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SM
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AWWA C604-06(First Edition)
Installation of Steel Water Pipe4 In. (100 mm) and Larger
Effective date: Dec. 1, 2007.First edition approved by AWWA
Board of Directors: Feb. 12, 2006.This edition approved: Feb. 12,
2006.
Copyright 2007 American Water Works Association. All Rights
Reserved.
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ii
AWWA StandardThis document is an American Water Works
Association (AWWA) standard. It is not a specification. AWWA
standardsdescribe minimum requirements and do not contain all of
the engineering and administrative information normallycontained in
specifications. The AWWA standards usually contain options that
must be evaluated by the user of thestandard. Until each optional
feature is specified by the user, the product or service is not
fully defined. AWWA publicationof a standard does not constitute
endorsement of any product or product type, nor does AWWA test,
certify, or approveany product. The use of AWWA standards is
entirely voluntary. AWWA standards are intended to represent a
consensusof the water supply industry that the product described
will provide satisfactory service. When AWWA revises or
withdrawsthis standard, an official notice of action will be placed
on the first page of the classified advertising section of
JournalAWWA.The action becomes effective on the first day of the
month following the month of Journal AWWA publication of
theofficial notice.
Science and TechnologyAWWA unites the drinking water community
by developing and distributing authoritative scientific and
technologicalknowledge. Through its members, AWWA develops industry
standards for products and processes that advance publichealth and
safety. AWWA also provides quality improvement programs for water
and wastewater utilities.
All rights reserved. No part of this publication may be
reproduced or transmitted in any form or by any means, electronicor
mechanical, including photocopy, recording, or any information or
retrieval system, except in the form of brief excerptsor quotations
for review purposes, without the written permission of the
publisher.
Copyright 2007 by American Water Works AssociationPrinted in
USA
Copyright 2007 American Water Works Association. All Rights
Reserved.
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iii
Committee Personnel
The Steel Water Pipe-Manufacturers Technical Advisory Committee
(SWPMTAC)Task Force for Development and Maintenance of AWWA C604,
which developed thisstandard, had the following personnel at the
time:
Nash Williams, Chair
H.H. Bardakjian, Ameron Concrete & Steel Pipe,
Rancho Cucamonga, Calif. (AWWA)
M. Bauer, Tnemec Company, North Kansas City, Mo. (AWWA)
R.J. Card, Brico Industries Inc., Atlanta, Ga. (AWWA)
R.R. Carpenter, American Cast Iron Pipe Company, Birmingham,
Ala. (AWWA)
K. Clark, Mueller Company, Decatur, Ill. (AWWA)
R.R. Collins, JCM Industries, Nash, Texas (AWWA)
D. Eaton, Romac Industries Inc., Bothell, Wash. (AWWA)
R.W. Geary, Tek-Rap Inc., Houston, Texas (AWWA)
J.H. Hoff, Hoff Company Inc., Tulsa, Okla. (AWWA)
B.D. Keil, Continental Pipe Manufacturing Company,
Pleasant Grove, Utah (AWWA)
C.R. McCormick, Conduit Fabricator Inc., Redding, Calif.
(AWWA)
S. McMillen, Continental Manufacturing Inc., Nacogdoches, Texas
(AWWA)
M. Mintz, M-Square Associates Inc., Valley Stream, N.Y.
(AWWA)
A. Parrish, CAB Incorporated, Oakwood, Ga. (AWWA)
G. Ruchti, American Spiral Weld Pipe Company, Punta Gorda, Fla.
(AWWA)
R.N. Satyarthi, Baker Coupling Co. Inc., Los Angeles, Calif.
(AWWA)
D.A. Scott, Scapa Tapes North America, Calgary, Alta. (AWWA)
K.L. Shaddix, Smith-Blair Inc., Texarkana, Texas (AWWA)
H.R. Stoner, Consultant, North Plainfield, N.J. (AWWA)
B. Stott, Metrotect Ltd., West Yorkshire, England (AWWA)
M. Topps, Glynwed Pipe Systems, Hixson, Tenn. (AWWA)
B. Vanderploeg, Northwest Pipe Company, Portland, Ore.
(AWWA)
Copyright 2007 American Water Works Association. All Rights
Reserved.
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iv
D.R. Wagner, Consultant, St. Louis, Mo. (AWWA)
N. Williams, National Welding Corporation, Midvale, Utah
(AWWA)
J.A. Wise, Canus Industries Inc., Port Coquitlam, B.C.
(AWWA)
The Standards Committee on Steel Pipe, which reviewed and
approved this standard,had the following personnel at the time of
approval:
George J. Tupac, ChairJohn H. Bambei Jr., Vice-Chair
Dennis Dechant, Secretary
General Interest Members
E. Bakall, Consulting Engineer, Tustin, Calif. (AWWA)
W.R. Brunzell, Brunzell Associates Ltd., Skokie, Ill. (AWWA)
R.L. Coffey, Kirkham Michael Consulting Engineers, Omaha, Neb.
(AWWA)
H.E. Dunham, Montgomery Watson, Bellevue, Wash. (AWWA)
K.G. Ferguson,* Montgomery Watson, Las Vegas, Nev. (AWWA)
S.N. Foellmi, Black & Veatch LLP, Irvine, Calif. (AWWA)
J.W. Green, Alvord Burdick & Howson, Lisle, Ill. (AWWA)
K.D. Henrichsen, HDR Engineering Inc., Denver, Colo. (AWWA)
M.B. Horsley,* Black & Veatch LLP, Overland Park, Kan.
(AWWA)
J.K. Jeyapalan, Engineering Consultant, New Milford, Conn.
(AWWA)
R. Ortega, Lockwood Andrews & Newnam Inc., Houston, Texas
(AWWA)
A.E. Romer, Boyle Engineering Corporation, Newport Beach, Calif.
(AWWA)
H.R. Stoner, Consultant, North Plainfield, N.J. (AWWA)
C.C. Sundberg, CH2M Hill Inc., Bellevue, Wash. (AWWA)
G.J. Tupac, G.J. Tupac & Associates, Pittsburgh, Pa.
(AWWA)
J.S. Wailes, Standards Engineer Liaison, AWWA, Denver, Colo.
(AWWA)
L.W. Warren, Seattle, Wash. (AWWA)
*Alternate
Liaison, nonvoting
Copyright 2007 American Water Works Association. All Rights
Reserved.
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vW.R. Whidden, Post Buckley Schuh & Jernigan, Orlando, Fla.
(AWWA)
Producer Members
H.H. Bardakjian, Ameron Concrete & Steel Pipe,
Rancho Cucamonga, Calif. (AWWA)
R.J. Card, Brico Industries Inc., Atlanta, Ga. (AWWA)
R.R. Carpenter, American Cast Iron Pipe Company, Birmingham,
Ala. (MSS)
D. Dechant, Northwest Pipe Company, Denver, Colo. (AWWA)
J.E. Hagelskamp,* American Cast Iron Pipe Company, Maitland,
Fla. (AWWA)
B.D. Keil, Continental Pipe Manufacturing Company, Pleasant
Grove, Utah (SPFA)
J.L. Luka, American SpiralWeld Pipe Company, Columbia, S.C.
(AWWA)
B. Vanderploeg,* Northwest Pipe Company, Portland, Ore.
(AWWA)
J.A. Wise, Canus Industries Inc., Port Coquitlam, B.C.
(AWWA)
User Members
G.A. Andersen, New York City Bureau of Water Supply, Corona,
N.Y. (AWWA)
J.H. Bambei Jr., Denver Water Department, Denver, Colo.
(AWWA)
D.W. Coppes, Massachusetts Water Resources Authority, Chelsea,
Mass. (NEWWA)
R.V. Frisz, US Bureau of Reclamation, Denver, Colo. (USBR)
T.R. Jervis, Greater Vancouver Regional District, Burnaby, B.C.
(AWWA)
T.J. Jordan, Metropolitan Water District of Southern
California,
La Verne, Calif. (AWWA)
T.A. Larson, Tacoma Water Division, Tacoma, Wash. (AWWA)
A.L. Linard, Los Angeles Department of Water & Power,
Los Angeles, Calif. (AWWA)
G.P. Stine, San Diego County Water Authority, San Diego, Calif.
(AWWA)
J.V. Young, EPCOR Water Services Inc., Richmond, B.C. (AWWA)
*Alternate
Copyright 2007 American Water Works Association. All Rights
Reserved.
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Copyright 2007 American Water Works Association. All Rights
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vii
Contents
All AWWA standards follow the general format indicated
subsequently. Some variations from this formatmay be found in a
particular standard.
SEC. PAGE SEC. PAGE
Foreword
I Introduction........................................ix
I.A History of Standard ............................ix
I.B Discussion...........................................ix
I.C Acceptance ..........................................ix
II Special Issues.......................................xi
II.A Application .........................................xi
III Use of This Standard ..........................xi
III.A Purchaser Options and Alternatives ....xi
III.B Modification to Standard...................xii
IV Major Revisions .................................xii
V Comments .........................................xii
Standard
1 General
1.1 Scope
...................................................1
1.2 Purpose
................................................2
1.3 References ............................................2
1.4 Definitions...........................................3
1.5 Preconstruction Planning.....................6
1.6 Permeation...........................................7
2 Inspection, Unloading, Handling,
and Storage
2.1 Inspection ............................................7
2.2 Unloading, Handling, and Storage ......7
3 Installation
3.1 Alignment and Grade ..........................8
3.2 Trench Construction ...........................9
3.3 Pipe Installation.................................12
3.4 Joint Assembly and Testing ...............13
3.5 Fitting Installation .............................25
3.6 Thrust Restraint.................................27
3.7 Backfilling..........................................27
3.8 Flushing .............................................30
4 Hydrostatic Field Testing
4.1 Pressure and Leakage Test .................31
5 Disinfection.......................................32
6 Highway and Railroad Crossings
6.1 Casing Pipe........................................32
6.2 Carrier Pipe .......................................33
7 Subaqueous Crossings
7.1 Subaqueous Installations ....................33
Figures
1 Typical O-Ring Gasket Assembly ......14
2 Typical Installation of Pipe With
Gasketed Bell-and-Spigot Joints......15
3 Typical Installation of Pipe With
Welded Bell-and-Spigot Joints........17
Copyright 2007 American Water Works Association. All Rights
Reserved.
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viii
SEC. PAGE SEC. PAGE
4 Joint Deflection .................................18
5 Pipe Bedding ................................... 29
Copyright 2007 American Water Works Association. All Rights
Reserved.
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ix
Foreword
This foreword is for information only and is not a part of AWWA
C604.
I. Introduction.
I.A. History of Standard. This standard pertains to the
in-ground installation
of steel pipelines for use in the distribution and transmission
of water, air, and other
products in water system facilities. It has been prepared by the
AWWA Standards
Committee on Steel Pipe, initially formed as Committee A7A in
1939. At that time,
the Steel Water Pipe Manufacturers Technical Advisory Committee
was organized as
a subsidiary group to function as a source of technical
information for the parent
committee. Committee A7A and its successors, Committee 8310D and
the AWWA
Standards Committee on Steel Pipe have assumed responsibility
for all AWWA
standards and manuals pertaining to steel pipe, fittings,
linings and coatings, field
installations, and related items.
In 1996 the AWWA Standards Council directed the Standards
Committee on
Steel Pipe to develop a standard for the installation of steel
pipelines and their
appurtenances used in water treatment or conveying facilities.
This standard,
AWWA C604, is the first steel pipe installation standard
developed by AWWA.
I.B. Discussion. AWWA C604 includes all types of steel pipe 4
in. (100 mm)
in diameter and larger typically used in the water industry,
regardless of pipe
manufacturing source. With adequate quality assurance, pipe
manufactured in a
fabricators shop or in a steel-pipe mill is suitable for water
utility service. Pipe
produced in a fabricators shop or pipe mill for installation in
accordance with
AWWA C604 shall meet the stringent design, quality control, and
testing
requirements of AWWA Manual M11 and AWWA C200. Shop and
mill-fabricated
pipe made from materials and in accordance with the quality
control measures
stipulated in AWWA Manual M11 and AWWA C200 will ensure
fabricated pipe of
high quality.
I.C. Acceptance. In May 1985, the US Environmental Protection
Agency
(USEPA) entered into a cooperative agreement with a consortium
led by NSF
International (NSF) to develop voluntary third-party consensus
standards and a
certification program for all direct and indirect drinking water
additives. Other
members of the original consortium included the American Water
Works Association
Research Foundation (AwwaRF) and the Conference of State Health
and Environ-
Copyright 2007 American Water Works Association. All Rights
Reserved.
-
xmental Managers (COSHEM). The American Water Works Association
(AWWA)
and the Association of State Drinking Water Administrators
(ASDWA) joined later.
In the United States, authority to regulate products for use in,
or in contact with,
drinking water rests with individual states.* Local agencies may
choose to impose
requirements more stringent than those required by the state. To
evaluate the health
effects of products and drinking water additives from such
products, state and local
agencies may use various references, including
1. An advisory program formerly administered by USEPA, Office of
Drinking
Water, discontinued on Apr. 7, 1990.
2. Specific policies of the state or local agency.
3. Two standards developed under the direction of NSF, NSF/ANSI
60,
Drinking Water Treatment ChemicalsHealth Effects, and NSF/ANSI
61, Drink-
ing Water System ComponentsHealth Effects.
4. Other references, including AWWA standards, Food Chemicals
Codex, Water
Chemicals Codex, and other standards considered appropriate by
the state or local
agency.
Various certification organizations may be involved in
certifying products in
accordance with NSF/ANSI 61. Individual states or local agencies
have authority to
accept or accredit certification organizations within their
jurisdiction. Accreditation
of certification organizations may vary from jurisdiction to
jurisdiction.
Annex A, Toxicology Review and Evaluation Procedures, to
NSF/ANSI 61
does not stipulate a maximum allowable level (MAL) of a
contaminant for substances
not regulated by a USEPA final maximum contaminant level (MCL).
The MALs of
an unspecified list of unregulated contaminants are based on
toxicity testing
guidelines (noncarcinogens) and risk characterization
methodology (carcinogens).
Use of Annex A procedures may not always be identical, depending
on the certifier.
AWWA C604-06 does not address additives requirements. Thus,
users of this
standard should consult the appropriate state or local agency
having jurisdiction in
order to
*Persons outside the United States should contact the
appropriate authority having jurisdiction.
NSF International, 789 North Dixboro Road, Ann Arbor, MI
48105.
American National Standards Institute, 25 West 43rd Street,
Fourth Floor, New York, NY 10036.
Both publications available from National Academy of Sciences,
500 Fifth Street, NW,Washington, DC 20001.
Copyright 2007 American Water Works Association. All Rights
Reserved.
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xi
1. Determine additives requirements, including applicable
standards.
2. Determine the status of certifications by all parties
offering to certify
products for contact with, or treatment of, drinking water.
3. Determine current information on product certification.
II. Special Issues.
II.A. Application. AWWA C604-06, Standard for Installation of
Steel Water
Pipe4 In. (100 mm) and Larger, can be used as a reference when
making
extensions to existing distribution or transmission systems or
when constructing new
distribution or transmission systems using steel pipe. It is not
the intent for this
standard to be used as a contract document, but it may be used
as a reference in
contract documents. It is based on a consensus of the committee
on the minimum
practice consistent with sound, economical service under normal
conditions, and its
applicability under any circumstances must be reviewed by a
responsible engineer.
The standard is not intended to preclude the manufacture,
marketing, purchase, or
the use of any product, process, or procedure.
III. Use of This Standard. AWWA has no responsibility for the
suitability or
compatibility of the provisions of this standard to any intended
application by any
user. Accordingly, each user of this standard is responsible for
determining that the
standard's provisions are suitable for and compatible with that
users intended
application.
III.A. Purchaser Options and Alternatives. The following items
should be
included in the purchasers specifications.
Considerable supplemental information is required in conjunction
with the use
of this standard, including, but not limited to, contract
documents consisting of
detailed plans and specifications. The specifications should
cover, as a minimum,
detailed instructions pertaining to all references in this
standard to as specified and
in accordance with the specifications. In addition, the
purchaser shall provide
specific supplementary information to the contract documents
regarding the
following:
1. Pipe design criteria and type of pipe ends.
2. Pipe laying schedules, line drawings, markings,
appurtenances, vaults, valves,
and existing utilities.
3. Pipe bedding specification and drawing details.
4. Inspection for pipe joints, protective coatings and linings,
and pipe zone
compaction.
Copyright 2007 American Water Works Association. All Rights
Reserved.
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xii
5. Surface restoration.
6. Special handling requirements.
III.B. Modification to Standard. Any modification to the
provisions, defini-
tions, or terminology in this standard must be provided in the
purchasers
specifications.
IV. Major Revisions. This is the first edition of this
standard.
V. Comments. If you have any comments or questions about this
standard,
please call the AWWA Volunteer & Technical Support Group at
303.794.7711, FAX
303.795.7603, write to the group at 6666 W. Quincy Avenue,
Denver, CO 80235-
3098, or e-mail at [email protected].
Copyright 2007 American Water Works Association. All Rights
Reserved.
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1AWWA Standard
AWWA C604-06(First Edition)
Installation of Steel Water Pipe
4 In. (100 mm) and Larger
SECTION 1: GENERAL
Sec. 1.1 Scope
This standard provides the field installation guidelines for
buried steel water
pipe, 4 in. (100 mm)* and larger, and their appurtenances.
The information contained in this standard is intended to be
used as a guide to
assist in the installation of steel water pipe. Whenever the
methods contained herein
conflict with those of the contract documents and/or the
purchaser, the contract
documents and/or purchaser should be followed.
1.1.1 Conditions which may require additional considerations.
Ins ta l l a t ions
that require special attention, techniques, and materials are
not covered. Some of
these installations are
1. Piping through rigid walls.
*Metric conversions given in this standard are direct
conversions of US customary units and are notthose specified in the
International Organization for Standardization (ISO) standards.
Copyright 2007 American Water Works Association. All Rights
Reserved.
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2 AWWA C604-06
2. Piping on supports above or below ground, connected to
appurtenances.
3. Piping requiring insulation.
4. Treatment plant or pump-station piping.
5. Industrial piping.
6. Piping through geologically hazardous areas.
7. Piping in high-density-stray-current environments.
8. Piping through corrosive soil.
9. Piping through unstable soil.
10. Piping subjected to excessive loads.
Sec. 1.2 Purpose
This standard is intended to cover typical pipeline construction
practices that
are deemed adequate for the satisfactory installation of steel
water pipe and
appurtenances. Individual project requirements can vary
substantially and should
always be thoroughly reviewed prior to bidding or construction
startup. For this
reason, some practices discussed in this standard may not be
suitable for all project
conditions, and, in some cases specialized installation
techniques may be required
that are beyond the scope of this standard.
Sec. 1.3 References
This standard references the following documents. In their
latest editions, the
referenced documents form a part of this standard to the extent
specified herein. In
any case of conflict, the requirements of this standard shall
prevail.
AASHTO T99*Moisture Density Relations of Soils Using a 5.5-lb
(2.5-kg)
Rammer and a 12-in. (305-mm) Drop.
ANSI/AWWA C500Metal-Seated Gate Valves for Water Supply
Service.
ANSI/AWWA C509Resilient-Seated Gate Valves for Water Supply
Service.
ANSI/AWWA C651Disinfecting Water Mains.
AWWA Manual M3, Safety Practices for Water Utilities, AWWA,
Denver, Colo.
(1990).
The reader is referred to the following standards for additional
information on
the use or limitations of specific products.
*American Association of State Highway and Transportation
Officials, 444 North Capitol Street N.W.,Suite 249, Washington, DC
20001-1512.
Copyright 2007 American Water Works Association. All Rights
Reserved.
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INSTALLATION OF STEEL WATER PIPE4 IN. (100 MM) AND LARGER 3
ANSI/AWWA AWWA C203Coal-Tar Protective Coatings and Linings
for
Steel Water PipelinesEnamel and TapeHot-Applied.
ANSI/AWWA C205CementMortar Protective Lining and Coating for
Steel
Water Pipe4 In. (100 mm) and LargerShop Applied.
ANSI/AWWA C206Field Welding of Steel Water Pipe.
ANSI/AWWA C207Steel Pipe Flanges for Waterworks ServiceSizes 4
In.
Through 144 In. (100 mm Through 3,600 mm).
ANSI/AWWA C208Dimensions for Fabricated Steel Water Pipe
Fittings.
ANSI/AWWA C209Cold-Applied Tape Coatings for the Exterior of
Special
Sections, Connections, and Fittings for Steel Water
Pipelines.
ANSI/AWWA C210Liquid Epoxy Coating Systems for the Interior
and
Exterior of Steel Water Pipelines.
ANSI/AWWA C216Heat-Shrinkable Cross-Linked Polyolefin Coatings
for
the Exterior of Special Sections, Connections, and Fittings for
Steel Water Pipelines.
ANSI/AWWA C217Petrolatum and Petroleum Wax Tape Coatings for
the
Exterior of, Connections and Fittings for Steel Water
Pipelines.
ANSI/AWWA C219Bolted Sleeve-Type Couplings for Plain-End
Pipe.
ANSI/AWWA C222Polyurethane Coatings for the Interior and
Exterior of
Steel Water Pipe and Fittings.
ANSI/AWWA C504Rubber-Seated Butterfly Valves.
ANSI/AWWA C800Underground Service Line Valves and Fittings.
OSHA 29 CFR 1986*Health Regulations for Construction.
AWWA M11Steel Water Pipe: A Guide for Design and
Installation.
AWS D1.1Structural Welding Code.
Sec. 1.4 Definitions
In this standard, the following definitions shall apply:
1.4.1 Bevel: The angle formed between the prepared edge of a
pipe end and
a plane perpendicular to the longitudinal axis of the pipe.
Bevels are generally used
for butt welding of pipe ends.
*Occupational Safety and Health Administration, Code of Federal
Regulations; available fromGovernment Printing Office, 720 N. Main,
Pueblo, CO 81003.
American Welding Society, 550 N.W. LeJeune Road, Miami, FL
33126-5699.
Copyright 2007 American Water Works Association. All Rights
Reserved.
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4 AWWA C604-06
1.4.2 Utility location service: The cooperative organization of
major utilities
to provide services for the location and safe construction
practices surrounding their
respective utilities. These utilities often provide a site
representative during
construction when deemed necessary by the utility.
1.4.3 Butt joint: A pipe joint in which the two pipe ends are in
the same
plane and do not overlap. This joint configuration is commonly
beveled and usually
includes a backup ring on the side opposite of which welding is
to be performed.
1.4.4 Dewatering: The removal of water in and around
construction
operations. This usually pertains to underground water within
construction zones,
which can adversely affect the construction activities.
1.4.5 Fillet weld: A weld of approximately triangular cross
section, the throat
of which lies in a plane disposed approximately 45 with regard
to the surface of the
parts joined. The size of the fillet weld is expressed in terms
of the width, in inches,
of one of its adjacent fused legs (the shorter leg, if
unequal).
1.4.6 Grade: The elevation of a structure or pipeline invert
(bottom of the
flowline) at a specific location. This elevation is usually
measured relative to
established survey points at the project.
1.4.7 Bell-and-spigot or lap joint: A circumferential joint in
which one of the
members joined overlaps the other.
1.4.8 Manufacturer: The party or firm that manufactures or
supplies the
products covered by this standard.
1.4.9 Mechanical cutting: The severing of materials by use of a
thin flat
blade having a continuous line of teeth on its edge or
high-speed abrasive disk.
1.4.10 Miter: The angle between the cut of a pipe end and a line
drawn
perpendicular to the longitudinal axis of the pipe. Miters are
used to fabricate elbows
and to facilitate pipe laying at changes in horizontal or
vertical alignment.
1.4.11 Nominal diameter or size: The commercial designation or
dimension
by which pipe is designated for simplicity. Commonly, it is the
finished inside
diameter after lining.
1.4.12 Nominal wall thickness: The thickness named or given, as
distin-
guished from the actual or measured thickness.
1.4.13 Nominal weight per foot (for bare pipe): The theoretical
weight, per
foot, calculated from the nominal wall thickness, as
distinguished from the actual and
measured weight per foot of the finished pipe. Unit weights of
0.284 lb per cubic
Copyright 2007 American Water Works Association. All Rights
Reserved.
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INSTALLATION OF STEEL WATER PIPE4 IN. (100 MM) AND LARGER 5
inch for steel sheet or 490 lb per cubic foot for steel plate
shall be used when
calculating weight per foot.
1.4.14 Pipe bedding: The material immediately under the pipeline
and by
which the pipeline is supported. This material is usually of a
specific description and
may simply be the reuse of the originally excavated
material.
1.4.15 Plain-end pipe: Pipe that is not threaded, belled, or
otherwise given a
special end configuration.
1.4.16 Plans: Drawings normally prepared by an engineer employed
or
retained by the purchaser system-operator entity showing the
location and details for
the construction of the pipeline and appurtenances.
1.4.17 Plasma-arc cutting: An arc-cutting process that severs
metal by
melting a localized area with a constricted arc and removing the
molten material with
a high-velocity jet of hot, ionized gas blown at high speed from
the constricting
orifice.
1.4.18 Purchaser: The person, company, or organization that
purchases any
materials or work to be performed.
1.4.19 Random lengths: Pipe lengths as produced in a pipe mill,
to which no
special treatment is given to make the lengths uniform.
1.4.20 Root: That portion of a joint to be welded where the
members
approach closest to each other. In cross section, the root of a
joint may be a point, a
line, or an area.
1.4.21 Seamless pipe: Pipe without welds or filler metal, made
from solid
ingots, blooms, billets, or round bars that have been hot
pierced and then brought to
the desired size by hot rolling, hot drawing, or a combination
of both.
1.4.22 Select material: The native soil free of rocks, foreign
or organic
materials, and frozen earth.
1.4.23 Special section: Any piece of pipe other than a normal
full-length
straight section. This includes but is not limited to elbows,
personnel access sections,
short pieces, reducers, adapter sections with special ends, and
other nonstandard
sections.
1.4.24 Specifications: Detailed procedures and requirements
initiated by the
purchaser or designee, outlining methods of design, manufacture,
standards of
acceptability, methods of installation, or any other criteria
the purchaser deems
necessary for the procurement of the product required.
Installation specifications may
Copyright 2007 American Water Works Association. All Rights
Reserved.
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6 AWWA C604-06
incorporate this standard by reference, but should also include
specification
requirements for matters not covered by the standard.
1.4.25 Specified lengths: Sections of finished pipe, the length
dimensions of
which do not vary from a fixed figure specified by the purchaser
by more than the
tolerance set forth.
1.4.26 Supplier: The party who supplies material or services. A
supplier may
or may not be the manufacturer.
1.4.27 Trench zone: The area of excavation within which a
pipeline or
structure will be placed.
1.4.28 Underground utilities: Previously installed utilities
that are located
within the right-of-way of a pipeline or structure. These
utilities commonly include
gas, power, water, cable TV, sewer, fiber-optic cable, steam
lines, and telephone
lines.
Sec. 1.5 Preconstruction Planning
The installation of steel pipelines usually involves multiple
suppliers and
subcontractors that have varying preparation requirements. For
this reason a
preconstruction meeting is strongly recommended to schedule the
critical path
aspects of all involved parties. In particular, pipe and valve
materials are usually
manufactured to fit specific locations of the project and often
require an extended
lead time for the purchase of raw material, drawing preparation,
and drawing
approvals that must precede construction activities. Any
preconstruction planning
meeting initiated by the purchaser should include all essential
suppliers and
subcontractors. During the meeting a schedule should be prepared
that is agreeable
to all parties and provides float for operations subject to
potential delays. All parties
elaborate on their respective preparations, such as procurement
of materials,
preparation of drawings, and submittals. The constructor shall
be required to provide
the starting location and direction of construction. Care should
be taken when
preparing the construction schedule as later changes in
construction plans may affect
shop drawings, laying schedules, delivery dates, and other
parties. Detailed shop
drawings must be approved by the constructor and purchaser prior
to pipe
production.
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INSTALLATION OF STEEL WATER PIPE4 IN. (100 MM) AND LARGER 7
Sec. 1.6 Permeation
The selection of materials is critical for water service and
distribution piping in
locations where the pipe is likely to be exposed to significant
concentrations of
pollutants composed of low-molecular-weight petroleum products,
organic solvents,
or their vapors. Documented research has shown that pipe
materials such as
polyethylene, polybutylene, polyvinyl chloride, and asbestos
cement, as well as
elastomers, such as those used in jointing gaskets and packing
glands, may be subject
to permeation. If a water pipe must pass through such a
contaminated area or an area
subject to contamination, consult with the manufacturer
regarding permeation of
pipe joints coatings, and so on, before selecting materials for
use in that area.
SECTION 2: INSPECTION, UNLOADING, HANDLING, AND STORAGE
Sec. 2.1 Inspection
2.1.1 Pipe inspection at the plant. All materials shall be
subject to inspection
and acceptance at the manufacturers plant. Acceptance criteria
shall be based on
criteria agreed to by the purchaser and constructor in
accordance with the contract
documents.
2.1.2 Inspection on delivery. All pipe and appurtenances are
subject to
inspection at the point of delivery. Material found to be
defective because of
manufacture or damage in shipment shall be rejected or recorded
on the bill of
lading. There shall be agreement regarding any necessary
repairs. These repairs shall
be made and the purchaser shall monitor the repairs prior to
installation.
Sec. 2.2 Unloading, Handling, and Storage
Care shall be exercised when unloading, handling, and storing
pipe. Steel pipe
is generally manufactured in lengths exceeding 20 ft (6 m),
which may warrant the
use of a two-point lifting method for proper and safe handling.
Nylon or protected
slings at least 4 in. (100 mm) wide shall be used to handle
coated pipe. Cables,
chains, ropes, or other equipment that is likely to damage pipe
coatings shall not be
used.
Coated pipe shall be handled, stored, and shipped in a manner
that will prevent
damage to the coating. If the coating is damaged during
handling, storage, or
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8 AWWA C604-06
shipping, it shall be repaired with the original or a compatible
repair coating as
recommended by the coating manufacturer and in accordance with
the applicable
AWWA standard.
All pipe, fittings, and accessories shall be loaded and unloaded
carefully to avoid
impact or damage. Under no circumstances shall such material be
dropped.
2.2.1 Secure pipe. Before release of tie-downs around the pipe,
the loads shall
be checked to ensure the pipe is secure and stable.
2.2.2 Padding. Slings, hooks, and pipe tongs shall be padded and
used in
such a manner to prevent damage to the exterior surface or
internal lining of the
pipe, fittings, or related product.
2.2.3 Internal bracing. Usually pipe manufacturers provide
internal bracing
for handling and shipping purposes only. It is the
responsibility of the constructor to
maintain the bracing and ensure their need or adequacy during
installation. See also
Sec. 3.7.1.7.
2.2.4 Jobsite storage. Stored materials shall be kept safe from
damage. The
interior of all pipe, fittings, and other appurtenances shall be
kept reasonably free
from dirt or foreign matter at all times.
Coated pipe shall be protected from ultraviolet and weathering
damage as
recommended by the coating manufacturer. Coated pipe should
never be placed,
dragged, or rolled directly on the ground. Padded skids, earthen
berms, burlap sacks
filled with sand, and old car tires are some of the means to
adequately bunk the pipe
at the jobsite. Pipe shall not be stacked without proper
padding. Plastic caps on the
pipe ends for pipe that is cementmortar lined shall be left in
place until just prior
to installation.
SECTION 3: INSTALLATION
Sec. 3.1 Alignment and Grade
Pipelines shall be laid and maintained to lines and grades
established by the
contract documents for the project. Pipe laying in urban areas
shall not exceed 0.10 ft
(30 mm) in grade nor 3 in. (150 mm) in alignment unless
otherwise specified in the
contract documents. Valves and special fittings shall be
installed at the required
locations unless field conditions warrant otherwise and such
changes are agreed to by
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INSTALLATION OF STEEL WATER PIPE4 IN. (100 MM) AND LARGER 9
the purchaser and constructor. Valve-operating stems shall be
oriented in a manner to
allow proper operation.
3.1.1 Prior investigation. Prior to excavation, investigation
shall be made to
the extent necessary to determine the location of existing
underground utilities,
structures and conflicts. This will require the constructor to
contact the utility
location service for proper coordination and locating utilities.
In addition, care shall
be exercised during excavation to avoid damage to existing
structures, which may not
be identified by the utility location service. Special
precautions shall be taken when
the pipeline being installed crosses or is adjacent to a
facility that is cathodically
protected. When obstructions that are not shown on the contract
documents are
encountered during the progress of work and interfere so that an
alteration is
required, such alterations or deviation in line and grade or the
removal, relocation, or
reconstruction of the obstructions shall be performed in
accordance with the contract
documents.
3.1.2 Clearance. When crossing existing pipelines or other
structures,
alignment and grade shall be adjusted in accordance with the
contract documents.
Installed pipe and structures shall provide clearance as
required by federal, state or
provincial, and local regulations. Wherever possible, pipe and
structures shall have a
minimum clearance of 12 in. (300 mm) from existing pipelines or
structures to allow
for proper compaction.
Sec. 3.2 Trench Construction
The trench shall be excavated to the required alignment, depth,
and width
specified or shown on the contract documents and shall be in
conformance with all
federal, state or provincial, and local regulations for the
protection of workers.
3.2.1 Trench preparation. Trench preparation shall proceed in
advance of the
pipe installation. The amount of open trench length allowed is
limited by the
amount of nonbackfilled pipe according to Sec. 3.3, the contract
documents, and any
safety considerations (such as traffic, slope, etc.).
3.2.1.1 Discharges from trench dewatering pumps shall be
directed away from
the trench, in order not to affect trench stability, and shall
be in accordance with
federal, state, and local point discharge requirements.
3.2.1.2 Excavated material shall be placed in a manner that will
not obstruct
the work, endanger workers or the public, or obstruct sidewalks,
driveways,
roadways, and other structures. If obstruction of such
structures becomes necessary,
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10 AWWA C604-06
the constructor shall plan for alternate means to accommodate
the public. Placement
of excavated material shall be done in compliance with federal,
state or provincial,
and local regulations.
3.2.2 Pavement removal. Removal of pavement and road surfaces
shall be a
part of the trench excavation. The amount removed shall depend
on the width of
trench required for installation of the pipe, including safety
requirements and the
dimensions of the area into which valves, specials, manways, or
other structures will
be installed. Methods such as sawing, drilling, or chipping
shall be used to ensure the
breakage of pavement along straight lines.
3.2.3 Width. The width of the trench at the top of the pipe
shall be as
dictated by the contract documents or as necessitated by safety
requirements. In any
case, the trench width shall provide ample clearance to permit
the pipe to be installed
and joined properly and to allow the backfill to be placed in
accordance with the
contract documents. Trenches shall be of such extra width, when
required, to permit
the placement of sheeting, bracing, and appurtenances as
required by the safety
requirements of the agency having jurisdiction. In addition, the
trench width at the
bottom of the pipe will be governed by the space required for
compaction/
consolidation equipment, but never less than the outside
diameter of pipe plus 20 in.
(500 mm) (see Figure 5).
3.2.4 Depth. The trench shall be excavated to the specified
grade. The
trench bottom shall provide uniform support for the full length
of the pipe barrel,
except that a slight depression may be provided to facilitate
the removal of pipe slings
or other lifting tackle without damaging the pipe coating. Pipe
bedding and backfill
material shall be installed so as to avoid abrasion or other
damage to the coating on
the pipe.
3.2.5 Bell holes. Holes for the bells shall be provided at each
joint. Holes
shall be adequately sized for completing any external coatings,
but shall be no larger
than necessary to allow joint assembly. If the pipe joints are
welded or coupled, the
bell holes shall provide adequate clearance for welding or
assembly and subsequent
external coatings. A 24-in. (600-mm) clearance below or on the
sides of the pipe is
usually adequate for this purpose.
3.2.6 Rock conditions. If excavation of rock is necessary, all
rock shall be
removed to provide a clearance below and on each side of all
pipe, valves, and
fittings. The minimum clearance shall be 6 in. (150 mm) for pipe
with an outside
diameter (OD) up to 24 in. (600 mm) and 10 in. (250 mm) for pipe
with an OD
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INSTALLATION OF STEEL WATER PIPE4 IN. (100 MM) AND LARGER 11
greater than 24 in. (600 mm). When the excavation is completed,
a layer of
appropriate backfill material (see Sec. 3.7) shall be placed on
the bottom of the
trench to the previously mentioned depths, graded, and tamped.
These clearances
and bedding procedures shall also be observed for pieces of
concrete or masonry and
other debris or subterranean structures, such as masonry walls,
piers, or foundations
that may be encountered during excavation.
3.2.7 Previous excavations. Should the trench pass over a sewer
or other
previous excavation, the trench shall be sufficiently compacted
to provide support
equal to that of the native soil or conform to other regulatory
requirements in a
manner that will prevent damage to the existing
installation.
3.2.8 Blasting. Blasting for excavation shall be permitted only
after securing
approval(s) and establishing the hours of blasting as required
by the contract
documents. The blasting procedure, including protection of
existing utilities,
persons, and property, shall be in strict accordance with
federal, state or provincial,
and local regulations.
3.2.9 Protection of property. Trees, shrubs, fences, and all
other property and
surface structures and underground shall be protected during
construction unless
their removal is shown in the contract documents.
3.2.9.1 Temporary support, adequate protection, and maintenance
of all
underground and surface structures, drains, sewers, and other
obstructions encoun-
tered in the progress of the work shall be provided in
accordance with the contract
documents or applicable regulations.
3.2.10 Unsuitable subgrade material. When the subgrade is found
to include
ashes, cinders, refuse, organic material, or other unsuitable
material, such material
shall be removed at least to 6 in. (150 mm) below the bottom of
the pipe or to the
depth required by the contract documents. The removed material
shall be replaced
with clean, stable backfill material. The bedding shall be
compacted and graded so
that the pipe may be installed in accordance with Sec. 3.3.
3.2.11 Unstable subgrade. When the bottom of the trench or the
subgrade
consists of material that is unstable to such a degree that it
cannot be removed, a
foundation for the pipe and/or appurtenance shall be constructed
in accordance with
the contract documents.
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12 AWWA C604-06
Sec. 3.3 Pipe Installation
Proper implements, tools, and facilities shall be provided and
used for the safe
and convenient performance of the work. All pipe, fittings, and
valves shall be
lowered carefully into the trench by means of a backhoe or
crane, using nylon slings,
guide ropes, or other suitable tools or equipment, in such a
manner as to prevent
damage to the pipe, protective coatings, and linings. Pipe shall
not be dropped or
dumped into the trench. The trench shall be dewatered prior to
installation of the
pipe and maintained until the pipeline is substantially covered
as necessary to prevent
pipe from floating.
The length of pipe that may be installed prior to backfilling
shall not exceed
1,000 ft (330 m) or a length approved by the purchaser.
Backfilling for this purpose
is described as material covering the top of the pipe. If the
constructor chooses to
backfill between pipe joints, the exposed portion of the joint
area will be
accumulated toward the limit.
3.3.1 Examination of material. All pipe, fittings, coatings and
appurtenances
shall be examined carefully for damage and other defects
immediately before
installation. Defective materials shall be marked and held for
final disposition as
required by the contract documents.
3.3.2 Pipe ends. All deleterious materials shall be removed from
the ends of
each pipe. For bell- and spigot-pipe, the outside of the spigot
end and the inside of
the bell shall be wiped clean and dry so that it is free from
dirt, sand, grit, and other
foreign matter before the pipe is installed.
3.3.3 Pipe cleanliness. Foreign material shall be prevented from
entering the
pipe while it is being placed in the trench. No debris, tools,
clothing, or other
materials shall be allowed to accumulate during construction and
shall be promptly
removed as work progresses.
3.3.4 Direction of bells. It is common practice to lay welded
pipe joints with
the spigot facing the direction in which work is progressing;
however, this practice is
not mandatory. For gasketed pipe, common practice is to lay the
pipe joints with the
bell facing the direction in which work is progressing to
prevent debris from being
scooped into the bell. The direction of the bells is not
functionally related to the
direction of flow within the system.
3.3.5 Pipe end caps. When pipe laying is not in progress, the
open ends of
pipe may be required to be closed by a plug or other means as
specified. If utilized,
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INSTALLATION OF STEEL WATER PIPE4 IN. (100 MM) AND LARGER 13
the end caps shall remain in place until the trench work
proceeds. Care must be
taken to prevent pipe flotation should the trench fill with
water.
Sec. 3.4 Joint Assembly and Testing
Proper implements, tools, and facilities shall be provided and
used for the safe and
convenient performance of the work. The types of joints covered
in this standard include
gasketed, flanged, sleeve coupling, and welded joints, all of
which have specific
applications. The joint types required for a project will be
dictated by the contract
documents.
The joint assembly shall be coated with a compatible coating
according to the
coating manufacturers recommendations and the applicable AWWA
standard.
3.4.1 Gasketed joints. The gasketed joint design consists of a
bell-and-spigot
end configuration formed directly into the steel pipe cylinder
or attached to the steel
pipe cylinder. The spigot end includes a groove that retains an
O-ring gasket. The
gasket groove and the bell end of the mating pipe shall be
cleaned thoroughly. When
the spigot is inserted into the bell, the gasket compresses
between the steel surfaces to
form a watertight seal. Gasketed joints shall be assembled as
described in Sec. 3.4.1.1
and illustrated in Figures 1 and 2. Gaskets shall be designed
properly for the joint to
be assembled and shall be properly seated.
3.4.1.1 Pipe placement for gasketed joints. Mark the outside of
the pipe at
the quarter points for the full stab depth. This dimension is
provided as the length
on the joint detail drawings and typically ranges from 3 in. (75
mm) to 7 in.
(175 mm). Lift the pipe using the appropriate method. On steep
slopes it may be
advisable to use slings as chokers. Visually inspect the O-ring
gasket for any visible
defects, cuts, or tears. Before placing the gasket in the spigot
groove, apply a light
coat of vegetable-based pipe lubricant to the bottom of the
spigot groove. Stretch the
O-ring gasket over the pipe spigot end by hand or by using a
dull pry bar (to avoid
cuts or tears), and then carefully seat the gasket into the
O-ring groove on the spigot
(see Figure 1). After placement, tension relieve the gasket by
running a dull object,
such as a wooden dowel, between the gasket and the spigot
groove, around the pipe
circumference several times. Just prior to stabbing, apply a
light coat of vegetable-
based pipe lubricant to the spigot end exterior and the bell end
interior, being sure to
keep the joint clean. The spigot end shall be stabbed
approximately 1 in. (25 mm)
into the bell end, with the two mating pieces parallel to each
other (see Figure 2).
The spigot shall then be engaged the appropriate distance.
Small-diameter pipe
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14 AWWA C604-06
spigots can be pushed into the bell with a long bar.
Large-diameter pipe requires
additional power, such as from a jack, lever puller, or backhoe.
Before the pipe slings
are removed, drive the gasketed joint together. It can be driven
home as it is
suspended from the lifting boom, pushed home with the backside
of the bucket
(place a heavy timber between the bell end of pipe and the back
of the backhoe
bucket to protect the pipe from damage), or pulled with a winch.
As each length of
pipe is placed in the trench, the pipe shall be brought to the
correct line and grade.
After the joint is fully engaged, deflect the joint, if
required, within the prescribed
limits in Sec. 3.4.3 (see Figure 4) or the contract documents.
The pipe shall be
secured in place with approved backfill material.
3.4.1.2 Rubber gasket testing. After the pipe has been laid to
final grade, the
rubber gasketed joint shall be tested by a feeler gauge. This
test ensures that the
gasket has not rolled out of the groove, or "fish-mouthed.
Perform this test by
inserting a feeler gauge between the bell and spigot until
reaching the gasket.
Continue completely around the pipe circumference to ensure that
the gasket is
Figure 1 Typical O-ring gasket assembly
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INSTALLATION OF STEEL WATER PIPE4 IN. (100 MM) AND LARGER 15
Figure 2 Typical installation of pipe with gasketed
bell-and-spigot joints
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16 AWWA C604-06
continuous. Do not use a stabbing motion, as the feeler gauge
can pass through the
gap between the shoulder of the spigot and the inside of the
bell and possibly damage
the gasket. The only purpose of the feeler gauge test is to
determine whether the
gasket has rolled out of the groove during installation; it is
not performed to
determine the amount of clearance between the spigot and the
bell.
3.4.1.3 Repair of rubber gasket joints. If the gasket has
disengaged, the joint
shall be pulled apart, and the gasket shall be removed and
checked for any damage.
Reinstall the gasket, or if damaged, install a new gasket
following the procedure in
Section 3.4.1.1. Alternatively, if a pipe segment cannot be
removed, insert a rolled
steel round bar into the flare of the bell and seal weld the
round bar to the bell and
spigot.
3.4.2 Pipe placement for welded lap joints. Mark the outside of
the pipe at the
quarter points for the full stab depth. This dimension will be
provided with the
length of the joint detailed in the drawings and will typically
range from 2 in. (50
mm) to 3 in. (75 mm). Lift the pipe using a two-point lifting
method. On steep
slopes, it may be advisable to use the slings as chokers. Lower
the pipe segment, bell
end first, at an approximate 5 to 10 degree angle relative to
the previously laid pipe
segment. This will allow the bell edge to overlap the spigot (of
the previously laid
pipe) to the proper stab depth mark. On large-diameter pipe,
tack weld the joint
edge to provide a hinge that will guide the remainder of the
bell insertion as the pipe
is lowered (see Figure 3). The tack welds may remain as part of
the permanent weld
if the welder is properly qualified and the weldment meets the
requirements of ANSI/
AWWA C206 and the contract documents. Thermal stresses should
not be allowed
to accumulate due to the tack weld. Under certain circumstances,
some constructors
may choose to insert the spigot straight into the bell by
methods described in
Sec. 3.4.1.1. As each length of pipe is placed in the trench,
the joint shall be
assembled and checked for stab depth, and the pipe shall be
brought to correct line
and grade. After the joint is fully engaged, deflect the joint,
if required, within the
prescribed limits in Sec. 3.4.3 or the contract documents.
Proceed with the welding
of the joint in accordance with ANSI/AWWA C206 followed by any
required testing.
Upon successful weld testing, apply any required linings or
coatings. The pipe shall
be secured in place with approved backfill material.
3.4.3 Joint deflection. When it is necessary to deflect gasketed
or welded pipe
from a straight line in either the horizontal or vertical plane,
the amount of joint
deflection shall not exceed a 1 in. (25 mm) pull, measured at
the joint or in
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INSTALLATION OF STEEL WATER PIPE4 IN. (100 MM) AND LARGER 17
Figure 3 Typical installation of pipe with welded
bell-and-spigot joints
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18 AWWA C604-06
accordance with the contract documents (see Figure 4). The pull
is further described
as the dimension in which the pipe joint insertion varies when
measured from
opposite sides (180 degrees apart). This pull does not diminish
the minimum
required insertion dimension.
3.4.4 Flanged joints. Flanges commonly used for steel water pipe
are slip-on type
ring flanges. Flanges are designed for use with rubber or
nonasbestos gaskets (1/16 in.
[1.6 mm] or 1/8 in. [3.2 mm] thick). Both the size and type of
gasket material are
controlling factors in the design of bolted joints and, as such,
the AWWA M11
installation recommendations should be followed.
Regardless of the type of gasket being used or the materials of
construction,
certain basic procedures must be followed if the joint is to be
assembled, tested, and
put into operation easily. Regardless of the method used to
apply stress to the studs,
the following procedure should be followed carefully:
Figure 4 Joint deflection
= deflection angleS = joint deflection offsetL = laying lengthR
= radius of curve
R = L2tan 2
S
L
R
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INSTALLATION OF STEEL WATER PIPE4 IN. (100 MM) AND LARGER 19
1. Inspect the gasket seating surfaces. Look for tool marks,
scratches, or
pitting by corrosion, and make sure that the gasket seating
surface is proper for the
type of gasket being used.
2. Inspect the gasket. Look for possible defects or damage in
the gasket.
3. Lubricate all thread contact areas and nut facings. This step
is very
important.
4. Loosely install the fasteners on the lower half of the
flange. Insert the
gasket between the flange facings to allow the bolts to center
the gasket on the
assembly. Install the remaining bolts and nuts and tighten them
to a hand-tight or
snug condition.
5. Torque the bolts up to a maximum of 30 percent of the final
torque value
required, following the sequence recommended in AWWA M11. Number
the bolts
so that torquing requirements can be followed.
6. Repeat step 5, increasing the torque to 50 to 60 percent of
the final torque
value required.
7. Continue with the sequence of retorquing all fasteners to the
specified
torque value.
NOTE: For insulating flanges, refer to the manufacturers
recommendations.
3.4.5 Transition couplings. Transition couplings may be required
for joining
different types of pipe. Such transition devices are typically
available. When ordering,
the actual outside diameter of the pipe ends shall be given.
3.4.6 Tapping sleeves. Tapping sleeves are a means of making
branch
connections to existing pipelines. The procedures for proper
installation of tapping
sleeves shall follow the manufacturers recommendations.
3.4.7 Sleeve couplings. Sleeve couplings are used on pipelines
of all diame-
ters. The typical installation sequence for bolted, sleeve-type
couplings is provided in
ANSI/AWWA C219.
3.4.8 Split-sleeve coupling. Split-sleeve couplings are used on
pipelines of all
diameters. Follow the manufacturers recommendations for their
installation.
3.4.9 Welded joints. The need for welded joints will vary by
project and will
be dictated in the contract documents. Several types are common,
including lap,
butt, and butt-strap welded joints.
Welding shall meet the requirements of ANSI/AWWA C206 and the
contract
documents for the project. Shielded metal arc welding (SMAW), or
stick welding, is
the most common method used. Semiautomatic and automated welding
processes
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20 AWWA C604-06
are practical when a large number of welded joints are required.
These processes are
described in ANSI/AWWA C206.
In accordance with ANSI/AWWA C206, joint welding procedures,
welders and
welding operators shall be qualified under tests prescribed by
the American Welding
Society (AWS) D1.1 Structural Welding CodeSteel. Several common
joint welding
procedures outlined in AWS D1.1 are already considered
prequalified.
Preheating is required prior to welding when the steel
temperature is less than
32F (0C). For most mild steel applications where the steel wall
thickness is less than3/4 in. (19 mm) and using conventional
welding processes, preheating is required if
the metal temperature of the steel is less than 32F (0C) as
measured at any point
within 3 in. (75 mm) from the weld bead or 4 times the pipe wall
thickness,
whichever is greater. The specific preheating requirements will
vary depending on the
welding process, steel specification, steel thickness, and metal
temperature and should
be determined by using the AWS D1.1 preheat tables or Annex
equations.
The pipe shall be left bare a sufficient distance back from the
ends to prevent
the heat produced during welding from damaging the protective
coatings and to
prevent the coating from contaminating the in-process weld. In
addition, a protective
cover shall be draped over the pipe near the vicinity of welding
if further protection
is required. Field welding in the interior of steel pipe is
ordinarily limited to 36-in.
(900-mm) or larger pipe, to provide for access and egress. When
personnel are
working inside, ventilation shall be provided in strict
accordance with federal, state or
provincial, and local regulations.
Wire brushing is usually sufficient to remove any dirt or light
rust to prepare the
surface for welding. Small tack welds can be used to hold the
pipe in position for
welding, provided the tacks are sound and meet the requirements
of AWWA C206.
The number of weld passes needed to complete the joint is a
function of the steel
wall thickness, the type of joint, and the type of welding.
3.4.9.1 Welded lap joints. Welded lap joints are frequently used
when an
economical method of joint restraint is necessary or for
diameters greater than can be
manufactured for a gasketed joint. There are several welding
configurations for the
lap joint. The lap weld can be required on either the inside or
outside of the pipe
joint. Sometimes a lighter seal weld will be required along with
the lap weld to allow
for air testing. Less frequently, contract documents will
require a full fillet weld both
inside and out. The nominal engagement of a lap-welded joint is
2 to 3 in. (50 to
75 mm) deep with a minimum required final overlap between the
bell and the spigot
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INSTALLATION OF STEEL WATER PIPE4 IN. (100 MM) AND LARGER 21
of 1 in. (25 mm) or 3 times the thickness of the belled pipe,
whichever is greater. The
allowable pullout is 1 in. (25 mm), but in all cases the 1 in.
(25 mm) minimum
required overlap must be maintained. No part of any field weld
shall be closer than
1 in. (25 mm) to the nearest point of tangency to a bell radius.
The allowable angle
of deflection is provided in AWWA Manual M11.
3.4.9.2 Welded butt joint. Welded butt joints are sometimes
specified for
special design conditions. Butt joints are usually
single-V-groove ends and include a
backup ring. The backup ring will be located on the pipe
interior for smaller
diameter pipe and on the exterior or interior for larger pipe
(over 36 in. [900 mm] in
diameter). Field joints shall be assembled so that seams in
adjacent pipes are offset
from each other by at least five times the thickness of the
thicker of the pipes being
joined. Single-V-groove butt joints may be welded from the
outside of the pipe, or
from the inside of the pipe if the diameter is large enough. The
backing rings may be
left in place after welding. Line-up clamps can assist in the
pipe installation. The
installation procedure of field-welded butt joints is basically
identical to the above
except that when the two ends have touched, caution should be
exercised to ensure
that the proper root opening is achieved and the pipe is firmly
secured in position
prior to installing subsequent pipe segments.
3.4.9.3 Welded butt-strap joints. Where welded butt-strap joints
are used,
the butt straps shall have a minimum plate thickness equal to
the thinnest member
being joined and shall be fabricated from material having
equivalent chemical and
physical properties. In accordance with the ANSI/AWWA C206, the
strap shall have
a minimum width of 4 in. (100 mm) or the width necessary to
obtain a minimum
lap between pipe ends and the butt strap.
For butt-strap joints, the seams of adjacent pipe sections may
be in alignment
provided that the butt-strap seams are offset from the pipe
seams by at least five times
the thickness of the thicker member involved in the joint. The
butt strap may be
welded on the pipe exterior, interior, or both.
3.4.9.4 Welded joint testing. Joint testing is generally
performed by air
testing of double fillet welds, magnetic particle or dye
penetrant testing of single fillet
welds, and magnetic particle testing of butt-welded joints.
Limited use of vacuum
look box testing has been utilized as an alternate method for
fillet welds and butt
welds. Limited use of radiographic testing and ultrasonic
testing has been utilized as
alternate methods of testing butt joints. Radiographic testing
is not recommended for
use on the joint types covered in this standard. The test method
shall be specified in
Copyright 2007 American Water Works Association. All Rights
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22 AWWA C604-06
the contract documents. These test methods and repair of
defective welds are further
described in ANSI/AWWA C206.
3.4.10 Pipe cutting. Prior to cutting, pipe shall be checked to
ensure it is
within the necessary tolerance for proper assembly with the
adjoining pipe. If the
adjoining pipes are not within the needed longitudinal
tolerance, either replace the
segment or use an alternate field joint such as a butt strap.
Cutting pipe for insertion
of valves, fittings, or closure pieces shall be done in
conformance with all safety
requirements. Cutting may be performed by abrasive saw,
oxygen-acetylene torch,
plasma arc, air-arc, or other suitable means. The resulting cut
end will require
corrective preparation prior to assembly with the adjoining
pipe. Cut ends and rough
edges shall be ground smooth.
3.4.11 Expansion joints. Provisions shall be made for the
expansion and
contraction of exposed lines. Where individual pipe lengths are
anchored and sleeve-
type couplings are used for field joints, the joints must allow
enough movement so
that expansion and contraction is not cumulative over an
excessive length. Thermal
expansion is usually accommodated for trench-laid welded
pipelines to avoid the
accumulation of expansion and contraction during installation.
These joints usually
include a lengthened bell which is welded only after all
adjacent pipe has been welded
and buried.
3.4.12 Bonding of joints. When required by the contract
documents, the
bonding of nonwelded joints shall be utilized to make the line
electrically continuous
to allow for monitoring of possible corrosion along the
pipeline. Bonding jumpers
(or optional s or z bars) will have to be welded in the field,
joining the spigot and
the bell. The weld should be kept close to the ends of the pipe
to allow joint end
coatings to cover the bonding jumpers.
3.4.13 Protective coatings at field joints. Generally, pipe
lengths are coated
and lined, excluding only the pipe ends that are completed in
the field. After field
assembly, the exterior and interior joint ends shall be
completed with coatings that
are compatible with the original coating system of the pipe and
in conformance with
the applicable AWWA standards. The type of pipe coating and end
coating shall be
determined by the contract documents. Various pipe end coatings
and linings are
available, which are further described in ANSI/AWWA C203,
ANSI/AWWA C205,
ANSI/AWWA C209, ANSI/AWWA C210, ANSI/AWWA C216, ANSI/
AWWA C217, and ANSI/AWWA C222. For application and repair of
these
materials, follow the appropriate AWWA standard and the
manufacturers recom-
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INSTALLATION OF STEEL WATER PIPE4 IN. (100 MM) AND LARGER 23
mendations. Three commonly used materials for pipe end field
coatings are heat-
shrink sleeves (ANSI/AWWA C216), tape coating (ANSI/AWWA C209),
and mortar
coating (ANSI/AWWA C205). Field joint and repair applications
for these two
materials are briefly described by this standard.
3.4.13.1 Tape wrapping field joints. Generally, pipe lengths are
coated,
excluding only the pipe ends that are completed in the field.
The tape is provided in
various widths for various needs, but is generally 6 to12 in.
(150 to 300 mm) wide.
Taping can be completed at any temperature as long as the roll
body temperature
of the tape is maintained above 70F (21C). The procedure for
proper tape
wrapping of field joints is fully described in AWWA C209 and is
summarized as
follows:
1. Make sure the joint to be taped is complete, the gasket is
checked, the
weld is inspected and the metal is cool to a temperature below
130F (54C).
2. Clean the area to be taped with a rag to make sure all
moisture has been
removed.
3. Prime all around the joint, including several inches on both
sides beyond
the area where the actual joint tape will be applied. Place
filler material at all pipe
joints and at irregularities to create a smooth surface. (Lap
welds, where the exterior
is a full thickness weld, and butt welds do not require filler
material.)
4. Start in a downhill direction of the pipe and wrap two
complete layers
around the pipe until overlapping the starting point by a
minimum of 4 in. (100
mm). Cut the tape so as not to damage the field coating. The
start and stop spots do
not need to be much farther than 10 to 15 from off the top
centerline.
5. Make sure the tape around the joint is wrinkle-free and
stretched taut. It
is preferable to keep the welded bonding jumper close to the
pipe ends and wrap the
whole area with the tape as the joint is wrapped.
6. Make sure that partial rolls of tape go around at least one
complete wrap.
7. Inspect the completed wrap using a holiday detector.
3.4.13.2 Taped pipe repairs. Many taped pipelines include a
3-layer system.
The first layer that actually bonds to the pipe is typically a
black tape. The second
layer is a higher-density tape to give durable protection during
handling. The third
layer is a tape that provides good protection to the inner
layers of tape. In most cases
this outer layer is white. The three layers are generally
supplied in three different
colors so that in the event of damage, the colors will assist in
determining the extent
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24 AWWA C604-06
of damage to the total tape system. The procedure for properly
taped pipe repairs is
fully described in ANSI/AWWA C209 and is summarized as
follows:
1. Minor wrinkles, scuffs, or any tears located on the edge of
the tape that
do not go past the overlap area are generally acceptable. These
conditions listed still
give the tape a full film thickness, and it is not practical to
remove the high-density
machine-applied tape and replace it with a softer patch-type
material.
2. If a tear occurs in only the outer layer, repair the damaged
area with one
layer of tape with a minimum overlap of 4 in. (100 mm) onto the
existing coating
system.
3. If the damaged coating area shows evidence of going further
into the
coating system, use the repair method outlined below.
a. Cut away the damaged tape at an angle tangent to the surface
of the pipe
so that the tape system is not cut or damaged any further.
b. Wipe clean the area to be taped and make sure it is dry and
free from dirt.
c. Prime the area to be repaired and let the primer dry to a
tackiness before
applying the repair tape.
d. Cut the tape to such a size that it extends beyond the
damaged area for a
minimum of 4 in. (100 mm) in all directions around the area to
be repaired. Apply
the tape starting at the center and working toward the edge,
making sure to smooth
out all wrinkles. Make sure the primed area extends past the
tape edges.
e. Only one layer of repair tape is required on damages that
affect the outer
layer of tape. If a second layer of tape is required to complete
the patch, place the
second layer of patch material over the first with a minimum of
1 in. (25 mm)
overlap in all directions of the bottom patch. It will always
require two pieces of tape
to accomplish this overlap process.
f. Perform a holiday test on the repair area.
3.4.13.3 Heat-shrink sleeves on field joints. Heat-shrink
sleeves are used to
protect field joints from moisture and oxidation. The procedure
for proper
application of heat-shrink sleeves is fully described in
ANSI/AWWA C216 and is
summarized as follows:
1. Clean the area of the heat-shrink sleeve to remove all
moisture, soil, and
foreign materials. Place filler material at all pipe joints and
at irregularities to create a
smooth surface. (Lap welds, where the exterior is a full
thickness weld, and butt welds
do not require filler material.)
2. Preheat the area according to the manufacturers
requirements.
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INSTALLATION OF STEEL WATER PIPE4 IN. (100 MM) AND LARGER 25
3. Fit the sleeve around the joint.
4. Heat the sleeve to shrink and seal the sleeve to the
joint.
5. Using rollers, remove all wrinkles to ensure that the sleeve
has intimate
contact to the pipe.
3.4.13.4 Cement mortar for field joints and repairs. Pipe
manufacturers
generally coat and line the pipe lengths, excluding only the
pipe ends that are
completed in the field. The pipe ends and areas needing repairs
shall be clean of
deleterious materials and the surface prepared for the cement
mortar in accordance
with ANSI/AWWA C205. When feasible, interior cement mortar for
field joints and
repairs shall be applied after the trench has been backfilled.
Cement mortar shall be
poured in the exterior joint space through a grout band that is
wrapped around the
joint and firmly strapped onto both sides after field joint
assembly. Repairs to the
exterior mortar coating of the pipe shall be made during pipe
installation and before
backfilling. Cracks in cementmortar-lined steel pipe are a
common occurrence.
These cracks are most commonly shrinkage cracks, which are
caused when the
mortar dries out. Contributing factors may be unprotected pipe
ends, rough
handling, or thermal stresses caused by weather. It is important
to keep the pipe ends
capped and small amounts of water added to the inside in hot,
dry climates. Cracks
of 1/16 in. (1.6 mm) or less are acceptable by ANSI/AWWA C205.
If cracks exceed1/16 in. (1.6 mm), a slurry mixture can be made and
brushed over the cracked area
prior to filling the pipeline. The material requirements and
application procedures of
cement- mortar for field joints and general repairs are
described in ANSI/AWWA
C205. Do not fill pipe for 72 hr after the last concrete
repair.
Sec. 3.5 Fitting Installation
3.5.1 Examination of material. Prior to installation, valves
shall be inspected
for direction of opening, number of turns to open, freedom of
operation, tightness of
pressure-containing bolting and test plugs, cleanliness of valve
ports and especially
seating surfaces, handling damage, and cracks. Defective valves
shall be marked and
held for final disposition as required by the contract
documents. All bolts and nuts,
with the exception of seat-adjusting bolts or screws in
butterfly valves, shall be
checked for specified tightness. Seat-adjusting bolts in
butterfly valves shall only be
adjusted when recommended by the manufacturer.
3.5.2 Placement. Valves, fittings, plugs, and caps shall be set
and joined to
the pipe in the manner specified in Sec. 3.3 for cleaning and
laying and Sec. 3.4 for
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26 AWWA C604-06
joining pipe, except that 12-in. (300-mm) and larger valves
shall be provided with
special support, such as treated timbers, crushed stone,
concrete pads, or a sufficiently
tamped trench bottom, so that the pipe will not be required to
support the weight of
the valve. Valves installed aboveground or in plant piping
systems shall be supported
to prevent bending of the valve end connections as a result of
pipe loading. Valves
shall be installed in the closed position; however, valves
should be reopened after
installation to provide access, allow ventilation, and ensure
proper operation.
3.5.2.1 In no case shall valves be used to bring misaligned pipe
into alignment
during installation. Pipe shall be supported in such a manner as
to prevent stress on
the valve.
3.5.2.2 Thrust resulting from closure of valves shall be
carefully considered
during testing of the piping system and vaults.
3.5.2.3 Mains shall be drained through drainage branches or
blowoffs.
Drainage branches, blowoffs, and appurtenances shall be provided
with control valves
and shall be located and installed as shown on the contract
documents. Discharges
shall be directed away from the pipe alignment, in order not to
affect the trench
stability, and shall be in accordance with federal, state, and
local point discharge
requirements.
3.5.2.4 Air release and vacuum vents shall be installed in
accordance with the
contract documents at the high points in the line and in areas
of potential negative
pressure. The location, number, and size of these air release
and vacuum vents should
be provided in the contract documents. The air release and
vacuum vents shall be
protected in locations where freezing temperatures are
encountered.
3.5.3 Valve vaults. Valve vaults are designed to prevent any
settlement that
may damage the valve and prevent its proper operation.
Installation of the pipe and
valve in the vault shall be such that the operating nut shall be
readily accessible for
operation through the opening in the valve vault, which shall be
set flush with the
surface of the finished pavement or such other level as may be
specified.
Valves and fittings shall be coated with a compatible coating
according to the
coating manufacturers recommendations and the applicable AWWA
standard.
Additional information regarding installation of gate valves can
be found in the
appendixes of ANSI/AWWA C500 and ANSI/AWWA C509.
3.5.4 Plugs and caps. Before putting the installed pipe and
appurtenances
under test pressure, consider all dead ends and the methods
available to restrain the
dead ends, blowoff valves, and so on, against the force
generated by the test pressure.
Copyright 2007 American Water Works Association. All Rights
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INSTALLATION OF STEEL WATER PIPE4 IN. (100 MM) AND LARGER 27
Sec. 3.6 Thrust Restraint
The need for thrust restraint is a design consideration that is
not covered by this
standard. Such restraint is commonly provided by welded joints,
thrust collars,
mechanical harnesses, or concrete thrust blocks. Installation of
mechanical joints,
mechanical harnesses, fittings, and welded joints are described
in Sec. 3.3 and
Sec. 3.4. Such restraint is commonly used when pipe pressure
class can cause
excessive movement, when miter joints exceed 5, within vaults,
and when the
known restraint mechanism, such as soil, is not adequate to
ensure pipeline integrity
under operational and transient pressure loads. For design of
thrust restraint, see
AWWA Manual M11.
NOTE: Restraining mechanisms shall be prepared and coated with a
compatible
coating according to the coating manufacturers recommendations
and the applicable
AWWA standard.
Sec. 3.7 Backfilling
The excavated pipe trench will usually also have to accommodate
a specified
thickness of select graded foundation bedding material (see
Figure 5). The
foundation bedding material shall be evenly spread in the bottom
of the trench to
support the pipe along its entire length with the exception of a
few feet near the joint
areas. Backfill shall be accomplished in accordance with the
specified laying
conditions described in Sec. 3.3. Backfilling operations shall
be maintained to avoid
having an excessive amount of exposed installed pipe.
3.7.1 Pipe zone backfill and foundation material. All pipe zone
backfill and
foundation material shall be free from cinders, ashes, refuse,
vegetable or organic
material, boulders, rocks or stones 3 in. (150 mm) in diameter
and larger, frozen soil,
or other unsuitable materials described by the contract
documents.
3.7.1.1 From 12 in. (300 mm) above the top of the pipe to grade,
material
containing stones up to 8 in. (200 mm) in their greatest
dimension may be used
unless otherwise specified.
3.7.1.2 When the type of backfill material is not indicated or
is not specified,
the excavated material may be used provided that such material
consists of loam, clay,
sand, gravel, or other suitable materials.
3.7.1.3 Pipe zone backfill shall be densified around the pipe in
accordance
with Figure 5. The maximum dry density of cohesive soil shall be
between 85 and
95 percent based on ASTM D698 or AASHTO T99 unless otherwise
specified (see
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28 AWWA C604-06
Figure 5). For free-draining soils, the relative density shall
be at least 70 percent as
determined by ASTM D4253 and ASTM D4254 unless otherwise
specified.
Regardless of the method of densification used, materials shall
be brought up at
substantially the same rate on both sides of the pipe. When
installing pipe 36 in.
(900 mm) and larger, use a probe rod method to confirm that the
backfill is properly
consolidated within the pipe lower quadrant (between the pipe
spring line and invert
elevation). Take care to ensure that the pipe is not floated or
displaced before
backfilling is complete.
3.7.1.4 Cohesive soils shall be compacted with mechanical
equipment or hand
tamping. Care shall be taken not to damage coatings during
compaction. Proper
equipment and care in placement will ensure the required
compaction under the
lower quadrant of the pipe. Pipe zone backfill for pipe up to 48
in. (1,200 mm) in
diameter shall be placed in layers of not more than 6 in. (150
mm) in thickness or
25 percent of the pipe diameter, whichever is greater. Pipe zone
backfill for pipe
larger than 48 in. (1,200 mm) in diameter shall be placed in
layers not exceeding
24 in. (600 mm) in thickness and subject to meeting the
compaction requirements.
3.7.1.5 Free-draining soils may be densified by tamping with
water-using
devices, or through methods such as water jets, immersion-type
vibrators, or
flooding. These soils are usually placed in a minimum of two
layers, with the first
layer placed loose to the spring line of the pipe. The thickness
of the layers shall not
exceed the penetrating depth of the vibrators if consolidation
is performed by jetting
and internal vibration.
3.7.1.6 Pipe zone bedding and backfill may be class C1, C2, or
C3 (95, 90,
or 85 percent dry density or 70 percent relative density as
expressed in Sec. 3.7.1.3)
or as specified in the contract documents. Pipe zone backfill
shall be densified around
the pipe to the specified height over the top of the pipe.
Regardless of the method of
densification used, backfill material shall be brought up at
substantially the same rate
on both sides of the pipe. Care shall be taken not to float or
displace the pipe before
backfilling is complete.
Trench backfill above the pipe zone shall not be placed until
the compaction of
the pipe zone backfill and foundation are satisfactorily
complete. To prevent damage
to the pipe, sufficient compacted backfill shall be placed over
the pipe before allowing
any type of vehicle over it.
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INSTALLATION OF STEEL WATER PIPE4 IN. (100 MM) AND LARGER 29
NOTE: Loosely placed backfill above the pipe may promote
unwanted
settlement, which could be detrimental to improvements
subsequently placed over
the trench.
3.7.1.7 When required, the pipe is delivered with internal
bracing. The
vertical bracing limits the maximum vertical deflection of the
pipe during installation
and backfilling operations and shall not be removed until
backfilling is complete,
unless it can be demonstrated that the pipe roundness tolerance
will not be adversely
affected and the pipe roundness can be verified after
backfilling.
3.7.1.8 If excavated material is indicated or specified for
backfill, and there is
a deficiency due to a rejection of a part thereof, the required
amount of sand, gravel,
or other approved material shall be provided.
3.7.1.9 Maximum aggregate size for purposes of definition is as
follows: (a)
sand is material graded from fine to coarse, containing not less
than 95 percent
Figure 5 Pipe bedding
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30 AWWA C604-06
passing a No. 4 sieve (4.75 mm) and not more than 5 percent
passing a No. 200 sieve
(0.75 mm); (b) gravel is a reasonably uniform combination,
containing no boulders
or stones larger than 3 in. (75 mm) and not containing excessive
amounts of clay and
loam; (c) crushed rock is material with 100 percent passing a
3/4-in. (19 mm) sieve
and no more than 25 percent passing a No. 100 sieve.
The maximum backfill aggregate size for cementmortar coated pipe
shall be 3-in.
(75 mm) minus. The maximum aggregate size for flexible coated
pipe shall be 3/4-in.
(19 mm) minus.
3.7.2 Compaction. When special backfill compaction procedures
are
required, they shall be accomplished in accordance with contract
documents or
applicable federal, state or provincial, and local
regulations.
3.7.3 Partial backfilling during testing. Newly installed
pipelines are nor-
mally tested after backfilling. When unusual conditions require
that pressure and
leakage testing be accomplished before completion of
backfilling, or with pipe joints
accessible for examination, sufficient backfill material shall
be placed over the pipe
barrel between the joints to prevent movement, and due
consideration shall be given
to restraining thrust forces during testing. In particular,
restrained-joint systems,
which derive their stability from the interaction of the pipe
and soil, shall be
backfilled as necessary prior to testing.
Sec. 3.8 Flushing
Foreign material left in pipelines during installation can
result in valve or
hydrant seat leakage during pressure tests. Every effort shall
be made to keep lines
clean during installation. Thorough flushing is recommended
prior to a pressure test;
flushing shall be accomplished by partially opening and closing
valves several times
under expected line pressure, with flow velocities adequate to
flush foreign material
out of the valves.
NOTE: Discharge shall be directed aw