How to weld a fish plate?

A rail fish plate is a steel joint bar designed to mechanically reconnect rail ends so that longitudinal continuity of the track can be maintained without welding. It allows jointed rails to collectively resist bending and shear forces generated by traffic loads. GNEE RAIL supplies fish plates for GB 8–60 kg/m rails, UIC50/UIC54/UIC60, DIN536 A55–A120 crane rails, QU70/80/100/120 crane rails, JIS rail profiles, AS1085 rails, BS11 sections, and AREMA/ASCE rail standards, with joint-system integration support.

The function of a rail joint bar

A rail joint bar (or fishplate) connects two rail ends to create a continuous, stable track, allowing for expansion and contraction due to temperature changes. By bolting onto the rail web, it maintains precise alignment, reduces wheel impact on the gap, and distributes heavy loads across the joint.

• Structural Connection: Links rail segments together, holding them securely in place.

• Load Distribution: Distributes the vertical and lateral loads of passing trains across the joints, minimizing stress on the rail ends.

• Alignment Maintenance: Ensures horizontal and vertical alignment between rails, preventing track sagging or misalignment.

• Thermal Management: Allows for safe expansion and contraction of rail lengths, preventing buckling or gaps.

• Electrical Insulation (Specific Types): Insulated joint bars prevent electrical current from flowing between rails for signaling systems.

How to weld a fish plate?

Welding a rail fish plate involves securing a steel plate over a rail joint to provide structural reinforcement, typically using arc, MIG, or thermit welding, often after cleaning, positioning, and clamping the plate. The process requires thorough cleaning of rust and contaminants, proper alignment, and often involves welding around the perimeter of the fish plate to ensure maximum strength.

Key Steps for Welding a Rail Fish Plate

• Preparation: Clean the rail surfaces thoroughly, removing all paint, grease, and rust using a grinder or wire brush to ensure a clean surface.

• Positioning: Place the fish plate over the rail joint. Ensure it is aligned correctly to provide maximum support to the weak point.

• Clamping: Secure the fish plate tightly to the rails using C-clamps or specialized rail clamps to prevent movement during the welding process.

• Welding Process: Use arc or MIG welding to join the plate to the rail, usually welding all around the perimeter of the plate.

• Final Inspection: Inspect the weld for cracks, porosity, or slag inclusions using visual or non-destructive methods like magnetic particle inspection.

What are the weight and length of the railroad joint?

Railroad joint bars (fishplates) typically weigh between 10--30 kg (22--66 lbs) per piece, with common 6-hole, 36-inch (approx. 914 mm) bars weighing roughly 25--27 kg (55--60 lbs). They are generally 24-inch (610 mm) for 4-bolt or 36-inch (914 mm) for 6-bolt configurations, tailored to rail size.

Key Specifications of Rail Joints:

• Weights: Common, rolled weights include 11.59 kg (SJ50), 14.50 kg (SJ60), and 17.36 kg (SJ57). Specific, heavier joints like 115RE (6-hole) can weigh 25.56 kg, while 132-136RE (6-hole) can reach 26.63 kg.

• Lengths: Standard lengths are typically 24 inches (609.6 mm) or 36 inches (914.4 mm). Some international standards include lengths such as 685.8 mm or 792.9 mm.

• Holes: Usually 4 or 6 bolt holes, with 6-hole bars used for larger, heavy-haul rail sections.

• Insulated Joint Weights: These are often lighter, with examples ranging from 0.81 kg to 5.54 kg depending on the model (e.g., 9KG to 30KG types).

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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