ASTM A320 L7 Stud Bolts

ASTM A320 Gr L7 Bolts and ASTM A320 L7M Bolt

Grade L7 typically consists of a chromium rich ferritic steel such as AISI 4140 or AISI 4142. According to the specification, these ferritic steel A320 Gr L7 Material is available in a quenched and tempered condition. The fasteners produced using the A320 Grade L7 Material is basically alloy steel intended to be used for low temperature applications especially those involving pressure vessels, valves, flanges, and fittings. As expected the routine procedure of any  American Society for Testing and Materials specification like the A320 Grade L7 Studs covers not only the chemical but also mechanical requirements including the ones mentioned here i.e. tensile strength and yield strength in addition to elongation as well as hardness.

Moreover, the materials used to make A320 Gr L7 Hdg have to conform to not only the impact energy absorption requirements that have been prescribed here, but also the recommended test temperature. There are certain mandated mechanical tests to be performed on the A320 Gr L7 Stud Bolt, namely: tension test, impact test, and hardness test. In comparison to regular carbon steels, the A320 Grade L7 Nuts manufactured from alloy steel grades tends to be more responsive towards both the mechanical as well as the heat treatments conducted on them. While grade L7 corresponds to chromium steels, the A320 Grade L7m Bolts corresponds to those steels which primarily contain chromium and molybdenum as their alloyants. Generally, quenching and tempering are performed on the A320 L7 Stud Bolts with the sole intention of developing certain desired mechanical properties. Specifically speaking, the fore mentioned heat treatment performed on the A320 L7 Bolts is done in order to optimise its tensile strength properties.

ASTM A320 Gr L7 Bolts Schedule Standard And Specification

Diameters M6 to M36
Standard forged, studs, bolts, or strain hardened bars, screws, and stud bolts
Configuration ASME B1.1 2A/3A – 2B/3B Inch

ASTM A320 Grade L7 Nuts Grades

L7 AISI 4140/4142 Quenched and tempered

Equivalent Material Of ASTM A320 L7M Bolt

L7 Bolts Type
Hex Head Bolts
M4 to M80
1040N / mm2 min
ISO 4017 (Full Thread)
ISO 4014 (Half Thread)

A320 Gr L7 Stud Mechanical Properties Database

Grade Size RA Charpy Impact
@ temp
Tensile Strength Yield Strength Elongational
L7 Up to 2-1/2 50 -150° F 125 105 16

ASTM A320 Bolts Chemical Resistance Guide

Element L7 (AISI 4140)
Carbon 0.37 - 0.49%
Manganese 0.65 - 1.10%
Phosphorus, max 0.035%
Sulfur, max 0.040%
Silicon 0.15 - 0.35%
Chromium 0.75 - 1.20%
Molybdenum 0.15 - 0.25%

ASTM A320 Grade L7m Material Sizes

Nuts Type
Hex Nut
M6 to M42
ISO 4032
Nylock Nut
M6 to M20 (Gr.8)
M10 to M24 (Gr.10)
8 & `10
DIN 982
Nylock Nut
M6 to M20 (Gr.8)
M10 to M24 (Gr.10)
8 & 10
DIN 985
Hex Weld Nut
M6 to M12
DIN 929

We supply ASTM A320 Bolts, ASTM A320 Stainless Steel Bolts in various specifications at Cost Effective Price.

3mm to 39mm
HV (430 to 530)
DIN 7980
3mm to 39mm
HV (430 to 530)
DIN 127 B
12mm to 30mm
HV (300 to 370)
IS 2016
12mm to 56mm
Rockwell 26 to 45 (HDG)
Rockwell 38 to 45 (Coated)
American Society for Testing and Materials F436M