ASTM F1503-95

Standard Practice for Machine/Process Potential Study Procedure

SCOPE
1.1 This practice covers the proper method for establishing process potentials for new or existing processes.

General Information

• Status: Historical
• Publication Date: 31-Dec-1994
• ICS: 25.020 - Manufacturing forming processes
• Technical Committee: F16 - Fasteners
• Drafting Committee: F16.93 - Quality Assurance Provisions for Fasteners

Relations

• Replaced By: ASTM F1503-02 - Practice for Machine/Process Capability Study Procedure
• Effective Date: 10-Oct-2002

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or
withdrawn. Contact ASTM International (www.astm.org) for the latest information.
Designation: F 1503 – 95 An American National Standard
AMERICAN SOCIETY FOR TESTING AND MATERIALS
100 Barr Harbor Dr., West Conshohocken, PA 19428
Reprinted from the Annual Book of ASTM Standards. Copyright ASTM
Standard Practice for
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Machine/Process Potential Study Procedure
This standard is issued under the fixed designation F 1503; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope have primary responsibility for ensuring that the requirements
of this practice are met. The purchaser’s quality assurance
1.1 This practice covers the proper method for establishing
department shall be available to assist on an as-requested basis.
process potentials for new or existing processes.
4.3 New manufacturing processes will not be accepted for
2. Referenced Documents
use in production with Pp values less than 1.67. If a manufac-
turing process must be conditionally accepted, a process
2.1 ASTM Standards:
F 1469 Guide for Conducting a Repeatability and Repro- improvement/product control plan must be developed.
ducibility Study on Test Equipment for Nondestructive 4.3.1 The process improvement/product control plan shall
2
Testing
identify specific process improvement activities, which will be
2.2 ASME Standard: implemented to make the process fully capable as well as an
ASME-FAP-1 Quality Assurance Program Requirements interim inspection plan to ensure that nonconforming product
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for Fastener Manufacturers and Distributors
is not shipped to a customer.
4.4 Product Specifications:
3. Terminology
4.4.1 Prior to any process potential study, the product
3.1 Definitions of Terms Specific to This Standard:
specifications (nominal dimension and tolerances) must be
3.1.1 bilateral specifications—specifications that have both
identified, and an appropriate method of variables type inspec-
upper and lower values.
tion selected.
3.1.2 Pp—an index that indicates the variability of the
4.4.2 This practice is limited to bilateral specifications
process with respect to tolerance.
whose distributions can be expected to approximate a normal
3.1.3 Ppk—an index of process variability and centering.
curve. This practice should not be applied to unilateral speci-
This is a widely-used index which considers the process mean,
fications (flatness, concentricity, minimum tensile, maximum
range, and its relation to the specification nominal.
hardness, etc.).
3.1.4 process parameters—combination of people, equip-
4.5 Gage Capability Analysis:
ment, materials, methods, and environment that produce out-
4.5.1 All gaging systems used to evaluate product must
put.
have documentation for a gage repeatability and reproducibil-
3.1.5 unilateral specifications—specifications that have
ity study in accordance with Guide F 1469 before the process
only upper or lower values.
study is conducted.
3.1.6 s—an estimate of the standard deviation of a process
4.5.1.1 Gaging systems which consume #10 % of the
characteristic.
applicable product tolerance are considered acceptable.
4. Summary of Practices
4.5.1.2 Gaging systems which consume over 10 to 30 % of
the applicable product tolerance are generally considered to be
4.1 A process potential study is conducted to provide a level
unacceptable. However, users of this guide may authorize their
of confidence in the ability of a machine/process to meet
use depending on factors such as the criticality of the specifi-
engineering specification requirements. This is accomplished
cation in question, the cost of alternative gaging systems, and
through statistical process control techniques as defined in this
so forth.
practice.
4.2 For new equipment purchases, the purchaser’s manufac- 4.5.1.3 Gaging systems which consume more than 30 % of
the product tolerance are unacceptable and must be replaced.
turing engineering department, or equivalent discipline, shall
4.5.2 All gaging systems must be certified as accurate using
standards traceable to NIST.
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This practice is under the jurisdiction of ASTM Committee F-16 on Fasteners
4.6 Process Parameter Selection:
and is the direct responsibility of Subcommittee F16.93 on Quality Assurance
4.6.1 For studies conducted at the equipment vendor’s
Provisions for Fasteners.
Current edition approved Aug. 15, 1995. Published October 1995. Originally
facility, all process parameters (for example, infeed rates,
published as F 1503 – 94. Last previous edition F 1503 – 94.
coolant, dies, pressures, fixtures, etc.) must be established and
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Annual Book of ASTM Standards, Vol 15.08.
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documented prior to the process qualification test so the
Available from American Society of Mechanical Engine
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