The properties of the materials used in fasteners give them special characteristics. The requirements of the chemical and offshore industries place specific demands on fasteners, so the materials used in them must meet these requirements.
The use of fastening components in the chemical industry places special demands on screw fasteners. In machinery, equipment, tanks, valves, and other products, screw fasteners must withstand external stress as well as internal loads and forces. External stress factors, such as corrosive and rust-inducing chemicals, weaken the properties of screw fasteners. Depending on the chemical, the change can occur very quickly. The required special properties can be added to screw fasteners, for example, by adding alloying elements to the steel raw material before manufacturing, and by heat-treating or coating the fasteners with special substances after production so they can better withstand external stress.
The gas and fuel industry also places special demands on screw fasteners. Screw fasteners are typically used in machinery and equipment for processing these products, as well as in valves and piping, transport equipment, and transport vehicles such as forklifts, trucks, and ships. External conditions often vary from hot to cold and vice versa.
The table in the link lists special substances and their properties.