Since the railroad’s genesis in the 1830s, there has always been a type of fastener that has held the rail firmly onto the tie plate, preventing the motion known as lateral movement, which is when an object, in this case the rail, moves from side-to-side, therefore, bringing the track out of gauge.
What are railroad tracks made of? Railroad tracks are made of rails, spikes, and railroad ties. Each component contributes to the vital infrastructure, ensuring rails remain in place, ensuring any lateral motion is prevented.
History
A fastener of a sort has been commonplace on the rails since the early 19th century. During the primitive days of the railroad, wooden rails were commonplace, thus, wooden pegs or nails would oftentimes be seen holding rails in place. These types of rails were commonly utilized in mines or on other early horse drawn railways. Iron plate-ways were also commonplace on many early mine railways, as they were inexpensive to construct, and horses could easily haul carts to the canals.
As the early railways continued to evolve iron rail containing flanges became commonplace, and utilized and sat on a “chair”, holding the rail in place. Some of the most popular type of rail during the late 18th and early 19th century was “fishbelly” rail, which was quite revolutionary at the time.
Various innovations in fastener technology were introduced in the following years, such as the “T” rail, which was bolted directly to the sleeper, and later bolted to a tie plate, which is common practice in the modern day. In addition to spikes, tie clips have become commonplace on various high speed rail lines, such as France’s TGV system.
In many instances, spikes have been utilized to mark momentous occasions, such as the competition of a revolutionary rail entity. The most prominent use of spikes in this manner was the completion of the transcontinental railroad in 1869, where Leland Stanford drove a golden spike into the tie plate to complete the line.
Throughout the years of innovation in railroad technology and infrastructure, the manner in which rails were fastened to the sleepers evolved into the infrastructure of the modern day. Invented by Camden & Amboy president John Stevens, the spike was designed with an offset head, which is meant to secure the rail, and prevent any lateral movement or shifting, especially under the weight of a train.
The technology of the railroad spike was primarily utilized in the United States in the 19th century, as other countries preferred the use of iron chair to secure rails. Iron chairs proved expensive and were relatively heavy however, and eventually were phased out in favor of spikes. The size of spikes vary, however, the most common types of spikes are between 9/16 to 10/16 in width, and 5 1/2 to 6 inches long.
Interestingly, although the spike is utilized to keep the rail in gauge, it is designed to leave some movement, as the spike is not implemented as firmly to the sleeper as the tie plate, due to not needing to support the rail vertically.
Rails
Rails are the component of track in which the train’s wheels make contact. Rails are oftentimes rolled steel shaped like an “I” beam, and are composed of a combination of carbon and manganese. Oftentimes, the percent of carbon within the rail is 0.7%, while the amount of manganese is 1%.
Rails have been constructed of many materials throughout the evolution of rail travel. In the late 18th century, rails were constructed utilizing wood, as many railways utilized horses for motive power. However, when locomotives were introduced, the wooden rails broke under their weight, and cast iron rails were introduced. However, as locomotive technology progressed during the 19th century, heavier and more powerful locomotives were built, and the cast iron rails were soon replaced with stronger wrought iron rails.
In early to mid 19th century, “T” style steel rails became commonplace, and have become the standard worldwide. Steel rails are ideal for the modern rail industry, as they are increasingly stronger than iron rails, and can handle the immense weight of modern trains.
Spikes or Fasteners
The railroad spike has evolved since the early days of the railroad in order to keep the track in gauge and prevent lateral motion. These implications were paramount when planning the construction of either a new railroad, or maintaining an existing right of way. Spikes became commonplace in North America in the 19th century, and spread throughout the world as the standard for railroad construction.
Different Types of Spikes
Dog Spikes
Dog spikes are similar to conventional railroad spikes, however, they are equipped with two lugs on either side, along with the longer end that holds the rail in place. These three pieces jut out of the spike head, resembling the ears and mouth of a dog, constituting its name.
Chair Screws
Chair screws are utilized to secure an iron chair to either directly to the sleeper, or a tie plate, usually utilized for bullhead rail, commonly utilized in Britain in the 19th century, or for securing a tie plate onto a sleeper for conventional flat bottom rail.
Spring Spikes
Spring spikes are a unique way of fastening rails in place, as they have a unique design, and shares little commonality with other forms of fasteners. These types of spikes are utilized to fasten flat bottom rail in place.
Fish Plates
Fish plates hold a vital role in the construction of railroads, as they hold the track together. When the ends of two pieces of rail meet, a fish plate is placed on both sides of the rail, with bolts on either side, bolting the two rails together. This has been replaced on many main lines, by continuous welded rail, which is much smoother, and can accept high speeds. However, fish plates remain in use periodically so the rail is able to flex under extreme heat or cold.
Installing Spikes and Fasteners
In the early days of rail transportation, constructing a section of track was long, tedious, and grueling work, as many railroad workers quit shortly after being hired on as a member of a track gang. During this time, spikes were driven into the tie plate manually with an pick ax, and took quite a toll on the worker’s physical well-being.
However, in the modern era, various machines have been implemented to perform the work that was done by pure manpower years prior. There are various machines that both install and remove spikes, completing work in a much quicker manner, while making life easier for various track workers.
These machines, called spike driving machines, drive the spikes into the tie plate and sleeper with ease, negating the need to perform these tasks manually. Machines not only make it easier for the workers, it increases the speed in which projects are completed, and increases the overall quality of the right of way. There are various spike driving machines consisting of different sizes, and perform the task previously carried out by a gang of workers. In addition to the installation of spikes, there are machines that remove spikes as well, further speeding up the process of maintenance work and construction.
Clips
With the genesis of high speed rail throughout the later half of the 20th century, standard rail fastening systems such as spikes proved to be insufficient to adapt to the high speed of the trains, and did not fuse well with the new addition of concrete sleepers. Thus, clips and other fastening devices were implemented to ensure the track structure could withstand the rapid velocity of the train.
Common types utilized are Pandrol Clips or fasteners, that is similar in shape to a paperclip, and securely hold the rail in place, and protects against lateral movements.
Tie Plates and Chairs
There are various forms of mechanisms to hold rail in place, and chairs and tie plates are some of the most common types of rail fasteners. Interestingly, chairs do not require the addition of additional spikes after installation, as the rail rests in the “U” shape of the chair, preventing any lateral motion.
Tie plates, utilized on flat bottom rail, is a fastener that holds the rail in place, and works together with the fasteners, such as spikes or clips, to keep the rail in the correct gauge. The rails are kept in gauge due to the shoulders, located on each end of the tie plate, in which the base of the rail fits tightly between in order to prevent movement. Tie plates have been commonplace since the very beginning of the twentieth century, as previously, the rails were connected directly to the tie plate.
Re-purposing Old Spikes
Interestingly, many old railroad spikes are oftentimes re-purposed as art pieces and home decor. Many utilize them as coat hooks, sculptures, and furniture. Additionally, many are often sought after by railroad enthusiasts as a collectors item.
Sleepers
Sleepers or railroad ties, are one of the most important parts of the railroad infrastructure. Ties have various critical implementations in the railroad infrastructure, as they play a crucial role in keeping the track in the correct gauge. Additionally, the assists in transferring the weight of a passing train to the ballast, and eventually, the sub grade.
Concrete
Throughout the years, ties have experienced various changes in technology, however, their basic duties have not been significantly altered. With the introduction of high speed rail throughout the world, concrete sleepers have been introduced, as they are more able to handle the speeds of these particular routes. Although concrete sleepers have become increasingly commonplace, wooden ties remain the standard for many railroads.
Concrete ties have many advantages, however, as they are more inexpensive to attain as compared to wooden ties. Additionally, concrete ties accrue less maintenance costs due to not needing to replace due to wood rotting and other traditional wear. When preparing to install track with concrete ties, the road bed, such as ballast and sub grade must be properly prepared, including proper drainage, and other precautions to ensure peak performance. One downside to concrete ties is they are exponentially more noisy than wooden ties.
Wooden
Wooden ties have been the standard since the genesis of rail travel, as timber was a resource that was readily available. In order to prolong their usage on a rail line, the ties are oftentimes treated with chemicals such as creosote, however, other chemicals could also be utilized.
Although wooden ties have been commonplace since the very beginning, they are prone to various natural effects, such as rotting, splitting, attacks from insects, such as termites. Additionally, wooden ties are susceptible to fire, especially when treated with chemical preservatives.
Metal Ties
Metal ties have been utilized on occasion throughout various different networks. Metal ties are oftentimes made from steel, and encompass a unique shape. The ends of the ties slope down and are shaped in a trough shape. These types of ties are commonly utilized on sidings, especially on secondary and branch lines. Steel ties are useful for sidings and low cost lines, as the ties utilize less ballast than conventional wooden or concrete ties, and have the ability to be installed over the existing ballast.
Although useful under some instances, older steel ties usually cannot take the weight of a train as well as other ties, thus, axle loading, train weight, and speed is strictly regulated, however, due to their stark durability, steel ties can last half a century!
However, after various years of experimentation and evolution of steel ties, they now have the ability to support heavier loads, and are a viable option in lieu of wooden ties. In addition to being utilized for main line stretches, steel ties have found a home on many turnouts and switches, as utilizing wooden ties requires the addition of a longer wooden tie on the turnout.
Related Questions
How much are railroad spikes worth? The value of railroad spikes varies, as oftentimes, price varies. Various resources list spikes as costing between .80 cents, to $1.30 per spike.
Which steel is used to make railway lines? Steel used on railway lines is carbon steel. In addition to carbon, manganese is often mixed with the carbon.
