ASTM F788/F788M-06

Standard Specification for Surface Discontinuities of Bolts, Screws, and Studs, Inch and Metric Series

SCOPE
1.1 This specification establishes allowable limits for the various types of surface discontinuities that may occur during the manufacture and processing of bolts, screws, and studs, including heat-treated machine screws, tapping screws, and sems (the washers of screw-washer assemblies are excluded). This specification covers metric series products with nominal diameters of 4 mm and larger and with specified minimum tensile strengths of 420 MPa and higher; and inch series products with nominal diameters of No. 5 (0.1250 in.) and larger and with specified minimum tensile strengths of 60 000 psi and higher.
1.2 When the engineering requirements of the application necessitate control of surface discontinuities on bolts, screws, or studs, the purchaser shall specify conformance to ASTM Specification F 788/F 788M, in the original inquiry and purchase order.
1.2.1 When the engineering requirements of the application necessitate that surface discontinuities on bolts, screws, and studs be controlled within limits closer than those specified in this specification, the purchaser shall specify the applicable limits in the original inquiry and purchase order.
1.3 The allowable limits established in this specification for metric bolts, screws, and studs with nominal diameters from 4 to 24 mm inclusive, are essentially identical with requirements given in ISO 6157/I. There are no ISO standards for surface discontinuities on any inch-series products.
1.4 The values stated in either SI (metric) or inch-pound units are to be regarded separately as standard. The values stated in each system are not exact equivalents, therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.

General Information

• Status: Historical
• Publication Date: 31-May-2006
• ICS: 21.060.10 - Bolts, screws, studs
• Technical Committee: F16 - Fasteners
• Drafting Committee: F16.93 - Quality Assurance Provisions for Fasteners

Relations

• Replaces: ASTM F788/F788M-05 - Standard Specification for Surface Discontinuities of Bolts, Screws, and Studs, Inch and Metric Series
• Effective Date: 01-Jun-2006
• Replaced By: ASTM F788/F788M-07 - Standard Specification for Surface Discontinuities of Bolts, Screws, and Studs, Inch and Metric Series
• Effective Date: 15-Nov-2007
• Referred By: ASTM A394-08(2015) - Standard Specification for Steel Transmission Tower Bolts, Zinc-Coated and Bare
• Effective Date: 01-Jun-2006
• Referred By: ASTM F3329-18 - Standard Specification for Carbon and Alloy Steel Metric Rivets
• Effective Date: 01-Jun-2006
• Referred By: ASTM F837-20 - Standard Specification for Stainless Steel Socket Head Cap Screws
• Effective Date: 01-Jun-2006
• Referred By: ASTM A354-17e2 - Standard Specification for Quenched and Tempered Alloy Steel Bolts, Studs, and Other Externally Threaded Fasteners
• Effective Date: 01-Jun-2006
• Referred By: ASTM F3042-13(2018) - Standard Specification for Nonferrous Hex Socket, Slotted Headless, and Square Head Set Screws
• Effective Date: 01-Jun-2006
• Referred By: ASTM F1470-19 - Standard Practice for Fastener Sampling for Specified Mechanical Properties and Performance Inspection
• Effective Date: 01-Jun-2006
• Referred By: ASTM F880-12(2017) - Standard Specification for Stainless Steel Socket, Square Head, and Slotted Headless-Set Screws
• Effective Date: 01-Jun-2006
• Referred By: ASTM A449-14(2020) - Standard Specification for Hex Cap Screws, Bolts and Studs, Steel, Heat Treated, 120/105/90 ksi Minimum Tensile Strength, General Use
• Effective Date: 01-Jun-2006
• Referred By: ASTM F2882/F2882M-17 - Standard Specification for Screws, Alloy Steel, Heat Treated, 170 ksi and 1170 MPa Minimum Tensile Strength (Inch and Metric)
• Effective Date: 01-Jun-2006
• Referred By: ASTM F2281-04(2017) - Standard Specification for Stainless Steel and Nickel Alloy Bolts, Hex Cap Screws, and Studs, for Heat Resistance and High Temperature Applications
• Effective Date: 01-Jun-2006

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 788/F 788M – 06
Standard Specification for
Surface Discontinuities of Bolts, Screws, and Studs, Inch
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and Metric Series
This standard is issued under the fixed designation F 788/F 788M; 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.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope* 2. Referenced Documents
2
1.1 This specification establishes allowable limits for the 2.1 ASTM Standards:
various types of surface discontinuities that may occur during E 340 Test Method for Macroetching Metals and Alloys
the manufacture and processing of bolts, screws, and studs, F 1470 GuideforFastenerSamplingforSpecifiedMechani-
including heat-treated machine screws, tapping screws, and cal Properties and Performance Inspection
sems (the washers of screw-washer assemblies are excluded). F 1789 Terminology for F16 Mechanical Fasteners
3
This specification covers metric series products with nominal 2.2 ISO Standard:
diameters of 4 mm and larger and with specified minimum ISO 6157/I Fasteners, Surface Discontinuities on Bolts,
tensile strengths of 420 MPa and higher; and inch series Screws and Studs
products with nominal diameters of No. 5 (0.1250 in.) and
3. Ordering Information
larger and with specified minimum tensile strengths of 60 000
psi and higher. 3.1 Orders for bolts, screws, and studs requiring disconti-
nuity control shall include the following:
1.2 When the engineering requirements of the application
necessitate control of surface discontinuities on bolts, screws, 3.1.1 ASTM designation and date of issue of this specifica-
tion.
or studs, the purchaser shall specify conformance to ASTM
Specification F 788/F 788M, in the original inquiry and pur- 3.1.2 Special requirements, for example, closer discontinu-
ity limits (1.2.1) and inspection sampling plan (6.2).
chase order.
1.2.1 When the engineering requirements of the application
4. Types of Surface Discontinuities (see Terminology
necessitate that surface discontinuities on bolts, screws, and
F 1789 for definitions not provided)
studs be controlled within limits closer than those specified in
4.1 Crack
this specification, the purchaser shall specify the applicable
4.1.1 Quench Cracks—Typical quench cracks are shown in
limits in the original inquiry and purchase order.
Fig. 1. Limits are specified in 5.2.
1.3 The allowable limits established in this specification for
4.1.2 Forging Cracks—Typical forging cracks are shown in
metric bolts, screws, and studs with nominal diameters from 4
Fig. 2. Limits are specified in 5.3.
to 24 mm inclusive, are essentially identical with requirements
4.2 Burst—Typical bursts are shown in Fig. 3. Limits are
given in ISO 6157/I. There are no ISO standards for surface
specified in 5.4.
discontinuities on any inch-series products.
4.2.1 Shear Burst—A shear burst is an open break in the
1.4 The values stated in either SI (metric) or inch-pound
metal located at approximately a 45° angle to the product axis.
units are to be regarded separately as standard. The values
Shear bursts occur most frequently at the periphery of products
stated in each system are not exact equivalents, therefore, each
having flanged or circular heads. Shear bursts may also occur
system must be used independently of the other. Combining
on the sides of hex-head products. Typical shear bursts are
values from the two systems may result in nonconformance
shown in Fig. 3. Limits are specified in 5.4.
with the specification.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
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This specification is under the jurisdiction of ASTM Committee F16 on contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Fasteners and is the direct responsibility of Subcommittee F16.93 on Quality Standards volume information, refer to the standard’s Document Summary page on
Assurance Provisions for Fasteners. the ASTM website.
3
Current edition approved June 1, 2006. Published June 2006. Originally Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
approved in 1982. Last previous edition approved in 2005 as F 788/F 788M – 05. 4th Floor, New York, NY 10036.
*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.
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F 788/F 788M – 06
FIG. 1 Typical Quench Cracks
mum) or head diameter (specified maximum) of circular head
products. For metric series products, D and Dc are in millime-
tres; for inch-seri
...