ASTM F2257-22

Standard Specification for Wrought Seamless or Welded and Drawn 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Small Diameter Tubing for Surgical Implants (UNS S31673)

ABSTRACT
This specification covers the requirements for wrought seamless or welded and drawn 18chromium-14nickel-2.5molybdenum stainless steel small diameter tubing for surgical implants. Manufacturing method shall be seamless or welded and drawn process. Tubing shall conform to chemical composition, dimensions, and mechanical properties of this specification. Mechanical properties include ultimate tensile strength, yield strength, and elongation. Outside and inside diameter, wall thickness, length and straightness shall conform to the permissible limits of this specification.
SCOPE
1.1 This specification covers the requirements for wrought 18chromium-14nickel-2.5molybdenum stainless steel tubing used for the manufacture of surgical implants. Material shall conform to the applicable requirements of Specification F138 (for seamless) or Specification F139 (for welded and drawn). This specification addresses those product variables that differentiate small-diameter medical grade tubing from the bar, wire, sheet, and strip product forms covered in these specifications.  
1.2 This specification applies to cold finished straight length tubing with 3 mm [0.125 in.] and smaller nominal outside diameter (OD) and 0.5 mm [0.020 in.] and thinner nominal wall thickness.  
1.3 The specifications in 2.1 are referred to as the ASTM material standard(s) in this specification.  
1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Inch-pound units are shown in brackets. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other and values from the two systems shall not be combined.  
1.5 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.  
1.6 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: 30-Sep-2022
• ICS: 11.040.40 - Implants for surgery, prosthetics and orthotics
• Technical Committee: F04 - Medical and Surgical Materials and Devices
• Drafting Committee: F04.12 - Metallurgical Materials

Relations

• Refers: ASTM E8/E8M-24 - Standard Test Methods for Tension Testing of Metallic Materials
• Effective Date: 01-Jan-2024
• Refers: ASTM F138-19 - Standard Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Bar and Wire for Surgical Implants (UNS S31673)
• Effective Date: 01-Dec-2019
• Refers: ASTM F139-19 - Standard Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Sheet and Strip for Surgical Implants (UNS S31673)
• Effective Date: 01-Dec-2019
• Refers: ASTM A632-19 - Standard Specification for Seamless and Welded Austenitic Stainless Steel Tubing (Small-Diameter) for General Service
• Effective Date: 01-Sep-2019
• Refers: ASTM E8/E8M-16 - Standard Test Methods for Tension Testing of Metallic Materials
• Effective Date: 15-Jul-2016
• Refers: ASTM E8/E8M-15 - Standard Test Methods for Tension Testing of Metallic Materials
• Effective Date: 01-Feb-2015
• Refers: ASTM F2181-14 - Standard Specification for Wrought Seamless Stainless Steel Tubing for Surgical Implants
• Effective Date: 01-Oct-2014
• Refers: ASTM A632-04(2014) - Standard Specification for Seamless and Welded Austenitic Stainless Steel Tubing (Small-Diameter) for General Service
• Effective Date: 01-Oct-2014
• Refers: ASTM F138-13a - Standard Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Bar and Wire for Surgical Implants (UNS S31673)
• Effective Date: 01-Oct-2013
• Refers: ASTM E8/E8M-13 - Standard Test Methods for Tension Testing of Metallic Materials
• Effective Date: 01-Jun-2013
• Refers: ASTM F138-13 - Standard Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Bar and Wire for Surgical Implants (UNS S31673)
• Effective Date: 01-Apr-2013
• Refers: ASTM E112-12 - Standard Test Methods for Determining Average Grain Size
• Effective Date: 15-Nov-2012
• Refers: ASTM F139-12 - Standard Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Sheet and Strip for Surgical Implants (UNS S31673)
• Effective Date: 01-Oct-2012
• Refers: ASTM E8/E8M-11 - Standard Test Methods for Tension Testing of Metallic Materials
• Effective Date: 01-Dec-2011
• Refers: ASTM E112-10 - Standard Test Methods for Determining Average Grain Size
• Effective Date: 01-Nov-2010

Overview

ASTM F2257-22 is the international standard specification for wrought seamless or welded and drawn 18Chromium-14Nickel-2.5Molybdenum stainless steel small diameter tubing (UNS S31673) used primarily in surgical implants. Developed by ASTM International, this document defines the essential requirements for dimensional, mechanical, and surface properties of small-caliber stainless steel tubing intended for high-performance, biocompatible medical devices. Adherence to ASTM F2257-22 ensures tubing meets the quality and reliability demanded by surgeons and medical device manufacturers.

Key Topics

• Scope of Standard: Applies to cold finished, straight length tubing up to 3 mm (0.125 in.) nominal outside diameter and 0.5 mm (0.020 in.) or thinner wall thickness.
• Manufacturing Methods: Tubing can be manufactured through seamless or welded and drawn processes. Seamless tubing uses a continuous tube periphery. Welded and drawn tubing involves welding, drawing, and annealing, with weld bead and heat-affected zones virtually indistinguishable from the parent metal.
• Mechanical Requirements: Tubing must conform to specified values for ultimate tensile strength, yield strength, and elongation. The properties differ based on condition (annealed or cold worked) and wall thickness.
• Dimensional Tolerances: Strict limits are set for outside diameter (OD), inside diameter (ID), wall thickness, straightness, and concentricity to assure consistent product quality across batches.
• Surface Quality: Specifies requirements for cold-drawn, bright annealed, ground, or polished outer surfaces and clean, as-drawn or bright annealed inner finishes. Limits on maximum surface roughness and permissible imperfections are included.
• Chemical Composition: The tubing must fulfill the chemical composition requirements as defined in ASTM F138 (seamless) or ASTM F139 (welded and drawn).
• Certification & Quality Management: Manufacturers must provide certification of conformance and operate under recognized quality systems such as ISO 9001 or ISO 13485.
• Units of Measure: The standard supports both SI and inch-pound units but requires adherence to a single system per order.

Applications

ASTM F2257-22 tubing is essential for surgical implants and medical devices requiring high precision, strength, and biocompatibility. Key uses include:

• Coronary stents and other vascular implantable devices
• Orthopedic implants where small diameter tubular components are needed
• Fabrication of small-diameter medical instruments and guidewires
• Applications requiring superior corrosion resistance and mechanical strength within the human body

By meeting ASTM F2257-22, manufacturers ensure the tubing is appropriate for demanding medical environments and match global regulatory and clinical expectations for patient safety and device performance.

Related Standards

Several related and referenced standards provide further detail and application support:

• ASTM F138: Specification for Wrought 18Cr-14Ni-2.5Mo Stainless Steel Bar and Wire for Surgical Implants (UNS S31673) - basis for seamless tubing chemistry.
• ASTM F139: Specification for Wrought 18Cr-14Ni-2.5Mo Stainless Steel Sheet and Strip for Surgical Implants - basis for welded and drawn tubing chemistry.
• ASTM F2181: Wrought Seamless Stainless Steel Tubing for Surgical Implants - for other medical tubing forms.
• ASTM A632: Austenitic Stainless Steel Tubing (Small Diameter) for General Service.
• ISO 5832-1: Implants for Surgery - Metallic materials - Wrought stainless steel.
• ISO 13485 & ISO 9001: Quality management systems for regulatory and manufacturing environments.

These standards, alongside ASTM F2257-22, provide a framework for consistent, high-quality stainless steel medical tubing for global markets.

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Keywords: ASTM F2257-22, stainless steel tubing, surgical implants, medical device tubing, 18Chromium-14Nickel-2.5Molybdenum, UNS S31673, small diameter tubing, seamless tubing, welded and drawn tubing, ASTM standards, biocompatible tubing, quality management, ISO 13485.

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:F2257 −22
Standard Specification for
Wrought Seamless or Welded and Drawn 18Chromium-
14Nickel-2.5Molybdenum Stainless Steel Small Diameter
Tubing for Surgical Implants (UNS S31673)
This standard is issued under the fixed designation F2257; 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* Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
1.1 This specification covers the requirements for wrought
Barriers to Trade (TBT) Committee.
18chromium-14nickel-2.5molybdenum stainless steel tubing
used for the manufacture of surgical implants. Material shall
2. Referenced Documents
conform to the applicable requirements of Specification F138
2.1 ASTM Material Standards:
(for seamless) or Specification F139 (for welded and drawn).
F138Specification for Wrought 18Chromium-14Nickel-
This specification addresses those product variables that dif-
2.5MolybdenumStainlessSteelBarandWireforSurgical
ferentiate small-diameter medical grade tubing from the bar,
Implants (UNS S31673)
wire, sheet, and strip product forms covered in these specifi-
F139Specification for Wrought 18Chromium-14Nickel-
cations.
2.5Molybdenum Stainless Steel Sheet and Strip for Sur-
1.2 Thisspecificationappliestocoldfinishedstraightlength
gical Implants (UNS S31673)
tubing with 3 mm [0.125 in.] and smaller nominal outside
2.2 ASTM Standards:
diameter (OD) and 0.5 mm [0.020 in.] and thinner nominal
A632Specification for Seamless and Welded Austenitic
wall thickness.
Stainless Steel Tubing (Small-Diameter) for General Ser-
1.3 The specifications in 2.1 are referred to as the ASTM
vice
material standard(s) in this specification.
E8/E8MTest Methods for Tension Testing of Metallic Ma-
terials
1.4 The values stated in either SI units or inch-pound units
E29Practice for Using Significant Digits in Test Data to
are to be regarded separately as standard. Inch-pound units are
Determine Conformance with Specifications
shown in brackets. The values stated in each system are not
E112Test Methods for Determining Average Grain Size
necessarilyexactequivalents;therefore,toensureconformance
F2181Specification for Wrought Seamless Stainless Steel
with the standard, each system shall be used independently of
Tubing for Surgical Implants
the other and values from the two systems shall not be
IEEE/ASTM SI10American National Standard for Metric
combined.
Practice
1.5 This standard does not purport to address all of the
2.3 ISO Standards:
safety concerns, if any, associated with its use. It is the
ISO 5832-1Implants for Surgery—Metallic Materials Part
responsibility of the user of this standard to establish appro-
1: Wrought Stainless Steel
priate safety, health, and environmental practices and deter-
ISO 6892Metallic Materials—Tensile Testing
mine the applicability of regulatory limitations prior to use.
ISO9001Quality Management Systems—Requirements
1.6 This international standard was developed in accor-
ISO 13485 Medical Devices—Quality Management
dance with internationally recognized principles on standard-
Systems—Requirements for Regulatory Purposes
ization established in the Decision on Principles for the
1 2
This specification is under the jurisdiction of ASTM Committee F04 on For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Medical and Surgical Materials and Devices and is the direct responsibility of contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Subcommittee F04.12 on Metallurgical Materials. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved Oct. 1, 2022. Published October 2022. Originally the ASTM website.
approved in 2003. Last previous edition approved in 2014 as F2257–14. DOI: Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
10.1520/F2257-22. 4th Floor, New York, NY 10036, http://www.ansi.org.
*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
F2257−22
2.4 ASME Standards: 3.1.10 sample minimum wall thickness—the smallest indi-
ASMEY14.5.1MMathematical Definition of Dimensioning vidual wall thickness measurement taken around the circum-
and Tolerancing Principles ference on any one transverse cross section of a single sample
of tube.
3. Terminology
3.1.11 seamless tubing—tubing made by a process in which
3.1 Definitions of Terms Specific to This Standard: the tube periphery is continuous at all stages of the process.
3.1.1 individual wall thickness measurement—any one of
3.1.12 welded and drawn tubing—tubing fabricated from
the wall thickness measurements taken around the circumfer-
strip or sheet using welding, drawing, and annealing opera-
ence on any one transverse cross section of a single sample of
tions.
the tube.
4. General Requirements for Delivery
3.1.2 lot—the total number of product produced from the
4.1 In addition to the requirements of this specification, all
same melt heat under the same conditions at essentially the
applicable requirements of the appropriate ASTM material
same time.
standard shall apply.
3.1.3 lot average concentricity—the arithmetic average of
thesampleconcentricitiesmeasuredonastatisticallyrepresen- 4.2 In addition to the requirements of this specification, all
tative number of samples from the lot. applicable requirements of Specification A632 shall apply.
3.1.4 lot average wall thickness—the arithmetic average of
4.3 If a conflict exists between this specification and those
thesampleaveragewallthicknessesmeasuredonastatistically
listed in Section 2, or if a conflict exists between those
representative number of samples from the lot. specifications listed in 2.1 and those listed in 2.2 and 2.3, the
following order of precedence applies: (1) this specification,
3.1.5 nominal outside diameter (OD)—the outside diameter
(2) the ASTM material standard referenced on the purchase
specified on the purchaser’s order or engineering drawing
order, and (3) all other referenced specifications.
without regard to tolerance.
3.1.6 nominal wall thickness—the wall thickness specified 5. Ordering Information
onthepurchaser’sorderorengineeringdrawingwithoutregard
5.1 Inquiriesandordersformaterialunderthisspecification
to tolerance.
should include the following information:
3.1.7 sample average wall thickness—the arithmetic aver-
5.1.1 Quantity (weight, total length, or number of pieces),
ageofallindividualwallthicknessmeasurementsmeasuredon
5.1.2 This ASTM specification and date of issue,
a single sample.
5.1.3 The appropriate ASTM material standard (Specifica-
tion F138 for seamless or Specification F139 for welded and
3.1.8 sample concentricity—two times the offset between
drawn) and date of issue,
the centers of the two circles representing the outside diameter
5.1.4 Units to be certified—SI or inch-pound,
(OD) and the inside diameter (ID) of the tube.
5.1.5 Method of manufacture (see 6.1),
3.1.8.1 Discussion—For the purposes of this specification,
5.1.6 Condition (see Table 1),
the sample minimum wall and the sample maximum wall
5.1.7 Surface finish (see 6.3),
measured on any one transverse cross section of a single
5.1.8 Applicable dimensions—including OD and ID; OD
sample shall be used to calculate sample concentricity. The
and wall or ID and wall; length (exact, random, multiples); or
samplemaximumandsampleminimumwallthicknessshallbe
engineering drawing reference number,
the largest and smallest, respectively, of no less than four
5.1.9 Dimensional tolerances (see Table 2),
individual wall thickness measurements taken at uniformly
5.1.10 Special requirements or supplements, if any, and
spaced locations around the circumference of a single sample
5.1.11 Certification requirements.
of the tube. Sample concentricity shall be expressed as a
percent of the wall thickness and shall be calculated using the
6. Materials and Manufacture
following equation:
6.1 Method of Manufacture:
A 2 B
6.1.1 Tubing shall be made by the seamless or the welded
sampleconcentricitypercent 52 3 3100
S D
A1B
and drawn process.
where: 6.1.2 Seamless tubing shall be made by a seamless process
in which the tube periphery is continuous at all stages of the
A = sample maximum wall, and
process.
B = sample minimum wall.
6.1.3 Welded and drawn tubing shall be fabricated from
3.1.9 sample maximum wall thickness—the largest indi-
strip or sheet using welding, drawing, and annealing opera-
vidual wall thickness measurement taken around the circum-
tions. Welding shall be performed using a liquid phase weld
ference on any one transverse cross section of a single sample
process with no filler metal. Typical weld processes are
of tube.
tungsten inert gas (TIG) and laser. The drawing and annealing
operationsshallbeperformedinsuchawaythattheweldbead
and heat-affected zone are virtually indistinguishable micro-
Available from American Society of Mechanical Engineers (ASME), ASME
structurally and dimensionally from the parent metal when
International Headquarters, Three Park Ave., New York, NY 10016-5990, http://
www.asme.org. examined per 11.3.
F2257−22
TABLE 1 Mechanical Properties
A
Wall Thickness, Ultimate Tensile Strength, Yield Strength (0.2 % offset),
Elongation (% in 50 mm [2 in.] or 4D),
Condition
mm [in.] min MPa [psi] min MPa [psi] min (%)
Annealed 0.20 [0.008] to 0.46 [0.018] incl 490 [71 000] 190 [27 500] 40
0.05 [0.002] to 0.20 [0.008] excl 550 [80 000] 207 [30 000] 35
Less than 0.05 [0.002] 586 [85 000] 241 [35 000] 20
Cold worked 0.20 [0.008] to 0.46 [0.018] incl 860 [125 000] 690 [100 000] 10
0.05 [0.002] to 0.20 [0.008] excl 860 [125 000] 690 [100 000] 8
Less than 0.05 [0.002] 860 [125 000] 690 [100 000] 4
A
Elongation of material 1.6 mm [0.063 in.] or greater in diameter (D) shall be measured using a gauge length of 50 mm [2 in.] or 4D minimum. The gauge length shall
be reported with the test results. The method for determining elongation of material under 1.6 mm [0.063 in.] shall be agreed upon between purchaser and supplier.
Alternatively, a gauge length corresponding to ISO 6892 (5.65 times the square root of So, where So is the original cross-sectional area) may be used when agreed upon
between purchaser and supplier.
TABLE 2 Permissible Variation in OD and ID Dimensions
that the resultant wall thickness meets the minimum wall
Nominal OD or ID Permissible Variation thickness, and that the ground or polished surface meets the
A
mm [in.] from Nominal, mm [in.]
surface finish requirements of 6.3.1.
Less than 1.5 [0.060] ±0.013 [0.0005]
1.5 to 3.2 [0.060 to 0.125] incl. ±0.025 [0.001]
9.2 Inner surface imperfections shall not exceed 10% of
A
Unless otherwise specified, size tolerances are plus and minus as shown in the
wall thickness in depth.
table. When required by the purchaser, tolerances may be specified all plus and
nothingminus,orallminusandnothingplus,oranycombinationofplusandminus
9.3 The method of inspecting for these imperfections shall
if the total spread in size tolerance is not less than the total spread shown in the
table. be agreed upon between the purchaser and supplier.
10. Dimensions and Permissible Variation
6.2 Condition—Tubing shall be furnished, as specified, in
10.1 Units of Measure:
the annealed or cold worked condition as defined in Table 1.
10.1.1 Selection—This specification requires that the pur-
6.3 Surface Finish:
chaserselecttheunitsofmeasure(SIorinch-pound)tobeused
6.3.1 The tubing outer surface shall be furnished with a
for product certification. In the absence of a stated selection of
cold-drawn, bright annealed, ground, or polished finish. The
unitsonthepurchaseorder,thisselectionmaybeexpressedby
outer surface roughness shall be a maximum of 0.6µm
the purchaser in several alternate forms listed in order of
[25µin.] Ra.
precedence.
6.3.2 The tubing inner surface shall be furnished with an
10.1.1.1 If the purchaser and supplier have a history of
as-drawn finish or bright annealed finish. The inner surface
using specific units, these units shall continue to be certified
roughness shall be a maximum of 0.8 µm [30 µin.] Ra
until expressly changed by the purchaser.
maximum.
10.1.1.2 In the absence of historic precede
...

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: F2257 − 14 F2257 − 22
Standard Specification for
Wrought Seamless or Welded and Drawn 18 Chromium-
14Nickel-2.5Molybdenum 18Chromium-14Nickel-
2.5Molybdenum Stainless Steel Small Diameter Tubing for
Surgical Implants (UNS S31673)
This standard is issued under the fixed designation F2257; 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 covers the requirements for wrought 18chromium-14nickel-2.5molybdenum stainless steel tubing used for
the manufacture of surgical implants. Material shall conform to the applicable requirements of Specification F138 (for seamless)
or Specification F139 (for welded and drawn). This specification addresses those product variables that differentiate small-diameter
medical grade tubing from the bar, wire, sheet, and strip product forms covered in these specifications.
1.2 This specification applies to cold finished straight length tubing with 3 mm [0.125 in.] and smaller nominal outside diameter
(OD) and 0.5 mm [0.020 in.] and thinner nominal wall thickness.
1.3 The specifications in 2.1 are referred to as the ASTM material standard(s) in this specification.
1.4 The values stated in either inch-pound or SI units or inch-pound units are to be regarded separately as standard. Inch-pound
units are shown in parentheses.brackets. The values stated in each system mayare not benecessarily exact equivalents; therefore,
to ensure conformance with the standard, each system shall be used independently of the other. Combiningother and values from
the two systems may result in non-conformance with the standard.shall not be combined.
1.5 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.
1.6 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 Material Standards:
F138 Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Bar and Wire for Surgical Implants
(UNS S31673)
This specification is under the jurisdiction of ASTM Committee F04 on Medical and Surgical Materials and Devices and is the direct responsibility of Subcommittee
F04.12 on Metallurgical Materials.
Current edition approved Nov. 1, 2014Oct. 1, 2022. Published February 2015October 2022. Originally approved in 2003. Last previous edition approved in 20092014 as
F2257 – 09.F2257 – 14. DOI: 10.1520/F2257-14.10.1520/F2257-22.
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.
*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
F2257 − 22
F139 Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Sheet and Strip for Surgical Implants
(UNS S31673)
2.2 ASTM Standards:
A632 Specification for Seamless and Welded Austenitic Stainless Steel Tubing (Small-Diameter) for General Service
E8/E8M Test Methods for Tension Testing of Metallic Materials
E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
E112 Test Methods for Determining Average Grain Size
F2181 Specification for Wrought Seamless Stainless Steel Tubing for Surgical Implants
IEEE/ASTM SI 10 American National Standard for Use of the International System of Units (SI): The Modern Metric
SystemMetric Practice
2.3 ISO Standards:
ISO 5832-1 Implants for Surgery—Metallic Materials Part 1: Wrought Stainless Steel
ISO 6892 Metallic Materials — Tensile Materials—Tensile Testing
ISO 9001 Quality Management Systems — RequirementsSystems—Requirements
ISO 13485 Medical devices — Quality management systems — Requirements for regulatory purposesDevices—Quality
Management Systems—Requirements for Regulatory Purposes
2.4 ASME Standards:
ASME Y14.5.1M Mathematical Definition of Dimensioning and Tolerancing Principles
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
3.1.1 individual wall thickness measurement—any one of the wall thickness measurements taken around the circumference on any
one transverse cross section of a single sample of the tube.
3.1.2 lot—the total number of product produced from the same melt heat under the same conditions at essentially the same time.
3.1.3 lot average concentricity—the arithmetic average of the sample concentricities measured on a statistically representative
number of samples from the lot.
3.1.4 lot average wall thickness—the arithmetic average of the sample average wall thicknesses measured on a statistically
representative number of samples from the lot.
3.1.5 nominal outside diameter (OD)—the outside diameter specified on the purchaser’s order or engineering drawing without
regard to tolerance.
3.1.6 nominal wall thickness—the wall thickness specified on the purchaser’s order or engineering drawing without regard to
tolerance.
3.1.7 sample average wall thickness—the arithmetic average of all individual wall thickness measurements measured on a single
sample.
3.1.8 sample concentricity—two times the offset between the centers of the two circles representing the outside diameter (OD) and
the inside diameter (ID) of the tube.
3.1.8.1 Discussion—
For the purposes of this specification, the sample minimum wall and the sample maximum wall measured on any one transverse
cross section of a single sample shall be used to calculate sample concentricity. The sample maximum,maximum and sample
minimum wall thickness shall be the largest and smallest respectivelysmallest, respectively, of no less than four individual wall
thickness measurements taken at uniformly spaced locations around the circumference of a single sample of the tube. Sample
concentricity shall be expressed as a percent of the wall thickness and shall be calculated using the following equation:
A 2 B
sample concentricity percent 5 23 3100
S D
A1B
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
Available from American Society of Mechanical Engineers (ASME), ASME International Headquarters, Three Park Ave., New York, NY 10016-5990, http://
www.asme.org.
F2257 − 22
A 2 B
sample concentricity percent 5 23 3100
S D
A1B
where:
where:
A = sample maximum wall, and
B = sample minimum wall.
3.1.9 sample maximum wall thickness—the largest individual wall thickness measurement taken around the circumference on any
one transverse cross section of a single sample of tube.
3.1.10 sample minimum wall thickness—the smallest individual wall thickness measurement taken around the circumference on
any one transverse cross section of a single sample of tube.
3.1.11 seamless tubing—tubing made by a process in which the tube periphery is continuous at all stages of the process.
3.1.12 welded and drawn tubing—tubing fabricated from strip or sheet using welding, drawing, and annealing operations.
4. General Requirements for Delivery
4.1 In addition to the requirements of this specification, all applicable requirements of the appropriate ASTM material standard
shall apply.
4.2 In addition to the requirements of this specification, all applicable requirements of Specification A632 shall apply.
4.3 If a conflict exists between this specification and those listed in Section 2, or if a conflict exists between those specifications
listed in 2.1 and those listed in 2.2 and 2.3, the following order of precedence applies: (1) this specification, (2) the ASTM material
standard referenced on the purchase order, and (3) all other referenced specifications.
5. Ordering Information
5.1 Inquiries and orders for material under this specification should include the following information:
5.1.1 Quantity (weight, total length, or number of pieces),
5.1.2 This ASTM specification and date of issue,
5.1.3 The appropriate ASTM material standard (Specification F138 for seamless or Specification F139 for welded and drawn) and
date of issue,
5.1.4 Units to be certified—SI or inch-pound.inch-pound,
5.1.5 Method of Manufacturemanufacture (see 6.1),
5.1.6 Condition (see Table 1),
5.1.7 Surface Finishfinish (see 6.3),
5.1.8 Applicable Dimensions—includingdimensions—including OD and ID; OD and wall or ID and wall; length (exact, random,
multiples); or engineering drawing reference number,
5.1.9 Dimensional Tolerancestolerances (see Table 2),
5.1.10 Special requirements or supplements, if any, and
5.1.11 Certification requirements.
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TABLE 1 Mechanical Properties
A
Wall Thickness, Ultimate Tensile Strength, Yield Strength (0.2 % offset),
Elongation (% in 50 mm [2 in.] or 4D),
Condition
mm [in.] min MPa [psi] min MPa [psi] min (%)
Annealed 0.20 [0.008] to 0.46 [0.018] incl 490 [71 000] 190 [27 500] 40
0.05 [0.002] to 0.20 [0.008] excl 550 [80 000] 207 [30 000] 35
Less than 0.05 [0.002] 586 [85 000] 241 [35 000] 20
Cold worked 0.20 [0.008] to 0.46 [0.018] incl 860 [125 000] 690 [100 000] 10
0.05 [0.002] to 0.20 [0.008] excl 860 [125 000] 690 [100 000] 8
Less than 0.05 [0.002] 860 [125 000] 690 [100 000] 4
A
Elongation of material 1.6 mm [0.063 in.] or greater in diameter (D) shall be measured using a gagegauge length of 50 mm [2 in.] or 4D. 4D minimum. The gagegauge
length shall be reported with the test results. The method for determining elongation of material under 1.6 mm [0.063 in.] shall be agreed upon between purchaser and
supplier. Alternatively, a gauge length corresponding to ISO 6892 (5.65 times the square root of So, where So is the original cross sectional cross-sectional area) may be
used when agreed upon between purchaser and supplier.
TABLE 2 Permissible Variation in OD and ID Dimensions
Nominal OD or ID Permissible Variation
A
mm [in.] from Nominal, mm [in.]
Less than 1.5 [0.060] ±0.013 [0.0005]
1.5 to 3.2 [0.060 to 0.125] incl. ±0.025 [0.001]
A
Unless otherwise specified, size tolerances are plus and minus as shown in the
table. When required by the purchaser, tolerances may be specified all plus and
nothing minus, or all minus and nothing plus, or any combination of plus and minus
if the total spread in size tolerance is not less than the total spread shown in the
table.
6. Materials and Manufacture
6.1 Method of Manufacture:
6.1.1 Tubing shall be made by the seamless or the welded and drawn process.
6.1.2 Seamless tubing shall be made by a seamless process in which the tube periphery is continuous at all stages of the process.
6.1.3 Welded and drawn tubing shall be fabricated from strip or sheet using welding, drawing, and annealing operations. Welding
shall be performed using a liquid phase weld process with no filler metal. Typical weld processes are tungsten inert gas (TIG) and
laser. The drawing and annealing operations shall be performed in such a way that the weld bead and heat affected heat-affected
zone are virtually indistinguishable microstructurally and dimensionally from the parent metal when examined per 11.3.
6.2 Condition—Tubing shall be furnished, as specified, in the annealed or cold worked condition as defined in Table 1.
6.3 Surface Finish:
6.3.1 The tubing outer surface shall be furnished with a cold-drawn, bright annealed, ground, or polished finish. The outer surface
roughness shall be a maximum of 0.6 μm [25 μin.] 0.6 μm [25 μin.] Ra.
6.3.2 The tubing inner surface shall be furnished with an as-drawn finish or bright annealed finish. The inner surface roughness
shall be a maximum of 0.8 μm [30 μin.] Ra maximum.
6.3.3 The method used to determine surface roughness shall be agreed upon between purchaser and supplier.
7. Chemical Composition
7.1 For seamless tubing, the heat analysis limits and product analysis tolerances of Specification F138 shall apply. For welded and
drawn tubing, the heat analysis limits and product analysis tolerances of Specification F139 shall apply.
F2257 − 22
8. Mechanical Properties
8.1 Material shall meet the appropriate mechanical properties specified in Table 1, when tested in accordance with Test Method
E8/E8M. Mechanical properties for material in conditions other than those in Table 1 shall be agreed upon between purchaser and
supplier.
8.2 If both tensile properties and hardness are specified on the purchase order, tensile properties shall be used to accept or reject.
Hardness shall be reported for information only.
9. Permissible Outer and Inner Surface Imperfections
9.1 Outer surface imperfection shall not exceed 10 % of wall thickness in depth. Outer surface imperfections may be remo
...