Rail joint bars, also called fishplates, connect the ends of two rails and transfer forces across the joint. Among the typical standards, such as AREMA, UIC, GB, and AS, the UIC standard is very popular in the railway market, especially the UIC54 and UIC60 rail joint bars. Although most rails are connected with joint bars, some tracks can also be joined by welding. Understanding the specification of the joint bar is essential for a reliable rail connection.
Drilling Patterns for Rail Joints
Usually, two or three holes are drilled in the end of each rail for the splices. The hole spacing pattern, also called the drilling, is measured from the end of the rail to the center of the first hole, and from the center of the first hole to the center of the second hole, and so on. Typical drillings are 2-1/2 inch by 5 inch or 3-1/2 inch by 6 inch by 6 inch, depending on the rail section and the fastening system used.
UIC54 and UIC60 Joint Bar Assembly
UIC54 and UIC60 rail joint bars are produced in 4 hole and 6 hole versions. The 6 hole bar is used at ordinary rail joints where higher longitudinal force transfer is needed, while the 4 hole bar suits lighter duty connections. The joint bar is clamped against the rail web by fish bolts, nuts, and washers, and the assembly is checked for squareness after tightening.
UIC54 and UIC60 Specifications
| Item | Spec | Material | Unit Weight | Surface | Packing |
| UIC54-6 hole | 920 mm long, 6 holes | 55 steel | 22.9 kg | Plain or black oil | Bundled on pallets |
| UIC54-4 hole | 630 mm long, 4 holes | 55 steel | 15.6 kg | Plain or black oil | Bundled on pallets |
| UIC60-6 hole | 6 holes | 55 steel | On request | Plain or black oil | Bundled on pallets |
| UIC60-4 hole | 4 holes | 55 steel | 17.5 kg | Plain or black oil | Bundled on pallets |
Other Typical Standards of Joint Bars
BS standard joint bars are produced for BS80A, BS80O, and BS90A rails in 4 hole and 6 hole versions, with unit weights from 6.7 kg to 13.32 kg in 45 steel or 55 steel. GB standard joint bars cover 43 kg, 50 kg, and 60 kg rails with 6 holes in 55 steel. AS standard joint bars are produced as NIJ-721 and NIJ-722 in 50 steel. All are supplied plain or black oiled and bundled on pallets.
Why Some Fishplates Have No Holes
Railway fishplates normally have four or six holes for the track bolts, but some fishplates have no holes at all. This is because, in some cases, the fishplates are welded directly to the rails to ensure the immobility of the connection. Removing the holes improves the convenience and quality of the welding, while the joint still transfers forces through the welded connection.
Manufacturing and Quality Assurance
Joint bars are manufactured according to the required international standard and the customer drawing, including the drilling pattern, length, and hole spacing. Production is controlled for material composition, dimensional accuracy, and mechanical properties such as tensile strength and cold bend performance. Custom standards including Chinese, South American, UIC, BS, DIN, and African standards can be produced according to drawings or samples, with an R&D center supporting new designs.
Frequently Asked Questions
What is a rail joint bar? rail joint bar, or fishplate, connects the ends of two rails and transfers forces across the joint with fish bolts.
Which UIC joint bars are most popular? UIC54 and UIC60 rail joint bars are the most popular in the railway market, in 4 hole and 6 hole versions.
What is the drilling pattern of a rail joint? The drilling is the hole spacing measured from the rail end to the first hole center and between hole centers, such as 2-1/2 by 5 inch or 3-1/2 by 6 by 6 inch.
Why do some fishplates have no holes? Fishplates without holes are designed to be welded directly to the rails, which improves welding convenience and joint immobility.
What material is used for UIC54 joint bars? UIC54 joint bars are typically made of 55 steel, with unit weights of 22.9 kg for the 920 mm 6 hole bar and 15.6 kg for the 630 mm 4 hole bar.
