The Evolution of Train Sounds: From Jointed Rails to Welded Rails

Trains, a cornerstone of modern transportation, have undergone significant changes over the years, largely driven by technological advancements and regulatory requirements. Understanding the evolution of train sounds, especially the shift from jointed rail to welded rail, provides insights into these changes and the impact on the industry.

The Sounds of Modern Trains

In recent times, the sounds produced by modern trains, particularly diesel and electric locomotives, are quite different from their historical counterparts. Diesel engines produce a more consistent humming or rumbling noise, while electric trains are generally much quieter, producing minimal sound in comparison to steam locomotives. Advancements in technology and design have led to more efficient and quieter trains, reducing the iconic sounds associated with trains from earlier eras. Additionally, regulations in some regions have been implemented to minimize noise pollution, further altering the sounds trains make.

Nostalgia and the Sound of Steam Trains

Nostalgia for the sound of steam trains is not uncommon. Many heritage railways and tourist trains still operate vintage steam locomotives, allowing people to experience that classic sound. The distinctive chugging and hissing noises of steam locomotives can transport travelers to a bygone era, evoking a sense of wonder and excitement.

The Physics Behind Jointed Rail Sounds

The sound associated with jointed rail is a direct result of the gaps between the rails, which were necessary to accommodate expansion and contraction due to heat and cold. In the past, old lengths of rail were 39 feet long, fitting into 40-foot-long gondola cars. The gaps between these rail segments caused a characteristic sound, often described as a dum de dum dum noise.

The Transition to Welded Rail

While jointed rail systems were common and practical for many years, the move towards welded rail has significantly reduced or eliminated these characteristic sounds. Welded rail offers a continuous length of track, eliminating the gaps between segments. Although jointed rail is still used in some regions and on branch lines, the transition to welded rail has had a significant impact on the train soundscapes.

Even welded rail may have minimal gaps at each end of a quarter-mile length of rail, but these gaps are often mitigated by design features. For instance, some industrial switches incorporate a design where the flange rides on the rail of the other route, minimizing the gap on the mainline. This modern approach ensures a smoother ride and reduces maintenance issues associated with rail joints.

Benefits of Welded Rail

The removal of gaps in the rail has numerous benefits. Without the deteriorating ends at rail joints, regular replacement is less frequent, reducing maintenance costs. The smooth transition in welded rail also eliminates the jarring effect experienced by rolling stock, resulting in less wear on trucks and suspension equipment. These improvements not only enhance the riding experience but also contribute to a healthier, more sustainable railway infrastructure.

Modern Train Switch Design

Modern train switch designs are also evolving to incorporate these improvements. One example is the newer type of industrial track switch, where the diverging rail crosses an inch or so higher than the mainline, eliminating the gap on the mainline. This design, though not without its challenges, significantly reduces the dum de dum dum sound and provides a smoother riding experience.

Another example can be found at the Houston Amtrak station, where a segment of track was used for spotting private railcars. This design features a switch with very little gap, as the flange rides on the rail of the other route, further minimizing the characteristic sound.

Conclusion

The evolution of train sounds from jointed rail to welded rail represents a significant advancement in train technology. Its benefits extend beyond simply eliminating a historic noise, contributing to a more efficient, sustainable, and comfortable railway system. While the sound of steam trains remains a cherished memory for many, the modern railway industry continues to evolve, offering a better riding experience for all.