ASTM A320 Grade L7 is heat treated chromium molybdenum alloy steel (AISI 4140/AISI 4140H) with notch toughness properties. Please find chemical composition, mechanical properties, impact test requirement, and reference standards for product dimensions, threads, coatings and recommended nuts and washers.

Sep 9, 2016 · ASTM A320-L7 is a specification covering bolts, studs, and screws intended for low temperature service. Portland Bolt regularly supplies both plain finish and hot-dip galvanized A320-L7 fasteners to numerous customers in Canada and Alaska.Recently in our Portland Bolt Live Chat, an engineer asked this question as he needed to know what grade of nuts and washers to specify on his project plans.

Aug 17, 2015 · @Eli- A320 L7 bolts are required to have a charpy test performed, whereas for A194 gr.7 nuts, the charpy is a supplemental requirement. When the test has been performed, they are then marked and sold as A194 gr.7L nuts. ASTM recommends that charpy’d nuts be used with A320 L7 bolts, so A194 gr.7L nuts should be used.

ASTM A193 B7 vs A320 L7 Stud Bolts. ASTM A193 B7 is a Bolting specification for medium-high temperature applications. It is a heat treated Chromium Molybdenum steel and is considered for applications up to 450°C (840°F).. ASTM A320 L7 has the same chemical and physical properties as B7, with additional Charpy V Notch tests taken at …

A320 bolts will use A194 heavy hex nuts. There are multiple grades within the A194 specification. The appropriate grade of A194 nut will be determined by the chemistry and strength of the fastener grade. ... A194 Heavy Hex Nut Grade; A320 Grade L7: 4 or 7: A320 Grade L7M: 7M: A320 Grade B8 (Class 1 and 2) 8: A320 Grade B8M (Class 1 and 2) 8M ...

They are a common high strength nut used with stud bolts for high and low temperature service, such as B16 and L7. When low temperature requirements are specified for Grade 7 nuts, the Charpy test procedures and requirements as defined in Specification A320/A320M for Grade L7 will apply. Grade markings consists of the grade symbol "7L".

ASTM A320 Grade L7. ASTM A320 Grade L7 is a standard specification for high tensile 4140 alloy steel bolting materials, intended for use in low temperature services. The term "bolting material" as used in this specification covers, rolled, forged or strain hardened bars, bolts, screws, studs and stud bolts.

This standard covers rolled, forged, or strain hardened bars, bolts, screws, studs, and stud bolts used for pressure vessels, valves, flanges, and fittings. Like the ASTM A193 specification, unless otherwise specified, the 8UN thread series is specified on fastener larger than 1” in diameter. ... L7 Alloy steel: AISI 4140/4142 Quenched and ...

Stud Bolts, ASTM A320 / SA320 Grade L7, Grade 7 Heavy Hex Nut, Plain, Assembly 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 …

ASTM A320 is a standard material specification covering alloy and stainless steel bolting materials for pressure vessels, valves, flanges, and fittings for low temperature services. ASTM A320 specification includes chemical composition, mechanical properties, dimensional reference standards, recommended nuts and washers for grades like L7, L43, B8, B8M, B8C, B8T and many others with notch ...