Typical applications for screws and connecting elements made of A4 stainless steel are environments in close proximity to salt water.
A2 stainless steel screws are unsuitable owing to the high salt content of the water and air in these environments. A4 stainless steel is also used in the chemical and food industry because of its good acid resistance. V4A stainless steel is widely used in the pulp industry, because as an acid-resistant steel, it has been developed amongst other things for sulphuric acids in a boiling state. A4-alloyed fixtures are also replacing hot-dip galvanised fixtures on European motorways more and more. For example, many noise protection barriers and guardrail systems are now anchored to bridges using threaded rods/threaded elements made of A4 stainless steel. The bracketing systems of bridge drainage pipelines are also attached using A4. Further fields of application include the renovation of chimneys and certain areas of indoor swimming pools. However, stainless steel grades with a higher molybdenum content, such as special material 1.4529, still need to be used for safety-relevant components in indoor swimming pools that cannot be regularly cleaned or are constantly wetted with water.
