ASTM F690-86(2003)e1

Standard Practice for Underground Installation of Thermoplastic Pressure Piping Irrigation Systems

SCOPE
1.1 This practice covers general and basic procedures related to the proper installation of thermoplastic, flexible, pressure piping, 36 in. nominal size and smaller, for underground irrigation systems. Because there is considerable variability in end-use requirements, soil conditions, and thermoplastic piping characteristics, it is the intent of this practice to outline general objectives and basics of proper installation and to provide pertinent references, rather than to prescribe detailed installation procedures.  
1.2 This practice should not be used for installing thermoplastic underground sewer, drain, potable water, conduit or gas service piping.  
1.3 The values stated in inch-pound units are to be regarded as the standard. Values in parentheses are given for information only.  
1.4 This standard does not purport to address all of the safety problems, 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: 09-Aug-2003
• Technical Committee: F17 - Plastic Piping Systems
• Drafting Committee: F17.61 - Water

Relations

• Replaces: ASTM F690-86(2003) - Standard Practice for Underground Installation of Thermoplastic Pressure Piping Irrigation Systems
• Effective Date: 10-Aug-2003
• Replaced By: ASTM F690-86(2003)e2 - Standard Practice for Underground Installation of Thermoplastic Pressure Piping Irrigation Systems (Withdrawn 2012)
• Effective Date: 10-Aug-2003
• Referred By: ASTM F1668-16(2022) - Standard Guide for Construction Procedures for Buried Plastic Pipe
• Effective Date: 10-Aug-2003

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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
An American National Standard
e1
Designation:F 690–86(Reapproved2003)
Standard Practice for
Underground Installation of Thermoplastic Pressure Piping
Irrigation Systems
This standard is issued under the fixed designation F 690; 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 (e) indicates an editorial change since the last revision or reapproval.
e NOTE—Keywords editorially added in November 2003.
1. Scope internal restriction or obstruction, which could reduce line
capacity below design requirements.
1.1 This practice covers general and basic procedures re-
3.2 All joining materials shall be of composition that will
lated to the proper installation of thermoplastic, flexible,
not damage the pipe and shall be recommended for use at the
pressure piping, 36 in. nominal size and smaller, for under-
design pressure for the pipeline. Consult the manufacturer for
ground irrigation systems. Because there is considerable vari-
design and installation recommendations and refer to Practice
ability in end-use requirements, soil conditions, and thermo-
F 402.
plastic piping characteristics, it is the intent of this practice to
3.3 Whensteelorothermetallicjoiningmaterials,subjectto
outline general objectives and basics of proper installation and
corrosion, are used in the line, they shall be adequately
toprovidepertinentreferences,ratherthantoprescribedetailed
protected by wrapping or coating with high quality corrosion
installation procedures.
preventatives. Wrapping or coatings that are applied on metal-
1.2 This practice should not be used for installing thermo-
lic surfaces should not be applied on plastic pipes and fittings
plasticundergroundsewer,drain,potablewater,conduit,orgas
unless it is first established by consulting the piping manufac-
service piping.
turer that they have no detrimental effect on the plastic.
1.3 The values stated in inch-pound units are to be regarded
3.4 Joining specifications are listed under 2.1.3.
asthestandard.Valuesinparenthesesaregivenforinformation
3.5 Manufacturers of joining materials should be consulted
only.
for specific assembly instructions not covered by existing
1.4 This standard does not purport to address all of the
specifications. When requesting information, the intended ser-
safety problems, if any, associated with its use. It is the
vice application should be defined.
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica-
4. Trench Preparation
bility of regulatory limitations prior to use.
4.1 Trench Depth—Instablegranularsoils,whichtendtobe
2. Referenced Documents relatively smooth and free of all rocks and debris larger than ⁄2
in. (13 mm) in sizes, excavation may proceed directly to final
2.1 ASTM Standards:
grade.Where rocks of other protrusions are encountered which
D 2487 Test Method for Classification of Soils for Engi-
may cause point loading on the pipe, the trench bottom should
neering Purposes (Unified Soil Classification System)
be overexcavated to permit installation of proper bedding (see
D 2488 Practice for Description and Identification of Soils
Section 5).
(Visual-Manual Procedure)
4.2 Trench Width—The width of the trench at any point
F 402 Practice for Safe Handling of Solvent Cements,
below the top of the pipe should be established with attention
Primers,andCleanersUsedforJoiningThermoplasticPipe
given to these considerations:
and Fittings
4.2.1 The wider the trench at the top of the pipe, the greater
3. Joints and Connections
theearthloadimposedonthepipeuntiltheprismloadhasbeen
achieved.
3.1 Joints and connections shall be assembled to withstand
4.2.2 Trench width should allow sufficient and safe working
the design working pressure for the pipeline without leakage,
room for proper alignment and assembly of the joints. Gener-
ally,atrenchwidthatthetopofthepipeofabout2ft(600mm)
This practice is under the jurisdiction of ASTM Committee F17 on Plastic
wider than the pipe diameter is adequate. However, for pipe
Piping Systems and is the direct responsibility of Subcommittee F17.61 on Water.
with an 18-in. (457-mm) diameter and larger in a vertical-
Current edition approved Aug. 10, 2003. Published September 2003. Originally
walled trench, a clearance of 3 ft (1 m) wider than the nominal
approved in 1980. Last previous edition approved in 1994 as F 690 – 84 (1994).
Annual Book of ASTM Standards, Vol 04.08. pipesizemaybeneeded.Forslopedtrenches,aminimumofan
Annual Book of ASTM Standards, Vol 08.04.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
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F 690–86 (2003)
18-in. (457-mm) greater trench bottom width than the pipe 5.2 If the pipe is to be assembled above ground, it should be
diameter allows sufficient width. If a wider trench becomes lowered into the trench, taking care not to drop it or damage it
necessary, the enlargement should be restricted as much as against the trench walls, nor to subject it or its joints to
possible to only that section above the top of the pipe. treatment, such as, dragging or excessive bending which could
4.2.3 Trench width should allow adequate room for snaking be injurious to the piping. With elastomeric seal joints, take
when recommended by the manufacturer or as may be required care to avoid joint displacement and pull out.Allow heat-fused
to accommodate thermal expansion or contraction. joints to cool or solvent-cemented joints to cure for the
4.2.4 Narrower trench widths may be utilized by joining the minimum prescribed time before moving the pipe. While
pipe above ground and lowering it into the trench, provided moving larger diameter pipe lines, care should be taken to
enough room is available in the trench for proper haunching. avoid excessive stressing of the joints.
Precautions outlined in 5.2 shall be followed.
5.3 Ensure that elastomeric seal joints are not installed so
4.3 Trench Depth—The trench depth shall be established they remain excessively deflected. Consult the pipe manufac-
with consideration given to requirements imposed by founda-
turer for maximum permissible joint deflection limits.
tion, bedding, pipe size, and cover.
5.4 Changes in the grade and line of direction of the pipe
4.4 Foundation—An adequate and stable foundation should
shallbelimitedandshallbegradualenoughsothatthebending
be present, or provided, for proper support at the total trench
of the pipe will develop neither excessive diametrical expan-
load.
sion nor excessive bending stresses.At no time should the pipe
4.4.1 Foundation preparation is not necessary when smooth
be blocked or braced to hold a bend. Excess curvature can
stable trench bottoms are encountered.
create stresses which could induce pipe failure under pressure.
4.4.2 Foundation preparation is necessary when unstable
Consult the pipe manufacturer for recommended minimum
trench bottom conditions are encountered.The designer should
pipe bending radius.
specify the stabilizing method and materials which will satis-
5.5 When installing pipe with elastomeric seal, flanged
factorily stabilize the encountered condition and provide ad-
joints, or with any connector which protrudes beyond the pipe
equate and permanent support.
diameter, bell holes should be excavated in the bedding
4.5 Bedding—The bedding material should consist of
material or trench bottom to permit the pipe to be continuously
gravel, sand, silty sand, silty gravel, or clayey sand in granular
supported. After pipe assembly and placement in the trench,
form and having a maximum particle size of ⁄4 in. (19 mm).
each bell hole should be filled with bedding material and
4.5.1 Bedding shall be provided whenever rock, hard pan,
compactedifnecessarytoattainthesamegeneraldensityasthe
boulders, or other materials that might damage the pipe are
rest of the bedding.
encountered in the trench bottom at the established pipe grade.
5.6 It is advisable to permit newly installed pipe to cool to
4.5.2 When bedding is used, it shall be kept as nearly
approximately ground temperature prior to backfilling. This
uniform in depth as possible to minimize differential settle-
will minimize the development of contraction stresses on the
ment.
joints and, in the case of solvent-cemented connections, it will
4.6 Minimum Earth Cover—Protection from traffic loading
prevent the possibility of joint separation due to contraction
or frost penetration, or both should be considered when
forces acting on an incompletely cured bond. Typically, pipe
establishing minimum earth cover requirements.
willcooladequatelysoonafterbeingplacedonashaded-trench
4.6.1 For installations exposed to normal farm vehicle
bottom.
traffic, the minimum total cover should not be less than:
5.7 Where differential settlement could create concentrated
Pipe1to2 ⁄2 in. in diameter: 18 in. (450 mm)
loading on a pipe or joint, for example, at a point of connection
Pipe 3 to 4 in. in diameter: 24 in. (600 mm)
of a buried pipe to a rigid structure, such as a manhole,
Pipe 5 in. and larger in diameter: 30 in. (750 mm)
Pipe 5 to 18 in. in diameter: 30 in. (750 mm) manufacturer’s recommendations should be followed to pre-
Pipe 18 in. and larger in diameter: 36 in. (900 mm)
vent, or to properly relieve, damaging andshearingforces. One
technique is to use extra care when compacting the foundation
4.6.2 The pipe line should be installed at sufficient depths to
and bedding under a rigid structure. Other techniques might
provide protection from traffic crossing, farming operations,
include construction of a supporting structure underneath the
and soil cracking. Load-bearing capabilities of installed pipe
joint and the pipe of about three diameters in cross section or
vary with type of pipe, type of backfill, soil conditions, and
the utilization of a flexible joint.
installation procedures. Consult the manufacturer for informa-
5.8 Special Installation—With certain pipes and in some
tion on product response to expected maximum earth loading.
soil conditions it is possible to install long lengths of pipe by
4.6.3 The trench depth shall be sufficient to ensure place-
the plowing-in technique. Consult the manufacturer for recom-
ment of the top of the pipe at least 10 in. (250 mm) below the
mendations.
known frost line. When conditions and design requirements
prevent satisfaction of this requirement, system design and
installation must ensure proper drainage in the low portions of 6. Thrust Blocking
the line.
6.1 When installing piping systems that include joints that
are not self restraining (for example, elastomeric seal type)
5. Pipe Assembly and Installation
thrust blocking may be necessary at certain points in the
5.1 Preparation of Joints—Joint assembly shall be done in system, such as changes in direction, in order to prevent
accordance with specifications listed under 2.1.3. possible disengagement of the fitting from the pipe.
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F 690–86 (2003)
6.2 Thrust blocking is required where line shift or joint 7.2.1 Before filling and proceeding to test, sufficient time
separation at system operating pressure can be anticipated, that should be allowed for solvent-cemented joints to cure or
is, pump discharge, directional changes, reducers, and dead heat-fused joints to cool.
ends. Thrust blocking is essential to the proper performance of 7.2.2 Withvalvesatendsandhighpointsopen,thepipelines
high pressure irrigation piping when the system includes should be slowly filled with water, limiting the flow velocity to
non-self-restraining joints. (See Fig. 1.) 1 ft/s (0.3 m/s) to prevent surge, or water hammer, and air
6.3 Thrust Block Construction: entrapment.
6.3.1 The thrust block should be constructed of concrete 7.2.3 Ensure that all entrapped air is released from the line
having a compression strength of 2000 psi (14 MPa) or more. while filling. The system should include appropriate air and
Wood blocking, or stone blocking with wood wedges, are not vacuum relief valves for proper function during operation after
acceptable. installation.
6.3.2 The thrust block acts as an anchor between pipe or 7.2.4 The pipeline should be filled but not pressurized until
fitting and the solid trench wall. The size of the thrust block the engineer is ready to witness or conduct the pressure test.
should be adequate to prevent pipe movement at the point of 7.3 Inspection and Repairs—The line should be pressurized
thrust. Consult the system designer. to 125 % of the system’s design operating pressure, for the
6.3.3 The thrust block cavity should be hand dug into time necessary to check all joints but not to exceed 1 h. While
undisturbed soil and framed with soil or wood to hold freshly under pressure, inspect all joints for leaks. Any leaks found
poured concrete. The earth-bearing surfaces should be undis- should be repaired, and the line recharged and retested.
turbed.
8. Backfilling Procedures
6.3.4 Before pressurizing the line, ensure that adequate time
is allowed for the concrete thrust blocks to set.
8.1 Haunching and Initial Backfill—This practice covers
those thermoplastic piping products which may be deflected
7. Line Charging and Testing
considerably, without structural damage. The flexibility of the
7.1 If possible, the pipeline should be thoroughly inspected pipe enables it to utilize the passive resistance of the soil to
and tested for leaks before backfilling. When so testing, it is support loads externally applied to the pipe. The resistance of
advisable to anchor the pipe by placing haunching and initial the soil is affected by the type of soil, its density and moisture
backfill up to about 6 in. (150 mm) over the pipe, taking care content. Therefore, the higher the soil resistance, the less the
to leave all joints and fittings exposed for inspection. pipe will deflect. Proper techniques for pipe embedment are
7.2 Line Charging: necessary to ensure that the passive soil resistance required to
FIG. 1 Types of Thrust Blocking
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F 690–86 (2003)
prevent excessive pipe deflection will be developed and 8.2 Compaction Methods:
maintained.Thedesignerwilldeterminetheminimummaterial
8.2.1 When using mechanical tamping to achieve desired
requirements and extent of compaction depending on pipe
backfill soil densities, care must be taken to ensure that the
selected and the end-use conditions.The following embedment
tamping or vibratory equipment does not come in contact with
materials are recommended (see Classification D 2487 and
the pipe. Care should be taken to avoid defo
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