ASTM C1173-22

Standard Specification for Flexible Transition Couplings for Underground Piping Systems

ABSTRACT
This specification describes the properties of devices or assemblies suitable for use as flexible transition couplings for underground drainage and sewer piping systems. Couplings that may include bushings or inserts, and meet the requirements of this specification are suitable for joining plain end pipe or fittings. Couplings shall be permitted to have a center stop, the components shall be designed so that the elastomeric material is compressed to form a hydrostatic seal when the joint is assembled. Assemblies shall be tested in different areas and each component shall conform to specified physical and mechanical requirements, namely: hardness, tensile strength, elongation, heat aging, hardness, ozone resistance, water absorption, and chemical resistance for the elastomeric materials; tension band performance, torque resistance, free running torque for the stainless steel materials; and deflection sealing resistance, and shear loading resistance for the joint assemblies.
SCOPE
1.1 This specification describes the properties of devices or assemblies suitable for use as flexible transition couplings, hereinafter referred to as “couplings,” for underground drainage and sewer piping systems.  
1.2 Flexible transition couplings that conform to the requirements of this standard are suitable for joining plain-end pipe or fittings. The pipe to be joined shall be of similar or dissimilar materials, size, or both.  
1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.  
1.4 The ASTM standards referenced herein shall be considered mandatory.  
1.5 The committee with jurisdiction over this standard is not aware of another comparable standard for materials covered in this standard.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-May-2022
• ICS: 23.040.60 - Flanges, couplings and joints
• Technical Committee: A04 - Iron Castings
• Drafting Committee: A04.75 - Gaskets and Coupling for Plumbing and Sewer Piping

Relations

• Refers: ASTM A240/A240M-23a - Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
• Effective Date: 01-Nov-2023
• Refers: ASTM A493-23 - Standard Specification for Stainless Steel Wire and Wire Rods for Cold Heading and Cold Forging
• Effective Date: 01-Nov-2023
• Refers: ASTM D3045-18 - Standard Practice for Heat Aging of Plastics Without Load
• Effective Date: 01-Aug-2018
• Refers: ASTM A644-17 - Standard Terminology Relating to Iron Castings
• Effective Date: 01-Nov-2017
• Refers: ASTM A240/A240M-17 - Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
• Effective Date: 01-Nov-2017
• Refers: ASTM A240/A240M-16a - Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
• Effective Date: 01-Dec-2016
• Refers: ASTM A240/A240M-16 - Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
• Effective Date: 01-May-2016
• Refers: ASTM A493-16 - Standard Specification for Stainless Steel Wire and Wire Rods for Cold Heading and Cold Forging
• Effective Date: 01-Mar-2016
• Refers: ASTM A240/A240M-15b - Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
• Effective Date: 01-Nov-2015
• Refers: ASTM A240/A240M-15a - Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
• Effective Date: 01-Mar-2015
• Refers: ASTM A240/A240M-15 - Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
• Effective Date: 01-Jan-2015
• Refers: ASTM A644-14 - Standard Terminology Relating to Iron Castings
• Effective Date: 01-Oct-2014
• Refers: ASTM A240/A240M-14 - Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
• Effective Date: 01-May-2014
• Refers: ASTM A240/A240M-13c - Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
• Effective Date: 01-Nov-2013
• Refers: ASTM A493-09(2013) - Standard Specification for Stainless Steel Wire and Wire Rods for Cold Heading and Cold Forging
• Effective Date: 01-Oct-2013

Overview

ASTM C1173-22 is the internationally recognized standard specification for flexible transition couplings for underground piping systems. Developed by ASTM International, this standard outlines the requirements and test methods for devices used to connect plain-end pipe or fittings in underground drainage and sewer applications. The couplings covered under this standard are intended to provide reliable, leakproof connections between pipes of the same or different sizes and materials, making them suitable for a wide variety of trenchless repair, rehabilitation, and new installations of piping infrastructure.

Key Topics

• Scope and Applicability
  ASTM C1173-22 specifies the design, material, and performance requirements for flexible couplings used in underground drainage and sewer piping systems. The standard applies to couplings with or without bushings, inserts, center stops, or shear rings, and allows joining of pipes and fittings of similar or dissimilar materials and sizes.

• Material Requirements

  • Elastomeric components must exhibit specified properties such as hardness, tensile strength, elongation, heat aging, ozone resistance, water absorption, and chemical resistance.
  • Metallic components, including tension bands and tightening mechanisms, must be made of 300 series stainless steel and meet strict torque resistance criteria.

• Types of Couplings

  • Type A: Elastomeric gasket with corrosion-resistant tension bands, optionally with inserts and/or center stops.
  • Type B: Elastomeric gasket with a corrosion-resistant shear ring, tension bands, tightening mechanism; optionally includes inserts and/or center stops.
  • Type C: Elastomeric compression seal couplings.

• Performance Testing
  Couplings must pass rigorous tests including:

  • Deflection sealing resistance under internal hydrostatic pressure
  • Shear loading resistance for Type B couplings
  • Various physical and mechanical properties for all elastomeric and metallic components

• Marking and Certification
  Each coupling must be properly marked with the manufacturer’s identification and information relating to pipe compatibility.

Applications

Flexible transition couplings manufactured in accordance with ASTM C1173-22 are essential for:

• Underground Drainage and Sewer Systems:
  Connecting plain-end pipes, whether made of the same or different materials, across new installations, repairs, or rehabilitation projects.
• Municipal, Industrial, and Residential Infrastructure:
  Frequently used in water treatment plants, stormwater management, and sanitary sewer projects.
• Compatibility Across Pipe Types:
  Suitable for joining pipes made of various materials such as PVC, cast iron, concrete, clay, or steel, enabling versatile use during infrastructure upgrades or emergency repairs.
• Trenchless Rehabilitation:
  Especially valuable in situations where minimal excavation is desired, as flexible couplings can adapt to slight misalignments or movements underground.

Related Standards

For comprehensive installation and material compatibility, ASTM C1173-22 frequently references, or is used in conjunction with, the following standards:

• ASTM A240/A240M - Specification for Stainless Steel Plate, Sheet, and Strip
• ASTM A493 - Specification for Stainless Steel Wire and Wire Rods
• ASTM D412 - Test Methods for Vulcanized Rubber and Thermoplastic Elastomers-Tension
• ASTM D2240 - Test Method for Rubber Property-Durometer Hardness
• ASTM D543 - Practices for Evaluating the Resistance of Plastics to Chemical Reagents

These supporting documents ensure that all materials and methods used in the manufacture and performance evaluation of flexible transition couplings meet internationally recognized quality criteria.

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Keywords: ASTM C1173-22, flexible transition couplings, underground piping systems, drainage couplings, sewer couplings, ASTM standards, pipe connection, elastomeric gaskets, stainless steel clamps, underground drainage standard, municipal piping, trenchless piping rehabilitation.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation:C1173 −22
Standard Specification for
Flexible Transition Couplings for Underground Piping
Systems
This standard is issued under the fixed designation C1173; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope for Cold Heading and Cold Forging
A644Terminology Relating to Iron Castings
1.1 This specification describes the properties of devices or
D395Test Methods for Rubber Property—Compression Set
assemblies suitable for use as flexible transition couplings,
D412TestMethodsforVulcanizedRubberandThermoplas-
hereinafter referred to as “couplings,” for underground drain-
tic Elastomers—Tension
age and sewer piping systems.
D471Test Method for Rubber Property—Effect of Liquids
1.2 Flexible transition couplings that conform to the re-
D543Practices for Evaluating the Resistance of Plastics to
quirements of this standard are suitable for joining plain-end
Chemical Reagents
pipe or fittings. The pipe to be joined shall be of similar or
D573Test Method for Rubber—Deterioration in an Air
dissimilar materials, size, or both.
Oven
1.3 The values stated in inch-pound units are to be regarded D624Test Method for Tear Strength of Conventional Vul-
canized Rubber and Thermoplastic Elastomers
as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only D638Test Method for Tensile Properties of Plastics
D1149Test Methods for Rubber Deterioration—Cracking in
and are not considered standard.
an Ozone Controlled Environment
1.4 TheASTM standards referenced herein shall be consid-
D2240Test Method for Rubber Property—Durometer Hard-
ered mandatory.
ness
1.5 Thecommitteewithjurisdictionoverthisstandardisnot
D3045Practice for Heat Aging of Plastics Without Load
aware of another comparable standard for materials covered in
D6147TestMethodforVulcanizedRubberandThermoplas-
this standard.
tic Elastomer—Determination of Force Decay (Stress
1.6 This international standard was developed in accor- Relaxation) in Compression
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the 3. Terminology
Development of International Standards, Guides and Recom-
3.1 Definitions—For definitions of terms used in this
mendations issued by the World Trade Organization Technical
standard, see Terminology A644.
Barriers to Trade (TBT) Committee.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 center stop, n—an integral part of the gasket centered
2. Referenced Documents
on its axial length, intended to limit the insertion depth of the
2.1 ASTM Standards:
pipe to be coupled.
A240/A240MSpecification for Chromium and Chromium-
3.2.2 clamp assembly, n—that portion of the coupling ex-
Nickel Stainless Steel Plate, Sheet, and Strip for Pressure
cluding the gasket.
Vessels and for General Applications
A493Specification for Stainless Steel Wire and Wire Rods 3.2.3 coupling, n—the complete assembly.
3.2.4 fitting, n—parts of a pipeline other than straight pipe
couplings or valves.
This specification is under the jurisdiction of ASTM Committee A04 on Iron
Castings and is the direct responsibility of Subcommittee A04.75 on Gaskets and 3.2.5 flexible transition couplings, n—devices used to form
Coupling for Plumbing and Sewer Piping.
a leakproof joint between sections of plain-end pipe or fittings
Current edition approved June 1, 2022. Published June 2022. Originally
of the same or different materials, of the same or different size,
approved in 1991. Last previous edition approved in 2018 as C1173–18. DOI:
or any combination of materials or pipe sizes.
10.1520/C1173-22.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
3.2.6 free torque, n—the torque value expressed in
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
lbf·in./Nm when the clamp is tightened four revolutions of the
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. screw nut; while in the free state, this value does not include
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1173−22
TABLE 1 Test Requirements
any breakaway effects due to staking or passage of the band
ends beyond the screw heads. Physical ASTM Test
Properties
Requirements Method
3.2.7 inserts, n—a bushing or ring placed into the coupling
Elastomeric materials
socket to accommodate pipe materials of differing outside
Hardness, nominal shore “A” durometer as 50–75 D2240
diameters. specified by the coupling manufacturer
Hardness, nominal shore “D” durometer as 35–45 D2240
3.2.8 joint, n—the completed assembly of parts consisting
specified by the coupling manufacturer
Tensile strength, min psi (KPa) 1000 (6894) D412,Die C,
of the flexible transition coupling and the joined pipes, or
Fig. 2 or D638
fittings, or both.
Elongation at rupture, min, % 200 D412,Die C,
Fig. 2 or D638
3.2.9 lot, n—a specific quantity of similar material or
Heat aging, 70 h, 158 ± 3.6 °F (70 ± 2 °C) D573 or D3045
collection of similar units from a common source; the quantity
Hardness increase, maximum Durometer 10
offered for inspection and acceptance at any one time. A lot
points
Change in tensile strength, max, % 25
might comprise a shipment, batch, or similar quantity.
Change in elongation, max, % 35
3.2.10 manufacturer, n—the entity that produces the cou-
Ozone resistance no cracks D1149
At 20 % elongation
pling.
For 100 h at 104 ± 3.6 °F (40 ± 2 °C)
3.2.11 plain-end pipe, n—anypipethatdoesnotincludeany
With 50 parts per 100 million
Water absorption, weight gain, %, max 20 D471
bell, hub, threaded area, or other means of joining.
Chemical resistance, 48 h, 74 ± 3.6 °F (23 no weight loss D543
3.2.12 shear ring, n—an interior or exterior element which
± 2 °C)
Compression set, max, % 25 D395 Method B
is used to span the distance between the pipe ends within a
Stress relaxation, min. % force retention 30 D6147
couplingsoastoprovideincreasedresistancetoaxialdisplace-
Tear strength, min, lbf/in. (N/cm) 150 (268.5) D624 Die C
ment.
4. Classification
4.1 The couplings shall be permitted to have a center stop.
6.3 Elastomericgasketsandinsertsofsingle,multi-piece,or
The components shall be designed so that the elastomeric
splicedconstructionshallbefreefromporosityandairpockets.
material is compressed to form a hydrostatic seal when the
Its surface shall be smooth and free from pitting, cracks,
joint is assembled. The couplings shall be of the types
blisters, air marks, or any other imperfections that affect its
described in 4.1.1 – 4.1.3.
performance in service. The flash extension shall not exceed
4.1.1 Type A—A coupling consisting of an elastomeric
1mm at any point where the presence of flash affects perfor-
gasket incorporating corrosion-resistant tension bands and
mance.
tightening mechanism. Couplings shall be fabricated without
6.4 Elastomericgasketsandinsertsshallbecompatiblewith
shear rings, with or without inserts, and with or without a
the dimensions and tolerances of the specific material to which
center stop.
it is designed to join.
4.1.2 Type B—A coupling consisting of an elastomeric
gasket incorporating a corrosion-resistant shear ring, tension
7. Clamp Assembly Requirements
bands, and tightening mechanism. Couplings shall be fabri-
7.1 All metallic components shall be of 300 series stainless
cated with shear rings, with or without inserts, and with or
steel conforming to the chemical composition requirements of
without a center stop (Note 1).
Specification A240/A240M. All metallic components made
4.1.3 Type C—Acoupling fabricated with elastomeric com-
fromroundstockshallbeof300seriesstainlesssteelconform-
pression seals.
ing to the requirements of Specification A493 (excluding
NOTE1—Theprovisionsofthisstandardarenotintendedtopreventthe
copper-bearing alloys).
useofanyalternatematerialormethodofconstruction,providedanysuch
alternate meets the requirements of this standard.
7.2 Clampassemblies,tensionbands,andtighteningmecha-
nisms shall conform to the performance requirements as set
5. Materials and Manufacture
forth in 10.2.
5.1 Elastomeric materials used in the manufacturing of
8. Dimensions
couplings and inserts shall comply with the requirements of
10.1 and Table 1.
8.1 Couplings and bushing dimensions shall be compatible
with the dimensions and tolerances of the specific material to
5.2 All metallic components shall be manufactured of 300
series stainless steel. which it is designed to join.
6. Elastomeric Gasket Requirements 9. Samplin
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: C1173 − 18 C1173 − 22
Standard Specification for
Flexible Transition Couplings for Underground Piping
Systems
This standard is issued under the fixed designation C1173; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This specification describes the properties of devices or assemblies suitable for use as flexible transition couplings, hereinafter
referred to as “couplings,” for underground drainage and sewer piping systems.
1.2 Couplings that may include bushings, inserts, or shear rings and Flexible transition couplings that conform to the requirements
of this standard are suitable for joining plain-end pipe or fittings. The pipe to be joined shall be of similar or dissimilar materials,
size, or both.
1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only and are not considered standard.
1.4 The ASTM standards referenced herein shall be considered mandatory.
1.5 The committee with jurisdiction over this standard is not aware of another comparable standard for materials covered in this
standard.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
A240/A240M Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and
for General Applications
A493 Specification for Stainless Steel Wire and Wire Rods for Cold Heading and Cold Forging
A644 Terminology Relating to Iron Castings
D395 Test Methods for Rubber Property—Compression Set
D412 Test Methods for Vulcanized Rubber and Thermoplastic Elastomers—Tension
D471 Test Method for Rubber Property—Effect of Liquids
D543 Practices for Evaluating the Resistance of Plastics to Chemical Reagents
This specification is under the jurisdiction of ASTM Committee A04 on Iron Castings and is the direct responsibility of Subcommittee A04.75 on Gaskets and Coupling
for Plumbing and Sewer Piping.
Current edition approved Feb. 1, 2018June 1, 2022. Published February 2018June 2022. Originally approved in 1991. Last previous edition approved in 20142018 as
C1173 – 10 (2014).C1173 – 18. DOI: 10.1520/C1173-18.10.1520/C1173-22.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1173 − 22
D573 Test Method for Rubber—Deterioration in an Air Oven
D624 Test Method for Tear Strength of Conventional Vulcanized Rubber and Thermoplastic Elastomers
D638 Test Method for Tensile Properties of Plastics
D1149 Test Methods for Rubber Deterioration—Cracking in an Ozone Controlled Environment
D2240 Test Method for Rubber Property—Durometer Hardness
D3045 Practice for Heat Aging of Plastics Without Load
D6147 Test Method for Vulcanized Rubber and Thermoplastic Elastomer—Determination of Force Decay (Stress Relaxation)
in Compression
3. Terminology
3.1 Definitions—For definitions of terms used in this standard, see Terminology A644.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 center stop, n—an integral part of the gasket centered on its axial length, intended to limit the insertion depth of the pipe
to be coupled.
3.2.2 clamp assembly, n—that portion of the coupling excluding the gasket.
3.2.3 coupling, n—the complete assembly.
3.2.4 fitting, n—parts of a pipeline other than straight pipe couplings or valves.
3.2.5 flexible transition couplings, n—devices used to form a leakproof joint between sections of plain-end pipe or fittings of the
same or different materials, of the same or different size, or any combination of materials or pipe sizes.
3.2.6 free torque, n—the torque value expressed in lbf·in./Nm when the clamp is tightened four revolutions of the screw nut; while
in the free state, this value does not include any breakaway effects due to staking or passage of the band ends beyond the screw
heads.
3.2.7 inserts, n—a bushing or ring placed into the coupling socket to accommodate pipe materials of differing outside diameters.
3.2.8 joint, n—the completed assembly of parts consisting of the flexible transition coupling and the joined pipes, or fittings, or
both.
3.2.9 lot, n—a specific quantity of similar material or collection of similar units from a common source; the quantity offered for
inspection and acceptance at any one time. A lot might comprise a shipment, batch, or similar quantity.
3.2.10 manufacturer, n—the entity that produces the coupling.
3.2.11 plain-end pipe, n—any pipe that does not include any bell, hub, threaded area, or other means of joining.
3.2.12 shear ring, n—an interior or exterior element which is used to span the distance between the pipe ends within a coupling
so as to provide increased resistance to axial displacement.
4. Classification
4.1 The couplings shall be permitted to have a center stop. The components shall be designed so that the elastomeric material is
compressed to form a hydrostatic seal when the joint is assembled. The couplings shall be of the types described in 4.1.1 – 4.1.3.
4.1.1 Type A—A coupling consisting of an elastomeric gasket incorporating corrosion-resistant tension bands and tightening
mechanism. Couplings shall be fabricated without shear rings, with or without inserts, and with or without a center stop.
C1173 − 22
4.1.2 Type B—A coupling consisting of an elastomeric gasket incorporating a corrosion-resistant shear ring, tension bands, and
tightening mechanism. Couplings shall be fabricated with shear rings, with or without inserts, and with or without a center stop
(Note 1).
4.1.3 Type C—A coupling fabricated with elastomeric compression seals.
NOTE 1—The provisions of this standard are not intended to prevent the use of any alternate material or method of construction, provided any such
alternate meets the requirements of this standard.
5. Materials and Manufacture
5.1 Elastomeric materials used in the manufacturing of couplings and inserts shall comply with the requirements of 10.1 and Table
1.
5.2 All metallic components shall be manufactured of 300 series stainless steel.
6. Elastomeric Gasket Requirements
6.1 The elastomeric gasket shall conform to the physical properties as specified in 5.1.
6.2 Elastomeric gaskets and inserts of single, multi-piece, or spliced construction shall show no signs of separation, peeling, or
other defects when tested in accordance with Section 9.
6.3 Elastomeric gaskets and inserts of single, multi-piece, or spliced construction shall be free from porosity and air pockets. Its
surface shall be smooth and free from pitting, cracks, blisters, air marks, or any other imperfections that affect its performance in
service. The flash extension shall not exceed 1 mm at any point where the presence of flash affects performance.
6.4 Elastomeric gaskets and inserts shall be compatible with the dimensions and tolerances of the specific material to which it is
designed to join.
TABLE 1 Test Requirements
Physical ASTM Test
Properties
Requirements Method
Elastomeric materials
Hardness, nominal shore “A” durometer as 50 – 75 D2240
specified by the coupling manufacturer
Hardness, nominal shore “A” durometer as 50–75 D2240
specified by the coupling manufacturer
Hardness, nominal shore “D” durometer as 35 – 45 D2240
specified by the coupling manufacturer
Hardness, nominal shore “D” durometer as 35–45 D2240
specified by the coupling manufacturer
Tensile strength, min psi (KPa) 1000 (6894) D412, Die C,
Fig. 2 or D638
Elongation at rupture, min, % 200 D412, Die C,
Fig. 2 or D638
Heat aging, 70 h, 158 ± 3.6 °F (70 ± 2 °C) D573 or D3045
Hardness increase, maximum Durometer 10
points
Change in tensile strength, max, % 25
Change in elongation, max, % 35
Ozone resistance no cracks D1149
At 20 % elongation
For 100 h at 104 ± 3.6 °F (40 ± 2 °C)
With 50 parts per 100 million
Water absorption, weight gain, %, max 20 D471
Chemical resistance, 48 h, 74 ± 3.6 °F (23 no weight loss D543
± 2 °C)
Compression set, max, % 25 D395 Method B
Stress relaxation, min. % force retention 30 D6147
Tear strength, min, lbf/in. (N/cm) 150 (268.5) D624 Die C
C1173 − 22
7. Clamp Assembly Requirements
7.1 All metallic components shall be of 300 series stainless steel conforming to the chemical composition requirements of
Specification A240/A240M. All metallic components made from round stock shall be of 300 series stainless steel conforming to
the requirements of Specification A493 (excluding copper-bea
...