ASTM A674-10(2014)

Standard Practice for Polyethylene Encasement for Ductile Iron Pipe for Water or Other Liquids

ABSTRACT
This practice covers the standard materials and installation procedures for polyethylene encasement to be applied to underground installations of ductile iron pipe for water or other liquids. It may also be used for polyethylene encasement of fittings, valves, and other appurtenances to ductile iron pipe systems. Linear low-density and high-density cross-laminated polyethylene films shall be manufactured of virgin polyethylene material, and shall conform to the required group, density, dielectric strength, and volume resistivity specifications. The polyethylene encasement material shall also be in accordance to the tensile strength, elongation, dielectric strength, impact resistance, and propagation tear resistance requirements. The polyethylene encasement shall be installed in such a way that it shall prevent contact between the pipe and the surrounding backfill and bedding material without intending to be a completely airtight or watertight enclosure. The polyethylene film shall be fitted to the contour of the pipe with sufficient slack to prevent stretching the polyethylene bridging irregular surfaces. For installations below the water table or in areas subject to tidal actions, or both, it is recommended that tube-form polyethylene be used with both ends sealed as thoroughly as possible with adhesive tape or plastic tie straps at the joint overlap.
SCOPE
1.1 This practice covers materials and installation procedures for polyethylene encasement to be applied to underground installations of ductile iron pipe. It may also be used for polyethylene encasement of fittings, valves, and other appurtenances to ductile iron pipe systems.  
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.  
1.2.1 Important SI values are provided in brackets. Also, certain important SI values appear without brackets or parentheses.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 30-Sep-2014
• ICS: 23.040.10 - Iron and steel pipes
• Technical Committee: A04 - Iron Castings
• Drafting Committee: A04.12 - Pipes and Tubes

Relations

• Replaces: ASTM A674-10 - Standard Practice for Polyethylene Encasement for Ductile Iron Pipe for Water or Other Liquids
• Effective Date: 01-Oct-2014
• Referred By: ASTM G218-19 - Standard Guide for External Corrosion Protection of Ductile Iron Pipe Utilizing Polyethylene Encasement Supplemented by Cathodic Protection
• Effective Date: 01-Oct-2014

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: A674 − 10 (Reapproved 2014)
Standard Practice for
Polyethylene Encasement for Ductile Iron Pipe for Water or
Other Liquids
This standard is issued under the fixed designation A674; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2.2 ANSI/AWWA Standards:
C 600 Installation of Ductile Iron Water Mains and Their
1.1 This practice covers materials and installation proce-
Appurtenances
dures for polyethylene encasement to be applied to under-
C 105⁄A21.5 Polyethylene Encasement for Ductile-Iron
groundinstallationsofductileironpipe.Itmayalsobeusedfor
Pipe Systems
polyethylene encasement of fittings, valves, and other appur-
tenances to ductile iron pipe systems.
3. Terminology
1.2 The values stated in inch-pound units are to be regarded
3.1 Definitions:
as standard. The values given in parentheses are mathematical
3.1.1 high-density, cross-laminated polyethylene film—Film
conversions to SI units that are provided for information only
extruded from virgin high-density polyethylene raw material,
and are not considered standard.
which is then molecularly oriented by stretching. The final
1.2.1 Important SI values are provided in brackets. Also,
product is then formed by two single-ply layers of the film that
certain important SI values appear without brackets or paren-
arethenlaminatedtogetherwiththeirorientationsat90°toone
theses.
another using molten, high-density, virgin resin.
1.3 This standard does not purport to address all of the
3.1.2 linear low-density polyethylene film—Film extruded
safety concerns, if any, associated with its use. It is the
from virgin linear low-density polyethylene raw material.
responsibility of the user of this standard to establish appro-
3.1.3 polyethylene encasement—polyethylene material, in
priate safety and health practices and determine the applica-
tube or sheet form, that is used to encase ductile iron pipe.
bility of regulatory limitations prior to use.
3.1.4 securing overlap—any one of various methods of
2. Referenced Documents
holding polyethylene encasement in place at the point of
overlapuntilbackfillingoperationsarecompleted.Thismaybe
2.1 ASTM Standards:
accomplished with adhesive tape or plastic tie straps.
D149 Test Method for Dielectric Breakdown Voltage and
DielectricStrengthofSolidElectricalInsulatingMaterials
4. Requirements
at Commercial Power Frequencies
D882 Test Method for Tensile Properties of Thin Plastic
4.1 Materials:
Sheeting
4.1.1 General—All films shall be manufactured of virgin
D1709 Test Methods for Impact Resistance of Plastic Film
polyethylene material as non-virgin polyethylene materials
by the Free-Falling Dart Method
may be susceptible to accelerated environmental degradation.
D1922 Test Method for Propagation Tear Resistance of
4.1.1.1 Requirements—The sections that follow list the
Plastic Film and Thin Sheeting by Pendulum Method
material requirements for linear low-density and high-density,
D4976 Specification for Polyethylene Plastics Molding and
cross-laminated polyethylene film. In each category, the film
Extrusion Materials
shall meet all of the listed requirements.
4.1.2 Linear low-density polyethylene film—Linear low-
density polyethylene film shall be manufactured of virgin
This practice is under the jurisdiction of ASTM Committee A04 on Iron
polyethylene material conforming to the requirements of
Castings and is the direct responsibility of Subcommittee A04.12 on Pipes and
Specification D4976 shown in Table 1.
Tubes.
Current edition approved Oct. 1, 2014. Published October 2014. Originally 4.1.2.1 Thickness—Linear low-density polyethylene film
approved in 1972. Last previous edition approved in 2010 as A674 - 10. DOI:
shall have a minimum thickness of 0.008 in. [0.20 mm].
10.1520/A0674-10R14.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on Available fromAmerican Water WorksAssociation (AWWA), 6666 W. Quincy
the ASTM website. Ave., Denver, CO 80235, http://www.awwa.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
A674 − 10 (2014)
A
TABLE 1 Linear Low-Density Polyethylene Characteristics TABLE 3 Polyethylene Tube Sizes for Push-On Joint Pipe
Nominal Pipe Diameter, in. Recommended Polyethylene
Raw Material Used to Manufacture Polyethylene Encasement Material
B
Flat Tube Width, in. [cm]
Group, density, and dielectric strength in accordance with the latest revision of
3 14 [36]
Specification D4976
4 14 [36]
Group 2 (Linear)
6 16 [41]
Density 0.910 to 0.935 g/cm
8 20 [51]
Dielectric strength, volume resistivity 10 ohm-cm, min
10 24 [61]
Polyethylene Encasement Material
12 27 [69]
Tensile strength 3600 psi (24.83 MPa), for an 8 mil
14 30 [76]
(200µm) minimum thickness, or 28.8
16 34 [86]
lbf/in. width (50.4 N/cm width), mini-
18 37 [94]
mum in machine and transverse di-
20 41 [104]
rection (ASTM D882)
24 54 [137]
Elongation 700 %, min in the machine and
30 67 [170]
transverse direction (ASTM D882)
36 81 [206]
Dielectric strength 800 V/mil (31.5 V/µm) thickness,
42 81 (206)
min (ASTM D149)
48 95 [241]
Impact resistance 600 g, min (ASTM D1709 Method
54 108 [274]
B)
60 108 [274]
Propagation tear resistance 2550 gf, min in machine and trans-
64 121 [307]
verse direction (ASTM D1922)
A
These wrap sizes should work with most push-on joint pipe and fitting bell sizes.
Where bell circumferences are larger than the sheet sizes shown, the bell areas
shouldbecarefullywrappedwithcutfilmsections,effectivelylappingandsecuring
cut edges as necessary; or, alternatively, sufficiently large tube or sheet film to
effectively cover these joints should be ordered.
B
For flat sheet polyethylene, see 5.3.3.
4.1.3 High-density cross-laminated polyethylene film—
High-density cross-laminated polyethylene film shall be manu-
factured of virgin polyethylene material conforming to the
4.4 Marking requirements—Polyethylene film shall be
requirements of Specification D4976 shown in Table 2.
clearly marked at a minimum of every 2 ft [0.6 m] along its
4.1.3.1 Thickness—High-density cross-laminated polyethyl-
length with print that does not contain hazardous material.
ene film shall have a minimum thickness of 0.004 in. [0.10
Marking shall contain the following information:
mm].
(a) Manufacturer’s name or registered trademark
4.2 Tube Size—The tube size for each pipe diameter shall be
(b) Year of manufacture
as listed in Table 3.
(c) ASTM A674
4.3 Color—Polyethylene film may be supplied in its natural (d) Minimum film thickness and material type (LLDPE or
color, white, black or weather resistant black containing not HDCLPE)
less than 2 % carbon black with a particle diameter of 90 nm (e) Applicable range of nominal pipe diameter size(s)
or less. A minimum2%ofa hindered-amine ultraviolet (f) Warning—Corrosion Protection—Repair Any Damage
inhibitor is required for all films other than the weather- 4.4.1 Marking height—Letters and numerals used for mark-
resistant black film with carbon black. Where other colors are ing items a through e in Section 4.4 shall not be less than 1 in.
specified for purposes of identification, the pigmentation shall [25.4 mm] in height. Item f in Section 4.4 shall be not less than
not contain any regulated substances. 1 ⁄2 in. [38.10 mm] in height.
5. Installation
TABLE 2 High-Density Cross-Laminated Polyethylene
5.1 General:
Characteristics
5.1.1 The polyethylene encasement shall prevent contact
Raw Material Used to Manufacture Polyethylene Encasement Material
between the pipe and the surrounding backfill and bedding
Group, density, and dielectric strength in accordance with the latest revision
material but is not intended to be a completely airtight or
of Specification D4976
watertight enclosure. All lumps of clay, mud, cinders, etc.
Group 2 (Linear)
which may be on the pipe surface shall be removed prior to
Density 0.940 to 0.960 g/cm
Dielectric strength, volume resistivity 10 ohm-cm, min
installation of the polyethylene encasement. During
installation, care shall be exercised to prevent soil or embed-
High-Density Cross-Laminated Polyethylene Encasement Material
ment material from becoming entrapped between the pipe and
Tensile strength 6300 psi (43.47 MPa), for a 4 mil (100
the polyethylene.
µm) minimum thickness, or 25.2 lbf/in.
width (44.1 N/cm width), minimum in
5.1.2 The polyethylene film shall be fitted to the contour of
machine and transverse direction
the pipe to effect a snug, but not tight, encasement with
(ASTM D882)
minimum space between the polyethylene and the pipe. Suffi-
Elongation 100 %, min in machine and transverse
direction (ASTM D882)
cientslackshallbeprovidedincontouringtopreventstretching
Dielectric strength 800 V/mil (31.5 V/µm) thickness, min
the polyethylene bridging irregular surfaces, such as bell-
(ASTM D149)
spigot interfaces, bolted joints, or fittings, and to prevent
Impact resistance 800 g, min. (ASTM D1709 Method B)
Propagation tear resistance 250 gf, min. in machine and transverse
damage to the polyethylene due to backfilling operations.
direction (ASTM D1922)
Overlaps and ends shall be secured by the use of adhesive tape
or plastic tie straps.
A674 − 10 (2014)
5.1.3 For installations below the water table or in areas bare pipe at each end. Make the polyethylene snug, but not
subject to tidal actions, or both, it is recommended that tight, as shown in Fig. 2; secure ends as described in 5.1.
tube-form polyethylene be used with both ends sealed as
5.3.2.2 Before making up a joint, slip a 3-ft [0.9-m] length
thoroughly as possible with adhesive tape or plastic tie straps
ofpolyethylenetubeovertheendoftheprecedingpipesection,
atthejointoverlap.Itisalsorecommendedthatcircumferential
bunching it accordion fashion lengthwise. Alternatively, place
wraps of tape or plastic tie straps be placed at 2 ft [0.6 m]
a 3-ft [0.9 m] length of polyethylene sheet in the trench under
intervalsalongthebarrelofthepipetohelpminimizethespace
the joint to be made. After completing the joint, pull the 3-ft
between the polyethylene and the pipe.
lengthofpolyethyleneoveroraroundthejoint,overlappingthe
5.2 Polyethylene Installers—The polyethylene encasement previously installed on each adjacent section of pipe by at least
1 ft [0.3 m]; make snug and secure each end as described in
shall be installed by personnel trained or experienced in the
proper application of the encasement as described in this 5.1. A shallow bell hole must be made at joints to facilitate
installation of the polyethylene tube or sheet.
standard. At all times during construction of the pipeline,
precautionsshallbetakentopreventdamagetotheencasement
5.3.2.3 Repair any rips, punctures, or other damage to the
film.
polyethylene as described in 5.6. Proceed with installation of
the next section of pipe in the same manner.
5.3 Methods of Installation—This practice includes three
different methods for the installation of polyethylene encase-
5.3.3 Method C (see Fig. 4):
ment. MethodAand B are for use with polyethylene tubes and
5.3.3.1 Flat sheet polyethylene shall have a minimum width
Method C is for use with polyethylene sheets.
twice the flat tube width shown in Table 3.
5.3.1 Method A (see Fig. 1):
5.3.3.2 Cutthepolyethylenesheettoalengthapproximately
5.3.1.1 Cut the polyethylene tube to a length approximately
2 ft [0.6 m] longer than the length of pipe section. Center the
2 ft [0.6 m] longer than the length of the pipe section. Slip the
cut length to provide a 1-ft [0.3-m] overlap on each adjacent
tube around the pipe, centering it to provide a 1-ft [0.3-m]
pipe section, bunching it until it clears the pipe ends. Wrap the
overlap on each adjacent pipe section, and bunching it accor-
polyethylene around the pipe so that it overlaps circumferen-
dion fashion lengthwise until it clears the pipe ends.
tially over the top quadrant of the pipe. Secure the cut edge of
5.3.1.2 Lower the pipe into the trench and make up the pipe
polyethylene sheet at approximately 3-ft [0.9-m] intervals
joint with the preceding section of pipe. A shallow bell hole
along the pipe length.
must be made at joints to facilitate installation of the polyeth-
5.3.3.3 Lowerthewrappedpipeintothetrenchandmakeup
ylene tube.
the pipe joint with the preceding section of pipe.Ashallow bell
5.3.1.3 After assembling the pipe joint, make the overlap of
hole must be made at joints to facilitate installation of the
the polyethylene tube. Pull the bunched polyethylene from the
polyethylene. After completing the joint, make the overlap as
preceding length of pipe, slip it over the end of the new length
described in 5.1.
of pipe, and secure in place. Then slip the end of the
5.3.3.4 Repair any rips, punctures, or other damage to the
polyethylenefromthenewpipesectionovertheendofthefirst
polyethylene as described in 5.6. Proceed with installation of
wrap until it overlaps the joint at the end of the preceding
the next section of pipe in the same manner.
length of pipe. Secure the overlap in place. Take up the slack
width at the top of the pipe as shown in Fig. 2, to make a snug,
5.4 Pipe-Shaped Appurtenances—Bends, reducers, offsets,
but not tight, fit along the barrel of the pipe, securing the fold
and other pipe-shaped appurtenances shall be covered with
at quarter points.
polyethylene in the same manner as the pipe.
5.3.1.4 Repair any rips, punctures, or other damage to the
5.5 Odd-Shaped Appurtenances—Wrap valves, tees,
polyethylene with adhesive tape or with a short length of
polyethylene tube cut open, wrapped around the pipe, and crosses, and other odd-shaped pieces which cannot practically
be wrapped in a tube, with a flat sheet or split length of
secured in place. Proceed with installation of the next section
of pipe in the same manner. polyethylene tube. Pass the sheet under the appurtenance and
bring up around the body. Make seams by bringing the edges
5.3.2 Method B (see Fig. 3):
5.3.2.1 Cut the polyethylene tube to a length approximately together, folding over twice, and taping down. Handle slack
1 ft [0.3 m] shorter than the length of the pipe section. Slip the width and overlaps at joints as described in 5.1. Tape polyeth-
tube around the pipe, centering it to provide 6 in. [150 mm] of ylene securely in place at valve stem and other penetrations.
FIG. 1 Method A
A674 − 10 (2014
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: A674 − 10 A674 − 10 (Reapproved 2014)
Standard Practice for
Polyethylene Encasement for Ductile Iron Pipe for Water or
Other Liquids
This standard is issued under the fixed designation A674; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This practice covers materials and installation procedures for polyethylene encasement to be applied to underground
installations of ductile iron pipe. It may also be used for polyethylene encasement of fittings, valves, and other appurtenances to
ductile iron pipe systems.
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only and are not considered standard.
1.2.1 Important SI values are provided in brackets. Also, certain important SI values appear without brackets or parentheses.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2.1 ASTM Standards:
D149 Test Method for Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating Materials at
Commercial Power Frequencies
D882 Test Method for Tensile Properties of Thin Plastic Sheeting
D1709 Test Methods for Impact Resistance of Plastic Film by the Free-Falling Dart Method
D1922 Test Method for Propagation Tear Resistance of Plastic Film and Thin Sheeting by Pendulum Method
D4976 Specification for Polyethylene Plastics Molding and Extrusion Materials
2.2 ANSI/AWWA Standards:
C 600 Installation of Ductile Iron Water Mains and Their Appurtenances
C 105 ⁄A21.5 Polyethylene Encasement for Ductile-Iron Pipe Systems
3. Terminology
3.1 Definitions:
3.1.1 high-density, cross-laminated polyethylene film—Film extruded from virgin high-density polyethylene raw material, which
is then molecularly oriented by stretching. The final product is then formed by two single-ply layers of the film that are then
laminated together with their orientations at 90° to one another using molten, high-density, virgin resin.
3.1.2 linear low-density polyethylene film—Film extruded from virgin linear low-density polyethylene raw material.
3.1.3 polyethylene encasement—polyethylene material, in tube or sheet form, that is used to encase ductile iron pipe.
3.1.4 securing overlap—any one of various methods of holding polyethylene encasement in place at the point of overlap until
backfilling operations are completed. This may be accomplished with adhesive tape or plastic tie straps.
4. Requirements
4.1 Materials:
This practice is under the jurisdiction of ASTM Committee A04 on Iron Castings and is the direct responsibility of Subcommittee A04.12 on Pipes and Tubes.
Current edition approved Oct. 1, 2010Oct. 1, 2014. Published November 2010October 2014. Originally approved in 1972. Last previous edition approved in 20052010
as A674 - 05.A674 - 10. DOI: 10.1520/A0674-10.10.1520/A0674-10R14.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Available from American Water Works Association (AWWA), 1401 New York Ave., NW, Suite 640, Washington, DC 20005.6666 W. Quincy Ave., Denver, CO 80235,
http://www.awwa.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
A674 − 10 (2014)
4.1.1 General—All films shall be manufactured of virgin polyethylene material as non-virgin polyethylene materials may be
susceptible to accelerated environmental degradation.
4.1.1.1 Requirements—The sections that follow list the material requirements for linear low-density and high-density,
cross-laminated polyethylene film. In each category, the film shall meet all of the listed requirements.
4.1.2 Linear low-density polyethylene film—Linear low-density polyethylene film shall be manufactured of virgin polyethylene
material conforming to the requirements of Specification D4976 shown in Table 1.
4.1.2.1 Thickness—Linear low-density polyethylene film shall have a minimum thickness of 0.008 in. [0.20 mm].
4.1.3 High-density cross-laminated polyethylene film—High-density cross-laminated polyethylene film shall be manufactured of
virgin polyethylene material conforming to the requirements of Specification D4976 shown in Table 2.
4.1.3.1 Thickness—High-density cross-laminated polyethylene film shall have a minimum thickness of 0.004 in. [0.10 mm].
4.2 Tube Size—The tube size for each pipe diameter shall be as listed in Table 3.
4.3 Color—Polyethylene film may be supplied in its natural color, white, black or weather resistant black containing not less
than 2 % carbon black with a particle diameter of 90 nm or less. A minimum 2 % of a hindered-amine ultraviolet inhibitor is
required for all films other than the weather-resistant black film with carbon black. Where other colors are specified for purposes
of identification, the pigmentation shall not contain any regulated substances.
4.4 Marking requirements—Polyethylene film shall be clearly marked at a minimum of every 2 ft [0.6 m] along its length with
print that does not contain hazardous material. Marking shall contain the following information:
(a) Manufacturer’s name or registered trademark
(b) Year of manufacture
(c) ASTM A674
(d) Minimum film thickness and material type (LLDPE or HDCLPE)
(e) Applicable range of nominal pipe diameter size(s)
(f) Warning—Corrosion Protection—Repair Any Damage
4.4.1 Marking height—Letters and numerals used for marking items a through e in Section 4.4 shall not be less than 1 in. [25.4
mm] in height. Item f in Section 4.4 shall be not less than 1 ⁄2 in. [38.10 mm] in height.
5. Installation
5.1 General:
5.1.1 The polyethylene encasement shall prevent contact between the pipe and the surrounding backfill and bedding material
but is not intended to be a completely airtight or watertight enclosure. All lumps of clay, mud, cinders, etc. which may be on the
pipe surface shall be removed prior to installation of the polyethylene encasement. During installation, care shall be exercised to
prevent soil or embedment material from becoming entrapped between the pipe and the polyethylene.
5.1.2 The polyethylene film shall be fitted to the contour of the pipe to effect a snug, but not tight, encasement with minimum
space between the polyethylene and the pipe. Sufficient slack shall be provided in contouring to prevent stretching the polyethylene
bridging irregular surfaces, such as bell-spigot interfaces, bolted joints, or fittings, and to prevent damage to the polyethylene due
to backfilling operations. Overlaps and ends shall be secured by the use of adhesive tape or plastic tie straps.
5.1.3 For installations below the water table or in areas subject to tidal actions, or both, it is recommended that tube-form
polyethylene be used with both ends sealed as thoroughly as possible with adhesive tape or plastic tie straps at the joint overlap.
TABLE 1 Linear Low-Density Polyethylene Characteristics
Raw Material Used to Manufacture Polyethylene Encasement Material
Group, density, and dielectric strength in accordance with the latest revision of
Specification D4976
Group 2 (Linear)
Density 0.910 to 0.935 g/cm
Dielectric strength, volume resistivity 10 ohm-cm, min
Polyethylene Encasement Material
Tensile strength 3600 psi (24.83 MPa), for an 8 mil
(200μm) minimum thickness, or 28.8
lbf/in. width (50.4 N/cm width), mini-
mum in machine and transverse di-
rection (ASTM D882)
Elongation 700 %, min in the machine and
transverse direction (ASTM D882)
Dielectric strength 800 V/mil (31.5 V/μm) thickness,
min (ASTM D149)
Impact resistance 600 g, min (ASTM D1709 Method
B)
Propagation tear resistance 2550 gf, min in machine and trans-
verse direction (ASTM D1922)
A674 − 10 (2014)
TABLE 2 High-Density Cross-Laminated Polyethylene
Characteristics
Raw Material Used to Manufacture Polyethylene Encasement Material
Group, density, and dielectric strength in accordance with the latest revision
of Specification D4976
Group 2 (Linear)
Density 0.940 to 0.960 g/cm
Dielectric strength, volume resistivity 10 ohm-cm, min
High-Density Cross-Laminated Polyethylene Encasement Material
Tensile strength 6300 psi (43.47 MPa), for a 4 mil (100
μm) minimum thickness, or 25.2 lbf/in.
width (44.1 N/cm width), minimum in
machine and transverse direction
(ASTM D882)
Elongation 100 %, min in machine and transverse
direction (ASTM D882)
Dielectric strength 800 V/mil (31.5 V/μm) thickness, min
(ASTM D149)
Impact resistance 800 g, min. (ASTM D1709 Method B)
Propagation tear resistance 250 gf, min. in machine and transverse
direction (ASTM D1922)
A
TABLE 3 Polyethylene Tube Sizes for Push-On Joint Pipe
Nominal Pipe Diameter, in. Recommended Polyethylene
B
Flat Tube Width, in. [cm]
3 14 [36]
4 14 [36]
6 16 [41]
8 20 [51]
10 24 [61]
12 27 [69]
14 30 [76]
16 34 [86]
18 37 [94]
20 41 [104]
24 54 [137]
30 67 [170]
36 81 [206]
42 81 (206)
48 95 [241]
54 108 [274]
60 108 [274]
64 121 [307]
A
These wrap sizes should work with most push-on joint pipe and fitting bell sizes.
Where bell circumferences are larger than the sheet sizes shown, the bell areas
should be carefully wrapped with cut film sections, effectively lapping and securing
cut edges as necessary; or, alternatively, sufficiently large tube or sheet film to
effectively cover these joints should be ordered.
B
For flat sheet polyethylene, see 5.3.3.
It is also recommended that circumferential wraps of tape or plastic tie straps be placed at 2 ft [0.6 m] intervals along the barrel
of the pipe to help minimize the space between the polyethylene and the pipe.
5.2 Polyethylene Installers—The polyethylene encasement shall be installed by personnel trained or experienced in the proper
application of the encasement as described in this standard. At all times during construction of the pipeline, precautions shall be
taken to prevent damage to the encasement film.
5.3 Methods of Installation—This practice includes three different methods for the installation of polyethylene encasement.
Method A and B are for use with polyethylene tubes and Method C is for use with polyethylene sheets.
5.3.1 Method A (see Fig. 1):
5.3.1.1 Cut the polyethylene tube to a length approximately 2 ft [0.6 m] longer than the length of the pipe section. Slip the tube
around the pipe, centering it to provide a 1-ft [0.3-m] overlap on each adjacent pipe section, and bunching it accordion fashion
lengthwise until it clears the pipe ends.
5.3.1.2 Lower the pipe into the trench and make up the pipe joint with the preceding section of pipe. A shallow bell hole must
be made at joints to facilitate installation of the polyethylene tube.
5.3.1.3 After assembling the pipe joint, make the overlap of the polyethylene tube. Pull the bunched polyethylene from the
preceding length of pipe, slip it over the end of the new length of pipe, and secure in place. Then slip the end of the polyethylene
A674 − 10 (2014)
FIG. 1 Method A
from the new pipe section over the end of the first wrap until it overlaps the joint at the end of the preceding length of pipe. Secure
the overlap in place. Take up the slack width at the top of the pipe as shown in Fig. 2, to make a snug, but not tight, fit along the
barrel of the pipe, securing the fold at quarter points.
5.3.1.4 Repair any rips, punctures, or other damage to the polyethylene with adhesive tape or with a short length of polyethylene
tube cut open, wrapped around the pipe, and secured in place. Proceed with installation of the next section of pipe in the same
manner.
5.3.2 Method B (see Fig. 3):
5.3.2.1 Cut the polyethylene tube to a length approximately 1 ft [0.3 m] shorter than the length of the pipe section. Slip the tube
around the pipe, centering it to provide 6 in. [150 mm] of bare pipe at each end. Make the polyethylene snug, but not tight, as
shown in Fig. 2; secure ends as described in 5.1.
5.3.2.2 Before making up a joint, slip a 3-ft [0.9-m] length of polyethylene tube over the end of the preceding pipe section,
bunching it accordion fashion lengthwise. Alternatively, place a 3-ft [0.9 m] length of polyethylene sheet in the trench under the
joint to be made. After completing the joint, pull the 3-ft length of polyethylene over or around the joint, overlapping the previously
installed on each adjacent section of pipe by at least 1 ft [0.3 m]; make snug and secure each end as described in 5.1. A shallow
bell hole must be made at joints to facilitate installation of the polyethylene tube or sheet.
5.3.2.3 Repair any rips, punctures, or other damage to the polyethylene as described in 5.6. Proceed with installation of the next
section of pipe in the same manner.
5.3.3 Method C (see Fig. 4):
5.3.3.1 Flat sheet polyethylene shall have a minimum width twice the flat tube width shown in Table 3.
5.3.3.2 Cut the polyethylene sheet to a length approximately 2 ft [0.6 m] longer than the length of pipe section. Center the cut
length to provide a 1-ft [0.3-m] overlap on each adjacent pipe section, bunching it until it clears the pipe ends. Wrap the
polyethylene around the pipe so that it overlaps circumferentially over the top quadrant of the pipe. Secure the cut edge of
polyethylene sheet at approximately 3-ft [0.9-m] intervals along the pipe length.
5.3.3.3 Lower the wrapped pipe into the trench and make up the pipe joint with the preceding section of pipe. A shallow bell
hole must be made at joints to facilitate installation of the polyethylene. After completing the joint, make the overlap as described
in 5.1.
5.3.3.4 Repair any rips, punctures, or other damage to the polyethylene as described in 5.6. Proceed with installation of the next
section of pipe in the same manner.
5.4 Pipe-Shaped Appurtenances—Bends, reducers, offsets, and other pipe-shaped appurtenances shall be covered with
polyethyl
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