Blog
  2. ASTM
  3. Transmission Bolts
  4. ASTM F901 Specification

ASTM F901 Aluminium Bolts Specification

Aluminium Transmission Tower Bolts

ASTM F901 Hex Bolts, Square Bolts, Tower Bolts & Nuts

ASTM F901 specification covers aluminum structural bolts and nuts for use in the construction of aluminum transmission towers, substations, and similar aluminum structures. Diameters of bolts and nuts furnished to this specification are 5/8 , 3/4 , and 7/8 Inch. Bolts shall be manufactured from Alloy 2024 and nuts from Alloy 6061 or 6262.

ASTM F901 Chemical Composition

UNS Designation Number Alloy General Name AlC Cr Cu Fe Mn Si Ti Zn Mg Other Elements
Each Total
ASTM F901 Grade A92024 2024 Aluminum 2024 Balance 0.10 3.8-4.9 0.50 0.30-0.9 0.50 0.15 0.25 1.2-1.8 0.05 0.15
ASTM F901 Grade A96061 6061 Aluminum 6061 Balance 0.04-0.35 0.15-0.40 0.7 0.15 0.40-0.8 0.15 0.25 0.8-1.2 0.05 0.15
ASTM F901 Grade A96262 6262 Aluminum 6262 Balance 0.04-0.14 0.15-0.40 0.7 0.15 0.40-0.8 0.15 0.25 0.8-1.2 0.05D 0.15

ASTM F901 Sample Size and Acceptance for Mechanical Property Tests

Number of Pieces in Lot Acceptance Criteria
Number of Tests Acceptance Number Rejection Number
50 and under 2 0 1
51 to 500 3 0 1
501 to 35 000 5 0 1
35 001 to 100 000 8 0 1
  • (A) Limits are in percent, maximum, unless shown as a range or stated otherwise.
  • (B) Analysis shall regularly be made only for the elements specified in this table. If, however, the presence of other elements is suspected or indicated in amounts greater than the specified limits, further analysis shall be made to determine that these elements are not present in excess of the specified limits.
  • (C) Balance shall be arithmetically computed by deducting the sum of the other named elements from 100.
  • (D) Lead 0.4-0.7 %; bismuth 0.4-0.7 %.

ASTM F901 Tensile Strength of 2024-T4 Bolts and Proof Loads for 6061-T6 and 6262-T9 NutsA

Bolt Size, in. Tensile Strength, min, lbf (kN)
5/8 12 400 (55)
3/4 18 400 (82)
7/8 25 400 (113)
  • (A) Based on a tensile unit stress of 55 000 psi (380 MPa) and the thread stress area calculated as follows: 
  • As = 0.7854[ D - (0.9743/n)) ]2
  • where:
  • As = stress area,
  • D = nominal diameter, and
  • n = threads/in.

ASTM F901 Length of Full Body for BoltsA

Length of Bolt, in. Color Code Bolt Diameter, in.
5/8 3/4 7/8
1 Red . . . 3/16 . . .
11/4 Blue 1/16 3/16 . . .
11/2 Gold 1/4 1/4 . . .
13/4 Green 1/2 1/2 7/16
2 Red 3/4 3/4 11/16
21/4 Blue 1 1 15/16
21/2 Gold 11/4 11/4 13/16
23/4 Green 11/2 11/2 17/16
3 Red 13/4 13/4 111/16
31/4 Blue 2 2 115/16
31/2 Gold 21/4 21/4 23/16
33/4 Green 21/2 21/2 27/16
4 Red 23/4 23/4 211/16
  • (A) The length of full body is the distance from the underside of the head to the first scratch of thread on bolts with machine-cut threads, or top of the extrusion angle for bolts with rolled threads with a tolerance of ± 1/32 in. for 5/8- and 3/4-in. size bolts, and ± 1/16 in. for 7/8-in. size bolts.

ASTM F901 Heat Treatment

Alloy Fastener Condition
2024-T4 bolts solution treated and naturally aged
6061-T6 nuts solution treated and artificially aged
6262-T9 nuts solution treated, artificially aged, and cold worked

ASTM F901 Bolting Surface Treatment Specifications

ASTM F901 Bolting Components Marking

Product Shall be Marked with our manufacturing trade mark "TorqBolt" or "TB" along with the designated Grade.
Grade and manufacturer’s identification symbols shall be applied to one end of studs and to the heads of bolts and screws of all sizes. (If the available area is inadequate, the grade symbol may be marked on one end and the manufacturer’s identification symbol marked on the other end.) For bolts and screws smaller than 1⁄4 in. [6 mm] in diameter and studs smaller than 3⁄8 in. [10 mm] in diameter and for 1⁄4 in. [6 mm] in diameter studs requiring more than a total of three symbols, the marking shall be a matter of agreement between the purchaser and the manufacturer.

ASME Dimensional Standards

B18.31.2 Imperial Continious Thread, Double End Reduced & Full Body Studs
B18.31.3 Threaded Rods (Inch Series)
B16.5 Imperial Full Thread Stud Bolts
B16.5 Metric Full Thread Stud Bolts
B18.2.1 Imperial Square and Hex Bolts and Screws
B18.3 Imperial Hexagon Socket and Spline Socket Screws
B18.2.2 Imperial Square, Hex, Heavy Hex, Lock, Heavy Hex Lock Nuts

ASTM F901 Bolting Certifications

  • EN 10204 3.1
  • EN 10204 3.2
  • PED 2014/68/EC
  • MERKBLATT AD 2000 W2/W7/W10
  • API 20 E BSL 1/ BSL 2
  • NACE MR 0175
  • NACE MR 0103

ASTM F901 Testing Standards

B565 Test Method for Shear Testing of Aluminum and Aluminum-Alloy Rivets and Cold-Heading Wire and Rods
E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
E55 Practice for Sampling Wrought Nonferrous Metals and Alloys for Determination of Chemical Composition
E101 Test Method for Spectrographic Analysis of Aluminum and Aluminum Alloys by the Point-to-Plane Technique
E227 Test Method for Optical Emission Spectrometric Analysis of Aluminum and Aluminum Alloys by the Point-to-Plane Technique
F606/F606M Test Methods for Determining the Mechanical Properties of Externally and Internally Threaded Fasteners, Washers, Direct Tension Indicators, and Rivets
F1470 Practice for Fastener Sampling for Specified Mechanical Properties and Performance Inspection

ASME Threading Specifications

ASME B1.1 Unified Inch Screw Threads (UN and UNR Thread Form)
ASME B1.3 Screw Thread Gaging System for Dimensional Acceptability - Inch Screw Threads (IN, UNR, and UNJ)

ASTM F901 Supplementary Requirements

S1 Shipment Lot Testing
S2 Product Marking