Why the Combination Is Needed
Rail anchors and spikes complement each other in the railway fastening system, working together to ensure the longitudinal stability of the rail and the overall structural integrity. When trains pass at high speed, the rails are subjected not only to vertical pressure but also to longitudinal displacement tendencies caused by braking, acceleration and temperature changes. If only ordinary spikes are used to secure the rails, prolonged operation can easily lead to loosening due to repeated vibrations, resulting in gauge variations and sleeper damage.
The Role of the Rail Anchor
The primary task of the rail anchor is to prevent rail creep. It tightly grips both sides of the rail foot, utilizing its own high-strength elasticity or bolt locking mechanism to form strong friction and reaction forces against the sleeper side, thereby holding the rail in its designated position. The anchor resists the longitudinal forces that would otherwise push the rail along the track, and it is the component that controls the rail position under braking and temperature changes.
The Role of the Spike
The spike is responsible for reliably connecting the rail to the sleeper and the rail tie plate, ensuring vertical and lateral stability of the rail. The spike holds the rail down against uplift and prevents lateral movement, and its holding power maintains the gauge and the track geometry. The spike is driven or screwed into the sleeper, and its condition is maintained through the inspection program.
The Dual Action
When combined, the rail anchor restricts the longitudinal movement of the rail, while the spike provides robust vertical holding force. This dual action of resisting longitudinal movement plus resisting uplift effectively maintains the gauge and track geometry. The anchors are typically placed immediately adjacent to the spikes to fully utilize the clamping force exerted by the spikes on the sleeper, thereby enhancing friction.
Specifications and Coordination
Rail anchors are available for 50 kg, 85 kg, 90/91 lb, 115RE, 136RE, UIC54 and UIC60 rails, in materials including 60Si2MnA, 45 steel and QT500-7 ductile iron. The surfaces include plain oiled, color painting, zinc painted or HDG. Dog spikes are available in sizes such as 5/8 by 6 inches, 9/16 by 5-1/2 inches and 1/2 by 3-1/2 inches, in A3, Q235, 45 and 55 steels. Components such as rail clips, rail pads, fishplates and screw spikes also work in coordination, forming a complete railway fastening system that further distributes train loads, reduces fatigue impact on the spikes caused by vibration, and consequently extends the service life of both the rail and the sleeper.
Frequently Asked Questions
What does the rail anchor do? It prevents rail creep by tightly gripping both sides of the rail foot and using its own high-strength elasticity or bolt locking mechanism to form strong friction against longitudinal forces.
What does the spike do? It reliably connects the rail to the sleeper and the rail tie plate, holding the rail down against uplift and providing vertical and lateral stability.
What is the dual action? The rail anchor restricts the longitudinal movement of the rail while the spike provides robust vertical holding force, maintaining the gauge and geometry of the track.
Why are anchors placed next to spikes? To utilize the clamping force of the spike on the sleeper and enhance the friction between the anchor and the rail foot for a stronger combined hold.
What rails do the anchors suit? 50 kg, 85 kg, 90/91 lb, 115RE, 136RE, UIC54 and UIC60 rails, in materials including 60Si2MnA, 45 steel and QT500-7 ductile iron.
