ASTM A320 Grade L7 Fasteners Manufacturer & Suppliers
ASTM A320 Grade L7 fasteners were designed to handle harsh operations within low-temperature and high-pressure conditions. The development of the ASTM A320 Grade L7 specification was a result of low-temperature bolting materials applied in pressure vessels, valves, flanges and fittings to ensure satisfactory performance in the circumstances where temperature and stress are critical. These fasteners are made of high-strength alloy steel and improved by means of the controlled heat treatment, providing them with great toughness, durability, and corrosion resistance. ASTM A320 L7 bolts, studs, nuts, and screws will ensure similar mechanical properties even when in the state of freezing and in the state of cryogenic environment; thus, they are applicable in offshore platforms, petrochemical plants, refineries, and power generation facilities.
ASTM A320 L7 Hex Head Bolts are to be used when one wants to keep the strength and integrity of the bolt at temperatures as low as -150°F (-101°C). They possess high tensile and yield strength, which makes them an excellent choice to use in LNG plants, Arctic installations and other cryogenic applications. The dimensional stability of the bolts is increased during the tempering process, which makes the bolts resistant to vibration, pressure, and thermal stress without deformation and loss of performance.
The ASTM A320 L7 Hex Head Screws are produced with regulated microstructure and appropriate thermal treatment, which contributes to the minimisation of the brittleness and increases the fatigue resistance. This renders them dependable in extremely sensitive systems like pressure vessels, heat exchangers, valves, pipelines and flanges of industries. ASTM A320 Grade L7 washers and hex nuts are also resistant to stress corrosion cracks and hydrogen embrittlement, which can be used to increase the service life of equipment that is used in high-pressure or extreme cooling conditions.
Request QuoteWhat is ASTM A320 Grade L7?
ASTM A320 Grade L7 is a strong alloy steel fastener made with chromium and molybdenum designed for low temperature use. These fasteners go through quenching and tempering which makes them stronger and helps them stay tough even in freezing weather. That is why they are used in places where parts cannot afford to crack or break. ASTM A320 L7 bolts studs and nuts also resist corrosion stress cracking and oxidation which makes them a reliable choice for cold and demanding environments where strength and durability really matter.
These fasteners are used in cryogenic storage tanks, low temperature pipelines, LNG plants, pressure vessels, heat exchangers and industrial valves. They can handle thermal shock and stay strong even in freezing environments which makes them important in oil and gas petrochemical and power generation industries. Whether it is holding pressure parts together or dealing with cryogenic fluids ASTM A320 Grade L7 fasteners are known for their strength reliability and long life in some of the toughest working conditions.
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Types of ASTM A320 L7 Fasteners
ASTM A320 Grade L7 fasteners are made to perform in extremely cold environments and are available in different types to fit a wide range of industrial needs. These fasteners provide strong tensile strength good toughness and resistance to corrosion which makes them ideal for sub zero conditions.
We offer a complete range of ASTM A320 Gr L7 bolts screws and stud bolts designed for use in low temperature and high strength applications across various industries:
- ASTM A320 L7 Structural Bolts
- ASTM A320 L7 Heavy Hex Bolts
- ASTM A320 L7 Hex Bolts
- ASTM A320 L7 Hexagon Head Bolts
- ASTM A320 L7 Machine Bolts
- ASTM A320 Grade L7 T Bolts
- ASTM A320 Gr. L7 Eye Bolt
- ASTM A320 L7 Foundation Bolts
- Alloy Steel A320 Gr L7 J Bolts
- ASTM A320 L7 Button Head Bolt
- ASTM A320 L7 Anchor Bolts
- ASTM A320 L7 Long Bolts
- ASTM A320 L7 Carriage Bolt
- ASTM A320 L7 Elevator Bolt
- ASTM A320 L7 Timber Bolts
- ASTM A320 L7 Square Bolt
- ASTM A320 L7 Metric Bolt
- ASTM A320 L7 Plow Bolts
- Alloy Steel Gr. L7 U Bolts
- ASTM A320 L7 Flange Bolts
- ASTM A320 L7 Socket Set Screw
- ASTM A320 L7 Self Drilling Screw
- ASTM A320 L7 Socket Head Cap Screw
- ASTM A320 L7 Hex Head Screws
- ASTM A320 L7 Wood Screw
- ASTM A320 Gr. L7 Eye Screw
- ASTM A320 Gr. L7 Wing Screw
- ASTM A320 L7 Self Tapping Screws
- ASTM A320 Gr. L7 Roofing Screw
- ASTM A320 L7 Phillips Head Screw
- ASTM A320 L7 Decking Screw
- ASTM A320 L7 Machine Screw
- ASTM A320 L7 Thumb Screw
- ASTM A320 L7 Drywall Screws
- ASTM A320 L7 Chipboard Screw
- ASTM A320 L7 Metric Set Screws
- Alloy Steel L7 Sems Screw
- ASTM A320 L7 Thread Rolling Screw
- ASTM A320 L7 Full Threaded Stud Bolts
- ASTM A320 L7 Half Threaded Stud Bolts
- Alloy Steel ASTM A320 L7 Threaded Rod
- ASTM A320 L7 Double Ended Studs
- ASTM A320 L7 Tap End Stud Bolt
- Alloy Steel ASTM A320 L7 Tie Rods
- Alloy Steel A320 Grade L7 Studs
- ASTM A320 L7 Single End Stud Bolts
- A320 Gr.L7 Reduced Shank Stud Bolt
- A320 L7 Continuous Threaded Stud Bolt
- A320 L7 Partial Threads Stud Bolt
- SA320 / A320 L7 Heavy Stud Bolts
All ASTM A320 Grade L7 fasteners are manufactured and supplied by Unifit Fastener, conforming to international standards such as ASTM and ASME. We offer standard and customized sizes ensuring precision fit and reliable performance in the most demanding operating environments.
ASTM A320 Grade L7 Chemical Composition
ASTM A320 Grade L7 fasteners are produced with a controlled alloy mix to deliver strength and toughness in low-temperature service. Their chemical balance helps improve corrosion resistance and ensures stable performance in pressure equipment.
| Element | Content (%) | Allowed Variation |
|---|---|---|
| Carbon | ≤ 0.08 | +0.01 |
| Manganese | ≤ 2.00 | ±0.04 |
| Phosphorus | ≤ 0.04 | +0.005 |
| Sulfur | ≤ 0.03 | +0.005 |
| Silicon | ≤ 1.00 | ±0.05 |
| Nickel | 24.00 – 27.00 | ±0.20 |
| Chromium | 13.50 – 16.00 | ±0.20 |
| Molybdenum | 1.00 – 1.50 | ±0.05 |
| Titanium | 1.90 – 2.35 | ±0.05 |
| Aluminium | ≤ 0.35 | +0.05 |
| Vanadium | 0.10 – 0.50 | ±0.03 |
| Boron | 0.001 – 0.010 | −0.0004 to +0.001 |
The ASTM A320 Grade L7 chemical composition ensures resistance to embrittlement and superior impact performance in sub-zero temperatures.
ASTM A320 Grade L7 Raw Material
The following table outlines the key raw material of ASTM A320 Grade L7 fasteners, crucial for their performance in low-temperature environments.
| Grade | Raw Material Description |
|---|---|
| ASTM A320 L7 | Alloy steel, AISI 4140/4142 quenched and tempered |
ASTM A320 Grade L7 Material Specification for Fasteners
| Specification | Details |
|---|---|
| Specifications | ASTM A320 / ASME SA320 |
| Length | 3mm to 200mm |
| Size | 3/6″ to 2″, M3 – M56, Custom Sizes |
ASTM A320 Grade L7 Mechanical Properties
ASTM A320 Grade L7 fasteners are designed to maintain high strength and toughness in low-temperature service. Their mechanical properties ensure reliable performance in pressure systems and critical assemblies.
| Size | Tensile Strength (ksi, min) | Yield Strength (ksi, min) | Charpy Impact 20-ft-lbf @ temp | Elongation (%) min | Reduction of Area (%) min | Hardness (max) |
|---|---|---|---|---|---|---|
| Up to 2-½ | 125 | 105 | -150° F | 16 | 50 | C35 |
These mechanical properties ensure ASTM A320 Grade L7 fasteners maintain their integrity and perform reliably in extreme low-temperature environments.
A320 L7 vs. A193 B7 Fasteners – Key Differences
When comparing the differences of A320 L7 and A193 B7 fasteners, it’s essential to consider their unique strengths and optimal use cases.
| Feature | A320 L7 | A193 B7 |
|---|---|---|
| Service Temperature | Low (Cryogenic) | High (Elevated) |
| Applications | LNG, Sub-zero | Boilers, Valves, Steam |
| Material Treatment | Quenched & Tempered | Quenched & Tempered |
| Standard | ASTM A320 | ASTM A193 |
ASTM A320 Grade L7 Fasteners Standards
The ASTM A320 Grade L7 fasteners are crafted in compliance with rigorous industry standards to ensure exceptional performance in low-temperature applications.
| Hexagon Bolt / Set Screws | Stud Bolt | Hexagon Nuts | Socket Cap screws |
|---|---|---|---|
| DIN 931 | BS4882 | DIN 934 | DIN 912 |
| DIN 933 | DIN 976 | BS 1768 | DIN 6912 |
| BS 1768 | BS 1769 | DIN 7984 | |
| UNI 5731 | BS 1083 | ANSI B18.3 | |
| UNI 5739 | BS 3692 | ISO 4762 | |
| ISO 4014 | ISO 4032 | UNI 5931 | |
| ISO 4017 | ISO 4033 | BS 2470 | |
| BS 1769 | ANSI B18.2.2 | BS 4168 | |
| BS 3692 | |||
| ANSI B18.2.1 |
| Socket & Slotted Set Screws | Socket & Slotted Countersunk Screws | Studs | Washers |
|---|---|---|---|
| DIN 913 | DIN 963 | DIN 938 | DIN 125 |
| DIN 914 | DIN 7991 | DIN 939 | DIN 9021 |
Applications of ASTM A320 Grade L7 Fasteners
ASTM A320 Grade L7 fasteners are built for tough environments where things get really cold and strength still matters. They’re used in places where equipment needs to stay reliable no matter how low the temperature drops. You’ll find these fasteners used across industries that can’t afford failure in extreme cold like:
- Heavy Engineering Industries
- Petro-Chemical Industries
- Shipbuilding Industries
- Fertilizer Plants
- Civil Construction Industries
- Power Generation Units (Nuclear, Hydro, or Thermal)
- Civil Industries
- Oil Expansion Projects
- Offshore & Onshore Oil Towers
- Valves
- Pressure Vessels
- Home Fittings
- Pumps
- Railways
- Steel Plants
The benefits of ASTM A320 Grade L7 bolts
- Outstanding Low-Temperature Performance: L7 bolts are designed to be strong and tough even at very low temperatures, being reliable even at -150°C (-101°C). This renders them to be applicable to cryogenic systems, LNG operations and the Arctic.
- High Mechanical Strength: These bolts are alloyed with alloying elements such as chromium and molybdenum and heat treated to provide them with high tensile and yield strengths. They are capable of pressure, vibration and thermal stress on pressure vessels, valves and flanges.
- Good Corrosion Resistance: Although it is not as resistant to corrosion as stainless steel, the chromium still offers solid resistance to oxidation and overall corrosion under a large variety of industrial conditions.
- Application Versatility: The L7 bolts, when used with ASTM A194 Grade 7 nuts, make a secure bolting system so that the equipment to be used in low-temperature service can be installed without contradiction and safely in high-critical installations.
ASTM A320 Grade L7 Price in India for Fasteners
Unifit Fastener offers the best prices for ASTM A320 L7 fasteners in India without compromising on quality. Whether you need A320 L7 hex bolts, L7 studs or heavy hex nuts we supply fasteners that meet international standards and perform well in low temperature conditions. Our products are known for their strength, durability and reliable performance even in extreme environments. With fast delivery and technical support we make sure you get the right fasteners on time so your project stays safe, strong and on schedule.
Request QuoteFAQ’s About ASTM A320 GR L7 Fasteners
What is ASTM A320 GR L7 material?
ASTM A320 Grade L7 is an alloy steel bolting material specifically manufactured for low-temperature service. It is quenched and tempered to achieve high strength, toughness, and resistance to brittle failure, making it suitable for pressure vessels, valves, flanges, and fittings operating in sub-zero environments.
Is ASTM A320 L7 stainless steel?
No. ASTM A320 L7 is not stainless steel. It is typically produced from chromium-molybdenum alloy steel such as AISI 4140/4142. While it offers good corrosion resistance due to its alloy content, it does not provide the same level of corrosion resistance as stainless steels.
What is the difference between A320 L7 and B7?
A320 L7 fasteners are designed for low-temperature service with mandatory impact testing, while B7 fasteners are meant for ambient or high-temperature applications and do not require low-temperature impact testing.
What is ASTM A320 Grade L7?
ASTM A320 Grade L7 is a specification for alloy-steel bolting materials that are intended for low-temperature service, especially in pressure vessels, valves, flanges and fittings.