In industrial piping systems, pressure equipment and offshore structures, corrosion resistant fasteners with high mechanical strength are generally chosen. Oil and gas, desalination and marine engineering industries are some of the fields that require duplex stainless steels as these steels are more resistant to chloride stress corrosion cracking than normal austenitic stainless steel grades and they have higher yield strength at the same time. For example, in heat exchangers, structural skids, pump bases and pressure vessel assemblies, Duplex 2205 Bolts are a very frequent component.
UNS S32205 composition allows these to have a balanced ferritic-austenitic microstructure and have a PREN value which is suitable for harsh environments. Bolt producers often use bar stock in line with ASTM A182 or ASTM A479 standards manufacture these articles and then, machine them as per the dimensional standards of ASME B18. Generally, sizes range from M6 to M36 or 1/4" to 1-1/2" in UNC and metric threads and these fasteners have tensile strengths that are higher compared to those of 316 stainless steel fasteners. The engineering procurement units involved in building infrastructure or refineries in cities like Riyadh and Dammam will make use of industrial B2B platforms such as pipingmaterial.sa to find verified suppliers, check stock availability and get in touch with genuine buyers dealing in certified duplex fasteners that come with mill test reports and heat traceability.
When thread galling is a concern, high-alloy austenitic materials are also considered. Parts made of UNS S21800 are especially noted for their resistance to wear and anti-seizing properties which make them ideal for repeated tightening and removing of valves, pumps and rotating equipment. Therefore, many maintenance engineers, who are responsible for petrochemical plant operations near Jeddah, turn to Nitronic 60 Socket Head Cap Screws when they need socket-drive fasteners that will adequately perform under high torque loads, not causing thread damage even after several servicing cycles.