Screw Spike vs Dog Spike
Railroad spikes are a common type of rail fastener used to connect the steel rail and the railway sleeper. There are many types of spikes, including screw spikes and dog spikes. From the appearance point of view, the more prominent difference between the screw spike and the ordinary spike is that the surface of the spike has an obvious thread. A thread is a shape having a uniform spiral protrusion on a section of the outer or inner surface of the solid, and the threaded engagement gives the screw spike much higher holding power than a driven spike.
Main Screw Spike Categories
According to structural characteristics and uses, screw spikes can be divided into four categories. The Ss series sleeper screw includes types such as Ss1/130, Ss1/150, Ss2/180, Ss5/150, Ss6/150, Ss7/180, Ss8/140, and Ss8/150. The square head screw spike is produced to UIC, AREMA, DIN, or GB standards, or according to customer drawings and samples. The hexagon screw spike is available in sizes such as M22 by 145 mm, M22 by 155 mm, M22 by 165 mm, M22 by 185 mm, and M22 by 195 mm. The double-head screw spike is a two-end-head type used with elastic clip fastening systems, especially popular in Africa.
Square Head Screw Spike Specifications
The square head screw spike is available in the Ss series to UIC, DIN, BS, and ASTM standards, with grades 4.6, 4.8, 5.6, 8.8, 10.9, and 12.9. Raw materials include Q235, 35K, 45# steel, 40Mn2, and 20MnSi. Common sizes include M22 by 145 mm, M22 by 155 mm, M22 by 165 mm, M22 by 185 mm, and M22 by 195 mm, in materials such as 45# steel and Q235, with natural, zinc, paint, or oil finishes. Other sizes and materials are available according to customer requirements.
Materials and Grades
40Mn2 is a medium carbon alloy steel with manganese as the main alloying element, providing high strength and good hardenability after heat treatment, which suits grades 8.8 and above. 20MnSi is a low carbon manganese-silicon steel with good weldability and ductility for general fastening applications. The grade system follows ISO 898-1, where grade 10.9 provides a tensile strength of at least 1000 MPa and grade 12.9 at least 1220 MPa, with controlled elongation and hardness.
Application and Quality Notes
Square head screw spikes are driven with a square spanner into pre-drilled holes in wooden sleepers or into plastic dowels in concrete sleepers. The fastening must be tight enough to hold the rail without over-stressing the sleeper. Fasteners must be free of cracks, folds, and thread damage, and surface treatments are selected according to the climate of the line. Special requirements for dimensions or higher strength materials can be produced on request.
Frequently Asked Questions
What is the main difference between screw spikes and dog spikes? The screw spike has an obvious thread on the surface, which provides much higher holding power than a driven spike.
What sizes are common for square head screw spikes? Common sizes are M22 by 145 mm, 155 mm, 165 mm, 185 mm, and 195 mm.
What materials are used? Q235, 35K, 45# steel, 40Mn2, and 20MnSi are typical materials for square head screw spikes.
Which standards apply? UIC, DIN, BS, and ASTM standards apply, with mechanical grades to ISO 898-1.
What is the double-head screw spike used for? It is a two-end-head screw spike used with elastic clip fastening systems, especially in African markets.
