A0 Railway Screw Spike

The A0 railway screw spike (also known as a sleeper screw, rail screw, a Tirafondos Tipo A0,or lag bolt) is a type of threaded metal fastener used to secure a rail base plate or rail directly to a railway sleeper (tie), primarily made from carbon steel. It offers greater holding power than traditional dog spikes. 

the A0 screw spike is designed for use in lower-speed tracks or light-duty applications, where the track conditions and load requirements are not as demanding as those in high-speed or heavy-duty rail systems.

Specifications and Standards

Usage and Features

• Function: Screw spikes are used to fasten steel track components to wooden or concrete sleepers, providing significant hold-down power compared to traditional cut spikes.

• Installation: They are screwed into pre-bored holes in the ties, sometimes used in conjunction with plastic dowels when used with concrete sleepers.

• Advantages: The main advantage of screw spikes is their greater fixing power, approximately double that of a common dog spike.

• Head Shape: The head is typically circular with a portion designed to receive a wrench for installation and removal.

• Disassembly: While they offer greater holding power, they are more difficult to disassemble and assemble compared to simple spikes, making track gauge adjustments more complex. 

• Versatility: The A0 railway screw spike is used in various rail systems, including heavy-duty tracks, mining lines, crane rail systems, and high-speed rail, depending on the specific grade and design.