ASME CA-1:2014 pdf free download.Metric 12-Point Flange Head Screws.
ASME CA-1 covers the complete dimensional and general data for coarse thread metric series 12-point flange screws recognized as American National Standard. The inclusion of dimensional data in this Standard is not intended to imply that all products deseribed are stock production items.
2 COMPARISONS WITH ISO STANDARDS
Letter symls designating dimensional characteristics are in accord with ISO 225, except where capital letters instead of lowercase letters have been used in the ISO standards.
3 REFERENCED STANDARDS
The following isa list of publications referenced in this Standard. Unless otherwise specified, the standard(s) referenced shall be the most recently issued at the time of order placement.
ASME B1.3M, Screw Thread Gaging Systems for Dimensional Acceptability â Inch and Metric Threads (UN, UNR, UNJ, M, and MJ)
ASME Bl.13M, Metric Screw Threads â M Profile ASME B18.2.8, Clearance Holes for Bolts, Screws, and Studs
ASME 1118.2.9, Straightness Gage and Gaging for Bolts and Screws
ASME B18.12, Glossary of Terms for Mechanical Fasteners
ASME B18.18, Quality Assurance for Fasteners ASME 1118.24, Part Identifying Number (lâlN) Code System Standard for 1118 Externally Threaded Fasteners
ASME Y145, Dimensioning and Tolerancing Publisher: The American Society of Mechanical Engineers (ASME), Two Park Avenue, New York, NY 10016-5990; Order Department: 22 Law Drive, Box 2900, Fairfield, NJ 070O7-29() (www.asme.org)
ASTM F468M Standard Specification for Nonferrous Bolts, Hex Cap Screws, and Studs for General Use
ASTM F788/F788M, Standard Specification for Surface Discontinuities of Bolts, Screws and Studs, Inch and Metric Series
20 MATERIALS AND MECHANICAL PROPERTIES
20.1 Steel
Unless otherwise specified, steel screws shall conform to the requirements of ISO 898.1, Property Class 12.9.
20.2 Corrosion-Resistant Steels
Unless otherwise specified, corrosion-resistant steel screws shall conform to the requirements of ISO 3506-1 for the specified property class.
20.3 Nonferrous Metals
Unless otherwise specified, nonferrous screws shall conform to the requirements of ASTM F46HM or the specified property alloy.
21 IDENTIFICATION SYMBOLS
Markings shall be raised or recessed on the top of the head or raised on the top of the flange unless otherwise specified by the purchaser. Markings shall be legible to the unaided eye with the exception of corrective lenses. When raised, markings shall project not less than 0.1 mm for Mid and smaller screws, and 0.3 mm for NI 16 screws, above the top surface of the head or flange; and total head height (head plus markings) shall not exceed the specified maximum head height. K maximum, plus 0.1 mm for M5 and M6 screws, 0.2 mm for MS and Ml0 screws, 0.3 mm for Mi2 and Mi4 screws, and 0.4 mm for M16 screws.
21.1 Property Class Symbols
Each screw shall be marked in accordance with the requirements of the applicable specification for its material and mechanical properties.
21.2 source Symbols
Each screw shall be marked to identify its source(manufacturer or private label distributor).
22 FINISH
Unless otherwise specified, screws shall be furnishedwith one of the following “standard surfaces as manu-factured,” at the option of the manufacturer:
(a) bright uncoated
(b)thermal black oxide(c) chemical black oxide
Hydrogen embrittlement tests shall not be requiredfor screws furnished in these conditions.
For other protective finishes specified with an applica-ble finish specification, precautions to minimize embrit-tlement shall be exercised.
23WORKMANSHIP
Screws shall be free from surface imperfections suchas burrs, seams, laps, loose scale, and other surface irreg-ularities that could affect serviceability.
24INSPECTION AND QUALITY ASSURANCE
Unless otherwise specified,acceptability ofscrews shall be determined in accordance withASME B18.18.
25CLEARANCE HOLES
The recommended sizes of clearance holes in materialto be assembled using 12-point flange screws are thenormal series given in ASME B18.2.8.
