A drawbar is a type of hitch found on many farm or heavy construction implements. Manufactured of high-quality steel, a drawbar is almost unbreakable. Built to withstand great amounts of stress and resistance, this hitch is able to pull extremely heavy attachments such as plows and earth moving equipment with minimal risk of breaking.
The drawbar on a typical farm tractor is approximately 3 feet long (almost 1 meter), 4 inches wide (10 cm) and 2 inches thick (5 cm). This drawbar can weigh as much as 200 pounds (90 kg). This is due to the high quality of high carbon steel used in its manufacture. A drawbar on a locomotive can weigh thousands of pounds.
The drawbar is typically constructed with holes on each end. One end of the drawbar is attached to the vehicle with very strong bolts while the other is typically left open. A draw pin is inserted through the implements hitch and through the hole in the drawbar. The draw pin is also constructed of a very high quality steel that prevents it from bending, wearing through or breaking under the tremendous load.
Rarely, a drawbar will require changing. These are designed to last the lifetime of the vehicle that they are installed on. When a replacement is deemed necessary, the mounting bolts are also replaced with new ones. The incredible load that is placed upon these bolts dictates that they not be reused.
A drawbar is not cast from iron or steel, but rather forged from a block of billet steel. This type of steel is the strongest and most pure type of steel available. The quality of the steel allows it to ring like a bell when struck with a hammer. It also resists denting or nicking when struck repeatedly with a hammer.
The drawbar is heat treated to be harder anything that will be attached to it, as well as the draw pin which will be inserted through it. This prevents the drawbar hole from becoming oblong or worn out and the drawbar will not be worn through by the weight of the implement's tongue riding against its surface for long periods of time.
The drawbar is perhaps the strongest part of any machine that it is attached to. It is the most critical part in the completion of any type of job. If the drawbar fails, the job typically cannot be accomplished.