One of the most disregarded jobs in the field of welding right now is rail welding. Railways connect different parts of a country making it easier to transport goods and other important materials.
Being the 2nd most used way of transportation after airways, railroads need their specific maintenance throughout the year.
The type of process used depends upon the location and welders.
Specifically, Rail welding has 3 types of methods
- Puddle Arc Welding
- Exothermic Welding or Aluminothermic Welding or Thermit(e) Welding
- Flash Butt Welding
Each of these welding methods has its pros and cons. However, expertise over them gives you an edge if you are looking for rail welding jobs specifically.
Rail Welding Methods
Rail-welding is often overlooked, even though they serve as a backbone for the transportation network of a country.
The following are the methods used :
1 Exothermic Welding
Also known as the thermite welding or thermite rail welding, it is based on an exothermic reaction of thermite composition i.e a combination of iron oxide and alloys reacting with aluminum.
The heat released results in the melting of base metals, which is then joined permanently via molten steel as the filler. Before starting with the method, you should clean the ends of the rails.
Any form of debris or damaged rail end can cause inconsistency in the weld.
The rails are aligned and placed apart 25mm horizontally. When the heat released melts the rail ends, molten steel is poured into the welding mold as the filler material.
Remember to wear safety equipment while working with exothermic welding, as the released heat can cause critical injuries to you. Nowadays, due to the risk posed by exothermic welding, remote exothermic welding is used. They are similar to the working, the only difference being the distance between the arc and the welder.
Since no external power supply is required unlike the other two methods mentioned below, this is by far the most budget-friendly rail welding method.
Exothermic Welding is also marketed as Ultraweld, TerraWeld, Thermo Weld, etc across the world.
2 Electric Arc or Puddle Arc Welding
This is another form of welding which is popularly used for rail welds, utilizing electricity to generate heat to join metals.
Before getting into the process, make sure that the base metals are cleaned thoroughly. This ensures that there is a clean weld. Electrodes must be cleaned as well since any presence of moisture can cause critical harm to the material including brittleness.
The rail ends are pre heated and placed 20mm apart from each other, AC(Alternating Current) or DC(Direct Current) power supply is used to create an enclosed electric arc between the electrodes. This results in the melting of metals at the contact point of the electrodes.
Usually done manually, puddle arc welding got its name from the enclosed arc formed via the electrodes.
Wearing safety equipment must be your number one priority when working with this method, as it involves high amperage electric current flowing. Any form of technical difficulties might be lethal.
3 Flash Butt Welding
One of the most popular methods used in rail welding be it railroads or crane rails, which does not use any filler material is the flash butt welding.
This method is widely used across all the manufacturing industries, as filler materials are not required reducing the cost to a large extent.
Similar to the electric arc welding, Flash butt welding also utilizes electricity to join the metals permanently. In rail welding, the rail ends are placed at a fixed distance from each other, this distance is calculated based on the compositions and thickness of the rail.
Crane rails are mainly welded using the method of flash butt welding. Since there is no filler material required in flash butt welding, the weld is rather smooth compared to other methods.
Smooth weld otherwise makes sure that there are no gaps in between the connecting rail ends. Minimizing the cost of maintenance of the crane rails.
Rail Welding Apprenticeships
Rail welding is a major field of welding where mechanical work is preferred over automated industrial works.
This opens up a lot of opportunities for students who are still in welding schools or graduates who are finding jobs with their welding certificates in hand.
Apprenticeships have a lot to offer for new welders as they give you practical knowledge related to the industry.
At the same time, you are supported by other colleagues, they will guide and correct you if you are doing something wrong.
If you have found some companies that you want to apply for rail welding apprenticeships already, it’s your high time now. Try to contact them via LinkedIn, Twitter, etc.
If you are not sure where to get a rail welding apprenticeship, your best bet will be to look out for new opportunities.
Newspapers are a major source for these, also social media is booming. You can try to get in touch with supervisors or the regional head of a company and ask them for an apprenticeship directly.
Many rail welding company websites come with a link to apply for apprenticeships and jobs, However, it depends upon your knowledge and skills whether they will take you or not.
Keep in mind that, with rail welding you should be ready to work out in the open. Some may find it difficult to weld with sun right above their head without welding umbrellas or some other add-ons.
Rail Welding Machine
With a rail welding machine, you can either weld railroads or crane rails. Both of them utilize the same welding machine and have a similar weld pattern.
There are many different types of rail welding machines such as mobile rail welding trucks, narrow head welder, mobile flash butt weld machine, etc. These are very expensive and tend to work for long hours continuously.
For railroads, thermite welding is preferred over the other two as it does not require any external power source and heavy machinery.
To maintain the smoothness of the weld and the process, Thermite rail welding kits are used. It consists of the sand mold, An ignitor, Luting sand, crucible, and welding portion.
I concisely tried to explain how rail welding works, the methods used, and other related information via this article.
Rail welders have a difficult time schedule and sometimes due to emergencies they have to get to work regardless of the wet weather or storms.