ASTM F541 Alloy Steel Eye Bolts Specification

Forged Quenched and Tempered Alloy Steel Threaded Eyebolts for low temperature applications

ASTM F541 Straight Shank Eye Bolts, Shoulder Eye Bolts

ASTM F541 specification covers forged, quenched and tempered, alloy steel threaded eyebolts with improved toughness properties and intended primarily for low temperature applications. The eyebolts are chemically and metallurgically constituted to produce a low transition temperature to minimize brittle failure. Maximum thread size is 2 1/2 (63.50 mm). The steel shall be made to a fine-grain practice using a melting process yielding a product conforming to the requirements of this specification. ASTM F541 Eyebolts shall be forged without welds. The eyebolts shall be quenched and tempered in accordance with proper practice to yield a product conforming to the requirements of this specification. The eyebolt shall be machined prior to or after heat treatment at the manufacturer's option.

ASTM 541 Chemical Requirements

Element Analysis Type 1 Type 3B
P, max Heat analysis  0.040 0.040 
Product analysis 0.050 0.045
 S, max Heat analysis  0.050  0.050 
Product analysis 0.060 0.055
 Si Heat analysis  . . .  0.15-0.35
Product analysis . . . 0.13-0.37
 Cr Heat analysis  . . . 0.45-0.65 
Product analysis . . . 0.42-0.68
 Ni Heat analysis  . . .  0.25-0.45 
Product analysis . . . 0.22-0.48
 Cu Heat analysis  . . . 0.25-0.45
Product analysis . . . 0.22-0.48
  • (A) The composition shall contain at least two of the elements shown.

ASTM 541 Mechanical Requirements

ASTM 541 Decarburization Limits

Nominal Size, In. Depth of Decarburization, Total + Partial, max
in. mm
0.250 to 0.375 0.030 0.762
0.4375 to 0.625 0.040 1.02
0.750 to 1.000 0.050 1.27
1.125 to 1.500 0.060 1.52
1.750 to 2.500 0.070 1.78

ASTM 541 Tensile Requirements

Tensile strength, min, psi (MPa) 95 000 (660)
Yield strength, min (0.2 % offset), psi (MPa) 70 000 to 100 000 (485 to 690)
Elongation in 2 in. (50 mm), min, % 22
Reduction of area, min, % 55
Brinell hardnessA 197 to 248
Rockwell B hardnessA 93 to 101

ASTM 541 Breaking Strength and Proof Load

Nominal Size and Number of Threads Tension Stress Area, in.2 Breaking Strength, min Proof Load, min
lb Mg lb Mg
0.250-20 0.0318 3 020 1.37 1 220 0.55
0.3125-18 0.0524 5 000 2.27 2 000 0.91
0.375-16 0.0775 7 400 3.35 2 960 1.34
0.4375-14 0.1063 10 100 4.60 4 040 1.84
0.500-13 0.1419 13 500 6.1 5 400 2.44
0.625-11 0.226 21 500 9.8 8 600 3.92
0.750-10 0.334 32 000 14.5 12 800 5.8
0.875-9 0.462 44 000 20.0 17 600 8.0
1.000-8 0.606 58 000 26.5 23 200 10.6
1.125-7 0.763 72 000 32.5 28 800 13.0
1.250-7 0.969 92 000 42.0 36 800 16.8
1.500-6 1.405 133 000 60.0 53 200 24.0
1.750-5 1.90 180 000 82 72 000 32.8
2.000-4.5 2.50 238 000 108 95 200 43.2
2.500-4 4.00 380 000 172 152 000 68.8

ASTM F541 Bolting Surface Treatment Specifications

ASTM F541 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

B18.15 - Type 1 Regular Pattern
B18.15 - Type 2 Shoulder Pattern

ASTM F541 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 F541 Testing Standards

E18 Test Methods for Rockwell Hardness of Metallic Materials
E21 Test Methods for Elevated Temperature Tension Tests of Metallic Materials
E112 Test Methods for Determining Average Grain Size
E139 Test Methods for Conducting Creep, Creep-Rupture,and Stress-Rupture Tests of Metallic Materials
E150 Recommended Practice for Conducting Creep and Creep-Rupture Tension Tests of Metallic Materials Under Conditions of Rapid Heating and Short Times
E151 Recommended Practice for Tension Tests of Metallic Materials at Elevated Temperatures with Rapid Heating and Conventional or Rapid Strain Rates
E292 Test Methods for Conducting Time-for-Rupture Notch Tension Tests of Materials
E328 Test Methods for Stress Relaxation for Materials and Structures
E566 Practice for Electromagnetic (Eddy Current) Sorting of Ferrous Metals
E709 Guide for Magnetic Particle Testing
F606/F606M Test Methods for Determining the Mechanical Properties of Externally and Internally Threaded Fasteners, Washers, Direct Tension Indicators, and Rivets
F1940 Test Method for Process Control Verification to Prevent Hydrogen Embrittlement in Plated or Coated Fasteners
A962/A962M Specification for Common Requirements for Bolting Intended for Use at Any Temperature from Cryogenic to the Creep Range
A788/A788M for Steel Forgings, General Requirements

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 F541 Supplementary Requirements

S1 Magnetic Particle Inspection