GOST R ISO 2531-2008

• gost-r-iso-2531-2008.pdf (1.16 MiB)
  ГОСТ Р ИСО 2531-2008

GOST R ISO 2531−2008 Pipes, fittings, fittings and their joints of spheroidal graphite cast iron for water and gas. Specifications

GOST R ISO 2531−2008

Group В62

NATIONAL STANDARD OF THE RUSSIAN FEDERATION

PIPES, FITTINGS, FITTINGS AND THEIR JOINTS OF SPHEROIDAL GRAPHITE CAST IRON FOR WATER AND GAS

Specifications

Ductile iron pipes, fittings, accessories and their joints for water or gas applications. Specifications

OKS 23.040.10
GST 14 6000

Date of introduction 2010−01−01

Preface

The objectives and principles of standardization in the Russian Federation established by the Federal law of 27 December 2002 N 184-FZ «On technical regulation», and rules for the application of national standards of the Russian Federation — GOST R 1.0−2004"Standardization in the Russian Federation. The main provisions"

Data on standard

1 PREPARED by the Technical Committee for standardization TC 357 «Steel and cast iron pipes and cylinders» and Open joint stock company «Russian scientific research Institute of pipe industry» (JSC «RosNITI») based on the authentic translation of the standard referred to in paragraph 4, which is FSUE «STANDARTINFORM"

2 SUBMITTED by the Technical Committee for standardization TC 357 «Steel and cast iron pipes and cylinders"

3 APPROVED AND put INTO EFFECT by the Federal Agency for technical regulation and Metrology dated December 25, 2008 N 662-St

4 this standard is identical to international standard ISO 2531:1998 «Pipes, fittings, fittings and their joints of spheroidal graphite cast iron for water and gas» (ISO 2531:1998 «Ductile iron pipes, fittings, accessories and their joints for water or gas applications»)

The name of this standard changed with respect to names specified international standard for compliance with GOST R 1.5−2004 (subsection 3.5)

5 INTRODUCED FOR THE FIRST TIME


Information about the changes to this standard is published in the annually issued reference index «National standards», and the text changes and amendments — in monthly indexes published information «National standards». In case of revision (replacement) or cancellation of this standard a notification will be published in a monthly information index «National standards». Relevant information, notification and lyrics are also posted in the information system of General use — on the official website of the Federal Agency for technical regulation and Metrology on the Internet

1 Scope

This standard specifies the requirements and test methods for pipes and fittings made of cast iron with nodular graphite and compounds used for manufacturing pipeline:

— for transportation of water (e.g. drinking water) or gas (e.g. natural);

— working under pressure or without pressure;

— laid underground or above ground.

Note — In this standard, the pressure is a relative pressure expressed in Pascals.


This standard includes technical requirements for materials, dimensions and tolerances, mechanical properties and standard coatings of pipes and fittings.

This standard applies to cast iron pipes and fittings cast by any method, foundry or fabricated from cast parts, and corresponding compounds with a diameter from 40 to 2600 mm, inclusive.

This standard is applicable to pipes and fittings that are:

— made with a flanged or bell-and-spigot ends for connection by means of seals of different types (seals are not considered in this standard);

— usually come with inner and outer coatings.

2 Normative references

________________

* All reference to international standards other than ISO 6506−1:2005, relevant national standards do not exist. Prior to approval, it is recommended to use the translation into Russian language of these international and regional standards. Translations of the standards are the Foundation of technical regulations and standards of JSC «Russian scientific research Institute of pipe industry» (JSC «RosNITI»).

This standard uses the regulatory references to the following standards:

ISO 4179:1985 Pipe from spheroidal graphite cast irons for pressure and non-pressure pipelines. Lining of cement mortar applied by centrifugation. General requirements

ISO 4633:1996 rubber Seals. O-rings for the supply, drainage and Sewerage pipelines. Technical specifications for materials

ISO 6447:1983 rubber Seals. O-rings for gas pipes and fittings. Technical specifications for materials

ISO 6506−1:2005* metal Materials. The hardness test. Hardness Brinell

________________

* ISO 6506−1:2005 complies with the RF national standard GOST 9012−59 (ISO 410−82, ISO 6506−81) «Metals. A method of measuring the hardness of Brinell».

ISO 7005−2:1998 metal Flanges. Part 2. Flanges of cast iron

ISO 7268:1983 pipe Elements. The definition of nominal pressure (with amendment 1:1984)

ISO 7483:1991 Dimensions of gaskets used with flanges according to ISO 7005

ISO 8179−1:2004 Pipe from spheroidal graphite cast irons. Outer zinc coating. Part 1. Coating of metallic zinc with finishing layer

ISO 8179−2:1995 Pipe from spheroidal graphite cast irons. Outer coating. Part 2. Coating with paint with a high content of zinc dust and the finishing layer

ISO 8180:1985 Pipe from spheroidal graphite cast irons. Plastic clutch

ISO 10804−1:1996 fixed connections for pipes made of cast iron with nodular graphite. Part 1. Design rules and standardized testing

YONG 1092−2:1997 Circular flanges for pipes, valves, fittings, and valves, are designed for a nominal pressure (). Part 2. Flanges of cast iron

3 Terms and definitions

This standard applies the following terms with respective definitions:

3.1 high strength cast iron with nodular graphite (ductile iron): the Type of cast iron in which graphite is present primarily in spheroidal form.

3.2 pipe (pipe): Casting with a uniform channel, with direct axis, having a tapered, covered or flanged ends.

3.3 fitting* (connecting part): Attached to the steel casting, which ensures the deviation, change of direction of the pipeline or channel. Fittings, except stop and safety are the connecting parts. Pipe fittings are elements of the pipeline.

________________

* A term adopted by the international standards.

3.4 flange (flange): round end Flat tubes or connecting part, perpendicular to their axis, with bolt holes, evenly spaced around the circumference.

Note the Flange on the pipe can be fixed or be adjustable; an adjustable flange comprises a ring attached by bolts at one or more locations, which carries the load on the end of the splice sleeves and can rotate freely around the axis of the pipe to the connection.

3.5 narrow sleeve; the clutch (collar; coupling): coupling piece used for coupling together the male ends of the pipes or fittings.

3.6 the smooth end (spigot): the End of the pipe or fittings to be placed into the flare.

3.7 the socket (socket): the End of the pipe or the fitting, covering the smooth pipe end or fitting.

3.8 gasket (gasket): the Sealing element of the connection.

3.9 the connection (joint): a Connection between ends of pipes and/or fittings in which a gasket is used as seal.

3.10 flexible joint (flexible joint): a Compound which provides a significant angular misalignment and parallel or perpendicular movement relative to the axis of the pipe.

3.11 socket flexible joint (socket flexible joint): a Flexible coupling is assembled by means of the push the smooth end through the gasket into the bell of the paired element.

3.12 flexible mechanical connection (mechanical joint flexible): a Flexible coupling in which the seal is provided by pressure to the gasket by mechanical means, such as seal.

3.13 fixed connection (restrained joint): a Connection which provides means preventing separation of the assembled joint.

3.14 flanged (flanged joint): a Connection between two flanged ends.

3.15 nominal size (nominal size): Conditional pass diameter of the pipe, which is common to all elements of the pipeline system.

3.16 nominal pressure (nominal pressure): numerical designation expressed by a number having an informational character. All elements of the same nominal size, marked with the same number rated pressure, have compatible mating dimensions (ISO 7268).

3.17 allowable working pressure (allowable operating pressure): Internal pressure, excluding pressure surges, which element (pipe, fittings, valves and their connections) can safely withstand in permanent work.

3.18 maximum allowable working pressure (allowable maximum operating pressure): Maximum internal pressure, including pressure surges, which element can safely withstand during operation.

3.19 allowable test pressure (allowable test pressure): Maximum hydrostatic pressure that a member can withstand for a relatively short period of time, intended to determine the integrity and tightness of the pipeline.

Note — Currently test pressure differs from the test pressure in the system, which refers to the design pressure of the pipeline and is designed to ensure its integrity and tightness.

3.20 diametral stiffness of a pipe (diametral stiffness of a pipe): the pipe Feature, which provides resistance to the diametrical deflection under load.

3.21 batch (batch): the Number of items from which to choose a sample for testing in the production process.

3.22 type test (type test): a Test for compliance of a design which is carried out once and is repeated only after change of design.

3.23 length (length): the Actual length of the pipe or the fitting which is shown in the drawings of section 8.

Note — For flanged pipes or fittings effective length (for pipes) of equal length. For socket fusion of pipes and fittings effective length (for pipes) is equal to total length minus the depth to which part of the covered end as specified in the manufacturer catalogs.

3.24 deviation (deviation): the value by which the design length may differ from the standard length of pipe or a fitting.

Note — the Pipes and fittings are designed accordingly in length selected from a range of standard lengths, plus or minus the deviation (table 4); they are manufactured to this length plus or minus the tolerance specified in table 5.

3.25 out-of-roundness (ovality), %: the Deviation from the circumference of the pipe cross section.

, (1)

where  — the maximum external diameter, mm;

 — the minimum external diameter, mm;

 — nominal external diameter, mm.

4 Technical requirements

4.1 General provisions

4.1.1 Pipe and fittings

Nominal diameter, nominal wall thickness, length and coverage defined in this paragraph, 4.2.2, 4.2.3, 4.4 and 4.5 respectively. If by agreement between the manufacturer and the customer supply pipe and fittings under this standard, different design, different size, different thickness and different finish than specified in 8.3 and 8.4, the pipes and fittings must comply with all other requirements of this standard.

Nominal dimensions (in) pipe and fittings shall be the following: 40, 50, 60, 65, 80, 100, 125, 150, 200, 250, 300, 350, 400, 450, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1400, 1500, 1600, 1800, 2000, 2200, 2400, 2600 mm.

Functional properties (stiffness of the pipe and diametrically deflection) of pipes from spheroidal graphite cast irons specified in Annex C.

Allowable working pressure maximum allowable working pressure and allowable test pressure (3.17, 3.18 and 3.19) are specified in national standards.

Note — When the pipes and fittings of ductile iron installed and operating under conditions for which they are designed (appendices A and b), they retain all the performance characteristics during the service life, due to constant material properties, stability, cross sections, and their design with high safety factor.

4.1.2 surface Condition

Pipe and fittings shall not have defects and surface damage, which could impair their compliance with the requirements of sections 4 and 5.

4.1.3 Types of pipe connections

4.1.3.1 General provisions

Joints design and shape of the pads are not objects of this standard.

Materials rubber gaskets shall conform to the requirements of ISO 4633 for water and ISO 6447 — for gas supply. When required nerezinovoy materials (e.g. flange connections), they must meet the requirements of the relevant standards.

4.1.3.2 Flanged connections

Dimensions and tolerances for flanges of pipes and fittings shall comply with ISO 7005−2 or EN 1092−2, flange gaskets, ISO 7483. This provides a connection between flanged elements (pipes, fittings, valves, etc.) of the same nominal diameter and nominal pressure corresponding to operational characteristics of connections.

Although this does not affect the connecting piping systems, the manufacturer shall specify in its catalog, supplied products with solid or loose flanges.

4.1.3.3 Flexible joints

The outer diameters of smooth pipe ends and fittings with flexible joints and their tolerances shall conform to the requirements of 4.2.1.1. This provides the possibility of connection elements provided with flexible connectors of various types. Moreover, the flexible connection of all types must comply with the performance requirements of 5.2.

Notes

1 For connecting different types of elements that operate in a narrow range of tolerances of the outer diameter, the manufacturer’s instructions should be used as a means of ensuring adequate operation of the connection even at the highest pressures (e.g. measurement and selection of external diameter).

2 For connections to existing pipelines, which may have outer diameters that are not relevant to 4.2.1.1, manufacturer’s instructions can be used to recommend appropriate means of connection (e.g. adapters).

4.1.3.4 Fixed connection

Fixed connections for high strength pipelines of ductile iron shall be designed in accordance with ISO 10804−1. The outer diameters of smooth finishes and tolerances on them shall conform 4.2.1.1.

4.1.4 Materials in contact with drinking water

If the pipes made of spheroidal cast iron and fittings used in the conditions for which they were designed, in permanent or temporary contact with drinking water, they should not adversely affect the properties of water.

Note where appropriate, you must refer to standards or other normative documents concerning the influence of materials on water quality.

4.2 size Requirements

4.2.1 Diameter

4.2.1.1 Outer diameter

In table 11 (8.1) indicates the value of the outer diameter of the smooth pipe ends or fittings, measured along the circumference of the circular measuring tape in accordance with 6.1.1. The positive tolerance is +1 mm and applies to all thickness classes of pipes and flanged fittings with plain end.

Negative tolerance depends on the design of each connection type should be as specified in the manufacturer catalogs for the type of connection and the nominal diameter.

In addition, the ovality (3.25) smooth-end pipes and fittings shall:

to stay within the tolerances of the outer diameter for nominal diameters from 40 to 200 mm;

— be not more than 1% of the outer diameter for nominal diameters from 250 to 600 mm or not more than 2% of the nominal diameter more than 600 mm.

Note — manufacturer should specify the means of correcting ovality that is necessary; some flexible joints can allow the maximum ovality without the need for re-rounding the covered end before attaching.

4.2.1.2 Inner diameter

The nominal value of the internal diameter centrifugal cast iron pipe, expressed in millimeters, approximately equal to the value of the nominal diameter.

4.2.2 wall Thickness

Nominal wall thickness of cast iron pipes and fittings should be calculated according to the following formula, the thickness of the wall shall not be less than 6 mm for centrifugal cast iron pipes and 7 mm for cast iron pipe, cast in a different way, and connecting parts

, (2)

where is the nominal wall thickness, mm;

 — factor to denote the class of wall thickness. He is chosen from the series of integers: 7, 8, 9, 10, 11, 12…;

 — nominal diameter, mm.

Standard classes of wall thickness for tubes is given in 8.1 and 8.2; by agreement between the manufacturer and the consumer possible other thickness of the pipe wall.

For fittings the wall thickness , is given in 8.3 and 8.4, is the nominal thickness corresponding to the main body portion. The actual thickness at any point may be increased when necessary to maintain a local high voltage, depending on the size and shape of the casting (e.g. within the inner radius of the knees, within the joints of the exhaust tee, etc.).

The tolerances on nominal wall thickness of pipes and fittings shall be as specified in table 1. Measurement of pipe wall thickness should be as specified in 6.1.2.

Table 1 — Tolerance on nominal wall thickness

In millimeters

Type casting	Wall thickness	Tolerance*
Centrifugal cast ductile iron pipe	6	-1,3
	>6	-(1,3+0,001)
Pipe, cast in a different way, and fittings	7	-2,3
	>7	-(2,3+0,001)
* Negative tolerance is specified only in order to provide sufficient resistance to internal pressure.

4.2.3 Length

4.2.3.1 Length tapered pipes and tubes with smooth ends

Pipes shall be supplied in accordance with the length values shown in the table 2.

Table 2 — Standard length pipes

Nominal diameter , mm	Standard length * m
40 and 50	Of 3.00
From 60 to 600 incl.	4,00; 5,00; 5,50; 6,00; 9,00
700 and 800	4,00; 5,50; 6,00; 7,00; 9,00
From 900 to 2600 incl.	4,00; 5,00; 5,50; 6,00; 7,00; 8,15; 9,00
* See 3.23.

Project length (3.23) must be within the specified standard values of the length of ±250 mm (table 2) and should be listed in the directories. The actual length should be measured according to 6.1.3 and shall not vary from design length by more than the tolerance specified in table 5.

The total number of supplied pipes with a socket and pipes with smooth ends of each diameter, the percentage of short pipes should not exceed 10%.

Notes

1 Pipe, cut for testing, may be excluded from the 10% and considered as tubes of full length.

2 When pipe is ordered by the meter, the manufacturer can determine the required number of supply pipes by summing the actual lengths of the tubes measured individually.

4.2.3.2 Length flanged pipe

Lengths flanged pipes indicated in table 3. By agreement between the manufacturer and the customer allowed other lengths.

Table 3 — Length flanged pipe

The type of pipe	Nominal diameter, mm	Standard length * m
Cast with flanges	From 40 to 2600 incl.	0,5; 1,0; 2,0; 3,0
With provernutye or welded flanges	From 40 to 600 incl.	2,0; 3,0; 4,0; 5,0
	«700» 1000"	2,0; 3,0; 4,0; 5,0; 6,0
	«1100» 2600 «	4,0; 5,0; 6,0; 7,0
* See 3.23.

4.2.3.3 length of the connecting parts

Fittings shall be supplied respectively to the lengths specified in 8.3 and 8.4.

Note — there are two series of dimensions — series a and new series In, generally limited to 450 mm.


Permissible deviation (3.24) of the length of the connecting parts of the series And shall be as specified in table 4.

Table 4 — Deviation of the length of the connecting parts

In millimeters

Type fittings	Nominal diameter	Deviation
Flanged sockets A flange covered by the ends Narrow sleeve	From 40 to 1200 incl.	±25
	From 1400 to 2600 incl.	±35
Tees	From 40 to 1200 incl.	+50 -25
	From 1400 to 2600 incl.	+75 -35
90° bend (¼)	From 40 to 2600 incl.	±(15+0,03)
Elbows 45° (1/8)	From 40 to 2600 incl.	±(10+0,025)
Knee 22°30' (1/16) and 11°15' (1/32)	From 40 to 1200 incl.	±(10+0,02)
	«1400» 2600 «	±(10+0,025)

4.2.3.4 the Tolerance on the length

Tolerances on length shall be as specified in table 5.


Table 5 — Tolerances on length

In millimeters

Type casting	Tolerance
Bell-and-spigot pipe and pipe with smooth ends (full length or cropped)	±30
Connecting parts for flare connections	±20
Pipes and fittings for flanged joints	±10*
* By agreement between the manufacturer and the consumer of possible smaller tolerances, but not less than ±3 mm for 600 mm and not less than ±4 mm for 600 mm.

4.2.4 Curvature of tubes

Pipe must be straight with a maximum deviation of 0,125% of their length.

Verification of this requirement is carried out visually, but if in doubt or in case of doubt, the deviation (curvature) can be measured in accordance with 6.2.

4.3 material Characteristics

4.3.1 tensile Strength

Pipes and fittings made of spheroidal graphite cast iron must have a tensile strength specified in table 6.

Table 6 — Mechanical properties of cast iron products

Type casting	Tensile strength tensile , MPa, not less	The percentage elongation after rupture , %, not less
	from 40 to 2600 mm	from 40 to 1000 mm	from 1100 to 2600 mm
Centrifugal cast pipe	420	10	7
Pipe, cast in a different way, and fittings	420	5	5
Notes 1 by agreement between the manufacturer and user can be specified yield strength in tolerance of not less than 0.2%. It needs to be no less than: 270 MPa when 12% from 40 to 1000 mm or 10% for 1000 mm; not less than 300 MPa in other cases. 2 For centrifugal cast iron pipes from 40 mm to 1000 mm the minimum elongation after fracture shall be not less than 7% for the classes of wall thickness more than 12.

During the manufacturing process, the manufacturer can conduct the appropriate tests to verify the tensile strength. These tests can be applied:

— sampling method of the batch in which the samples are taken from the covered part of the pipe or for fittings, from samples cast separately or as a whole with the corresponding casting. The samples should be taken from the lot prepared by machining and tensile tested according to 6.3;

test method for control of a technological process (for example nondestructive testing), when positive correlations indicate mechanical properties in tension specified in table 6. The verification procedure is to compare comparable samples with certain properties. This test method must be confirmed by a tensile test according to 6.3.

4.3.2 Brinell Hardness number

Various elements should be so solid that they can be cut, tapped, drilled and/or machined with standard tools. In case of dispute, the hardness shall be measured according to 6.4.

Hardness on the Brinell hardness shall not exceed 230 HB for centrifugal cast iron pipes and 250 HB for cast iron pipes, cast another way, and connecting parts. For items manufactured by welding, the high hardness acceptable in the heat zone of the weld.

4.4 pipe Coating

Supply pipe should have an outer and inner coating.

4.4.1 External coatings

Depending on the external operating conditions (Appendix A) and in accordance with the regulations, you can use the following exterior coatings:

— metallic zinc with finishing layer in accordance with ISO 8179−1;

paint with a high content of zinc dust with finishing layer ISO 8179−2;

— a thicker coating of metallic zinc with finishing layer;

— polyurethane;

— polyethylene;

— fiber-cement solution;

— adhesive tapes;

bituminous paint;

— epoxy resin.

4.4.2 Internal coating

Depending on internal conditions (Annex b) and in accordance with the regulations, you can use the following internal coating:

— a solution of Portland cement (with additives or without additives) in accordance with ISO 4179;

— a solution of aluminous cement according to ISO 4179;

solution of slag Portland cement according to ISO 4179;

— cement mortar with insulating layer;

— polyurethane;

— polyethylene;

— epoxy resin;

— bitumen paint.

4.5 Coating of fittings

Supply the fitting shall have external and internal coatings.

4.5.1 Outer coating

Depending on the external operating conditions (Appendix A) and in accordance with the regulations, you can use the following exterior coatings:

— bitumen paint or a paint based on synthetic resins;

— epoxy resin;

zinc with finishing layer;

plastic coupling according to ISO 8180;

— polyurethane;

— adhesive tapes.

4.5.2 Internal coating

Depending on internal conditions (Annex b) and in accordance with the regulations, you can use the following internal coating:

bituminous paint or paint based on synthetic resins;

— a solution of Portland cement (with additives or without additives);

— a solution of aluminous cement;

— a solution of slag cement;

— cement mortar with insulating layer;

— polyurethane;

— polyethylene;

— epoxy resin.

4.6 Marking

All pipes and fittings should have stable and clearly marked, including:

— name or trademark of the manufacturer;

the notation of the year of manufacture;

— designation of the material (nodular cast iron);

— nominal diameter;

— nominal pressure of flanges in use;

— the designation of this standard;

— marking of pipes, which were tested for gas.

The first five marks shall be cast or applied by cold stamping. The last two designations applied by any method, for example in the casting, or applied to the label, which is fixed on the package.

5 Requirements of integrity

5.1 Pipe and fittings

Pipe and fittings shall be designed so as to be sealed at the allowable test pressure. They should be 6.5 or 6.6, however, they must not have visible leakage, exudation or any other signs of damage.

5.2 Flexible joints

5.2.1 General provisions

All flexible connections of piping components of ductile iron components should be designed in accordance with the requirements of this subsection. If the design passed the test, the results of which are recorded by the manufacturer in a quality document and then successfully been used for at least ten years, then testing in accordance with 5.2.2 for internal pressure and 5.2.3 for external pressure is carried out only when significant design changes that can adversely affect the performance of the connection.

The design of the joint must pass a type test to confirm tightness under internal and external pressures in the most extreme values of the tolerances on the casting.

Routine tests should be carried out at least one for each of the groups of nominal diameters, specified in table 7. One nominal diameter represents a group when the characteristics are based on the same design parameters for the entire size range.


Table 7 — Preferred nominal diameters for testing for leaks

In millimeters

A group of nominal diameters	From 40 to 250 incl.	From 300 to 600 incl.	From 700 to 1000 incl.	From 1100 to 2000 incl.	From 2200 to 2600 incl.
The preferred nominal diameter for each group	200	400	800	1600	2400

If the groups are products of different designs and/or manufactured by different processes, they must be separated.

Note — If the group includes only one nominal diameter, that nominal diameter can be considered as a part of an adjacent group in the event if it is the same design and manufactured by the same process.


The model tests carried out at the maximum radial gap between the connecting elements (the smallest diameter of the smooth ends together with the wide socket).

In the model test, the maximum gap is equal to the maximum radial gap with a tolerance of plus 0% and minus 5%. The inner diameter of the socket may be machined to provide this clearance, even if the diameter deviates from a predetermined value.

Short flexible connections shall be designed and tested according to ISO 10804−1.

5.2.2 Internal pressure

Connections must pass standard test for resistance to internal pressure at 7.1 at the test pressure, which shall not be less than the stated allowable test pressure; the connection must not have visible leakage at the following positions:

— coupling ensures the alignment of the elements and exposed to lateral forces, while the shear force should be not less than 30and expressed in Newtons;

connection bend, the test angular deflection shall be the maximum allowable deflection indicated in the catalog of the manufacturer, but not less than 3° for 40 to 300 mm, 2° — from 350 to 600 mm, 1 ° — from 700 to 2600 mm.

5.2.3 External pressure

Connections must pass standard test for resistance to external pressure in 7.2; the joints shall not have visible leakage under the action of a lateral load equal to 30and expressed in Newtons.

The test pressure shall be not less than 100 kPa.

6 test Methods

6.1 Dimensions

6.1.1 Outer diameter

The diameter of the pipes with sockets and covered by the ends must be measured from the covered end of the circular measuring tape due to the tolerances on the outer diameter. They can also check with calibre for outdoor measurements.

In addition, pipes must be visually checked from the covered end due to the tolerances on ovality, and in case of doubt, by measuring the maximum and minimum diameters. This test can be carried out with the use of calibers for outdoor measurements.

Frequency of testing depends on the production and quality control used by the manufacturer.

6.1.2 wall Thickness

The matching of pipe wall thickness certain standards must be confirmed by the manufacturer; it may be a combination of various means such as:

— weight control pipe;

— direct measurement of wall thickness appropriate mechanical or ultrasonic instrument.

Frequency of testing depends on the production and quality control used by the manufacturer.

6.1.3 Length

Length centrifugal cast iron pipes with socket and cover ends should be measured with the appropriate tool:

— on the first pipe cast from a new mould, the measuring tubes full length;

at first cutting the pipe to measure systematically cut pipe, respectively, the preload length.

6.2 the Curvature of the pipe

The tube shall be rolled on two supports or rotated around its axis on the rollers, the distance between which in each case is not less than 2/3 of the standard length of the pipe.

Must have point of maximum deviation from the real axis, and the deviation measured at that point shall not exceed the limit specified in 4.2.4.

6.3 the tensile Test

6.3.1 Selection of samples

The thickness and diameter of the test piece shall be as specified in table 8.

Table 8 — section Dimensions of the test piece

Type casting	Test sample. Method And	Test sample. Method In
	Nominal diameter, mm	Nominal area mm	Nominal diameter, mm	Diameter tolerance, mm
Centrifugal cast pipe wall thickness, mm:
to 6	2,5	5	2,52	±0,01
6 to 8	3,5	10	3,57	±0,02
«8» 12	5,0	20	5,05	±0,02
«12	6,0	30	6,18	±0,03
Pipe, cast in a different way, and connecting parts:
the samples are molded as one unit	5,0	20	5,05	±0,02
private casting size, mm:
12.5 for specimens with thickness up to 12 mm	6,0	30	6,18	±0,03
25 for samples with thickness of 12 mm	12.0 or 14.0 per	-	-	-

6.3.1.1 Centrifugal cast ductile iron pipe

The sample should be cut from the male end of the pipe. This sample can be cut parallel or perpendicular to the axis of the pipe, but in case of dispute needs to be used the sample cut parallel to the axis.

6.3.1.2 Pipe, cast otherwise, and fittings

Samples should be taken at the discretion of the manufacturer from the sample, cast as a single unit, from the sample, connected to the casting or from a sample cast separately. In the latter case it must be cast from the same metal used for casting. If the casting is hot treatment, the sample shall be the same hot treatment.

6.3.2 Test sample

The test sample shall be manufactured by machining from each sample to represent the metal, taken from its mid-thickness; the diameters of the cylindrical part correspond to the values specified in table 8.

The base length of the test specimens shall be not less than five nominal pipe diameters of the test piece. The ends of the test pieces shall be suitable for installation of the specimen in the testing machine.

The surface roughness of the test piece of the base length should be not more than 6.3 µm.

At the manufacturer’s discretion may be used two method of measuring tensile strength:

— method b: produce the test sample with a nominal diameter ±10%, measure the true diameter before the test with an accuracy of ±0,01 mm and use measured diameter to calculate the cross sectional area and tensile strength;

method: produce a test sample nominal area with established tolerance on diameter (table 8) and use the nominal area to calculate the tensile strength.

6.3.3 Equipment and test method

Testing machine the gap must have suitable holders or grips for fastening the ends of the test piece so that the right to transfer the axial test load.

The loading rate needs to be constant and to be in the range of 6−30 N/(mm·s).

Tensile strength shall be calculated by dividing the maximum force acting on the test sample, the cross-sectional area of the test sample taking into account the ratio of extended length to base true base length. The elongation can be measured by the extensometer.

6.3.4 test Results

The results shall conform to table 6. If they do not match, the manufacturer shall:

a) in the case when the metal reaches the required mechanical properties, investigate the reason and ensure that all the castings of the party were re-heat treated or has been rejected; castings which have passed a second heat treatment, should be retested in tension;

b) in the case of a defect of the test sample to conduct additional testing. If it succeeds, the party and take; if not, the manufacturer may proceed in accordance with the listing).

Note — the Manufacturer may reduce the number of defective products, performing additional tests during production, limiting the rejected batch of castings before and after testing showing positive results.

6.3.5 Frequency of testing

Frequency of testing is related to the nature of production and the method of quality control used by the manufacturer (4.3.1). Maximum lot sizes should conform to table 9.

Table 9 — Maximum lot size

Type casting	Nominal diameter, mm	The maximum lot size of pipes.
		in selective control of the party	when testing for process control
Centrifugal cast ductile iron pipe	From 40 to 300 incl.	200	1200
	«350» 600 «	100	600
	«700» 1000 «	50	300
	«1100» 2600 «	25	150
Pipe, cast in a different way, and fittings	All sizes	4	48

6.4 Testing for hardness

When hardness Brinell (4.3.2) tests shall be conducted on the questionable casting or sample cut from a casting. The test surface must be properly prepared by lightly grinding the local, and the test shall be conducted in accordance with ISO 6506−1, using a steel ball with a diameter of 2.5 or 5, or 10 mm.

6.5 leak Testing of pipes and fittings for water supply

6.5.1 General provisions

Pipes and fittings should be tested on 6.5.2 and 6.5.3, respectively. Tests shall be conducted on all piping and connecting parts before coating them with external and internal coatings except zinc coating of pipes which may be applied before testing.

Test instruments shall be provided using established test pressure for pipes and/or fittings. They should be equipped with pressure gauges with the accuracy of measurements not less ±3%.

6.5.2 Centrifugal cast ductile iron pipe

Centrifugal cast ductile iron pipe is subjected to a hydrostatic test under the operating conditions of at least 10 with a minimum internal test pressure specified in table 10.


Table 10 — Minimum value of the test pressure

Nominal diameter, mm	The minimum value of the test pressure at operating conditions, MPa
	Centrifugal cast ductile iron pipe		Cast iron pipe, cast the other way*
	***<9	***9	All classes in thickness
From 40 to 300 incl.	0,05	5,0	2,5**
«350» 600 «	0,05	4,0	1,6
«700» 1000 «	0,05	3,2	1,0
«1100» 2000 «	0,05	2,5	1,0
«2200» 2600 «	0,05	1,8	1,0
* Hydrostatic test pressure for fittings is less than for pipes because the shape of fittings complicates the provision of sufficient constraints for high internal pressures during the test. ** 1.6 MPa for flanged pipes and fittings of 1.0. ***  — coefficient to denote the class of wall thickness.

6.5.3 cast Iron pipes and fittings, cast otherwise

At the choice of the manufacturer of cast iron pipes and fittings shall be subjected to a hydrostatic test pressure or test with compressed air, or any other similar test for leaks.

If the hydrostatic test pressure must be exactly the same as for centrifugal cast iron pipes (6.5.2), except the test pressure which shall be in accordance with table 10.

If carried out the test with compressed air, it should be conducted at an internal pressure not less than 0.1 MPa and within the time checks no less than 10 s; for leak detection, the castings shall be uniformly coated with the outer surface of the respective foaming agent or submerged in water.

6.6 leak Testing of pipes and fittings for gas supply

Pipe and fittings shall be tested with compressed air at an internal pressure not less than 0.1 MPa and within a scan time of not less than: 30 for pipe and 10 for fittings. To determine the leakage pipe and fittings immersed in water or evenly coated on the outer surface of your foam agent.

7 routine tests

7.1 tightness of the joints when tested by internal pressure

The present model test should be performed on the assembled coupling that includes two pipe sections with a length of at least 1 m each (figure 1).

Figure 1

The testing device must ensure a proper clamping of all, regardless of pipe segments are aligned at an angle to each other or subject to transverse load. It should be equipped with a pressure gauge with accuracy class not lower than 3.

The transverse load should be applied to covered by the end of the block -shape with angle of 120°, located at a distance of about 0.5 xmm or 200 mm from the end of the funnel, depending on that more; the bell rests on a flat support. The load should be such that the total shear force is equal to the value specified in 5.2.2, taking into account the weight of pipe, components and geometry of the test structures

, (3)

where , and are expressed in Newtons;

, and shown in figure 1.

Test design fill with water, and the air is accordingly removed, with the exception of pipes for gas supply, in which connections must be tested with air. The pressure should rise gradually until reaching values of the test pressure specified in 5.2.2; the rate of pressure increase should not exceed 0.1 MPa/s. the Test pressure shall be constant within ±0.05 MPa for at least 2 hours; at this time, the connection carefully check every 15 min.

7.2 tightness of the joints when tested external pressure

This type of test design is used only for socket flexible joints. The design shall include two connections of the two pipe sockets connected together and one covering the pipe to create an annular chamber allowing to test one connection under internal pressure and one under external pressure (figure 2).

Figure 2

The test structure is subjected to a transverse load in 5.2.3; one half of this force is applied to the covered end on each side of the test design -shaped block with an angle of 120°, located at a distance of about 0.5 xmm or 200 mm from the end of sockets, whichever is greater; the facets are placed on a flat support.

Test design fill with water, and the air is accordingly removed. The pressure should rise gradually until reaching the test pressure specified in 5.2.3, and then remain constant within ±0.01 MPa for at least 2 hours, at this time, the inner side of the joint under external pressure, carefully check every 15 min.

8 Table sizes

8.1 Pipe bell and the pipe with the covered end

The size of the pipe bell and the pipe with the covered end, shown in figure 3, should conform to the values table 11.

Figure 3

Table 11 — dimensions of the pipe bell and the pipe with the covered end

In millimeters

	Outer diameter *	The thick cast iron walls , 9
40	56	6,0
50	66	6,0
60	77	6,0
65	82	6,0
80	98	6,0
100	118	6,0
125	144	6,0
150	170	6,0
200	222	6,3
250	274	6,8
300	326	7,2
350	378	7,7
400	429	8,1
450	480	8,6
500	532	9,0
600	635	9,9
700	738	10,8
800	842	11,7
900	945	12,6
1000	1048	13,5
1100	1152	14.4 V
1200	1255	15,3
1400	1462	17,1
1500	1565	18,0
1600	1668	18,9
1800	1875	20,7
2000	2082	22,5
2200	2288	24,3
2400	2495	26,1
2600	2702	27,9
* Tolerance: +1 mm (4.2.1.1).

The values given in table 2. The outer and inner coverings is given in 4.4.

8.2 Flanged pipes

Standardized classes () wall thickness, and flange of pipes is given in 8.2.1−8.2.3. Lengths flanged pipes are given in table 3. The outer and inner coverings is given in 4.4

Note — the Dimensions of flanges comply with ISO 7005−2 and EN 1092−2.

8.2.1 Centrifugal cast iron pipe with welded flanges

from 40 to 450 mm:	9, 10, 16, 25 and 40;
from 500 to 600 mm:	9, 10, 16 and 25; 10 to 40;
from 700 to 1600 mm:	9, 10, 16 and 25;
from 1800 to 2600 mm:	9, 10 and 16.

8.2.2 Centrifugal cast pipe with bolted flanges

from 40 to 450 mm:	9 or 10 for 10, 16, 25 and 40;
from 500 to 600 mm:	9 or 10 for 10, 16 and 25; 10 to 40;
from 700 to 1200 mm:	10 for 10, 16 and 25;
from 1400 to 2600 mm:	10 for 10 and 16.

8.2.3 Pipe which are cast with flanges as one unit

from 40 to 600 mm:	12 for 10, 16, 25 and 40;
from 700 to 1600 mm:	12 for 10, 16 and 25;
from 1800 to 2600 mm:	12 for 10 and 16.

8.3 fittings for socket fusion connections

In tables 12−20 all dimensions are nominal value in millimeters. Values and rounded to the nearest multiple of five.

The outer and inner coverings is given in 4.5.

8.3.1 Flanged sockets (figure 4 and table 12)

Figure 4

Table 12 — Dimensions of flanged sockets

In millimeters

		Series A	Series
40	7,0	125	75	67
50	7,0	125	85	78
60	7,0	125	100	88
65	7,0	125	105	93
80	7,0	130	105	109
100	7,2	130	110	130
125	7,5	135	115	156
150	7,8	135	120	183
200	8,4	140	120	235
250	9,0	145	125	288
300	9,6	150	130	340
350	10,2	155	135	393
400	10,8	160	140	445
450	11,4	165	One hundred forty five	498
500	12,0	170	-	550
600	13,2	180	-	655
700	14.4 V	190	-	760
800	15,6	200	-	865
900	16,8	210	-	970
1000	18,0	220	-	1075
1100	19,2	230	-	1180
1200	20,4	240	-	1285
1400	22,8	310	-	1477
1500	24,0	330	-	1580
1600	25,2	330	-	1683
1800	27,6	350	-	1889
2000	30,0	370	-	2095
2200	32,4	390	-	2301
2400	34,8	410	-	2507
2600	37,2	480	-	2713

8.3.2 Flange covered by the ends (figure 5 and table 13)

8.3.3 Narrow sleeve (figure 6 and table 13)

Figure 5

Figure 6

Table 13 — Dimensions covered by the flanged ends and narrow sleeves

In millimeters

		A flange covered by the ends			Narrow sleeve
		Series A	Series		Series A	Series
40	7,0	335	335	200	155	155	67
50	7,0	340	340	200	155	155	78
60	7,0	345	345	200	155	155	88
65	7,0	345	345	200	155	155	93
80	7,0	350	350	215	160	160	109
100	7,2	360	360	215	160	160	130
125	7,5	370	370	220	165	165	156
150	7,8	380	380	225	165	165	183
200	8,4	400	400	230	170	170	235
250	9,0	420	420	240	175	175	288
300	9,6	440	440	250	180	180	340
350	10,2	460	460	260	185	185	393
Four hundred	10,8	480	480	270	190	190	445
450	11,4	500	500	280	195	195	498
500	12,0	520	-	290	200	-	550
600	13,2	560	-	310	210	-	655
700	14.4 V	600	-	330	220	-	760
800	15,6	600	-	330	230	-	865
900	16,8	600	-	330	240	-	970
1000	18,0	600	-	330	250	-	1075
1100	19,2	600	-	330	260	-	1180
1200	20,4	600	-	330	270	-	1285
1400	22,8	710	-	390	340	-	1477
1500	24,0	750	-	410	350	-	1580
1600	25,2	780	-	430	360	-	1683
1800	27,6	850	-	470	380	-	1889
2000	30,0	920	-	500	400	-	2095
2200	32,4	990	-	540	420	-	2301
2400	34,8	1060	-	570	440	-	2507
2600	37,2	1130	-	610	460	-	2713
Note — the length covered by the end to which it is applicable and its tolerance given in table 11.

8.3.4 Knee with double socket 90° (¼) (figure 7 and table 14)

8.3.5 the Knee with double socket 45° (1/8) (figure 8 and table 14)

Figure 7

Figure 8

Table 14 — Sizes of knee length double socket

In millimeters

		90° bend (¼)		Elbows 45° (1/8)
		Series A	Series	Series A	Series
40	7,0	60	85	40	85
50	7,0	70	85	40	85
60	7,0	80	90	45	90
65	7,0	85	90	50	90
80	7,0	100	85	55	50
100	7,2	120	100	65	60
125	7,5	145	115	75	65
150	7,8	170	130	85	70
200	8,4	220	160	110	80
250	9,0	270	240	130	135
300	9,6	320	280	150	155
350	10,2	-	-	175	170
400	10,8	-	-	195	185
450	11,4	-	-	220	200
500	12,0	-	-	240	-
600	13,2	-	-	285	-
700	14.4 V	-	-	330	-
800	15,6	-	-	370	-
900	16,8	-	-	415	-
1000	18,0	-	-	460	-
1100	19,2	-	-	505	-
1200	20,4	-	-	550	-
1400	22,8	-	-	515	-
1500	24,0	-	-	540	-
1600	25,2	-	-	565	-
1800	27,6	-	-	610	-
2000	30,0	-	-	660	-
2200	32,4	-	-	710	-
2400	34,8	-	-	755	-
2600	37,2	-	-	805	-

Knee 8.3.6 double-socket 22°30' (1/16) (figure 9 and table 15)

8.3.7 Knee double-socket 11°15' (1/32) (figure 10 and table 15)

	Figure 9	Figure 10

Table 15 — dimensions of the knees with double socket

In millimeters

		Knee 22°30' (1/16)		Knee 11°15' (1/32)
		Series A	Series	Series A	Series
40	7,0	30	30	25	25
50	7,0	30	30	25	25
60	7,0	35	35	25	25
65	7,0	35	35	25	25
80	7,0	40	40	30	30
100	7,2	40	50	30	30
125	7,5	50	55	35	35
150	7,8	55	60	35	40
200	8,4	65	70	40	45
250	9,0	75	80	50	55
300	9,6	85	90	55	55
350	10,2	95	100	60	60
400	10,8	110	110	65	65
450	11,4	120	120	70	70
500	12,0	130	-	75	-
600	13,2	150	-	85	-
700	14.4 V	175	-	95	-
800	15,6	195	-	110	-
900	16,8	220	-	120	-
1000	18,0	240	-	130	-
1100	19,2	260	-	140	-
1200	20,4	285	-	150	-
1400	22,8	260	-	130	-
1500	24,0	270	-	140	-
1600	25,2	280	-	140	-
1800	27,6	305	-	155	-
2000	30,0	330	-	165	-
2200	32,4	355	-	190	-
2400	34,8	380	-	205	-
2600	37,2	400	-	215	-