Dog Spike vs Screw Spike: Key Differences and How to Choose
Sep 30, 2025
The railroad spike plays an important role in ensuring the stability of the track. It is a large rail nail used for fastening railway sleepers or rail ties to the rail. The obvious features of a track spike are the offset head and the flat-edge chisel point, which help the spike resist loosening. The rail spike is the main component of rail fastening on timber-sleeper tracks, and the same material can also be made into railroad spike knives for maintenance work.
According to their features, rail spikes are classified into two main types: screw spikes and dog spikes. They serve different functions and suit different track conditions. To satisfy the requirements of the environment, the service temperature and the fastening technology, special variants also exist, such as square-head spikes and hexagon-head dog spikes.
Structural differences
| Feature | Dog spike | Screw spike |
|---|---|---|
| Shank | Square or flat, no threads | Threaded like a screw |
| Head | Slightly cap-shaped dog head | Dome or countersunk head with driving recess or square drive |
| Installation | Hammered (driven) into the sleeper | Rotated (screwed) into the sleeper or sleeve |
| Holding principle | Friction between shank and timber plus head pressure on the tie plate | Thread engagement creates mechanical locking |
Fastening principle
Dog spike: relies mainly on the friction between the spike shank and the wooden sleeper, plus the pressure of the spike head on the tie plate, to hold the rail in place. The square shank resists rotation, and the offset head presses down on the rail foot or tie plate.
Screw spike: uses the thread to engage tightly with the wood, generating a mechanical locking force. The threaded connection gives stronger pull-out resistance and better vibration resistance than a friction-based dog spike, and the spike can be removed and re-driven several times without losing holding power.
Application scenarios
Dog spike: suitable for light-load, low-speed lines and wooden-sleeper tracks. It is easy to install, needs no pre-drilling on softwood sleepers, and is cost-effective. It is the traditional choice for branch lines, yards and secondary tracks.
Screw spike: suitable for medium-to-heavy-load railways, frequently used branch lines, and industrial tracks where higher stability and durability are required. Screw spikes are also used where the spike must be removable for rail renewal, and they are the standard for tracks with high vibration and lateral forces.
In short, dog spikes are traditional hammered-in spikes, while screw spikes are threaded, screwed-in spikes. Their fastening principles and performance differ, and they are not freely interchangeable in railway construction: replacing one with the other changes the holding force, the maintenance behavior and the sleeper life.
What to specify when ordering spikes
Give the rail section and sleeper type, the spike length and head form (dog spike or screw spike), the material grade (for example Q235, 45#, or spring-steel grades for special duty), the surface treatment (plain oiled, zinc plated, hot dip galvanized), and the property class for screw spikes (typically 4.6-10.9). For screw spikes used in concrete sleepers, specify the plastic dowel size as well.
FAQ
Which spike holds better: dog spike or screw spike?
Screw spikes hold better under pull-out and vibration, because the thread locks mechanically into the timber (or the plastic dowel in concrete sleepers). Dog spikes are adequate for light-duty timber tracks and win on installation speed and cost.
Can a dog spike be replaced with a screw spike in existing track?
Not directly - the hole geometry differs. A screw spike needs a pilot hole (and often a plastic dowel in concrete), while a dog spike is driven directly. Changing the spike type requires checking the sleeper, the tie plate holes and the fastening design.
Why is the dog spike shaped with a flat edge point?
The chisel-like flat point splits the wood fibers as the spike is driven, allowing the square shank to seat firmly and resist loosening from vibration. The offset head then presses on the rail foot or tie plate to hold the rail down.
Do screw spikes need pre-drilled holes?
On hardwood sleepers, yes - a pilot hole prevents splitting and lets the thread cut cleanly. On softwood, a pilot hole is still recommended for consistent seating. In concrete sleepers, the spike is screwed into a pre-cast plastic dowel.
What materials are railway spikes made from?
Commonly Q235 (low carbon), 35#/45#/55# (medium carbon) and alloy grades such as 40Mn2 and 20MnSi for higher strength. The material is selected by load, line type and environment; very high-carbon spikes are avoided where low-temperature toughness matters.
Can spikes be customized for non-standard projects?
Yes. GNEE RAILWAY RAILWAY supplies dog spikes, screw spikes and special head forms (square head, hexagon head) to drawings, including custom lengths, materials and surface treatments for railway, mining and industrial tracks.
