ASTM D7211-23

Standard Specification for Parts Machined from Polychlorotrifluoroethylene (PCTFE) and Intended for General Use

ABSTRACT
This specification establishes the requirements for finished parts machined from unplasticized polychlorotrifluoroethylene (PCTFE) homopolymers containing regrind and recycled polymer intended for general commercial use. This specification does not cover parts machined from PCTFE copolymers, PCTFE films or tapes, or modified PCTFE containing pigments or plasticizers. Nor does it cover PCTFE parts used in aerospace applications involving storage and handling of oxygen media, air media, inert media, and certain reactive media (specifically ammonia, gaseous hydrogen, and liquid hydrogen), wherein dimensional stability, high molecular weight, molecular weight retention, and crystallinity control are important considerations. Materials shall be tested on and conform accordingly to the following properties: specific gravity; melting point; deformation under load; zero strength time (ZST); annealing performance; and dimensional stability.
SCOPE
1.1 This specification is intended to be a means of calling out finished machined parts ready for general use.  
1.2 This specification establishes requirements for parts machined from polychlorotrifluoroethylene (PCTFE) semifinished parts.  
1.3 For aerospace grade, machined PCTFE parts, use Specification D7194.
Note 1: Quick-quenched PCTFE will potentially exhibit dimensional relaxation in the vicinity of Tg = 55°C (131°F).
Note 2: Although no recommendations are made regarding the limiting upper use temperature of PCTFE, the heat deflection temperature of PCTFE as determined by Test Method D648 is 126°C (259°F).  
1.4 The values stated in SI units are to be regarded as standard. The values in parentheses are for information only.  
1.5 The following precautionary caveat pertains only to the test methods portion, Section 11, 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.
Note 3: There is no known ISO equivalent to 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: 30-Apr-2023
• ICS: 83.140.01 - Rubber and plastics products in general
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.15 - Thermoplastic Materials

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: D7211 − 23
Standard Specification for
Parts Machined from Polychlorotrifluoroethylene (PCTFE)
1
and Intended for General Use
This standard is issued under the fixed designation D7211; 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* 2. Referenced Documents
2
2.1 ASTM Standards:
1.1 This specification is intended to be a means of calling
out finished machined parts ready for general use. D618 Practice for Conditioning Plastics for Testing
D648 Test Method for Deflection Temperature of Plastics
1.2 This specification establishes requirements for parts
Under Flexural Load in the Edgewise Position
machined from polychlorotrifluoroethylene (PCTFE) semifin-
D792 Test Methods for Density and Specific Gravity (Rela-
ished parts.
tive Density) of Plastics by Displacement
1.3 For aerospace grade, machined PCTFE parts, use Speci-
D883 Terminology Relating to Plastics
fication D7194.
D1430 Classification System for Polychlorotrifluoroethylene
(PCTFE) Plastics
NOTE 1—Quick-quenched PCTFE will potentially exhibit dimensional
D1600 Terminology for Abbreviated Terms Relating to Plas-
relaxation in the vicinity of T = 55°C (131°F).
g
NOTE 2—Although no recommendations are made regarding the limit- tics
ing upper use temperature of PCTFE, the heat deflection temperature of
D2117 Test Methods for Carbon Black—Surface Area by
PCTFE as determined by Test Method D648 is 126°C (259°F). 3
Nitrogen Adsorption (Withdrawn 1999)
1.4 The values stated in SI units are to be regarded as
D4591 Test Method for Determining Temperatures and
standard. The values in parentheses are for information only. Heats of Transitions of Fluoropolymers by Differential
Scanning Calorimetry
1.5 The following precautionary caveat pertains only to the
D7194 Specification for Aerospace Parts Machined from
test methods portion, Section 11, of this specification: This
Polychlorotrifluoroethylene (PCTFE)
standard does not purport to address all of the safety concerns,
if any, associated with its use. It is the responsibility of the user
3. Terminology
of this standard to establish appropriate safety, health, and
environmental practices and determine the applicability of 3.1 Definitions:
regulatory limitations prior to use. 3.1.1 Terms are defined in accordance with Terminologies
D883 and D1600 unless listed below.
NOTE 3—There is no known ISO equivalent to this standard.
3.1.2 Zero Strength Time (ZST), n—time measured in accor-
1.6 This international standard was developed in accor-
dance with Section 10 of Classification D1430 to check the
dance with internationally recognized principles on standard-
relative molecular weight of the PCTFE material.
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
4. Classification
mendations issued by the World Trade Organization Technical
4.1 Part shape and size shall be defined by the applicable
Barriers to Trade (TBT) Committee.
purchase order.
1 2
This specification is under the jurisdiction of ASTM Committee D20 on For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Plastics and is the direct responsibility of Subcommittee D20.15 on Thermoplastic contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Materials. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved May 1, 2023. Published May 2023. Originally the ASTM website.
3
approved in 2005. Last previous edition approved in 2018 as D7211 - 13(2018). The last approved version of this historical standard is referenced on
DOI: 10.1520/D7211-23. www.astm.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
1

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D7211 − 23
4.2 General purpose grade PCTFE shall be Class 1 homopo- 8.4 The melting point of finished parts shall be determined
lymer in accordance Classification D1430. to be in the range of 210 to 220°C (410 to 428°F) as
determined in 11.2.
4.3 The grade of product shall be categorized in accordance
with Classification D1430 as follows: 8.5 Finished parts shall be made from semifinished articles
4.3.1 Grade 0 having an undetermined or unspecified ZST. having an as-molded zero strength time (ZST ) of 300 to
stock
4.3.2 Grade 1 having an as-polymerized ZST of 100 to 19
...

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: D7211 − 13 (Reapproved 2018) D7211 − 23
Standard Specification for
Parts Machined from Polychlorotrifluoroethylene (PCTFE)
1
and Intended for General Use
This standard is issued under the fixed designation D7211; 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 Scope*
1.1 This specification is intended to be a means of calling out finished machined parts ready for commercialgeneral use.
1.2 This specification establishes requirements for parts machined from unplasticized, 100 % polychlorotrifluoroethylene
(PCTFE) homopolymers.semifinished parts.
1.3 This specification does not cover parts machined from PCTFE copolymers, PCTFE film or tape less than 0.25-mm (0.010-in.)
thick, or modified PCTFE (containing pigments or plasticizers).
1.4 This specification allows for parts containing regrind and recycled material.
1.5 The specification does not cover PCTFE parts used in aerospace applications involving storage and handling of oxygen media,
air media, inert media, and certain reactive media (specifically ammonia, gaseous hydrogen, and liquid hydrogen), in which
dimensional stability, high molecular weight, molecular weight retention, and crystallinity control are important considerations.
For aerospace grade, machined PCTFE parts, use Specification D7194.
1.3 Application—PCTFE parts covered byFor aerospace grade, machined PCTFE parts, use Specification D7194this specification
are made of 100 % PCTFE resin, free of plasticizers, fillers, or other additives. The parts meet specific physical characteristics
appropriate for their end use, and are typically used in applications requiring good electrical properties or resistance to aggressive
chemical media. General purpose PCTFE parts include seals, gaskets, valve and pump parts (cryogenic and noncryogenic),
translucent tubing, sight glasses, flowmeter tubes, heavy-walled solid pipes and fittings, gears, cams, bearings, laboratory ware,
circuit boards, electrical connector covers and switches, radome covers, and a variety of other stock shapes. They are removed and
replaced during normal maintenance procedures. The parts also experience static or dynamic mechanical loading, and temperatures
ranging from cryogenic to temperatures at or above the glass transition temperature, .T = 55°C (131°F).
g
NOTE 1—Quick-quenched PCTFE will potentially exhibit dimensional relaxation in the vicinity of T . = 55°C (131°F).
g
NOTE 2—Although no recommendations are made regarding the limiting upper use temperature of PCTFE, the heat deflection temperature of PCTFE as
determined by Test Method D648 is 126°C (259°F).
1.4 The values stated in SI units are to be regarded as standard. The values in parentheses are for information only.
1
This specification is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.15 on Thermoplastic Materials.
Current edition approved Nov. 1, 2018May 1, 2023. Published November 2018May 2023. Originally approved in 2005. Last previous edition approved in 20132018 as
D7211 - 13.D7211 - 13(2018). DOI: 10.1520/D7211-13R18.10.1520/D7211-23.
*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
1

---------------------- Page: 1 ----------------------
D7211 − 23
1.5 The following precautionary caveat pertains only to the test methods portion, Section 11, 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.
NOTE 3—There is no known ISO equivalent to 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
2.1 ASTM Standards:
D618 Practice for Conditioning Plastics for Testing
D648 Test Method for Deflection Temperature of Plastics Under
...