FDUS 927 FINAL DRAFT UGANDA STANDARD...For the purpose of deciding whether a particular requirement of this standard is complied with, the final value, observed or calculated, expressing

FINAL DRAFT UGANDA

STANDARD

FDUS 927

First Edition 2011-mm-dd

Reference number FDUS 927: 2011

© UNBS 2011

Polyethylene/aluminium/ polyethylene (PE-AL-PE) and polyethylene-RT/aluminium/ polyethylene-RT (PERT-AL-PERT) composite pressure pipes — Specification

FDUS 927: 2011

ii © UNBS 2011 – All rights reserved

Compliance with this standard does not, of itself confer immunity from legal obligations

A Uganda Standard does not purport to include all necessary provisions of a contract. Users are responsible for its correct application

© UNBS 2011

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any form or by any means, electronic or mechanical, including photocopying and microfilm, without prior written permission from UNBS.

Requests for permission to reproduce this document should be addressed to

The Executive Director Uganda National Bureau of Standards P.O. Box 6329 Kampala Uganda Tel: 256 414 505 995 Fax: 256 414 286 123 E-mail: [email protected] Web: www.unbs.go.ug

mailto:[email protected]

FDUS 927:2011

© UNBS 2010 – All rights reserved iii

Contents Page

Foreword ............................................................................................................................................................. v

1 Scope ...................................................................................................................................................... 1

2 Normative references ............................................................................................................................ 1

3 Requirements ......................................................................................................................................... 1 3.1 Pipe designation .................................................................................................................................... 1 3.2 Materials ................................................................................................................................................. 2 3.2.1 Polyethylene .......................................................................................................................................... 2 3.2.2 UV stabiliser ........................................................................................................................................... 2 3.2.3 Aluminium .............................................................................................................................................. 2 3.2.4 Rework material ..................................................................................................................................... 3 3.3 Pressure rating ...................................................................................................................................... 3 3.4 Nominal outside diameters .................................................................................................................. 3 3.5 Colour ..................................................................................................................................................... 3 3.6 Dimensions of pipe ............................................................................................................................... 3 3.6.1 Diameter and wall thickness ................................................................................................................ 3 3.6.2 Method of measurements ..................................................................................................................... 4 3.6.3 Length of straight pipe.......................................................................................................................... 4 3.6.4 Coiling..................................................................................................................................................... 4 3.7 Visual appearance ................................................................................................................................. 4 3.8 Performance requirements ................................................................................................................... 5 3.8.1 Carbon black content and dispersion ................................................................................................. 5 3.8.2 Pigment dispersion ............................................................................................................................... 5 3.8.3 Adhesion test ......................................................................................................................................... 5 3.8.4 Apparent tensile strength of pipe ........................................................................................................ 5 3.8.5 Minimum burst pressure....................................................................................................................... 5 3.8.6 Hydraulic characteristics ...................................................................................................................... 5

4 Sampling, frequency of tests and criteria for conformity ................................................................. 7 4.1 Type test ................................................................................................................................................. 7 4.1.1 Long term hydrostatic test ................................................................................................................... 8 4.1.2 Thermal stability to oxidation .............................................................................................................. 8 4.1.3 Approval of sample ............................................................................................................................... 8 4.1.4 Failure of sample ................................................................................................................................... 8 4.1.5 Validity period ........................................................................................................................................ 8 4.2 Acceptance test ..................................................................................................................................... 8 4.2.1 Lot ........................................................................................................................................................... 9 4.2.2 Dimensional and visual requirements................................................................................................. 9

5 Marking ................................................................................................................................................. 10

6 Labelling ............................................................................................................................................... 10

Annex A (normative) Outer polyethylene layer thickness .......................................................................... 11 A.1 Sample preparation ............................................................................................................................. 11 A.2 Thickness determination .................................................................................................................... 11

Annex B (normative) Adhesion test .............................................................................................................. 12 B.1 Cutting of the spiral ............................................................................................................................. 12 B.2 Examining for delamination ............................................................................................................... 12

Annex C (normative) Apparent tensile strength test ................................................................................... 13 C.1 Sample size and shape ....................................................................................................................... 13 C.2 Ring tests ............................................................................................................................................. 13

FDUS 927: 2011

iv © UNBS 2011 – All rights reserved

Annex D (normative) Method for determination of oxidation induction time ........................................... 14 D.1 Apparatus ............................................................................................................................................ 14 D.2 Test pieces .......................................................................................................................................... 14 D.3 Procedure ............................................................................................................................................ 14 D.4 Interpretation of the results ............................................................................................................... 15 D.5 Test report ........................................................................................................................................... 15

Annex E (normative) Assessment of pigment dispersion in polyolefin pipes and fittings: Microtome method .............................................................................................................................. 16

E.1 Scope ................................................................................................................................................... 16 E.2 Principle ............................................................................................................................................... 16 E.3 Apparatus ............................................................................................................................................ 16 E.4 Test piece ............................................................................................................................................ 16 E.5 Procedure ............................................................................................................................................ 16 E.6 Expression of results ......................................................................................................................... 16 E.7 Test report ........................................................................................................................................... 17

Annex F (normative) Minimum burst pressure ............................................................................................ 18 F.1 Pipe sample ......................................................................................................................................... 18 F.2 Test temperature ................................................................................................................................. 18 F.3 Burst pressure .................................................................................................................................... 18

Annex G (normative) Sustained pressure test ............................................................................................ 19 G.1 Samples ............................................................................................................................................... 19 G.2 Test procedure .................................................................................................................................... 19 G.3 Failure .................................................................................................................................................. 19

Annex H (informative) Explanatory notes .................................................................................................... 20 H.1 Pressure rating .................................................................................................................................... 20 H.2 Test parameters for hydrostatic test ................................................................................................ 20

Annex J (informative) Non-mandatory Information .................................................................................... 21 J.1 Outside storage ................................................................................................................................... 21 J.2 Connectors and fittings ..................................................................................................................... 21 J.2.1 Internal pressure test ......................................................................................................................... 21 J.2.2 Pull out test ......................................................................................................................................... 22

FDUS 927:2011

© UNBS 2010 – All rights reserved v

Foreword

Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry of Tourism, Trade and Industry established under Cap 327, of the Laws of Uganda. UNBS is mandated to co-ordinate the elaboration of standards and is

(a) a member of International Organisation for Standardisation (ISO) and

(b) a contact point for the WHO/FAO Codex Alimentarius Commission on Food Standards, and

(c) the National Enquiry Point on TBT/SPS Agreements of the World Trade Organisation (WTO).

The work of preparing Uganda Standards is carried out through Technical Committees. A Technical Committee is established to deliberate on standards in a given field or area and consists of representatives of consumers, traders, academicians, manufacturers, government and other stakeholders.

Draft Uganda Standards adopted by the Technical Committee are widely circulated to stakeholders and the general public for comments. The committee reviews the comments before recommending the draft standards for approval and declaration as Uganda Standards by the National Standards Council.

Committee membership

The following organisations were represented on the Building and civil engineering standards Technical Committee (UNBS/TC 3) during the development of this standard:

East African Distributors Ltd

Ministry of Works& Transport

Department of Mines & Geological Surveys

Uganda National Bureau of Standards

FDUS 927: 2011

vi © UNBS 2011 – All rights reserved

Introduction

Polyethylene/Aluminium/Polyethylene (PE-AL-PE) co-extruded composite piping system is a novel small diameter piping (up to 4”) technology for the conveyance of water supply, chemicals, natural gas and liquified petroleum gas for various requirements as mentioned in the scope of this standard.

The PE-AL-PE/PERT-AL-PERT pipe is composed of one metallic layer, two layers of the same polymeric adhesive and two layers of same polyethylene. The inner and outer PE/ layers are bonded to metallic layer (Aluminium tube) by polymeric adhesive during extrusion process.

Due to lamination of an aluminium tube between two layers of PE, these pipes overcome many of the problems associated with conventional pipes. They stay in shape and do not sag and are suitable for both vertical and horizontal run. These pipes are tested for sustained pressure performance requirement at 95

°C

for 170 h. The thermal pressure resistance is higher than HDPE, PPR, CPVC and PVC pipes.

PE-AL-PE/PERT-AL-PERT/ pipes are manufactured and marketed in almost all the advanced countries throughout the world.

The requirements and test methods in this specification cover PE-AL-PE/PERT-AL-PERT/ pipes. Tests on the individual layers that comprise this composite pipe are outside the scope of this specification. The raw materials used, however, shall conform to the requirements in Clause 3.

This specification relates only to metal and plastic composite pipes incorporating a welded metallic tube. The welded metallic tube of itself is capable of sustaining internal pressures. The pipes consisting of metallic layers not welded together are outside the scope of this specification.

This specification excludes cross linked polyethylene-aluminium-cross linked polyethylene pipes.

This standard does not purport to address all the safety problems associated with the use. It is the responsibility of the users of this standard to establish appropriate safety and health practices and determine the applicability or regulatory safety and health practices and determines the applicability of regulatory limitation prior to use.

This specification also gives non-mandatory information regarding storage, connectors and fittings required for use with PE-AL-PE/PERT-AL-PERT composite pressure pipes.

In the formulation of this standard considerable assistance has been derived from the following International Standards:

EAS 381-4, Sampling procedures for inspection by attributes- part 4: Procedures for assessment of declared quality levels

ISO 1872-2, Plastics- Polyethylene (PE) moulding and extrusion materials — Part 2: Preparation of test specimens and determination of properties

US 275, Specification for wrought aluminium and aluminium alloys for general engineering purposes;plates, sheet and strip

US 482-1, High density polyethylene (PE-HD) pipes — Part 1: General quality requirements

US 482-2, High density polyethylene (PE-HD) pipes — Part 2: Dimensions

For the purpose of deciding whether a particular requirement of this standard is complied with, the final value, observed or calculated, expressing the result of test or analysis shall be rounded off in accordance with EAS 124, Rounding off number values. The number of significant places retained in the rounded off value should be the same as that of the specified value in this standard.

FINAL DRAFT UGANDA STANDARD FDUS 927: 2011

© UNBS 2011 – All rights reserved 1

Polyethylene/aluminium/ polyethylene (PE-AL-PE) and polyethylene-RT/aluminium/ polyethylene-RT (PERT-AL-PERT) composite pressure pipes — Specification

1 Scope

This specification covers a coextruded polyethylene composite pressure pipe ranging from 12 mm to 110 mm in diameter. These pipes are used for conveyance of water supply for domestic and industrial purposes including internal and external plumbing, air conditioning, heating installations, CNG, LPG and chemical transportation. This specification includes a system of nomenclature for PE-AL-PE pipes, the requirements and test methods for materials, the dimensions and strengths of finished pipe, adhesion test and the burst and sustained pressure performance test along with requirements and methods for marking.

This specification relates only to metal and plastic composite pipes incorporating a welded metallic tube. The welded metallic tube of itself is capable of sustaining internal pressures. The pipes consisting of metallic layers not welded together are outside the scope of this specification.

This specification excludes fittings and connectors.

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

EAS 381-4, Sampling procedures for inspection by attributes- part 4: Procedures for assessment of declared quality levels

ISO 1872-2, Plastics- Polyethylene (PE) moulding and extrusion materials — Part 2: Preparation of test specimens and determination of properties

US 275, Specification for wrought aluminium and aluminium alloys for general engineering purposes;plates, sheet and strip

US 482-1, High density polyethylene (PE-HD) pipes — Part 1: General quality requirements

US 482-2, High density polyethylene (PE-HD) pipes — Part 2: Dimensions

3 Requirements

3.1 Pipe designation

PE-AL-PE/PERT-AL-PERT/ composite pipes are designated by nominal inside diameters and outside diameters. The concept of dimension ratio is not relevant to PE-AL-PE/PERT-AL-PERT pipe and cannot be used to relate pressure rating with total wall thickness.

FDUS 927: 2011

2 © UNBS 2011 – All rights reserved

3.2 Materials

The material from which PE-AL-PE/PERT-AL-PERT pipe is manufactured shall comprise a polyethylene plastic and aluminium strip.

3.2.1 Polyethylene

Polyethylene compounds used for the manufacture of these pipes shall conform to specifications as follows:

Table-1 — PE and PERT compound characteristics

Characteristics Units Requirements Test parameter Test method

PE

Normal density kg/m3 942 to 948

940.4 to 946.4

27 C

23 C

US 482

Melt flow index g/10 min. 0

0

190 C/

5 kgs

ISO 1872-2

Carbon black content by mass 2.5 % 0.5 % - ISO 1872-2

Thermal stability minute 20 200 C Annex D

Pigment dispersion (coloured pipes)

grade 3 - Annex E

Anti oxidant by mass 0.3 % - ISO 21138

PERT

Normal density kg/m3 942 to 948

23 °C US 482

Melt Flow Index g/10 min. 0.4 to 0.8 190 C/

5 kgs

ISO 1872-2

Carbon black content by mass 2.5 % 0.5 % - 500 C & inert gas ISO 1872-2

Thermal stability minute 20 200 C Annex D

Pigment dispersion

(Coloured pipes)

grade 3 - Annex E

Anti oxidant as per

ISO 21138 by mass 0.3 % ISO 21138

3.2.2 UV stabiliser

The percentage of UV stabiliser used shall not be more than 0.5 % by mass of finished resin (see Table 1). Raw material supplier shall provide a certificate.

3.2.3 Aluminium

The material shall have the following properties and shall be tested as per US 275:

minimum elongation: 20 %; and

ultimate tensile strength: 100 Mpa

The aluminium strip shall have thickness as specified in Table 2.

FDUS 927: 2011


Table 2 — Aluminium thickness and tolerances for PE-AL-PE pipe

Nominal pipe size,

mm

Minimum

Aluminium thickness,

mm

Tolerance on minimum

Aluminium thickness,

mm

0912 0.20 + 0.02

1014 0.20 + 0.02

1216 0.20 + 0.02

1620 0.25 + 0.02

2025 0.25 + 0.02

2532 0.30 + 0.02

3240 0.30 + 0.02

4050 0.30 + 0.02

5063 (0)

6375 (0)

7590 (0)

90110 (0)

3.2.4 Rework material

No rework material shall be used in the manufacture of pipe.

3.3 Pressure rating

The PE-AL-PE composite pipe meeting the requirements of this specification shall be pressure rated for maximum water pressures of 1.38 MPa at 23

°C and 1.10 MPa at 60

°C (see explanatory note).

The PERT-AL-PERT composite pipe meeting the requirements of this specification shall be pressure rated for maximum water pressures of 1.38 MPa at 23

°C and 0.69 MPa at 82

°C.

3.4 Nominal outside diameters

The nominal outside diameter of pipes covered in this standard are 12 mm,14 mm,16 mm,20 mm, 25 mm, 32 mm, 40 mm, 50 mm, 63 mm, 75 mm, 90 mm, 110 mm. Respective nominal inside diameters are 9 mm, 10 mm, 12 mm, 16 mm, 20 mm, 25 mm, 32 mm, 40 mm, 50 mm, 63 mm, 75 mm and 90 mm.

3.5 Colour

Pipe manufactured from compound grade PEEWA45T006 having carbon black shall be black and made from compound grade PEELA45T006 shall be pigmented according to the requirement of the customer.

3.6 Dimensions of pipe

3.6.1 Diameter and wall thickness

Pipe diameter, out of roundness and total wall thickness shall be as given in Table 3. The thickness of the outer layer of polyethylene in the PE-AL-PE pipe shall have a minimum value as specified in Table 3, except for polyethylene material overlaying the weld, which shall have a minimum thickness of half that specified in Table 3.

FDUS 927: 2011


Table 3 — Overall pipe dimensions

Nominal

pipe size,

(mm)

Minimum

outside diameter,

(OD)

(mm)

Tolerance on

minimum OD,

(mm)

Maximum out-

of-roundness,

(mm)

Total wall

thickness, (mm)

Outer PE

layer thickness

minimum, (mm)

Mini-mum

Maxi-mum

0912 12.00 + 0.30 0.30 1.40 1.80 0.40

1014 14.00 + 0.30 0.40 1.70 2.00 0.40

1216 16.00 + 0.30 0.40 1.80 2.10 0.40

1620 20.00 + 0.30 0.60 2.00 2.30 0.40

2025 25.00 + 0.30 0.60 2.50 2.80 0.40

2532 32.00 + 0.50 0.80 2.80 3.20 0.40

3240 40.00 + 0.50 1.00 3.40 3.80 0.40

4050 50.00 + 0.50 1.30 4.00 4.40 0.40

5063 63.00 + 0.50 1.40 4.80 5.40 0.40

6375 75.00 + 0.60 1.50 5.80 6.40 0.40

7590 90.00 + 0.60 1.60 6.80 7.40 0.40

90110 110.00 + 0.60 1.60 7.00 7.80 0.40

3.6.2 Method of measurements

The outside diameter of pipe shall be taken as the average of two measurements taken at right angles. The wall thickness shall be measured by a dial vernier or ball ended micrometer. The resulting dimension shall be expressed to the nearest 0.1 mm.

Ovality shall be measured as the difference between maximum outside diameter and minimum outside diameter measured at the same cross-section of the pipe. For pipes to be coiled, the ovality shall be measured prior to coiling. For coiled pipes, however, re-rounding of pipes shall be carried out prior to the measurement of ovality.

3.6.3 Length of straight pipe

The pipe shall be supplied in straight lengths as agreed upon with the purchaser but the standard length shall be 20 m.

3.6.4 Coiling

The inside diameter of coils in millimetres, shall be not less than 20 times the outside diameter of the pipe.

3.7 Visual appearance

The internal and external surfaces of the pipe shall be smooth, clean and free from grooving and other defects. The ends shall be cleanly cut and shall be square with the axis of the pipes. Slight shallow longitudinal grooves or irregularities in the wall thickness shall be permissible provided that the wall thickness remains within the permissible limits.

FDUS 927: 2011


3.8 Performance requirements

3.8.1 Carbon black content and dispersion

When tested from a composite sample of minimum three pipes in accordance with ISO 1872-2, it shall meet the requirement as given in Table 1 and dispersion of carbon black shall be satisfactory.

3.8.2 Pigment dispersion

When tested in accordance with Annex E the grading shall be 3 (see Table 1).

3.8.3 Adhesion test

There shall be no delamination of the PE and AL, either on bore side or the outside. The test shall be conducted in accordance with Annex B.

3.8.4 Apparent tensile strength of pipe

The pipe rings when tested in accordance with Annex C, shall meet the minimum requirement as specified in Table 4.

Table 4 — Minimum pipe ring strengths and 23 °C burst pressure of PE-AL-PE/PERT-AL-PERT pipe

Nominal pipe size,

mm

Minimum pipe ring strength,

N

Minimum burst pressure,

Mpa

0912 2100 7.0

1014 2100 7.0

1216 2100 6.0

1620 2400 5.0

2025 2400 4.0

2532 2700 4.0

3240 2700 3.5

4050 2700 3.5

5063 3500 3.5

6375 4100 3.5

7590 4700 3.5

90110 5300 3.5

3.8.5 Minimum burst pressure

The minimum burst pressure shall be as given in Table 4, when determined in accordance with Annex F.

3.8.6 Hydraulic characteristics

When subjected to internal pressure creep rupture test in accordance with procedure given in Annex G, the pipe under test shall show no sign of localised swelling, leakage or weeping, and shall not burst during the prescribed test duration. The temperatures, duration of test and pressure for the test shall conform to those specified in Table 5.

FDUS 927: 2011


Table 5 — Hydraulic pressure test conditions and requirements

Nominal pipe size,

mm

Test temperature,

°C

Test pressure,

Mpa

Minimum test duration,

h

PE-AL-PE pipes

0912 20

60

3.2

2.5

1

10

1014

1216

20

60

3.0

2.5

1

10

1620 20

60

2.7

2.5

1

10

2025 20

60

2.6

2.5

1

10

2532 20

60

2.3

2.1

1

10

3240 20

60

2.2

2.0

1

10

4050 20

60

2.1

1.9

1

10

5063 20

60

2.1

1.8

1

10

6375 20

60

2.0

1.8

1

10

7590 20

60

2.0

1.7

1

10

90110 20

60

1.9

1.6

1

10

PERT-AL-PERT pipes

0912 20

60

3.2

2.5

1

10

1014

1216

20

60

3.0

2.5

1

10

1620 20

60

2.7

2.5

1

10

2025 20

60

2.6

2.5

1

10

2532 20

60

2.3

2.1

1

10

3240 20

60

2.2

2.0

1

10

FDUS 927: 2011


Table 5 (continued)

Nominal pipe size,

mm

Test temperature,

°C

Test pressure,

Mpa


h

4050 20

60

2.1

1.9

1

10

5063 20

60

2.1

1.8

1

10

6375 20

60

2.0

1.8

1

10

7590 20

60

2.0

1.7

1

10

90110 20

60

1.9

1.6

1

10

Table 5 (completed)

4 Sampling, frequency of tests and criteria for conformity

4.1 Type test

Type tests are intended to prove the suitability and performance of a new composition, a new technique or a new size of pipe. Such tests need to be applied only when a change is made in polymer composition or method of manufacture, or when a new size is to be introduced. Even if no change in envisaged, type test shall be done at least once in three years of the highest size manufactured during the period. Type test will include the following:

long term hydrostatic test as per Table 6 in accordance with Annex G; and

thermal stability to oxidation in accordance with Annex D.

FDUS 927: 2011


Table 6 — Long term hydrostatic test for PE-AL-PE and PERT-AL-PERTpipes

Nominal pipe

size,

mm

Test temperature,

OC

Test pressure,

Mpa


h

PE-AL-PE pipes PERT-AL-PERT pipes

0912 95 1.3 170 170

1014 95 1.3 170 170

1216 95 1.2 170 170

1620 95 1.0 170 170

2025 95 1.0 170 170

2532 95 0.9 170 170

3240 95 0.9 170 170

4050 95 0.8 170 170

5063 95 0.8 170 170

6375 95 0.8 170 170

7590 95 0.75 170 170

90110 95 0.65 170 170

4.1.1 Long term hydrostatic test

Three samples of same size selected at random shall be tested for compliance with the requirement of the type test as per Table 6.

4.1.2 Thermal stability to oxidation

The minimum Oxidation Induction Time (OIT) of the material from the product shall be 20 min when tested in accordance with Annex D (Table 1).

4.1.3 Approval of sample

If all the samples pass the requirements of the type test, the size of the pipe under consideration shall be considered eligible for the type approval.

4.1.4 Failure of sample

In case of any of the samples fails in the type test, the testing authority, at its discretion, may call for fresh samples not exceeding the original number and subject them to the type test again. If in repeat test, no single failure occurs, the size of the pipe under consideration shall be considered eligible for the type approval. If any of the samples fails in the repeat tests, the size of the pipe under consideration shall not be approved. The manufacturer or the supplier may be asked to improve the design and resubmit the product for type approval.

4.1.5 Validity period

At the end of validity period (normally three years) or earlier as may be necessary, the testing authority may call for fresh samples for type test for the purpose of type approval.

4.2 Acceptance test

Acceptance tests are carried out on samples selected from a lot for the purpose of the lot.

FDUS 927: 2011


4.2.1 Lot

All pipes of the same size and manufactured essentially under similar conditions of manufacture hall constitute a lot. For ascertaining the conformity of the lot to the requirement of this specification, samples shall be selected in accordance with the provision as mentioned under 4.2.2 and 4.2.2.4 and tested for compliance.

4.2.2 Dimensional and visual requirements

4.2.2.1 Test samples

The number of test samples shall be in accordance with the Table 7.

Table 7 — Scale of sampling for visual and dimensional requirements

Number of

pipes/coils in the lot

Sample

number

Sample

size

Cumulative

sample size

Acceptance

number

Rejection

number

(1) (2) (3) (4) (5) (6)

up to 25 First 3 3 0 2

Second 3 6 1 2

26 to 150 First 13 13 0 2

Second 13 26 1 2

151 to 280 First 20 20 0 3

Second 20 40 3 4

281 to 500 First 32 32 1 4

Second 32 64 4 5

501 to 1200 First 50 50 2 5

Second 50 100 6 7

NOTE Pipes are usually manufactured in coils only. Pipes in straight lengths are seldom manufactured. Same sampling will be applicable for pipes manufactured in straight length.

4.2.2.2 Random selection

These pipes shall be selected at random from the lot and in order to ensure the randomness of selection a random number table shall be used. For guidance and use of random number table, ISO 24153 may be referred. In absence of a random number table the following procedure may be adopted.

Starting from any pipe in the lot, count them as 1,2,3,4, …. etc up to r and so on where r is the integral part of N/n, N being the number of pipes in the lot and n is the number of pipes in the samples. Every r

th pipe so

counted shall be drawn so as to constitute the required sample size.

4.2.2.3 Acceptance

The number of pipes given for the first sample in column 3 of Table 7 shall be examined for dimensional and visual requirements given in 3.6.1, 3.6.2, 3.6.3 & 3.7. A pipe failing to satisfy any of these requirements shall be considered as defective. The lot shall be deemed to have satisfied these requirements, if the number of defectives found in the first sample are less than or equal to the corresponding acceptance number given in column 5 of Table 7. The lot shall be deemed not to have met these requirements, if the number of defectives found in the first sample is greater than or equal to the corresponding rejection number given in column 6 of Table 7. If however, the number of defectives found in the first sample lies between the corresponding acceptance and rejection numbers given in column 5 and 6 of Table 7, second sample of size given in column

FDUS 927: 2011


3 of Table 7 shall be taken and examined for these requirements. The lot shall be considered to have satisfied these requirements if the number of defectives found in the cumulative samples is less than or equal to the corresponding acceptance number given in column 5 of table 7; otherwise not.

Hydraulic characteristics, density, MFR, carbon black content /dispersion, adhesion, apparent tensile strength, minimum burst pressure and pigment dispersion tests.

The lot having satisfied dimensional and visual requirements shall be tested for hydraulic characteristics, density, MFR, carbon black content/dispersion, adhesion, apparent tensile strength, minimum burst pressure and pigment dispersion tests requirements.

A separate sample size for each of the tests shall be taken as stipulated in Table 8 and selected at random from the sample already examined for dimensional and visual inspection. All the pipes in each of the sample size shall be tested for compliance in the requirement for density 3.8.1, MFR 3.8.1, Carbon black content/dispersion 3.8.1, pigment dispersion 3.8.2, Adhesion 3.8.3, apparent tensile strength 3.8.4, minimum burst pressure 3.8.5 and hydraulic characteristics 3.8.6.The lot shall be considered to have met the requirements of these tests, if none of the sample tested fails.

Table 8 — Scale of sampling for tests for hydraulic characteristics, density, MFR, Carbon black content/dispersion, Adhesion, Apparent tensile strength, minimum burst pressure and pigment

dispersion

Number of pipes/coils Sample size

up to 100 3

101 to 150 4

151 to 200 5

201 and above 8

5 Marking

The marking shall be repeated at intervals of 1 meter and shall consist of the following information:

manufacturer’s name and trade mark;

designation; and

batch or lot number.

6 Labelling

Two labels of suitable dimensions should be carefully attached to each coil indicating:

suppliers name;

manufacturing standard;

designation;

weight of coil in kilograms; and

length of coil in metres.

FDUS 927: 2011


Annex A (normative)

Outer polyethylene layer thickness

A.1 Sample preparation

Select the sample of pipe at random. Cut the pipe with a sharp knife or other suitable cutter, ensuring that the pipe after cutting is not more than 1 % out-of-round.

A.2 Thickness determination

Use a hand held magnifying glass equipped with graduated reticule or a laboratory microscope with graduated reticule. The reticule should measure to the nearest 0.10 mm. Determine the thickness of outer coating of polyethylene at six points around the circumference. Only one of the points should be at the aluminium weld.

FDUS 927: 2011


Annex B (normative)

Adhesion test

B.1 Cutting of the spiral

Mount a sharp but razor like blade within a protective housing and angle to cut a 45°

± 5° spiral in the pipe.

Choose a PE-AL-PE pipe at random and insert into the housing and rotate to form the spiral cut. The cut goes through the complete wall on one side of the pipe only. Run the spiral along the pipe for a minimum distance along the pipe axis equal to five times the outside diameter.

B.2 Examining for delamination

Hold pipe with the spiral cut firm at the uncut end and create a ribbon of pipe material by opening out the spiral cut pipe. Pliers can be used to grip the spiral cut pipe. Examine the wall of the pipe visually side-on for evidence of delamination between metal and plastic layers (see Figure B.1).

Figure B.1 —Delamination between metal and plastic layers

FDUS 927: 2011


Annex C (normative)

Apparent tensile strength test

C.1 Sample size and shape

Cut the rings of the PE-AL-PE pipe so that two sides are parallel and at 90° ± 2° to the pipe axis. The length

of each ring will be 25 mm ± 1 mm. Cut minimum of 15 samples consecutively along the axis of the pipe.

C.2 Ring tests

Test the consecutively cut samples using a tensile testing machine. Arrange the rings so that the aluminium

weld is at 90° to the tensile axis as shown in Figure C.1. The crosshead speed shall be at 50 mm/min ± 2.5 mm/min. Mount the rings of pipe on two steel rods of minimum diameter of 4 mm. Record the peak force.

Figure C.1 — Schematic presentation of the pipe ring test showing the aluminium weld at 90° to the tensile axis

FDUS 927: 2011


Annex D (normative)

Method for determination of oxidation induction time

D.1 Apparatus

D.1.1 A Differential Thermal Analyser (DTA), calibrated using pure indium and pure tin to give values

which lies within 156.6 °C 0.5 °C and 231.9 °C

0.5 °C

respectively.

The test cell shall allow the cell to be purged within 1 min by use of successive gases at the specified flow rate (see Clause 3).

D.1.2 Aluminium pans, large enough to accommodate a test piece in solid or molten form

D.2 Test pieces

A sample shall be taken by use of a core drill directed radically through the pipe wall. The diameters of the core shall be just less than inner diameter of the sample pan of the thermal analyser, and care should be taken not to overheat the sample during the coring operation. Using a scalpel, cut test pieces that weigh 15

mg 0.5 mg. In the form of discs from the core sample, selecting the inner surface, outer surface and mid-wall as the minimum sample points which are to be tested individually.

D.3 Procedure

Except where this method differs, follow the operating instructions of the instrument manufacturer as applicable.

Establish a nitrogen flow of 50 mL per min through the DTA cell. Check that when a switchover to nitrogen is made, the gas flow will continue at the rate and then revert to a nitrogen flow of 50 mL per minute.

Introduce a test piece in an open aluminium pan and an empty aluminium reference pan into the cell. Set the

instrument to raise the temperature at a rate of 20 °C /min and then to run isothermally at 200 °C 0.1 °C

and

allow the temperature to stabilise. Make any minor corrections to the heater voltage to bring the specimen

temperature to 200 °C 0.1 °C. Start to record the thermogram, (that is, a plot of the temperature differential against time).

When steady condition exists under nitrogen after five minutes, switch over to oxygen and mark this point on the thermogram.

Continue to run the thermogram until the oxidation exotherm has occurred and has reached its maximum.

FDUS 927: 2011


Figure D.1 — Thermogram (plot of the temperature differential against time)

D.4 Interpretation of the results

The oxidation induction time for the test is the time taken, in minutes from the introduction of oxygen to the intercept of the extended base line and the extended tangent drawn to the exotherm at the point of maximum slope as shown in Figure D.1.

The thermal stability of the sample is the arithmetic mean of at least five oxidation induction time measurement at 200 °C or 210 °C.

D.5 Test report

The test report shall include the following:

a) identification of the test pieces;

b) reference to this test method;

c) individual results in minutes; and

d) date of the test.

FDUS 927: 2011


Annex E (normative)

Assessment of pigment dispersion in polyolefin pipes and fittings:

Microtome method

E.1 Scope

This annex describes the method for the assessment of pigment dispersion in polyolefin pipes and fittings.

E.2 Principle

A microtomed section of material is examined by transmitted light at a magnification of X 100 and compared against standard photomicrographs.

E.3 Apparatus

E.3.1 Microtome

E.3.2 Microscope of at least X100 linear magnification and circular field of view of 0.7 mm 0.07 mm diameter set for transmitted light.

E.3.3 Microscope slides and cover slips

E.4 Test piece

Microtome section 10 um to 20 µm thick shall be cut from across section of the pipe or the fitting. They shall have an area of approximately 7.0 mm

2.

Six test pieces shall be taken from different parts of the cross section.

NOTE It is often easier to take microtome sections if the pipe or fitting has been cooled to below room temperature.

E.5 Procedure

Place the pieces on a microscope slide so that each one is equidistant from its neighbour(s) and from adjacent edge(s) of the slide and cover with Canada balsam before placing a cover slip over the test pieces.

Examine the six test pieces in turn through the microscope at a linear magnification of X 100 10. Scan the whole of each test piece and compare the worst field of view of each with the standard photomicrographs numbered 1 to 6.

Give to each of the six test pieces a numerical rating corresponding to the number of the photomicrograph equivalent to the worst field of view of each test piece.

E.6 Expression of results

Record the rating of each test piece as per outcomes of photomicrograms.

FDUS 927: 2011


E.7 Test report

The test report shall include the following:

a) full identification of pipe or fitting from which the test pieces were taken;

b) individual rating of each test piece; and

c) date of testing.

FDUS 927: 2011


Annex F (normative)

Minimum burst pressure

F.1 Pipe sample

Select a length of PE-AL-PE pipe at random and prepare five consecutive lengths of required length (200 mm minimum). Seal samples at the ends with appropriate fittings and test either free or fixed end.

F.2 Test temperature

The test should be carried out at ambient temperature inside the laboratory. The temperature should

preferably be 25 °C ± 5 °C.

F.3 Burst pressure

Increase the pressure inside the pipe in such a way that the time required to reach the burst pressure is between 60 s to 70 s.

FDUS 927: 2011


Annex G (normative)

Sustained pressure test

G.1 Samples

Each test sample of PE-AL-PE pipe shall have a minimum length between end closures of at least ten times the average outside diameter of the pipe, but not less than 250 mm. Seal specimens at both ends with appropriate fittings and fill the sample with water.

G.2 Test procedure

Test each sample individually in a temperature controlled water bath. Condition the test samples for at least two hours in the water bath when the water bath is at the required test temperature. Maintain the pressure indicated in Table 4 within 0.07 MPa of the set pressures for the duration of the test.

G.3 Failure

Any continuous loss of pressure of the test sample shall constitute failure of the test.

FDUS 927: 2011


Annex H (informative)

Explanatory notes

H.1 Pressure rating

The hydrostatic design basis is based on the recommendation by the Plastic Pipe Institute as given in ASTM F 1282-95 ‘Standard Specification for Polyethylene/Aluminium/Polyethylene(PE-AL-PE) Composite Pressure Pipe’. According to this recommendation the design bases pressures are 2.76 MPa at 23

°C and 2.21 MPa at

600 C for 50 years service. These hydrostatic design bases-pressure apply only to pipe meeting all of the

requirement of this specification.

H.2 Test parameters for hydrostatic test

H.2.1 For 20 °C. temperature 1 h test, the test pressures are calculated for stress value of 12 MPa based on WH/92/1 ‘Specification for macro-composite PE/AL/PE and PE-X/AL/PE-X thermoplastics pipes and associated connectors for hot and cold water for domestic purposes and heating installations in buildings.’

H.2.2 For 60 °C. temperature 10 h test, test pressures are as per ASTM F 1282 – 95 ‘Standard Specification for Polyethylene/Aluminium/Polyethylene (PE-AL-PE) Composite Pressure Pipe, for sizes upto 25 mm OD pipe. The test pressure for sizes more than 25 mm OD, the values are arrived at by extrapolation.

H.2.3 For 95 °C. temperature 170 h Type Test, the test pressures are calculated for stress value of 4.7 MPa based on WH/92/1 ‘Specification for macro-composite PE/AL/PE and PE-X/AL/PE-X thermoplastics pipes and associated connectors for hot and cold water for domestic purposes and heating installations in buildings’.

FDUS 927: 2011


Annex J (informative)

Non-mandatory Information

J.1 Outside storage

Pipe should be stored on a flat surface and supported in a manner that will prevent distortion.

J.2 Connectors and fittings

PE-AL-PE pipes manufactured to this specifications shall be capable of being jointed with suitable connectors or fittings provided that the connector or fitting alone or in assembly with PE-AL-PE pipe complies with the requirements as in J.2.1 – J.2.2.

J.2.1 Internal pressure test

The fitting or connector, when assembled with PE-AL-PE pipe, shall not fail, or weep at the test pressure and temperatures for the specified duration. The joint shall not have any leakage during the test.

Test temperature: Ambient

Table J.1 — Test pressure and duration

Pipe size,

mm

Test pressure,

Bar*

Duration,

h

1014 36.0 1

1216 34.3 1

1620 26.7 1

2025 26.7 1

2532 23.0 1

3240 22.3 1

4050 20.4 1

5063 20.0 1

6375 19.0 1

7590 19.0 1

90110 17.0 1

* 1 Bar = 1.019762 kgf/cm2

FDUS 927: 2011


J.2.2 Pull out test

J.2.2.1 Apparatus

J.2.2.1.1 Tensile testing machine together with grips capable of subjecting the test assembly to a constant longitudinal force

J.2.2.1.2 Frame with means for suspending a test piece together with stirrup at the lower end to hold sufficient weight(s) with which to apply the specified force

J.2.2.2 Test assembly

The test assembly shall comprise a straight coupling or any other fitting which can joint two pipe pieces assembled in accordance with the manufacturer’s instructions with two pieces of pipe of the appropriate nominal size. Separate combinations shall be assembled for each type of of pipe for which fitting is designed. Each pipe piece shall be at least 100 mm in length.

J.2.2.3 Procedure

Secure the test assembly in the apparatus and apply gradually over a period of 30 seconds the appropriate force as given in J.2 as applicable. Hold the specimen in constant tension for the specified duration.

NOTE The pull out test forces have been calculated using the following formula:

F = 1.5 (D2

-d2

)/4

where

F is the applied force (in N);

is the design circumferential stress = 6.3 Mpa;

D is the nominal outside diameter, in millimetres, of the pipe;

d is the internal diameter of the pipe, in millimetres, with minimum wall thickness.

Table J.2 — Test load and duration

Pipe size,

mm

Test load,

N

Duration,

h

1014 620 1

1216 740 1

1620 1068 1

2025 1640 1

2532 2427 1

3240 3694 1

4050 5463 1

5063 6600 1

6375 7800 1

7590 9000 1

90110 10000 1

Test temperature: Ambient.

FDUS 927: 2011


Certification marking

Products that conform to Uganda standards may be marked with Uganda National Bureau of Standards (UNBS) Certification Mark shown in the figure below.

The use of the UNBS Certification Mark is governed by the Standards Act, and the Regulations made thereunder. This mark can be used only by those licensed under the certification mark scheme operated by the Uganda National Bureau of Standards and in conjunction with the relevant Uganda Standard. The presence of this mark on a product or in relation to a product is an assurance that the goods comply with the requirements of that standard under a system of supervision, control and testing in accordance with the certification mark scheme of the Uganda National Bureau of Standards. UNBS marked products are continually checked by UNBS for conformity to that standard.

Further particulars of the terms and conditions of licensing may be obtained from the Director, Uganda National Bureau of Standards.

FDUS 927: 2011

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