MIL-S-7742D Screw Threads, Standard, Optimum Selected Series….pdf

INCH POUND
MIL-S-7742D
SUPERSEDNG
MIL-S-007742C
29 July 198
ML-S-7742B
2 February 1968
MILITARY SPECIFICATION
SCREW THREADS STANDARD, OPTMUM SELECTED SERIES
GENERAL SPECIFICATION FOR
Inactive for new design after 31 December 1991
For new design use MIL-S-8879
This specification is approved for use by all
Departments and Agencies of the Department of Defens
1. SCOPE
1.1 Purpose. This specification covers the requirements for a selected series of
standard Unified and Unified Miniature screw threads. classes 3A and 3B of
FED-STD-H28/2 and FED-STD-H28/5 for general aerospace and similar high-tech
application. The purpose of this specification is to
a. Relate verification requirements to the intended service application of the threaded
product
b. Provide default verification requirements if not otherwise specified
C. Allow the use of methods of verification found in FED-STD-H28/20 and ANS
ASME B1.3M
d. Encourage the use of new or more efficient methods of verification, such as on-line
or statistical process controls
Beneficial comments (recommendations, additions, deletions)and any
pertinent data which may be of use in improving this document should be
addressed to: ASD/ENES, Wright-patterson AFB OH 45433-6503 b
using the self-addressed Standardization Document Improvement Proposal
(D Form 1426)appearing at the end of this document or by letter
AMSC N/A
AREA THDS
DISTRIBUTION STATEMENT A. Approved for public release; distribution is
unlimited
MLL-S-7742D
1. 2 Application
1.2. 1 Reprocurements. This specification is to be used for reprocurement of threaded
Products used in designs released prior to the date of this specification.
1.2.2 New designs. For new designs the following applies
a. Use MIL-S-8879 for fatigue applications
b. Use FED-STD-H28/2 for general non-fatigue applications
c. Use FED-STD-H28/5 for thread sizes smaller than 0.060 inch
d. For class 2 threads, use the applicable section of FED-STD-H28
2. APPLCABLE DOCUMENIS
2.1 Government documents
2. 1. 1 Specification and standards. The following specification and standards form
a part of this specification to the extent specified herein. Uniess otherwise specified,
the issues of these documents shall be those listed in the issue of the Department of
Defense Index of Specifications and Standards (DODISS)and supplement thereto, cited
in the solicitation.(See 2.4.1)
SPECIFICATION
MILTTARY
MIL-S-8879
Screw Threads. Controlied Radius Root with Increased Minor
Diameter, General Specification for
STANDARDS
FEDEKAL
FPD-3-MO/
Nomenclature, Definitions, and Letter Symbols for Screw
I reads
FED-STD-H28/2
Unified Inch Screw Threads- UN and UNR Thread Forms
FED-STD-H28/5
Unified Miniature Screw Threads
FED-STD--28/6
Gages and Gaging for Unified Screw Threads
FED-STD-H28/20 Inspection Methods for Acceptability of UN, UNR, ONJ, M and
M Screw Threads