At Grafton Pipe Fittings, we specialize in manufacturing and supplying high-performance bolts that meet stringent global standards, including ASTM A193 Grade B7 and UNS K21590. Our bolts are engineered for durability, strength, and resistance to extreme temperatures and pressures, making them ideal for a wide range of industrial applications. These high-strength alloy steel fasteners are primarily used in pressure vessels, heat exchangers, valves, and flanges in petrochemical, oil & gas, and power generation industries.

The ASTM A193 Grade B7 standard governs the specifications for chromium-molybdenum alloy steel bolts intended for high-temperature service. The UNS K21590 material composition ensures superior mechanical performance, including high tensile strength and yield strength, excellent wear resistance, and long service life even in harsh environments. These fasteners are heat-treated and tempered to enhance performance under elevated conditions, which makes them a preferred choice in demanding applications.

Grafton Pipe Fittings offers a complete range of sizes and threading options, fully compliant with international standards such as DIN, ISO, BS, and ASME. Our bolts are available in both metric and imperial dimensions, with precision manufacturing that ensures exact tolerances, excellent surface finish, and dimensional accuracy. Each product is rigorously tested to comply with quality benchmarks and is accompanied by a certified Material Test Certificate (MTC) as per EN 10204 3.1.

The surface finishing options include plain, black oxide, hot-dip galvanized, and zinc plating, providing enhanced protection against corrosion and oxidation. Our bolts undergo thorough inspection and nondestructive testing (NDT), ensuring flawlessness in structure and integrity. This attention to quality ensures our bolts meet the expectations of critical infrastructure and mechanical assemblies where performance cannot be compromised.

Specification Of Bolts

World Wide Delivery