ASTM B88M-20

Standard Specification for Seamless Copper Water Tube (Metric)

ABSTRACT
This specification covers seamless copper alloy water tubes for general plumbing and similar applications in fluid conveyance. These water tubes made from UNS C10200, C12000, and C12200 copper alloys are commonly used with solder, flared, or compression-type fittings. The materials should be cold-drawn to size and the tubes finished by cold working and annealing to produce the required temper and surface finish. When tubes are furnished in coils, annealing is done after coiling, while those furnished in straight lengths should be in the drawn temper. The numerical values in this specification are not presented in inch-pound units, but rather, in metric or SI units only.
SIGNIFICANCE AND USE
16.1 For purposes of determining compliance with the specified limits for requirements of the properties listed in Table 8, an observed value or calculated value shall be rounded as indicated in accordance with the rounding method of Practice E29.
SCOPE
1.1 This specification covers seamless copper water tube suitable for general plumbing, similar applications for the conveyance of fluids, and commonly used with solder, flared, or compression-type fittings. The type of copper water tube suitable for any particular application is determined by the internal or external fluid pressure, by the installation and service conditions, and by local requirements. Means of joining or bending are also factors that affect the selection of the type of tube to be used.2  
Note 1: Annealed tube is suitable for use with flared or compression fittings, and with solder-type fittings, provided rounding and sizing of the tube ends is performed where needed.
Note 2: Drawn temper tube is suitable for use with solder-type fittings. Types A and B tube, in the drawn temper, are suitable for use with certain types and sizes of compression fittings.  
1.2 The tube shall be produced from the following coppers, and the manufacturer has the option to supply any one of them, unless otherwise specified:    
Copper
UNS No.  
Previously Used
Designation  
Description    
C10200  
OF  
Oxygen free without
residual deoxidants  
C12000  
DLP  
Phosphorus deoxidized,
low residual phosphorus  
C12200  
DHP  
Phosphorus deoxidized,
high residual phosphorus  
1.3 The assembly of copper plumbing or fire sprinkler systems by soldering is described in Practice B828.  
1.4 Solders for joining copper potable water or fire sprinkler systems are covered by Specification B32. The requirements for acceptable fluxes for these systems are covered by Specification B813.  
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
Note 3: This specification is the SI companion to Specification B88.  
1.6 The following safety hazards caveat pertains only to the test methods portion, Section 15, of this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.7 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-Mar-2020
• ICS: 23.040.15 - Non-ferrous metal pipes
• Technical Committee: B05 - Copper and Copper Alloys
• Drafting Committee: B05.04 - Pipe and Tube

Relations

• Replaces: ASTM B88M-18 - Standard Specification for Seamless Copper Water Tube (Metric)
• Effective Date: 01-Apr-2020
• Refers: ASTM E8/E8M-24 - Standard Test Methods for Tension Testing of Metallic Materials
• Effective Date: 01-Jan-2024
• Refers: ASTM B828-23 - Standard Practice for Making Capillary Joints by Soldering of Copper and Copper Alloy Tube and Fittings
• Effective Date: 01-Dec-2023
• Refers: ASTM B846-19a - Standard Terminology for Copper and Copper Alloys
• Effective Date: 01-Aug-2019
• Refers: ASTM B577-19 - Standard Test Methods for Detection of Cuprous Oxide (Hydrogen Embrittlement Susceptibility) in Copper
• Effective Date: 01-Apr-2019
• Refers: ASTM B846-19 - Standard Terminology for Copper and Copper Alloys
• Effective Date: 01-Jan-2019
• Refers: ASTM B601-18a - Standard Classification for Temper Designations for Copper and Copper Alloys—Wrought and Cast
• Effective Date: 01-Oct-2018
• Refers: ASTM E18-18 - Standard Test Methods for Rockwell Hardness of Metallic Materials
• Effective Date: 01-Jul-2018
• Refers: ASTM E243-18 - Standard Practice for Electromagnetic (Eddy Current) Examination of Copper and Copper-Alloy Tubes
• Effective Date: 01-Jun-2018
• Refers: ASTM B601-18 - Standard Classification for Temper Designations for Copper and Copper Alloys—Wrought and Cast
• Effective Date: 01-Mar-2018
• Refers: ASTM E18-17 - Standard Test Methods for Rockwell Hardness of Metallic Materials
• Effective Date: 01-Jul-2017
• Refers: ASTM B88-16 - Standard Specification for Seamless Copper Water Tube
• Effective Date: 01-Oct-2016
• Refers: ASTM B601-16 - Standard Classification for Temper Designations for Copper and Copper Alloys—Wrought and Cast
• Effective Date: 01-Oct-2016
• Refers: ASTM E8/E8M-16 - Standard Test Methods for Tension Testing of Metallic Materials
• Effective Date: 15-Jul-2016
• Refers: ASTM B828-16 - Standard Practice for Making Capillary Joints by Soldering of Copper and Copper Alloy Tube and Fittings
• Effective Date: 01-Jun-2016

Overview

ASTM B88M-20 - Standard Specification for Seamless Copper Water Tube (Metric) is an internationally recognized specification issued by ASTM International. The standard covers seamless copper alloy water tubes manufactured using metric (SI) units, suitable for general plumbing and similar fluid conveyance applications. These copper tubes, produced from alloys UNS C10200, C12000, or C12200, are widely used in both domestic and commercial plumbing systems, including potable water and fire sprinkler installations.

The specification addresses the manufacture, chemical composition, mechanical properties, permissible dimensional variances, and quality assurance protocols required for seamless copper water tubes. Tubes may be supplied in various tempers and forms, including coils (annealed) or straight lengths (primarily drawn temper).

Key Topics

• Material Requirements: The standard specifies copper tubes made from:

  • UNS C10200 (oxygen-free)
  • UNS C12000 (phosphorus-deoxidized, low phosphorus)
  • UNS C12200 (phosphorus-deoxidized, high phosphorus)

• Manufacturing Processes:

  • Tubes are cold-drawn to size and finished by cold working and annealing as required to meet temper and surface finish specifications.
  • Coiled tubes are annealed after coiling; straight lengths are usually in drawn temper.

• Dimensional Standards:

  • Metric dimensions only; no inch-pound units.
  • Types A, B, and C with specified wall thickness tolerances and outside diameters.

• Joining Capabilities:

  • Tubes are suitable for installation with solder, flared, or compression-type fittings.
  • Annealed tubes are suitable for flaring and compression; drawn tubes are primarily for soldered connections.

• Quality Assurance:

  • Non-destructive eddy-current testing is required for most tube sizes.
  • Mechanical and chemical properties are tested per referenced ASTM standards.
  • Specific tolerances on roundness, length, mass, and squareness of cut are detailed.

• Product Identification:

  • Tubes marked with manufacturer’s name/trademark, copper type, specification number, and color coding for types (green for A, blue for B, red for C).

Applications

Seamless copper water tubes conforming to ASTM B88M-20 are essential in a wide array of fluid conveyance applications, benefiting from copper’s durability, corrosion resistance, and compatibility with various joining techniques. Typical applications include:

• General Plumbing: Piping systems for potable water in residential, commercial, and institutional buildings.
• Fire Sprinkler Systems: Copper tube used in fire suppression installations, often specified by building codes.
• HVAC Systems: Fluid transport for heating, cooling, and ventilation, including chilled water and hot water loops.
• Industrial Fluid Handling: Suitable for non-potable fluids, process piping, and transport of liquids where clean and reliable conveyance is required.

Installers and engineers choose copper tubing per ASTM B88M-20 for its long service life, ease of installation, and standardized sizing, making it highly suitable for both new construction and retrofit projects.

Related Standards

The B88M-20 standard references several related ASTM specifications and test methods to support consistent quality and performance:

• ASTM B88: The inch-pound companion to B88M, covering seamless copper water tube with imperial dimensions.
• ASTM B32: Specification for solder metals.
• ASTM B813: Specification for soldering fluxes used with copper and copper alloy tubes.
• ASTM B828: Practice for making capillary joints by soldering copper tube and fittings.
• ASTM B153, B577, E8/E8M, E18, E112: Address mechanical testing, chemical analysis, hardness, and grain size.

These related standards help ensure that copper tube installations are reliable, safe, and conform to consistent international quality benchmarks.

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Keywords: ASTM B88M-20, seamless copper water tube, metric copper tube, copper plumbing standards, UNS C10200, C12000, C12200, copper fluid conveyance, plumbing tube specification, copper pipe metric, copper alloy standard, ASTM copper tube

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:B88M −20
Standard Specification for
Seamless Copper Water Tube (Metric)
This standard is issued under the fixed designation B88M; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope* 1.5 The values stated in SI units are to be regarded as
standard. No other units of measurement are included in this
1.1 This specification covers seamless copper water tube
standard.
suitable for general plumbing, similar applications for the
NOTE 3—This specification is the SI companion to Specification B88.
conveyance of fluids, and commonly used with solder, flared,
1.6 The following safety hazards caveat pertains only to the
or compression-type fittings. The type of copper water tube
test methods portion, Section 15, of this specification: This
suitable for any particular application is determined by the
standard does not purport to address all of the safety concerns,
internal or external fluid pressure, by the installation and
if any, associated with its use. It is the responsibility of the user
serviceconditions,andbylocalrequirements.Meansofjoining
of this standard to establish appropriate safety, health, and
or bending are also factors that affect the selection of the type
environmental practices and determine the applicability of
of tube to be used.
regulatory limitations prior to use.
NOTE 1—Annealed tube is suitable for use with flared or compression
1.7 This international standard was developed in accor-
fittings, and with solder-type fittings, provided rounding and sizing of the
dance with internationally recognized principles on standard-
tube ends is performed where needed.
ization established in the Decision on Principles for the
NOTE2—Drawntempertubeissuitableforusewithsolder-typefittings.
TypesAand B tube, in the drawn temper, are suitable for use with certain Development of International Standards, Guides and Recom-
types and sizes of compression fittings.
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
1.2 The tube shall be produced from the following coppers,
and the manufacturer has the option to supply any one of them,
2. Referenced Documents
unless otherwise specified:
Copper Previously Used Description 2.1 The following documents of the issue in effect on date
UNS No. Designation
of material purchase form a part of this specification to the
extent referenced herein:
C10200 OF Oxygen free without
residual deoxidants 3
2.2 ASTM Standards:
C12000 DLP Phosphorus deoxidized,
B32 Specification for Solder Metal
low residual phosphorus
C12200 DHP Phosphorus deoxidized,
B88 Specification for Seamless Copper Water Tube
high residual phosphorus
B153 Test Method for Expansion (Pin Test) of Copper and
1.3 The assembly of copper plumbing or fire sprinkler
Copper-Alloy Pipe and Tubing
systems by soldering is described in Practice B828.
B577 Test Methods for Detection of Cuprous Oxide (Hydro-
gen Embrittlement Susceptibility) in Copper
1.4 Soldersforjoiningcopperpotablewaterorfiresprinkler
B601 ClassificationforTemperDesignationsforCopperand
systems are covered by Specification B32. The requirements
Copper Alloys—Wrought and Cast
for acceptable fluxes for these systems are covered by Speci-
B813 Specification for Liquid and Paste Fluxes for Solder-
fication B813.
ing of Copper and Copper Alloy Tube
B828 Practice for Making Capillary Joints by Soldering of
Copper and Copper Alloy Tube and Fittings
ThisspecificationisunderthejurisdictionofASTMCommitteeB05onCopper
B846 Terminology for Copper and Copper Alloys
and CopperAlloys and is the direct responsibility of Subcommittee B05.04 on Pipe
and Tube.
B900 Practice for Packaging of Copper and Copper Alloy
Current edition approved April 1, 2020. Published May 2020. Originally
approved in 1983. Last previous edition approved in 2018 as B88M-18. DOI:
10.1520/B0088M-20.
2 3
The UNS system for copper and copper alloys (see Practice E527) is a simple For referenced ASTM standards, visit the ASTM website, www.astm.org, or
expansion of the former standard designation system accomplished by the addition contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
of a prefix “C” and a suffix “00.”The suffix is permitted to be used to accommodate Standards volume information, refer to the standard’s Document Summary page on
composition variations of the base alloy. the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B88M−20
Mill Products for U.S. Government Agencies 4. Ordering Information
E8/E8M Test Methods for Tension Testing of Metallic Ma-
4.1 Include the following information for material ordered
terials
under this specification.
E18 Test Methods for Rockwell Hardness of Metallic Ma-
4.1.1 ASTM designation and year of issue (for example,
terials
B88M – 03);
E29 Practice for Using Significant Digits in Test Data to
4.1.2 Copper UNS No. (not necessary unless a specific
Determine Conformance with Specifications
copper is desired),
E53 Test Method for Determination of Copper in Unalloyed
4.1.3 Nominal or standard size (Column 1 of Table 1) and
Copper by Gravimetry
whether Type A, B, or C (Section 3);
E62 Test Methods for Chemical Analysis of Copper and
4.1.4 Temper (Section 7);
CopperAlloys(PhotometricMethods)(Withdrawn2010)
4.1.5 Length (see 11.5);
E112 Test Methods for Determining Average Grain Size
4.1.6 How furnished: straight or coils;
E243 Practice for Electromagnetic (Eddy Current) Examina-
4.1.7 Quantity (pieces) of each size and type;
tion of Copper and Copper-Alloy Tubes
4.1.8 Inaddition,whenmaterialispurchasedforagenciesof
E255 Practice for Sampling Copper and Copper Alloys for
the U.S. Government, it shall conform to the Supplementary
the Determination of Chemical Composition
Requirements as defined herein when specified in the contract
E527 Practice for Numbering Metals and Alloys in the
or purchase order.
Unified Numbering System (UNS)
4.2 The following options are available and shall be speci-
fied in the contract or purchase order when required:
3. Terminology
4.2.1 Tension test (Section 8),
3.1 Definitions—For definitions of terms related to copper
4.2.2 Grain size determination (Section 8),
and copper alloys, refer to Terminology B846.
4.2.3 Expansion test (9.1), and
3.2 Definitions of Terms Specific to This Standard:
4.2.4 Microscopical Examination for Hydrogen Embrittle-
3.2.1 tube, copper water, n—a seamless copper tube con-
ment, Procedure B (9.3.2).
forming to the particular metric dimensions commercially
known as Copper Water Tube and designated as Types A, B, 5. Materials and Manufacture
and C.
5.1 The material shall be of such quality and purity that the
finished product shall have the properties and characteristics
prescribed in this specification, and shall be cold worked to
The last approved version of this historical standard is referenced on
size.
www.astm.org.
TABLE 1 Dimensions, Mass, and Tolerances in Diameter and Wall Thickness for Metric Copper Water Tube Sizes
(All tolerances are plus and minus except as otherwise indicated.)
Average Outside
Wall Thickness and Tolerances, mm Theoretical Mass, kg/m
A
Diameter Tolerance, mm
Nominal or Outside
Standard Diameter, Type A Type B Type C
Size, mm mm
Annealed Drawn Type A Type B Type C
Wall Toler- Wall Toler- Wall Toler-
B B B
Thickness ance Thickness ance Thickness ance
C
6 6.0 0.05 0.03 0.80 0.08 0.70 0.07 0.60 0.117 0.104 0.091
C
8 8.0 0.05 0.03 0.90 0.09 0.80 0.08 0.60 0.179 0.162 0.125
C
10 10.0 0.05 0.03 0.90 0.09 0.80 0.08 0.60 0.230 0.207 0.158
12 12.0 0.06 0.03 1.2 0.1 0.90 0.09 0.60 0.06 0.364 0.280 0.192
15 15.0 0.06 0.03 1.2 0.1 1.0 0.1 0.70 0.07 0.465 0.393 0.281
18 18.0 0.06 0.03 1.2 0.1 1.0 0.1 0.70 0.07 0.566 0.477 0.340
22 22.0 0.06 0.03 1.6 0.15 1.1 0.1 0.80 0.08 0.917 0.646 0.476
28 28.0 0.07 0.04 1.6 0.15 1.2 0.1 0.90 0.09 1.19 0.903 0.685
35 35.0 0.10 0.04 1.6 0.15 1.4 0.15 1.1 0.1 1.50 1.32 1.05
42 42.0 0.10 0.05 1.8 0.2 1.5 0.15 1.2 0.1 2.03 1.71 1.37
54 54.0 0.10 0.05 2.1 0.2 1.7 0.15 1.5 0.15 3.06 2.50 2.21
67 67.0 0.12 0.05 2.4 0.25 2.0 0.2 1.6 0.15 4.35 3.65 2.94
79 79.0 0.12 0.05 2.8 0.3 2.3 0.25 1.8 0.2 5.99 4.95 3.90
105 105.0 0.12 0.05 3.4 0.35 2.8 0.3 2.4 0.25 9.70 8.04 6.92
130 130.0 0.12 0.05 4.0 0.4 3.1 0.3 2.7 0.25 14.2 11.0 9.65
156 156.0 0.12 0.05 4.8 0.5 3.5 0.35 3.1 0.3 20.3 15.0 13.3
206 206.0 0.15 + 0.05 6.8 0.7 5.0 0.5 4.3 0.45 38.0 28.2 24.4
−0.10
257 257.0 0.20 + 0.05 8.5 0.85 6.3 0.65 5.4 0.55 59.3 44.4 38.2
−0.15
308 308.0 0.20 + 0.05 10.3 1.0 7.1 0.7 6.4 0.65 86.1 60.0 54.2
−0.15
A
The average outside diameter of a tube is the average of the maximum and minimum outside diameter, as determined at any one cross section of the tube.
B
Maximum deviation at any one point.
C
Indicates that the material is not generally available or that no tolerance has been established.
B88M−20
5.2 The tube shall be finished by such cold-working and of one of the lengths for a flattening test. This 100 mm test
annealing operations as are necessary to produce the required specimen shall be flattened so that a gage set at three times the
temper and surface finish. wall thickness will pass over the tube freely throughout the
flattened part. The tube so tested shall develop no cracks or
5.3 Tube furnished in coils shall be annealed.
flaws visible to the unaided eye as a result of this test. In
5.4 Tube furnished in straight lengths shall normally be in
makingtheflatteningtesttheelementsshallbeslowlyflattened
the drawn temper. Upon agreement between the manufacturer
by one stroke of the press.
or supplier and the purchaser, the manufacturer shall have the
9.3 Microscopical Examination for Susceptibility to Hydro-
option to supply annealed straight length tubing.
gen Embrittlement:
9.3.1 Tubes furnished in Copper UNS No. C10200 and
6. Chemical Composition
C12000 shall be essentially free of cuprous oxide as deter-
6.1 The material shall conform to the chemical composition
mined by Procedure A of Test Methods B577. When Copper
requirements in Table 2 for the specific type of copper.
UNS No. C12200 is supplied, examination is not required. In
6.2 These specification limits do not preclude the presence
case of a dispute, Procedure C of Test Methods B577 shall be
of other elements. When included in the contract or purchase
used as the referee method.
order, and agreed upon by the manufacturer or supplier and the
9.3.2 Tubes furnished in all coppers shall be capable of
purchaser, limits shall be established and analysis required for
passing the embrittlement test specified in Procedure B of Test
unnamed elements.
Methods B577. The actual performance of the test is not
required unless specifically requested in the ordering docu-
7. Temper
ment. In case of a dispute, Procedure C of Test Methods B577
7.1 The copper water tube shall be furnished in the tempers
shall be used as the referee method.
designated below. Current designations as defined in Classifi-
10. Nondestructive Testing
cation B601 are as follows:
10.1 Eddy-Current Test—Each tube up to and including 79
Annealed-O
mm in outside diameter shall be subjected to an eddy-current
Drawn-H
test. Testing shall follow the procedure of Practice E243,
8. Mechanical Properties
except the determination of “end effect” is not required. Tubes
8.1 The tube shall conform to the mechanical property
shall be passed through an eddy current test unit adjusted to
requirementsprescribedinTable3.Tensiontestsandgrainsize provide information on the suitability of the tube for the
determinations need not be made except when indicated by the
intended application.
purchaseratthetimeofplacingtheorder.Aconvenientmethod 10.1.1 The testing of tube of dimensions beyond the capa-
ofindicatingthatthesetestsaretobemadeistostatethat“Test
bilities of the eddy-current test apparatus shall be subject to
Procedure T is required” (see 4.2.1). Where agreement on the negotiation between the producer and the purchaser.
Rockwell hardness tests cannot be reached, the tensile strength
10.1.2 Notch-depth standards, rounded to the nearest 0.03
and grain-size requirements of Table 3 shall be the basis for mm, shall be 22 % of the wall thickness. The notch-depth
acceptance or rejection.
toleranceshallbe 60.01mm.Alternatively,attheoptionofthe
manufacturer using speed insensitive eddy-current units that
9. Performance Requirements
are equipped to select a fraction of the maximum unbalance
9.1 Expansion Test—The annealed (O) tube shall be capable signal, the following percent maximum unbalance signals shall
of being expanded in accordance with Test Method B153 with be used:
an expansion of the outside diameter in the following amount:
Unbalance Signal
Nominal or Standard Tube Size, mm Magnitude, max %
Nominal or Expansion of
Standard Size, mm Outside Diameter, %
Up to and incl 12 0.2
15 to 54, incl 0.3
15 and under 40
Over 54 to 79, incl 0.4
Over 15 30
10.1.3 Tubes that do not actuate the signalling device of the
The expanded tube shall show no cracking or rupture visible
eddy-current testers shall be considered as conforming to the
to the unaided eye.
requirements of this test. Tubes with discontinuities indicated
9.2 Flattening Test—As an alternative to the expansion test
by the testing unit shall, at the option of the manufacturer, be
for tube standard sizes 105 mm and over in the annealed
reexamined or retested to determine whether the discontinuity
condition, a section 100 mm in length shall be cut from the end
is cause for rejection. Signals that are found to have been
causedbyminormechanicaldamage,soil,ormoistureshallnot
TABLE 2 Chemical Composition—Weight %
be cause for rejection of the tubes provided the tube dimen-
Element Copper UNS No. sions are still within the prescribed limits and the tube is
A
C10200 C12000 C12200
suitable for its intended application.
B
Copper, min 99.95 99.90 99.9
Phosphorus . 0.004–0.012 0.015–0.040
11. Dimensions, Mass, and Permissible Variations
A
Oxygen shall be 10 ppm max.
B 11.1 For the purpose of determining conformance with the
Copper + silver.
dimensional requirements prescribed in this specification, any
B88M−20
TABLE 3 Mechanical Property Requirements
A
Temper Designation Rockwell Hardness Tensile Strength, Average Grain Size,
Form
Standard Former Scale Value min, MPa mm
OS060 annealed coils F 50 max 200 0.040 min
OS035 annealed straight lengths F 55 max 200 0.025 min
H58 drawn drawn 30 T 30 min 250 .
A
Rockwell hardness tests shall be made on the inside surfaces of the tube. When suitable equipment is not available for determining the specified Rockwell hardness,
other Rockwell scales and values shall be specified subject to agreement between the purchaser and the supplier.
TABLE 5 Nominal or Standard Lengths and Tolerances
measured value outside the specified li
...

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: B88M − 18 B88M − 20
Standard Specification for
Seamless Copper Water Tube (Metric)
This standard is issued under the fixed designation B88M; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope*
1.1 This specification covers seamless copper water tube suitable for general plumbing, similar applications for the conveyance
of fluids, and commonly used with solder, flared, or compression-type fittings. The type of copper water tube suitable for any
particular application is determined by the internal or external fluid pressure, by the installation and service conditions, and by local
requirements. Means of joining or bending are also factors that affect the selection of the type of tube to be used.
NOTE 1—Annealed tube is suitable for use with flared or compression fittings, and with solder-type fittings, provided rounding and sizing of the tube
ends is performed where needed.
NOTE 2—Drawn temper tube is suitable for use with solder-type fittings. Types A and B tube, in the drawn temper, are suitable for use with certain
types and sizes of compression fittings.
1.2 The tube shall be produced from the following coppers, and the manufacturer has the option to supply any one of them,
unless otherwise specified:
Copper Previously Used Description
UNS No. Designation
C10200 OF Oxygen free without
residual deoxidants
C12000 DLP Phosphorus deoxidized,
low residual phosphorus
C12200 DHP Phosphorus deoxidized,
high residual phosphorus
1.3 The assembly of copper plumbing or fire sprinkler systems by soldering is described in Practice B828.
1.4 Solders for joining copper potable water or fire sprinkler systems are covered by Specification B32. The requirements for
acceptable fluxes for these systems are covered by Specification B813.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
NOTE 3—This specification is the SI companion to Specification B88.
1.6 The following safety hazards caveat pertains only to the test methods portion, Section 15, of this specification: This standard
does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this
standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory
limitations prior to use.
1.7 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 The following documents of the issue in effect on date of material purchase form a part of this specification to the extent
referenced herein:
This specification is under the jurisdiction of ASTM Committee B05 on Copper and Copper Alloys and is the direct responsibility of Subcommittee B05.04 on Pipe and
Tube.
Current edition approved March 1, 2018April 1, 2020. Published March 2018May 2020. Originally approved in 1983. Last previous edition approved in 20162018 as
B88M – 16.B88M-18. DOI: 10.1520/B0088M-18.10.1520/B0088M-20.
The UNS system for copper and copper alloys (see Practice E527) is a simple expansion of the former standard designation system accomplished by the addition of a
prefix “C” and a suffix “00.” The suffix is permitted to be used to accommodate composition variations of the base alloy.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B88M − 20
2.2 ASTM Standards:
B32 Specification for Solder Metal
B88 Specification for Seamless Copper Water Tube
B153 Test Method for Expansion (Pin Test) of Copper and Copper-Alloy Pipe and Tubing
B577 Test Methods for Detection of Cuprous Oxide (Hydrogen Embrittlement Susceptibility) in Copper
B601 Classification for Temper Designations for Copper and Copper Alloys—Wrought and Cast
B813 Specification for Liquid and Paste Fluxes for Soldering of Copper and Copper Alloy Tube
B828 Practice for Making Capillary Joints by Soldering of Copper and Copper Alloy Tube and Fittings
B846 Terminology for Copper and Copper Alloys
B900 Practice for Packaging of Copper and Copper Alloy Mill Products for U.S. Government Agencies
E8/E8M Test Methods for Tension Testing of Metallic Materials
E18 Test Methods for Rockwell Hardness of Metallic Materials
E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
E53 Test Method for Determination of Copper in Unalloyed Copper by Gravimetry
E62 Test Methods for Chemical Analysis of Copper and Copper Alloys (Photometric Methods) (Withdrawn 2010)
E112 Test Methods for Determining Average Grain Size
E243 Practice for Electromagnetic (Eddy Current) Examination of Copper and Copper-Alloy Tubes
E255 Practice for Sampling Copper and Copper Alloys for the Determination of Chemical Composition
E527 Practice for Numbering Metals and Alloys in the Unified Numbering System (UNS)
3. Terminology
3.1 Definitions—For definitions of terms related to copper and copper alloys, refer to Terminology B846.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 tube, copper water, n—a seamless copper tube conforming to the particular metric dimensions commercially known as
Copper Water Tube and designated as Types A, B, and C.
4. Ordering Information
4.1 Include the following information for material ordered under this specification.
4.1.1 ASTM designation and year of issue (for example, B88M – 03),);
4.1.2 Copper UNS No. (not necessary unless a specific copper is desired),
4.1.3 Nominal or standard size (Column 1 of Table 1) and whether Type A, B, or C (Section 3),);
4.1.4 Temper (Section 7),);
4.1.5 Length (see 11.5),);
4.1.6 How furnished: straight or coils,coils;
4.1.7 Quantity (pieces) of each size and type,type;
4.1.8 In addition, when material is purchased for agencies of the U.S. Government, it shall conform to the Supplementary
Requirements as defined herein when specified in the contract or purchase order.
4.2 The following options are available and shall be specified in the contract or purchase order when required:
4.2.1 Tension test (Section 8),
4.2.2 Grain size determination (Section 8),
4.2.3 Expansion test (9.1), and
4.2.4 Microscopical Examination for Hydrogen Embrittle-ment, Procedure B (9.3.2).
5. Materials and Manufacture
5.1 The material shall be of such quality and purity that the finished product shall have the properties and characteristics
prescribed in this specification, and shall be cold worked to size.
5.2 The tube shall be finished by such cold-working and annealing operations as are necessary to produce the required temper
and surface finish.
5.3 Tube furnished in coils shall be annealed.
5.4 Tube furnished in straight lengths shall normally be in the drawn temper. Upon agreement between the manufacturer or
supplier and the purchaser, the manufacturer shall have the option to supply annealed straight length tubing.
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’sstandard’s Document Summary page on the ASTM website.
The last approved version of this historical standard is referenced on www.astm.org.
B88M − 20
TABLE 1 Dimensions, Mass, and Tolerances in Diameter and Wall Thickness for Metric Copper Water Tube Sizes
(All tolerances are plus and minus except as otherwise indicated.)
Average Outside
Wall Thickness and Tolerances, mm Theoretical Mass, kg/m
A
Diameter Tolerance, mm
Nominal or Outside
Standard Diameter, Type A Type B Type C
Size, mm mm
Annealed Drawn Type A Type B Type C
Wall Toler- Wall Toler- Wall Toler-
B B B
Thickness ance Thickness ance Thickness ance
C
6 6.0 0.05 0.03 0.80 0.08 0.70 0.07 0.60 0.117 0.104 0.091
C
8 8.0 0.05 0.03 0.90 0.09 0.80 0.08 0.60 0.179 0.162 0.125
C
10 10.0 0.05 0.03 0.90 0.09 0.80 0.08 0.60 0.230 0.207 0.158
12 12.0 0.06 0.03 1.2 0.1 0.90 0.09 0.60 0.06 0.364 0.280 0.192
15 15.0 0.06 0.03 1.2 0.1 1.0 0.1 0.70 0.07 0.465 0.393 0.281
18 18.0 0.06 0.03 1.2 0.1 1.0 0.1 0.70 0.07 0.566 0.477 0.340
22 22.0 0.06 0.03 1.6 0.15 1.1 0.1 0.80 0.08 0.917 0.646 0.476
28 28.0 0.07 0.04 1.6 0.15 1.2 0.1 0.90 0.09 1.19 0.903 0.685
35 35.0 0.10 0.04 1.6 0.15 1.4 0.15 1.1 0.1 1.50 1.32 1.05
42 42.0 0.10 0.05 1.8 0.2 1.5 0.15 1.2 0.1 2.03 1.71 1.37
54 54.0 0.10 0.05 2.1 0.2 1.7 0.15 1.5 0.15 3.06 2.50 2.21
67 67.0 0.12 0.05 2.4 0.25 2.0 0.2 1.6 0.15 4.35 3.65 2.94
79 79.0 0.12 0.05 2.8 0.3 2.3 0.25 1.8 0.2 5.99 4.95 3.90
105 105.0 0.12 0.05 3.4 0.35 2.8 0.3 2.4 0.25 9.70 8.04 6.92
130 130.0 0.12 0.05 4.0 0.4 3.1 0.3 2.7 0.25 14.2 11.0 9.65
156 156.0 0.12 0.05 4.8 0.5 3.5 0.35 3.1 0.3 20.3 15.0 13.3
206 206.0 0.15 + 0.05 6.8 0.7 5.0 0.5 4.3 0.45 38.0 28.2 24.4
−0.10
257 257.0 0.20 + 0.05 8.5 0.85 6.3 0.65 5.4 0.55 59.3 44.4 38.2
−0.15
308 308.0 0.20 + 0.05 10.3 1.0 7.1 0.7 6.4 0.65 86.1 60.0 54.2
−0.15
A
The average outside diameter of a tube is the average of the maximum and minimum outside diameter, as determined at any one cross section of the tube.
B
Maximum deviation at any one point.
C
Indicates that the material is not generally available or that no tolerance has been established.
6. Chemical Composition
6.1 The material shall conform to the chemical composition requirements in Table 2 for the specific type of copper.
6.2 These specification limits do not preclude the presence of other elements. When included in the contract or purchase order,
and agreed upon by the manufacturer or supplier and the purchaser, limits shall be established and analysis required for unnamed
elements.
7. Temper
7.1 The copper water tube shall be furnished in the tempers designated below. Current designations as defined in Classification
B601 are as follows:
Annealed-O
Drawn-H
8. Mechanical Properties
8.1 The tube shall conform to the mechanical property requirements prescribed in Table 3. Tension tests and grain size
determinations need not be made except when indicated by the purchaser at the time of placing the order. A convenient method
of indicating that these tests are to be made is to state that “Test Procedure T is required” (see 4.2.1). Where agreement on the
Rockwell hardness tests cannot be reached, the tensile strength and grain-size requirements of Table 3 shall be the basis for
acceptance or rejection.
9. Performance Requirements
9.1 Expansion Test—The annealed (O) tube shall be capable of being expanded in accordance with Test Method B153 with an
expansion of the outside diameter in the following amount:
TABLE 2 Chemical Composition—Weight %
Element Copper UNS No.
A
C10200 C12000 C12200
B
Copper, min 99.95 99.90 99.9
Phosphorus . 0.004–0.012 0.015–0.040
A
Oxygen shall be 10 ppm max.
B
Copper + silver.
B88M − 20
TABLE 3 Mechanical Property Requirements
A
Temper Designation Rockwell Hardness Tensile Strength, Average Grain Size,
Form
min, MPa mm
Standard Former Scale Value
OS060 annealed coils F 50 max 200 0.040 min
OS035 annealed straight lengths F 55 max 200 0.025 min
H58 drawn drawn 30 T 30 min 250 .
A
Rockwell hardness tests shall be made on the inside surfaces of the tube. When suitable equipment is not available for determining the specified Rockwell hardness,
other Rockwell scales and values shall be specified subject to agreement between the purchaser and the supplier.
Nominal or Expansion of
Standard Size, mm Outside Diameter, %
15 and under 40
Over 15 30
The expanded tube shall show no cracking or rupture visible to the unaided eye.
9.2 Flattening Test—As an alternative to the expansion test for tube standard sizes 105 mm and over in the annealed condition,
a section 100 mm in length shall be cut from the end of one of the lengths for a flattening test. This 100-mm 100 mm test specimen
shall be flattened so that a gage set at three times the wall thickness will pass over the tube freely throughout the flattened part.
The tube so tested shall develop no cracks or flaws visible to the unaided eye as a result of this test. In making the flattening test
the elements shall be slowly flattened by one stroke of the press.
9.3 Microscopical Examination for Susceptibility to Hydrogen Embrittlement:
9.3.1 Tubes furnished in Copper UNS No. C10200 and C12000 shall be essentially free of cuprous oxide as determined by
Procedure A of Test Methods B577. When Copper UNS No. C12200 is supplied, examination is not required. In case of a dispute,
Procedure C of Test Methods B577 shall be used as the referee method.
9.3.2 Tubes furnished in all coppers shall be capable of passing the embrittlement test specified in Procedure B of Test Methods
B577. The actual performance of the test is not required unless specifically requested in the ordering document. In case of a dispute,
Procedure C of Test Methods B577 shall be used as the referee method.
10. Nondestructive Testing
10.1 Eddy-Current Test—Each tube up to and including 79 mm in outside diameter shall be subjected to an eddy-current test.
Testing shall follow the procedure of Practice E243, except the determination of “end effect” is not required. Tubes shall be passed
through an eddy current test unit adjusted to provide information on the suitability of the tube for the intended application.
10.1.1 The testing of tube of dimensions beyond the capabilities of the eddy-current test apparatus shall be subject to negotiation
between the producer and the purchaser.
10.1.2 Notch-depth standards, rounded to the nearest 0.03 mm, shall be 22 % of the wall thickness. The notch-depth tolerance
shall be 60.01 mm. Alternatively, at the option of the manufacturer using speed insensitive eddy-current units that are equipped
to select a fraction of the maximum unbalance signal, the following percent maximum unbalance signals shall be used:
Unbalance Signal
Nominal or Standard Tube Size, mm Magnitude, max %
Up to and incl 12 0.2
15 to 54, incl 0.3
Over 54 to 79, incl 0.4
10.1.3 Tubes that do not actuate the signalling device of the eddy-current testers shall be considered as conforming to the
requirements of this test. Tubes with discontinuities indicated by the testing unit shall, at the option of the manufacturer, be
reexamined or retested to determine whether the discontinuity is cause for rejection. Signals that are found to have been caused
by minor mechanical damage, soil, or moisture shall not be cause for rejection of the tubes provided the tube dimensions are still
within the prescribed limits and the tube is suitable for its intended application.
11. Dimensions, Mass, and Permissible Variations
11.1 For the purpose of determining conformance with the dimensional requirements prescribed in this specification, any
measured value outside the specified limiting values for any dimensions shall make the tube subject to rejection at the option of
the purchaser.
11.2 Nominal or Standard Dimensions, Wall Thickness, and Diameter Tolerances—The nominal or standard dimensions, wall
thickness, and diameter tolerances shall be in accordance with Table 1.
11.
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