What is the gap between rail joints?

A rail fish plate is a precision-machined steel joint component that aligns rail heads and webs while allowing controlled longitudinal movement caused by temperature variation, balancing rigidity and expansion in jointed rail systems. GNEE RAILWAY RAILWAY produces fish plates for GB 8–60 kg/m rails, UIC50/54/60, DIN536 A55–A120, QU70–QU120 crane rails, JIS rails, AS1085 profiles, BS11 sections, and AREMA/ASCE rails, with export-ready packaging and logistics support.

What is the gap between rail joints?

Gaps between rail joints, often called expansion gaps or joint gaps, are typically a few millimeters (often up to 19 mm) left between rail ends to allow for thermal expansion and contraction, preventing tracks from buckling in heat or breaking in cold. These gaps are crucial for safety, managing structural stress, and are calculated based on rail length and temperature.

• Thermal Management: The primary function is allowing rails to expand in high temperatures and contract in low temperatures without warping or buckling the track.

• Safety Maintenance: Inspectors check these gaps to prevent derailments, ensuring they are not too small (causing compression/buckling) or too large.

• Preventing Structural Failure: Without proper gaps, rails can twist, bend, or become misaligned.

What is the function of a rail joint bar?

A rail joint bar (or fishplate) connects two rail ends to create a continuous, stable, and safe track, allowing for proper alignment and expansion/contraction. These essential, high-strength metal components ensure structural continuity, distribute wheel loads, minimize impact at joints, and prevent rail separation.

• Structural Connection: Joins the ends of two rails securely.

• Alignment Maintenance: Ensures smooth, aligned track surfaces, reducing vertical impact as wheels pass over the gap.

• Expansion/Contraction Control: Allows for the thermal expansion and contraction of rails to prevent bending or buckling, especially in summer.

• Load Distribution: Distributes the weight of trains across the joints to prevent damage to the rail ends.

• Stability & Safety: Provides a secure, rigid, and safe connection crucial for train operation.

Specifications of Rail fish plate

Rail fish plates (joint bars) are specialized steel components connecting rail ends to ensure structural continuity, manufactured in standard (4 or 6 holes) or custom configurations. They are produced from high-strength carbon steel (grades like 40#, 50#, K54/E54) via rolling or forging, adhering to UIC, BS, or AREMA standards, with tensile strength typically ranging from 550–650 MPa and elongation ≥ 18%.

Key Specifications of Rail Fish Plates:

• Standards & Grades: Common standards include UIC 864-4/864-8, BS 47-1, and AREMA 2007 (e.g., 115RE, 132RE). Material typically involves Chinese steel grade 40# or 50#.

• Rail Compatibility: Designed for specific rail profiles such as 60 kg/m, 50 kg/m, UIC54, UIC60, BS75R, BS80A, BS90A, BS100A, and BS113A.

• Hole Configuration: Light rails (≤ 30 kg/m) use 2-hole, while heavy rails (≥ 38 kg/m) usually feature 4 or 6-hole, bolted configurations.

• Mechanical Properties: High-strength, with tensile strength (Rm) typically 550–650 MPa, yielding strength, and 18% minimum elongation.

Founded in 2008, GNEE RAILWAY RAILWAY 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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