ASTM A320 L7 A193 B7 Dual Certified Heavy Hex Bolts
Standard: ASME/ANSI B18.2.1, ASME/ANSI B18.2.3.7M Various types of head are also available
Inch Size: 1/2”-2.3/4” with various lengths
Metric Size: 1/2-M72 with various lengths
Grade: ASTM A320 L7, ASTM A193 B7
Finish: Black Oxide, Zinc Plated, Zinc Nickel Plated, PTFE etc.
Packing: Bulk about 25 kgs each carton, 36 cartons each pallet
Advantage: High Quality and Strict Quality Control, Competitive Price,Timely Delivery; Technical Support, Supply Test Reports
Please feel free to contact us for more details.
ASTM A320
Scope Originally approved in 1948, the ASTM A320 specification covers alloy steel and stainless steel bolting materials for low temperature service. 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. Below is a basic summary of a few of the common grades within the ASTM A320 specification. A number of other less common grades of ASTM A320 exist, but not covered in the description below.| L7 Alloy steel | AISI 4140/4142 Quenched and tempered |
| L43 Alloy steel | AISI 4340 Quenched and tempered |
| B8 Class 1 Stainless steel | AISI 304, carbide solution treated |
| B8M Class 1 Stainless steel | AISI 316, carbide solution treated |
| B8 Class 2 Stainless steel | AISI 304, carbide solution treated, strain hardened |
| B8M Class 2 Stainless steel | AISI 316, carbide solution treated, strain hardened |
| Grade | Size | Tensile, ksi, min | Yield, ksi, min |
Charpy Impact 20-ft-lbf @ temp |
Elong, %, min | RA, %, min |
| L7 | Up to 21/2 | 125 | 105 | -150° F | 16 | 50 |
| L43 | Up to 4 | 125 | 105 | -150° F | 16 | 50 |
|
B8 Class 1 |
All | 75 | 30 | N/A | 30 | 50 |
|
B8M Class 1 |
All | 75 | 30 | N/A | 30 | 50 |
|
B8 Class 2 |
Up to 3/4 | 125 | 100 | N/A | 12 | 35 |
| 7/8 - 1 | 115 | 80 | N/A | 15 | 35 | |
| 11/8 - 11/4 | 105 | 65 | N/A | 20 | 35 | |
| 13/8 - 11/2 | 100 | 50 | N/A | 28 | 45 | |
|
B8M Class 2 |
Up to 3/4 | 110 | 95 | N/A | 15 | 45 |
| 7/8 - 1 | 100 | 80 | N/A | 20 | 45 | |
| 11/8 - 11/4 | 95 | 65 | N/A | 25 | 45 | |
| 13/8 - 11/2 | 90 | 50 | N/A | 30 | 45 |
| Grade | Nuts | Washers |
| L7 | A194 Grade 4 or 7 | F436 |
| L43 | A194 Grade 4 or 7 | F436 |
| B8 Class 1 | A194 Grade 8 | SS304 |
| B8M Class 1 | A194 Grade 8M | SS316 |
| B8 Class 2 | A194 Grade 8, strain hardened | SS304 |
| B8M Class 2 | A194 Grade 8M, strain hardened | SS316 |
Wheatley Windmill Milling Day. Spur wheel and the stone nut on the ground floor transfer power from the main shaft to the millstones on the floor above.