Carbon steel is manufactured as either sheets or coil by roller flattening it to the desired thickness whilst the steel is still hot, or after it has cooled.
Differences in the processes result in products that differ in terms of cost, quality and mechanical properties.
Hot rolled (HR) steel
HR steel is typically less expensive and produced in thicker gauges of 1.2 mm and upwards. HR and CR steel is the most likely to corrode and therefore the least expensive of the three metals most commonly perforated. Most grades can be protected against corrosion by post galvanising (dipping into hot zinc) or various painting treatments.
Cold Rolled (CR) steel
Cold rolled steel provides tighter tolerances and better surface finishes. While it can be produced in practically any gauge, it is most readily available in thinner gauges from 0.3 ĘC 3 mm. This material can be electro galvanised (ELO), post galvanised or painted after the perforation process to be protected against corrosion.
Hot Dip Galvanised Steel (HDG)
HDG products are often used for indoor and outdoor applications when protection against corrosion is required. For outdoor applications this material is often painted or powder coated. HDG flat products are available from 0.3 - 3 mm.