There are different types of stainless steel fasteners that provide different levels of corrosion resistance and strength. They are used in corrosive industrial and marine environments, equipment, construction and construction applications. These products are available in all stainless steel designs and are used to join other metals such as copper, aluminum, carbon steel and zinc.
The specifications for a particular fastener grade should be based on the required corrosion resistance, strength and material to be fastened. The fastener should have corrosion resistance comparable to or higher than the corrosion resistance of the metal to be fastened. Specific application guidelines should be consulted to determine the most appropriate grade of stainless steel. SSINA Design Manual: Stainless Steel Fasteners can find general guidance. Some application-specific guidelines are provided in the Additional Design and Specification Resources section.
Stainless steel fasteners can be manufactured by machining or cold heading. Machining is the oldest method of producing fasteners, and it still stipulates very large diameters and small production runs.
Cold heading is a more common method of production. It transforms the wire into the desired shape by applying sufficient pressure to plastically deform the metal into the mold and stamping cavity without preheating the material. The production of bolts, screws, nails and rivets is relatively cool, but special custom operations can also be carried out in this way. Cold heading can significantly increase the strength of 300 series stainless steel fasteners.
ASTM International Standards for fastener materials and specific products (bolts, nuts, screws and bolts) are shown in the table below. There are general purpose and specialized standards for high temperature, high pressure and low temperature applications. It should be noted that stainless steel gaskets do not have ASTM standards.
|A 193 / A 193 M||alloy steel and stainless steel bolt material for special applications such as high temperature or high pressure service|
|A 194 / A 194M||Carbon steel and alloy steel nuts (including stainless steel) for high or high temperature service or both bolts|
|A774 / A774M||austenitic stainless steel joint (welded) for general corrosive service at low/medium temperatures|
|A951 / A951M||Standard Specification for Wire and Stone Reinforcement|
|A 962 / A 962M||fastener or fastener material or both are common requirements for any temperature from low temperature to creep range|
|A1082 / A1082M||Standard Specification for High Strength Precipitation Hardening and Duplex Stainless Steel Bolts for Special Applications, Note: For all high strength duplex and PH stainless steel fasteners – any size|
|C1242||Standard Guide for Design, Selection and Installation of External Size Stone Anchors and Anchoring Systems NOTE: This means that the metal in contact with the stone should be 300 series stainless steel, but other materials may be used if moisture and plating corrosion are properly prevented. Copper and stainless steel are used for the cable tie. Specify 316 instead of 304 if there is a typical coastal or deicing salt exposure. In harsh high salt environments, it is recommended to use more corrosion resistant stainless steel.|
|F 593||stainless steel bolts, hex screws and studs|
|F 594||Stainless Steel Nut Specifications|
|F 738M||stainless steel metric bolts, screws and studs, metric|
|F 788 / F 788M||Surface discontinuities in bolts, screws and studs, inch and metric|
|F 836M||Stainless Steel Metric Nut Specifications|
|F 837 / 837M||Stainless Steel Hexagon Head Screw Specifications|
|F 879 / 879M||stainless steel socket button and flat head skull head screw|
|F 880 / 880M||Stainless Steel Socket Set Screw Specifications|
Source: China Stainless Steel Pipelines Manufacturer – Yaang Pipe Industry Co., Limited (www.yaang.com)