What is the fish bolt in railway track?

A rail fish plate is a fundamental joint component in non-welded rail systems, designed to maintain alignment, stiffness continuity, and load-sharing capability across rail ends under operational loads. GNEE RAIL supplies fish plates compatible with GB 8–60 kg/m rails, UIC rails, DIN536 A55–A120, QU70/80/100/120, JIS rail profiles, AS1085 rails, BS11 sections, and AREMA/ASCE rail standards, offering one-stop joint system solutions.

Components of a rail joint bar

A rail joint bar (or fishplate) is a metal bar used to connect rail ends, consisting primarily of two steel bars (inner and outer) that fit against the rail web, secured by four to six high-strength bolts, nuts, and spring washers. These components ensure structural integrity, allow for thermal expansion, and maintain alignment.

Key components and associated hardware include:

• Fishplates (Joint Bars): Two steel plates designed to match the rail profile, positioned on both sides of the rail web to provide support and strength.

• Fish Bolts (Rail Bolts): High-tensile bolts that pass through the holes in the joint bar and the rail web to secure the connection.

• Nuts: Threaded fasteners used to lock the fish bolts in place.

• Spring Washers: These maintain consistent tension on the bolt-nut assembly to prevent loosening caused by vibration and thermal expansion.

• Insulation Components (for Insulated Joints): In insulated rail joints, insulating plates, end posts, and washer bushings are used to prevent electrical continuity for signaling systems.

These components are typically made of high-strength steel, with some specialized joints using composite materials for insulation.

What is the fish bolt in railway track?What is its function?

A fish bolt is a high-strength, specialized fastener used in railway tracks to securely connect fish plates (joint bars) to the web of two abutting steel rails. Usually paired with nuts and washers, these bolts are essential for maintaining the structural integrity, alignment, and continuity of the track at joint locations.

Key Functions of Fish Bolts:

• Securing Rail Joints: They fasten fish plates to the rail web, preventing horizontal and vertical misalignment of the rail ends.

• Ensuring Structural Stability: They provide necessary clamping force to withstand heavy dynamic stresses and vibrations from passing trains.

• Maintaining Track Continuity: Fish bolts hold rail ends together, allowing the track to function as a continuous structure.

• Allowing for Expansion/Contraction: They are designed to allow small, controlled movements of the rails to accommodate thermal expansion, often featuring specialized, high-strength steel to prevent breaking.

These bolts are essential for safety and are used in various railway applications, including high-speed lines and heavy industrial tracks.

Specifications of Fish Bolts

Founded in 2008, GNEE RAIL is a leading global manufacturer and supplier of railway components, specializing in high-quality rail fish plates (joint bars/splice bars) with strong production capacity and global service capabilities.

Our rail fish plate portfolio is comprehensive and compliant with international standards including UIC, AREMA, BS, DIN, and GB, covering light rail (8kg-30kg), heavy rail (38kg-75kg), and crane rail (QU70-QU120) systems. We offer diverse types such as insulated joint bars, bulged fish plates, and compromise rail joints,with precise specifications (4-hole/6-hole, 24-inch/36-inch), ensuring excellent mechanical performance.We uphold strict quality control supported by ISO 9001:2015 certification, an in-house inspection center, and third-party audits by SGS and BV. Our one-stop service includes customization, production, packaging, and after-sales support, tailored to clients' project needs.

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