ASTM A320 L7 Bolts Quick Spec Overview
Mortec At A Glance
Established
Since 2012 • 14 yrs in alloy fastening
Manufacturing Units
2 in-house units • Taloja & Mazgaon
Stockyard Area
8,850+ sq.ft • Ready-stock inventory
Certifications
ISO 9001:2015 • GST, IEC & MSME
Clientele
100+ clients • India & export markets
Export Reach
19+ countries • GCC, Africa & Americas
Testing Offered
Charpy, tensile & hardness • MTC EN 10204 3.1
Shipment Documents
Invoice, Packing List • COO, COI, MTC, BL & Lab Report
Table of Content
Cryogenic Rated ASME SA 320 Grade L7 Stud Bolts Manufacturer in India, Check Torque Chart
Low-temperature flange joints fail at the bolting long before they fail at the gasket, which is why buyers in Dubai, Johannesburg, Nairobi and Alberta specify ASTM A320 Grade L7 rather than a general-purpose alloy stud. Every diameter from 1/4″ through 2-1/2″ sits in our Mumbai stockyard already quenched, tempered and impact qualified at −101 °C, so a shutdown enquiry received in the morning can be picked, marked and boxed the same working day.
We machine A320 L7 stud bolts, heavy hex bolts and double-end studs from traceable 4140-type chromium-molybdenum bar, thread them to ASME B1.1 Class 2A, and release them only against a lot-specific Charpy V-notch record on the mill test certificate. Nuts to ASTM A194 Grade 4 or Grade 7 and washers to ASTM F436 are packed with the studs as a matched set, so nothing on your bolt-up sheet is left to a local purchase. Send the flange rating, quantity and coating preference, and our bolting desk confirms thread series, stud length and torque figures before you release the purchase order.
ASTM A320 L7 Bolt Specification
Share your stud schedule and quantity, we'll confirm a live ex Mumbai rate the same day, fully certified.
ASTM A320 L7 Bolt Specification – Thread Series
- ASME B1.1 Class 2A, right hand
- UNC up to 1″, 8UN above 1″
ASTM A320 Grade L7 Hex Bolts Dimensional Codes
- ASME B18.2.1 heavy hex head
- ASME B16.5 stud length practice
A320 L7 Studs Length Range
- 50 mm to 1000 mm cut lengths
- Double-end or full thread form
Stud Bolt L7 Surface Coating Options
- PTFE Xylan 1070, blue or grey
- Hot-dip galvanised, zinc, black oxide
Sa 320 L7 Fasteners Third-Party Inspection
- TUV, SGS, BV, Lloyd’s, DNV
- Witnessed impact & tensile on request
A320 L7 Bolts Marking & Traceability
- Grade symbol L7 plus maker ID
- Heat number carried to the MTC
ASTM A320 Gr L7 Material Compliance Scope
- ASME B31.3 process piping bolting
- ISO 9001:2015 controlled production
Sour Service Note For A320 L7 Studs
- Standard L7 is not a NACE grade
- Ask for L7M where MR0175 applies
ASTM A 320 L7 Studs Export Packing
- VCI wrapped, sealed in wooden cases
- Bundle marking per flange line number
ASTM A320 Grade L7 Hex Bolts Manufacturing Standards
We verify every stud against these codes at the marking bench before it moves to packing.
Charpy V-Notch Tested A320 Gr L7 Fasteners Ready Ex Stock For Offshore And Subsea, Direct Manufacturer Pricing
ASTM A320 Gr L7 Material Charpy V-Notch Impact Testing
This one test is why Grade L7 stands as its own specification, here's exactly what your lot goes through before release.
Test Bar From Your Lot
Specimens are taken from material representing the heat and heat-treat lot of your studs.
Notched And Chilled
Standard V-notch specimens are prepared and soaked down to −101 °C in the bath.
Three-Specimen Set
A set of three is broken on the pendulum and each absorbed energy value recorded.
Reported On Your MTC
Individual and average values are printed against the heat number on the certificate.
Types Of ASTM A320 L7 Bolts
Site teams call us first as their ASTM A320 L7 Bolts supplier in India since every form stays in ready stock.
ASTM A320 L7 Hex Bolts
Full & Partial Thread • 1/4″–2-1/2″- Standard hex head bolting form
- Cut to your required length list
A320 L7 Heavy Hex Bolts
ASME B18.2.1 • Head Marked- Larger across-flats bearing area
- Grade symbol rolled on the head
SA320 Gr L7 Stud Bolts
Full Thread • Flange Bolting- Standard flange bolting form
- Cut to your B16.5 length list
SA 320 L7 Socket Head Cap Screws
Allen Drive • M6–M64- Compact head for confined joints
- Precision machined socket drive
A320 Gr L7 Set Screws
Headless • Locking Applications- Holds components without a head
- Cup, cone or flat point options
ASTM A 320 L7 Eye Bolts
Lifting & Rigging Duty- Forged loop for sling or shackle
- Rated for cold-service lifting points
SA 320 L7 Threaded Rods
Full Length • Cut To Size- Continuous thread, cut on request
- Common for pipe support hangers
ASTM A320 L7 Anchor Bolts
L & J Bend • Foundation Fixing- Bent or straight foundation type
- Rated for low-temperature footings
SA 320 Gr L7 U Bolts
Pipe Clamping • Support Duty- Clamps pipe to structural steel
- Supplied with matching nuts
ASTM A320 L7 Bolts Manufacturer In Mumbai, Forging And Machining Since 2012
Share your diameter and length list, and we'll lock the quote for thirty days.
A320 L7 Heavy Hex Bolts Chemical Composition
As an ASTM A320 L7 Bolts Manufacturer in India, we certify every release against these heat analysis limits.
ASTM A320 L7 Mechanical Properties
These ASTM A320 L7 Mechanical Properties and yield strength figures cover up to 2 1/2 inch, retested on our bar.
ASTM A320 L7 Material Properties – Supporting Values
ASTM A 320 L7 Studs Equivalent Standards
Since L7 is a bolting spec, this ASTM A320 L7 Equivalent traces back to the base 4140 chromium molybdenum alloy.
ASTM / ASME (USA)
- ASTM A320 Grade L7
- ASME SA-320 Grade L7
- AISI 4140 / 4142 / 4145
- UNS G41400
DIN / EN (Germany)
- 42CrMo4
- Werkstoff 1.7225
- EN 10269 bolting steel
BS (United Kingdom)
- BS 708M40
- Formerly EN19
JIS (Japan)
- SCM440
- JIS G 4053 alloy steel
GB/T (China)
- 42CrMo
- GB/T 3077 alloy structural steel
AFNOR (France)
- 42CD4
- ISO 683-2 42CrMo4
Your A320 Gr L7 Fasteners Partner Across Africa & The Gulf
We crate and clear impact tested bolting sets for buyers across Southern Africa and the GCC.
Johannesburg, SA
Nairobi & Mombasa, Kenya
Kampala, Uganda
Dubai & Abu Dhabi, UAE
Jubail, Saudi ArabiaDurban, SAA320 Gr L7 Double End Stud Torque Chart
Each ASTM A320 L7 Bolt Torque Chart value is calculated, not generic, so verify them against your own joint design.
How These A320 L7 Bolt Torque Values Are Derived
Torque is only a proxy for the clamp load you actually want in the joint. The short-form relationship used here is T = K × D × F, where K is the nut factor set by the thread condition and lubricant, D is nominal diameter and F is the target preload. We take F as 50% of the Grade L7 specified minimum yield of 105 ksi, applied over the ASME B1.1 tensile stress area of the thread.
- Dry or as-machined threads run nearer K = 0.20, so the same clamp load needs roughly 25% more torque than the values tabulated below.
| Stud Dia | Thread | Stress Area (in²) | Preload (lbf) | Torque (ft·lbf) | Torque (N·m) |
|---|---|---|---|---|---|
| 1/2″ | 13 UNC | 0.1419 | 7,450 | 50 | 68 |
| 5/8″ | 11 UNC | 0.2260 | 11,865 | 100 | 135 |
| 3/4″ | 10 UNC | 0.3345 | 17,559 | 175 | 240 |
| 7/8″ | 9 UNC | 0.4617 | 24,241 | 285 | 385 |
| 1″ | 8 UNC | 0.6057 | 31,802 | 425 | 575 |
| 1-1/8″ | 8 UN | 0.7905 | 41,499 | 620 | 845 |
| 1-1/4″ | 8 UN | 0.9997 | 52,485 | 875 | 1,185 |
| 1-3/8″ | 8 UN | 1.2335 | 64,759 | 1,190 | 1,610 |
| 1-1/2″ | 8 UN | 1.4918 | 78,322 | 1,565 | 2,125 |
| 1-5/8″ | 8 UN | 1.7747 | 93,173 | 2,020 | 2,735 |
| 1-3/4″ | 8 UN | 2.0822 | 109,313 | 2,550 | 3,460 |
| 1-7/8″ | 8 UN | 2.4141 | 126,742 | 3,170 | 4,295 |
| 2″ | 8 UN | 2.7706 | 145,459 | 3,880 | 5,260 |
| 2-1/4″ | 8 UN | 3.5573 | 186,758 | 5,600 | 7,595 |
| 2-1/2″ | 8 UN | 4.4421 | 233,212 | 7,775 | 10,540 |
ASTM A193 Grade B7 Bolts Vs ASTM A320 Grade L7 Bolts
As an ASTM A320 L7 Bolts Exporter, this is the question we field most, what actually separates it from B7.
ASTM A193 Grade B7
- Base Alloy: Same 4140-type Cr-Mo steel
- Tensile / Yield: 125 ksi / 105 ksi, identical to L7
- Impact Testing: Not a requirement of the grade
- Service Intent: High temperature and general pressure duty
ASTM A320 Grade L7
- Base Alloy: Same 4140-type Cr-Mo steel
- Tensile / Yield: 125 ksi / 105 ksi, identical to B7
- Impact Testing: Charpy V-notch at −101 °C is mandatory
- Service Intent: Low temperature and cryogenic bolted joints
ASTM A320 Low-Temperature Bolt Grade Selection Guide
B7 and L7 differ on impact testing, not strength, while the broader A320 family also splits by diameter and service chemistry.
ASME SA 320 Grade L7 Stud Bolts Moving Into Europe & Turkey
We consolidate bolting loads for LNG, chemical and cold-storage contractors throughout the European corridor.
Aberdeen, UK
Rotterdam, NetherlandsHamburg, Germany
Milan, Italy
Istanbul, TurkeyIzmir, TurkeyASME SA 320 Grade L7 Stud Bolts Exporter In India To Jebel Ali Port, Dubai, UAE
Even small bolting lots travel at container rates through our weekly UAE consolidations.
A 320 L7 Hex Nut Size Chart
Turning a grade into a purchase order comes down to diameter, mating nut and coating, all three are covered below.
A320 L7 Heavy Hex Bolts Ordering Reference
Confirm diameter range, thread class and matching nut grade before ordering, so studs and nuts arrive correctly paired.
A320 L7 Heavy Hex Bolts – Ordering Reference
A 320 L7 Hex Nut & Washer Pairing
Stud Bolt L7 Surface Finish
We supply studs in a range of finishes, and your coating choice directly shifts the friction and torque values at installation.
A320 Gr L7 Fasteners Supplied Across The Americas & ASEAN
We despatch cold-service bolting to Canadian LNG yards, US Gulf Coast fabricators and Southeast Asian refiners.
Calgary, CanadaEdmonton, CanadaHouston, USA
Mexico
Venezuela
Singapore
Malaysia
Thailand
Philippines
Vietnam
IndonesiaSA 320 Gr L7 Nuts Applications
Grade L7 is the specified answer wherever a bolted joint must stay tight as the line runs cold.
A320 L7 Studs Price Factors
Your per piece figure depends on five variables, share yours and get a quote with zero hidden extras.
A320 Gr L7 Material Manufacturing Process
From bar to boxed stud, everything happens in house, including heat treatment, so we control the impact result ourselves.
Bar Selection
Traceable 4140-type bar drawn against heat number and chemistry.
Quench & Temper
Hardened then tempered to bring hardness under the 321 HBW cap.
Threading
Rolled or cut to Class 2A after heat treatment, never before.
Impact & Marking
Charpy set broken, then studs stamped L7 with the heat number.
A320 L7 Bolts Delivery Estimate
Pick the freight mode that fits your shutdown window, and we'll build the despatch plan around it, ocean legs follow the sailing calendar.
Off-The-Shelf Release
Held diameters are picked, marked and boxed inside 24–72 hours of order release
Ocean Freight (FCL/LCL)
The economical leg for bulk bolting, generally landing in 10–30 days
Air Cargo Priority
When a flange is open and waiting, air uplift reaches you in 3–6 days
Port-Wise Arrival Date
Name your discharge port and we commit to a dated arrival window
L7 Bolts Testing & Certification
ASTM A320 L7 Bolts Manufacturer in Mumbai confirms heat number on mill certificate, witnessed anytime.
A320 Gr L7 Fasteners Ready For Middle East Refinery & Terminal Projects
Gulf contractors get both ready inventory and mill order capacity from us, with UAE our biggest cryogenic bolting destination.
Dubai, UAESharjah, UAE
Sohar, OmanDammam, KSA
Ras Laffan, Qatar
Kuwait City
Manama, BahrainASTM A320 L7 Stud Bolts Supply References
Here's a sample of recent bolting despatches to our Gulf, African and North American customers.
1-1/4″ A320 L7 Stud Bolts – LNG Loading Line Flanges
Xylan 1070 coated, A194 Gr 7 nuts, witnessed Charpy at −101 °C.
LNG Terminal Contractor, UAE
DUBAI, UAE3/4″ ASME SA 320 L7 Studs – Air Separation Cold Box
Full thread studs with two nuts each, EN 10204 3.1 MTC.
Industrial Gas Plant, South Africa
JOHANNESBURG, SOUTH AFRICA1″ A320 L7 Heavy Hex Bolts – Subsea Manifold Frame
Hot-dip galvanised, dimensional report issued per bundle.
Subsea EPC Contractor, Canada
CALGARY, CANADA7/8″ A320 Gr L7 Double End Studs – Valve Bonnet Package
Plain shank studs, PMI verified, third-party witnessed release.
Valve Refurbishment Works, Kenya
MOMBASA, KENYA1-1/2″ ASTM A320 L7M Studs – Sour Gas Separator Skid
Hardness checked piece by piece, matched Gr 7M nuts supplied.
Gas Processing Contractor, Saudi Arabia
JUBAIL, SAUDI ARABIA5/8″ A320 L7 Threaded Rod – Cold Store Pipe Support
One metre bars, zinc plated, cut lengths supplied loose.
Cold Chain Contractor, Turkey
ISTANBUL, TURKEYTop Export Countries
UAE
Turkey
Canada
United Kingdom
Saudi Arabia
Singapore
United States
Mexico
Thailand
Italy
Netherlands
Germany
Philippines
Malaysia
Uganda
Indonesia
South Africa
Vietnam
Venezuela
ASTM A320 Standard Bolting Supplier In Chennai With Lot-Wise Impact Records
We send the Charpy report to your QA file before the material even reaches your gate.
ASTM A320 L7 Bolts FAQs
Here are the five questions our bolting desk hears most before a purchase order goes out.
What is the A320 Gr L7 Material equivalent?
Grade L7 is a chromium-molybdenum steel (AISI 4140/4142/4145, UNS G41400), similar to EN 42CrMo4, BS 708M40, JIS SCM440 and GB 42CrMo. ASME SA-320 L7 is its pressure-vessel equivalent.
What is the yield strength of ASTM A320 Grade L7 Stud Bolts?
Grade L7 (up to 2-1/2″) requires 105 ksi minimum yield, 125 ksi minimum tensile, 16% elongation, 50% reduction of area and a maximum hardness of 321 HBW.
What sizes are A320 L7 Heavy Hex Bolts available in?
We stock 1/4" to 2-1/2" (M6-M64) in stud bolts, heavy hex bolts, and threaded rod. Above 2-1/2′, Grade L43 is the low-temperature equivalent.
What torque is used for Sa 320 Gr L7 Nuts?
Torque isn’t fixed by ASTM A320 - we calculate it as T = K × D × F, giving roughly 425 ft·lbf for a 1″ stud with moly lubricant. Dry threads need about 25% more torque for the same clamp load.
What is the price of A320 Gr L7 Double End Stud?
Grade L7 stud bolt pricing depends on size, coating, and testing requirements, quoted against the day’s 4140 bar rate. Send your bolting schedule for a firm ex-Mumbai quote.
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