How are rails joined together?
Dec 31, 2025
Fishplate, also known as joint bar, rail splint,splice bar, angle bar and track splint, is a type of rail fastener used for connecting rails. It plays a connecting role at rail joints. It bears the huge impact force and friction force from train wheel sets, and evenly transmits these forces to the rails to ensure the smooth operation of the train.
How are rails joined together?
Rails are joined in two main ways: traditionally with bolted fishplates (joint bars) for shorter segments, allowing for thermal expansion, and more commonly now, by welding them into long, continuous welded rail (CWR) for smoother, faster speeds, using methods like thermit welding, which creates a seamless, strong bond.
1. Bolted Rail Joints (Fishplates)
- How it works: Fishplates (or joint bars) are flat steel plates with holes that fit over the ends of two rails. Fish bolts go through the plates and the rail ends, securing them together.
- Purpose: This method creates a small gap for rail ends to expand and contract with temperature changes, preventing buckling, and allows for easy replacement of rail sections.
- Components: Includes the fishplate, fish bolts, nuts, and often spring washers to prevent loosening.
2. Welded Joints (Continuous Welded Rail - CWR)
- How it works: Individual rail lengths (e.g., 25m, 100m) are welded end-to-end to form continuous stretches, eliminating gaps.
- Common Methods:
Thermit Welding: A chemical reaction creates molten iron that flows between the rail ends, fusing them together. It's popular for its simplicity and lack of external power need.
Flash-Butt Welding: Uses high electrical current and pressure to fuse the ends.
Gas-Pressure & Arc Welding: Other less common methods.
- Benefits: Creates a smoother ride, reduces wear, and minimizes maintenance by removing the "clickety-clack" of jointed track, ideal for high-speed lines.
GNEE RAIL supplies rail fishplates for light rail, heavy rail, and crane rail systems. Each model is manufactured to international railway standards and available in carbon steel, alloy steel, or customized materials to meet specific operational needs.
All fishplates undergo precision machining, heat treatment, and anti-corrosion surface processing, ensuring optimal clamping force, fatigue resistance, and long-term service life.
| Application | Fishplate Types |
|---|---|
| Rail Joints for Light Rail | 8kg, 9kg, 12kg, 15kg, 18kg, 22kg, 24kg and 30kg |
| Rail Joints for Heavy Rail | 38kg, 43kg, 50kg and 60kg |
| Rail Joints for Crane Rail | QU70, QU80, QU100 and QU120 |
| Rail Type | Standard Length (mm) | Width (mm) | Thickness (mm) | Hole Diameter (mm) | Hole Spacing (mm) | Bolt Size | Material Options | Surface Treatment |
|---|---|---|---|---|---|---|---|---|
| 43kg Rail Fishplate | 800 | 65 | 16 | 22 | 90/105 | M22 | Carbon Steel / Alloy Steel | Oiled / Galvanized / Painted |
| 50kg Rail Fishplate | 800 | 65 | 20 | 24 | 100/120 | M24 | Carbon Steel / Alloy Steel | Oiled / Galvanized / Painted |
| 60kg Rail Fishplate | 860 | 70 | 20 | 24 | 100/120 | M24 | Carbon Steel / Alloy Steel | Oiled / Galvanized / Painted |
| QU70 Crane Rail Fishplate | 760 | 70 | 20 | 24 | 90/105 | M24 | Carbon Steel / Alloy Steel | Oiled / Galvanized / Painted |
| QU80 Crane Rail Fishplate | 820 | 75 | 20 | 24 | 100/120 | M24 | Carbon Steel / Alloy Steel | Oiled / Galvanized / Painted |
| QU100 Crane Rail Fishplate | 950 | 80 | 22 | 26 | 105/125 | M27 | Carbon Steel / Alloy Steel | Oiled / Galvanized / Painted |
| QU120 Crane Rail Fishplate | 1050 | 85 | 26 | 26 | 110/130 | M27 | Carbon Steel / Alloy Steel | Oiled / Galvanized / Painted |
When it comes to sourcing railway fish plate, GNEE RAIL is always your reliable and trusted partner. Because we are:
- With over 60% market share in Chinese railway field for rail joints.
- A long-term supplier of CRCC for both domestic and overseas contracted rail projects in over 50 countries all over the world.
- Over 30 kinds of standard and non-standard fishplates can be customized for global buyers.
- Granted ISO9001-2000 certificate and with approved license from China's Railway Ministry to produce railway products.
- Consistent quality guaranteed by 16 strict quality testing steps.
