ASME B18.31.2-2014 pdf – Continuous Thread Stud, Double-End Stud, and Flange Bolting Stud (StudBolt) (inch Series).
11.2 Materials for Flange Bolting Studs (Stud Bolts)
Flange bolting studs may be supplied to any grade covered by the following ASTM material standards:
A 193/Al 93M, A320/ A320M, A437/ A437M, A453/ A453M, A540/A540M, or Al014/A1OI4M.
12 IDENTIFICATION SYMBOLS
Markings shall be located on either the ends or the bodies of the studs unless otherwise specified.
12.1 Property Class Symbol
Each stud shall be marked in accordance with the requirements of the applicable specification (see section II) for its chemical and mechanical requirements. For tap-end studs, the material property class symbol shall he marked on the nut end or the body.
12.2 Source Symbols
Each stud of a size requiring marking, based on its specified material standard, shall be marked to identify its source (manufacturer or private label distributor).
13 FINISH
Unless otherwise specfied, studs other than corrosion—resistant stainless steels shall he supplied with a natural (as-processed) finish, uriplated or urwoated, in a clean condition, and lightly oiled. Studs produced froni corrosion-resistant stainless steels shall be passivated in accordance with ASTM A380.
Platings and coatings are not recommended for interference-fft studs.
Requirements for zinc plating are contained in ASTM F1941.
14 WORKMANSHIP
Unless otherwise specified, studs shall he free from surface imperfections such as burrs, seams, laps, loose scale, or other irregularities that could affect serviceability. Surface discontrnuities shall comply with the requirements of ASTM F788/F788M.
15 STRAIGHTNESS
Straightness shall conform to the requirements of ASME B18.2.9.
16 INSPECTION AND QUALITY ASSURANCE
Studs shall he inspected to determine conformance with this Standard. Inspection procedures may he specified by the purchaser on the inquiry, purchase order, or the engineering drawings, or shall he as agreed upon between the purchaser and supplier prior to acceptance of the order. In the absence of a defined agreement, the requirenwnts of ASME B18J8 shall apply.
17 CLEARANCE HOLES
The recommended sizes of clearance holes in material to be assembled using inch studs are those listed in ASME B18.2.8 for inch fasteners.
18 STUD DESIGNATION
(a) Description: Studs shall be designated by the following data, preferably in the sequence shown:
(1) product name
(2) product standard (ASME B18.3l.2)
(3) nominal diameter and thread pitch for Class 2A screw threads
(4) nominal diameter, thread pitch, and major diameter thread suffix from ASME Bl.12 (including Appendices B and C) for NC—5 interference threads, when specified
(5) nominal length
(6) material (applicable standard and grade or alloy)
(7) coatmg, if required
For tap-end studs, show tap-end thread type from ASME BL12, length, and nut-end thread, as shown in Example (3) beloW.
EXAMPLES:
(1) Continuous thread stud, ASME B18.31.2, -13 x 4, SAE J429 Grade 5, zinc plated per ASTM F1941 Classification Code Fe/ Zn 5A
(2) Claniping type stud, reduced-diameter body, ASME B18.31.2, %-16 x 2, ASTM F468 nickel-copper alloy 400
(3) Tap-end stud, full body, ASME B18.3l.2, i/g NC-5 HFSX 6’/2 X 1’/8-8UN, ASTM F593 Alloy Group 2, Cold Worked Condition
(4) Continuous thread flange bolting stud, ASME BL8.3i.2, %-io UNC x 6, ASTM A193, Grade B7
(1’) Part Identification Number (PIN): Refer to SAE J2271 PIN for all stud types covered in this Standard except flange bolting studs (stud bolts).
NOTE: SAE J2271 contains part identification numbers for interference-fit tap-end studs with eight different suffixes for tap-end thread major diameters and guidance on selecting the appropriate thread configurations for both the tap-end and internal thread for the material into which the interference-fit stud is installed.