A Metalworking Beginner's Guide to Rolling

Global steel output has expanded by more than 300% in the last 50 years, rising from 500 million tons in the 1960s to over 1,600 million tons in 2016. Of course, steel is only one of several metals manufactured and sold. Titanium, copper, brass, aluminum, and other metals are also used. While the particular technique used to manufacture these metals differs, many metalworking businesses employ rolling in their manufacturing.

What Is the Definition of Rolling in Metalworking?

Rolling is a metalworking shaping technique that involves passing molten metal through two or more rollers. A metalworking firm first warms the metal in a big furnace until it reaches a molten condition. Temperatures of 2,500 degrees Fahrenheit or more may be required, depending on the kind of metal. After the raw metal has been melted, it is passed through one or more rollers.

Why is metal rolled?

Rolling has various advantages, one of which is a thinner size. The molten metal is squeezed and becomes thinner as it passes through the rollers. For some applications, such as sheet metal fabrication, this is important to the completed product. The molten metal will be excessively thick for its intended use or application if it is not compacted.

Rolling, in addition to making metal thinner, promotes a more uniform shape. All rolled metal has the same form from top to bottom and edge to edge. As a result, metalworking businesses do not have to be concerned about some regions of the metal being thicker than others.

What Is the Difference Between Hot and Cold Rolling?

There are two types of rolling processes: hot and cold. When you hear the words "hot rolling" and "cold rolling," you might think the former involves passing molten metal through rollers and the latter involves putting cool or room-temperature metal through rollers. However, this is not always the case.

The steps for hot rolling are the same as those for cold rolling. Cold rolling, on the other hand, comprises the same processes as hot rolling but with an additional step at the conclusion. Cold rolling involves moving hot-rolled metal to a different forming station and rolling it again. However, this time it was rolled at room temperature.

Cold rolling affects the physical characteristics of metal because it compresses it when it is below its recrystallization temperature. Cold-rolled metal is often stronger and more capable of holding tighter tolerances than hot-rolled metal. The disadvantage, of course, is that cold rolling takes more time and resources than heat rolling.