Chains are essential equipment for every respectable hip-hop artist. Without all that unnecessary amount of shiny metal and jewelry also known as “bling”, there is no other way to impress people and show all your haters out there that you have made it in life. However, the following article is not going to be about one of the most superficial cultural phenomenon in the history of humanity. Instead I am going about another type of chain that actually has a purpose and has proven to be quite useful throughout history and is still being used today. I’m am talking about the industrial chain.
Forged chain has been around for at least a thousand years and it was invented out of necessity. It was a tool in demand and it was mainly used with oxen or horses to pull farm wagons, logging sleighs, to anchor ships in harbors, for slings cranes and so on. The oldest and simplest type of chain is the coil chain. It is made from straight metal bars that are bent into an oval shape and then looped together and welded shut. Traditional chains were typically made from wrought iron, but nowadays, most people prefer chains made of steel.
When selecting an industrial chain there are basically three things that you need to consider and that’s grade, diameter, and coil. Of course, corrosion resistance is also an important concern which is determined by the finish.
The term grade refers to the strength of the metal. Manufacturers use grade numbers which are indicators of the ultimate break strength of the chain. A higher grade number means greater break strength. With galvanized chain, it all comes down to the amount of carbon in the steel. For example, grade 30 which is also known as proof coil, has less carbon and is ideal for service duty. A grade 40 on the other side has higher strength and higher abrasion resistance, but it also comes at a higher price.
The size of the chain links may also vary but the most common chains have and elongated link size which is also known as long link. This is one of the most practical choice because longer links mean that that shackles can fit anywhere along the chain, while with standard coil size you can only fit shackles at both ends.
As far as the finish is concerned, there are many options to choose from including galvanized, zinc, black plated, hardened, hardened boron alloy, and so on. A galvanized finish is produced by passing the chain through a bath of molten zinc. This gives the chain a dull gray look, but a fairly durable surface and resistant to corrosion. There is a similar process where a much thinner layer of zinc is applied, but it is far less durable and resistant to corrosion. Black plating is a process where a varnish with high bitumen content is applied to the chain and than baked at high temperatures. This option is popular for decorative reasons and provides protection against rust. Many types of steel are heat treated which increases the toughness and resistance and this process is known as hardening since in involves rabid heating and cooling.