fish plates and fish bolts
Fish plates and fish bolts are essential components in railway track construction and maintenance, serving as crucial connecting elements that join rail sections together. These components work in tandem to create a secure and continuous rail line. Fish plates, also known as joint bars, are metal plates that span the gap between two rail ends, while fish bolts are specially designed fasteners that secure the fish plates to the rails. The system typically consists of four to six bolts per joint, with two fish plates positioned on either side of the rail web. The plates feature carefully engineered dimensions and bolt holes that align perfectly with the rails, ensuring optimal load distribution and track stability. Modern fish plates are manufactured from high-grade steel, incorporating specific chemical compositions that enhance their durability and resistance to wear and tear. The design includes precise bolt hole spacing and plate thickness calculations to accommodate thermal expansion and contraction of rails while maintaining structural integrity. These components play a vital role in preventing vertical and lateral movement between rail sections, thereby ensuring smooth train passage and reducing maintenance requirements. The technology behind fish plates and fish bolts has evolved to include innovations such as improved surface treatments for corrosion resistance and enhanced bolt locking mechanisms to prevent loosening under vibration.