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Specification Bolts & Nuts Manufacturers

ASME SA194

ASME SA194 2H / 2HM / 4 / 7 / 7L / 7M / 8/ 8M / 8MA:

ASME SA194 (ASTM A194) covers carbon steel and stainless steel alloy nuts that are suitable for high-temperature and high-pressure applications. High-strength ASME SA194 Grade 2H nuts are most commonly used in the petrochemical and energy industries due to their excellent mechanical properties and reliability.

The standard nut geometry generally conforms to ANSI B18.2.2, Table 10, UNC Series Class 2B or 8-UN Series Class 2B, or to the metric standard ASTM A194M (ASME SA194) / EN ISO 4033.

A194 2H: Carbon Steel Heavy Hex Nuts; Quenched & Tempered

A194 2HM: Carbon Steel Heavy Hex Nuts; Quenched & Tempered

A194 4: Carbon-Molybdenum Heavy hex Nuts; Quenched & Tempered

ASME SA320 L7 / L43 / B8 / B8M

ASME SA320 fasteners are widely used for low-temperature applications in the petrochemical industry and related fields. This ASME and ASTM standard covers carbon steel and stainless steel alloy bolting materials specifically designed for service under low working temperatures. The specification also includes fasteners used in pressure vessels, valves, fittings, and flanges where toughness and reliability at low temperatures are critical.

Below is a brief summary of ASME SA320 / ASTM A320 along with its corresponding standard specifications:

SA320 L7 Alloy steel, AISI 4140/4142; Quenched and tempered

SA320 L43 Alloy steel, AISI 4340; Quenched and tempered

ASME SA193 B8M/ SA320 B8M

At BBI, we manufacture stud bolts and screws in A193 B8M and A320 B8M grades. These grades are nickel-chromium, non-hardened austenitic stainless steels, strengthened through solution annealing and cold working. Compared to Type 304 stainless steel, B8M grade offers superior corrosion resistance, particularly against chloride-induced pitting.

A193 B8M and A320 B8M fasteners are widely used in heat exchangers, pressure vessels, furnace components, and across industries such as chemical processing, pharmaceuticals, food processing, textiles, paper, photographic, and orthopedic equipment manufacturing. They exhibit excellent corrosion resistance in atmospheric conditions and in the presence of salts, food substances, and organic acids, making them significantly more resistant than standard austenitic steels.

INCOLOY® Alloy 925 UNS N09925

INCOLOY® 925 is an austenitic, precipitation-hardened alloy with a nickel–iron–chromium base and additions of titanium, molybdenum, aluminum, and copper. It offers an excellent combination of high mechanical strength and outstanding corrosion resistance, making it a superior, high-performance grade compared to INCOLOY® alloy 825.

This alloy is characterized by its exceptional resistance to general corrosion, stress-corrosion cracking, and crevice corrosion in a wide range of aqueous environments, including those containing chlorides and sulphides. It is therefore highly suitable for demanding, aggressive service conditions.

 
 

ASTM A193 B8R NITRONIC 50 XM-19

At EBB, we manufacture stud bolts and nuts in ASTM A193 B8R Nitronic® 50 (XM-19) stainless steel, a premium austenitic alloy that offers a unique combination of high strength and exceptional corrosion resistance. This grade provides significantly higher corrosion resistance than Types 316, 316L, 317, and 317L, along with nearly twice the yield strength at room temperature.

ASTM A193 B8R Nitronic® 50 (XM-19) also exhibits excellent mechanical properties at both elevated and sub-zero temperatures. Unlike many other austenitic stainless steels, it does not become magnetic when cooled or cold-worked to sub-zero temperatures. The high-strength (HS) version of this material offers a yield strength approximately three to four times greater than that of Type 316 stainless steel, making it ideal for demanding structural and corrosive service applications.

 
 
 
 
 
 
 
 
 
 
 

INCONEL® alloy 718 UNS N07718

Inconel™ 718 Material Property Data Sheet

At BBI, we are capable of supplying Stud Bolt & Nuts in INCONEL® alloy 718 UNS N07718.

ASME SA453 GR 660 A/B/C/D

EBB specializes in the supply of stud bolts and nuts manufactured to ASTM A453 Grade 660 (Alloy 286 / EN 1.4980). This material is a precipitation-hardened, heat-resistant steel that delivers exceptionally high mechanical strength and excellent corrosion resistance at temperatures up to 700°C. It is widely recommended for critical high-temperature applications such as jet engines, gears, turbines, paddles, spring washers, nuts, bolts, and other components requiring extreme heat resistance.

ASTM A453 Grade 660 (ASTM A286 Grade 660) offers outstanding corrosion resistance up to 700°C. Its oxidation resistance extends up to 800°C under continuous service conditions and up to 980°C under intermittent service conditions, making it ideal for severe high-temperature operating environments.

Duplex ASTM A182 F55

EBB manufactures SUPER DUPLEX fasteners in ASTM A182 F55, UNS S32760, and EN 1.4501, including screws, stud bolts, and nuts. This dual-phase (austenitic–ferritic) stainless steel is alloyed with chromium, nickel, molybdenum, and nitrogen, providing exceptional resistance to pitting, crevice corrosion, and stress-corrosion cracking.

ASTM A182 F55 offers an excellent combination of high mechanical strength and superior corrosion resistance, making it ideal for use in pressure-containing parts, pumps, valves, and centrifugal pumps operating under severe corrosive conditions.

Among chromium–nickel austenitic-type steels, ASTM A182 F55 is one of the highest-performing materials, especially in chloride-rich environments. Its corrosion resistance performs best in a fully solution-treated condition; therefore, we recommend limiting service temperatures to a maximum of 300°C to preserve its optimal properties.