API 6A ASTM A320 L43 Stud Bolts for High-Pressure Oil & Gas Applications
ASTM A320 Grade L43 stud bolts are high-strength alloy steel fasteners used for demanding oil & gas and pressure-control applications where reliable mechanical performance, controlled material properties and dimensional accuracy are required.
API 6A fasteners manufactured with ASTM A320 L43 material can be used for applicable pressure-containing equipment and Industrial Engineering Works assemblies, including wellheads, Christmas trees, valves, choke manifolds and flanged connections. Their combination of strength, toughness and controlled heat treatment makes them suitable for demanding onshore and offshore environments.
Why Choose ASTM A320 Grade L43 for API 6A Fasteners?
Higher Strength than Standard L7 Fasteners
ASTM A320 L43 provides high-strength mechanical properties for applications where the specified design requires higher-strength alloy steel bolting.
Excellent Low-Temperature Toughness
L43 alloy steel is designed for applications requiring controlled toughness and mechanical performance at lower service temperatures when specified.
Manufactured from AISI 4340 Alloy Steel
ASTM A320 Grade L43 is an alloy steel fastener material based on a nickel-chromium-molybdenum alloy steel composition.
Reliable Performance Under High Pressure
L43 stud bolts provide the mechanical strength required for applicable high-pressure bolting assemblies used in oil & gas and pressure-control equipment.
Technical Specifications
Available Product Types
Fully Threaded Stud Bolts
Fully threaded stud bolts manufactured in ASTM A320 L43 alloy steel for applicable high-pressure and Industrial Engineering Works applications.
Double End Studs
Double end studs with specified threaded sections and body dimensions for custom equipment and flange assemblies.
Tap End Studs
Tap end studs manufactured according to required dimensions and thread configurations for applicable equipment connections.
Heavy Hex Bolts
High-strength heavy hex bolts can be supplied in L43 material where required by the application and specification.
Heavy Hex Nuts
Compatible heavy hex nuts can be supplied according to the required material grade, thread and dimensional specification.
Washers
Washers can be supplied for compatible bolting assemblies according to customer requirements.
Applications
Inspection & Quality Assurance
PMI Testing
Positive Material Identification can be performed to verify the material grade and support material traceability.
Hardness Testing
Hardness testing is performed according to the applicable specification and customer requirements.
Charpy Impact Testing
Charpy impact testing can be provided where required to verify toughness characteristics for the specified service conditions.
Heat Number Traceability
Heat numbers are maintained to provide traceability from raw material through manufacturing, testing and final supply.EN 10204 3.1 / 3.2 Certificates
EN 10204 3.1 / 3.2 Certificates
Material certificates and inspection documentation can be supplied according to the applicable EN 10204 certification requirement.
Third-Party Inspection
Independent third-party inspection can be arranged according to customer, EPC or project requirements.
Dimensions & Thread Options
| Parameter | Details |
|---|---|
| Material | ASTM A320 Grade L43 |
| Diameter | Standard & Custom |
| Length | Standard & Custom |
| Thread Type | UNC / UNF |
| Thread Series | 8UN where specified |
| Custom Threads | Available as required |
| Configuration | Fully Threaded, Double End, Tap End |
| Finish | As specified |
| Certification | MTC / Inspection Documentation |
Why Choose Industrial Engineering Works?
Frequently Asked Questions
What are API 6A Fasteners?
API 6A fasteners are fasteners used in applicable equipment and bolting assemblies associated with API 6A pressure-control and wellhead equipment. The applicable fastener material and qualification requirements depend on the equipment specification and project requirements.
What is ASTM A320 Grade L43?
ASTM A320 Grade L43 is a high-strength alloy steel fastener grade intended for applications requiring specified mechanical properties and toughness characteristics.
What is the difference between ASTM A320 L43 and L7?
Both are alloy steel fastener grades, but their specified chemistry, mechanical properties and toughness requirements differ. The appropriate grade should be selected based on the equipment design, service conditions and applicable specification.
Is ASTM A320 L43 suitable for low-temperature service?
L43 can be used for applications requiring specified low-temperature toughness when the material, testing and service requirements are properly defined. The actual suitability should be confirmed against the project specification and operating conditions.
Do you manufacture custom stud bolt lengths?
Yes. ASTM A320 L43 stud bolts can be manufactured in custom lengths, diameters and thread configurations according to customer drawings and technical requirements.
Can you provide MTC and inspection certificates?
Yes. Material Test Certificates and applicable inspection documentation can be supplied according to the required certification level, including EN 10204 3.1 / 3.2 where specified.