses, classes C, Dy E, etc. may be considered, allowing respective
increases of thicknesses of 30 per cent, 40 per cent, 50 per cent, etc. over
class LA.
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IS0 / R 13 - 1955 (E)
The weights have been calculated for each of the lengths generally used,
by taking into account in each case a socket weight, fixed arbitrarily as a pro-
portion of the weight of the pipe barrel.
For flanged pipes, only class B pipes with moulded flanges or screwed
flanges have been covered. In the latter case the method of screwing and the
exact form of the thread are left to the discretion of the manufacturer, in view
of the fact that the flanges are never removed after screwing on the barrels
,
of the pipes.
Comments on Section IV - Special castings
As a rule, the specials have been designed with the minimum possible
dimensions. Their ends are flanged or socketed (l).
As specials with spigot ends have less strength and precision, the standard
provides only for flange and spigot pieces and plugs.
O
The flange and socket and the flange and spigot specials (see tables T 10 and
T 11) are as short as possible so as to reduce the space required in underground
chambers, in which they are often placed.
The 1/4 bends (see tables T 13, T 30 and T 31) have been designed with
the radius of curvature adopted by the majority of countries.
The 1/8, 1/16 and 1/32 bends (see tables T 14, T 15, T 16 and T 32) have
been designed with the same radius for the central part, allowing the machin-
ing in series of the corresponding curved part of the different patterns.
Only the 1/8 flanged bends, up to a nominal diameter No. 300 (see table
T 32), have a different radius; this is dependent on the length prescribed for
the tangents and is in conformity with the practice in many countries.
The tees (see tables T 17, T 18 and T 33) of a nominal diameter smaller
as they
than No. 350 have been provided with a full range of branches,
are used chiefly in distribution mains for which branches down to a minimum
nominal diameter No. 80 may be taken off the main piping.
Mains of a nominal diameter greater than No. 300, however, are usually
trunk mains, either conducting or delivering, and are not generally used for taking
No. 300,
off branches for distribution pipes of small diameter. That is why, beyond
only tees with branches of a nominal diameter equal to, or greater than, half
the nominal diameter of the body, have been provided for.
Tees with very small branches of reduced lengths may be adopted sub-
sequently, after study of their statistics of use.
It is important to note that two different types have been retained for
each tee measurement, namely:
double socket tees with flanged branch (see table T 17),
double socket tees with socket branch (see table T 18).
(1) This preference for specials with sockets is justified by many advantages.
In a main, the position of the specials: bends, tees, etc., is nearly always governed by the lay-out of the
route and rarely coincides with the end of a pipe.
It is, therefore, necessary to interpose between the last whole pipe and the s ecial, a section of reduced
length obtained b cutting a whole pipe into two lengths. The first portion is usetbefore the special and the
second imrnediatery afterwards, one of these portions being without a socket. The all-socket specials provide
the missing socket, and, therefore, the construction of the pipe-line proceeds without any need of leaving out
lengths on the site.
Specials with two sockets, as compared with the other specials, have the following advantages:
mechanical resistance increased by the resence at each of their ends of a very strong socket,
excellent stability on anchorages, whit\ can extend over the whole length of the specials,
complete accessibility of joints which are clear of anchorages,
simplification of orders and of the supply of spares by the elimination of superfluous specials, many of
which have the same use.
facility of moulding on symmetrical plate patterns, in conditions favouring precision and production.
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ISO/ R 13 - 1955 (E)
The coexistence of these tho types constitutes a regrettable situation, as
the number of tee patterns is much greater than that of the other specials,
on account of the variations in the diameter of the branches.
The necessity for the two types is imposed by the methods of fitting
valves practised in different countries:
- in certain countries flanged valves, and consequently tees with flanged
branches, are used;
- in other countries, and particularly in American countries, socket
valves, and consequently tees with socket branches, are preferred.
It is, therefore, desirable, in order to achieve a reduction in the number
of types, that an international unification should take place by degrees for
the types of valves as well as of the tees.
Crosses (see tables T 19 and T 34) are provided for up to a nominal dia-
meter No. 300, with equal branches on the body: the adoption of castings
allowing reduced branches would be very disadvantageous, on account of the
many possible combinations of branches and of the very small number of
crosses used.
The double socket and double flanged tapers (see tables T 20 and T 35)
are as short as possible, so as to allow the use of several successive tapers, if
necessary.
The caps, plugs and blank flanges (see tables T 21, T 22 and T 36) have
been shown unreinforced; they can also be quite suitably manufactured with
domed ends, and they can have facing strips necessary for mounting the
standpipes and gauges.
*
* *
As a rule, all the measurements have been fixed, not arbitrarily, but in a
linear relation to the diameter.
This arrangement allows the grading of the measurements, as well as the
outlines of the castings, to be harmonized.
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IS0 / R 13 - 1955 (E)
SECTION I
TECHNICAL SPECIFICATION
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IS0 / R 13 - 1W (E)
SECTION I
TECHNICAL SPEC1 FICATION
Clause 1 - Scope
This Recommendation is applicable to :
1. cast iron pipes manufactured by any one of the three following processes :
(a) centrifugal casting in metal moulds,
(b) centrifugal casting in sand moulds,
(c) vertical casting in sand moulds;
8
2. cast iron special castings.
The Recommendation is applicable to pipes and all special castings with
sockets, spigots or flanges defined by this Recommendation and to pipes and
special castings with other types of joints, the general dimensions of which,
except those relating to the joints, conform to the requirements of this
Recommendation. It is not applicable to the down pipes and their specials
used in the building industry.
Clause 2 - Types of joints
Socket pipes and special castings for lead joints may be provided with
a centreing ring in the socket, and in this case, are supplied with a plain
spigot end. Alternatively, the sockets may be without centreing ring, in which
case the spigot ends could be plain or have a bead integrally cast or formed
by means of a permanent hoop shrunk on hot.
Q
Unless otherwise specified, flanges are machined on boss and their dimen-
sions are in accordance with the relevant tables in this Recommendation.
Bolt holes may be drilled or cored.
When pipes and special castings are ordered with a joint of a type other
than those mentioned in this Recommendation, the dimensions and other
characteristics of the joint are those applicable to that joint.
Clause 3 - Special castings
The special castings are of the thickness shown in the relevant tables,
Such
except when the working conditions necessitate some strengthening.
strengthening may be in the form of additional thickness, ribs, bolts, or other
means proposed by the manufacturer and finally approved by the purchaser.
If necessary, the reinforcement of the thickness may be obtained by
reducing the internal diameter.
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ISO/ R 13 - 1- (E)
Clause 4 - Marking
it the mark of the
Each pipe and special casting has cast or painted on
manufacturer, the nominal diameter and, if necessary, its principal char-
acteristics.
The marks are placed:
(a) on the socket faces of pipes centrifugally cast in metal moulds;
(b) on the outsides of the sockets or on the barrels of pipes centri-
fugally cast in sand moulds;
(c) on the outsides of the sockets or towards the ends of the barrels
of pipes vertically cast in sand moulds;
(d) on the barrels of special castings.
The class or any other marks required by the purchaser may be painted on.
Clause 5 - Quality of metal used
The metal used for the manufacture of pipes and special castings should
be of good quality. It is prepared at the discretion of the manufacturer in
a cupola, an active mixer, or other suitable furnace, and is made from pig
iron, or molten iron, or good iron and steel scrap with additions of good quality
materials suited to the production method, excluding any raw material of inferior
quality. Upon fracture, the iron should show a grey, close and uniform grain.
Clause 6 - Quality of pipes and special oastings
Pipes and special castings are stripped with all precautions necessary to
avoid warping or shrinking defects detrimental to their good quality.
The pipes and special castings should be sound and free from surface or
other defects.
Repairing of defects by soldering or by the application of putty may not
be done without previously securing the consent of the purchaser or his
representative. This stipulation also applies to the plugging of leaks by
caulking.
Pipes and special castings showing small imperfections inseparable from
the method of manufacture and not affecting their use, are not rejected.
The pipes and special castings should be such that they can be cut, drilled
or machined; in case of dispute, the castings are considered as acceptable,
provided the hardness, measured at the centre of the thickness, does not exceed
the Brinell number 215. The superficial hardness of pipes centrifugally cast
in metal moulds does not exceed the Brinell number 230 (for hardness test,
see clause 14).
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ISO/Rl3 - l%5 (E)
I
Clause 7 - Tolerances on the external diameter of the barrel,
the internal diameter of the socket,
and the depth of the socket
The socket tolerances are as follows (where DN is the nominal diameter of the
pipes and special castings in millimetres, fis the caulking space of the joint in
millimetres and equal to f = 9 + 0.003 DN):
Dimenslon Nominal diameter
Tolerance in millimetres
External diameter
All diameters f 1/2 f = f (4.5 +0.0015 DN)
of barrel DE
Internal diameter
All diameters
f 1/3f = f (3 +O.OOl DN)
of socket DI
Up to and including
rt5
No. 600
Depth of socket P
Over No. 600 and up to
and including No. 1000
The maximum or minimum jointing space resulting from these tolerances
is such that the jointing of the pipes and special castings is not adversely
affected.
Clause 8 - Tolerances on thickness
The tolerances on the wall thickness and flange thickness are limited as
follows, where I
is the standard thickness of the wall in millimetres, and
e
b is the standard thickness of the flange in millimetres:
Tolerance in millimetres
Dimension
Type of casting
Wall thickness - (1 + 0.05 e) *
Pipes
f (2 + 0.05 b)
Flange thickness
- (2 + 0.05 e) *
Wall thickness
Special castings
Flange thickness f (3 + 0.05 b)
* No limit for the plus tolerances has been set (see clause 11, Note).
The thickness of special castings may exceptionally be reduced to not less
than the minimum thickness of class B pipes of the same diameter, provided
that the area of the affected part is not more than l/lOth of the cross-sectional
area of the bore.
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ISO/Rlt - 1955 (E)
Clause 9 - Tolerances on length
The tolerances on normally manufactured lengths of pipes and special
castings are as follows:
Tolerance In
Type of casting Nominal diameter
millimetres
Socket and spigot and
All diameters
plain ended pipes
I f20 I
Up to and including No. 450
Socket special castings, f 20
flange and socket and
flange and spigot pieces Over No. 450 + 20
- 30
Flanged pipes and
All diameters
flanged special castings
I &lo I
Should smaller tolerances be demanded, for example in the case of flanged
closing pieces, they are specially fixed, but the minimum tolerance may not
be less than f 1 mm.
Of the total number of socket and spigot pipes to be supplied in each
diameter, the manufacturer may supply up to 10 per cent in lengths shorter
than specified as follows:
Specieed length Decrease In length
I l
~~ ~~
- -
4m 0.5 m lm
Over 4 m 1 0.5m 1 lm 1 1.5m 1 2m
Clause 10 - Permissible deviation from a straight line
The pipes should be straight. When rolled along two gantries separated
by approximately two-thirds the length of the pipe to be checked, the maximum
deviation fm, in millimetres, should not be greater than 1.25 times the length I
in metres of this pipe, thus fm L 1.25 1.
Clause 11 - Tolerances on weight
The standard weights are those shown in the attached tables or, for rein-
forced or non-standard special castings, those calculated by taking the specific
weight of cast iron as 7.15 kg/dm*.
The tolerances on standard weight are as follows:
I I I
Type of casting I Tolerance
I
I
I
I I I
Pipes f 5%
Special castings except as stated below f 8%
Bends, special castings with more than one branch
f 12%
and non-standard special castings
I J
I
Note. - Castings of a heavier weight than the maximum are accepted, provided
they comply in every other respect With the requirements of this Recommendatlon.
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ISO/Rl3 - 1855 (E)
Clause 12 - Mechanical tests
(a) For pipes centrifugally cast in metal moulds
Tests are made:
(a) on rings for pipes up to and including the nominal diameter
No. 300,
(b) on tensile bars for pipes over the nominal diameter No. 300.
The rings and bars are cut from the spigot end of the pipes.
(b) For pipes centrifugally cast in sand moulds
Tensile tests are made on bars for pipes of all nominal diameters.
The bars are cut from the spigot end of the pipes.
(c) For pipes vertically cast in sand moulds and special castings
Tensile tests are made, for pipes and special castings of all nominal dia-
meters, on bars cast from the same metal as is used in the castings.
Ring tests for pipes centrifugally cast in metal moulds (fig. 1)
Rings of approximately 25 mm width are tested on a suitable machine.
The rings are supported on two knife edges diametrically opposed and the load
is applied from the i
...