What device is used to test the strength of rail bonds?

The device that is used to test the strength of rail bonds is the bond tester. This specific tool is designed to measure the electrical resistance of the rail bond, which is essential for ensuring that the electrical connection between the rails and the bonding wires is strong and reliable. A weak or faulty bond can lead to electrical issues, which can affect signaling systems and the overall safety and functionality of the rail system.

In contrast, while a torque wrench is used to apply a specific amount of torque to fasteners, it is not suited for testing electrical connections. A pressure gauge measures the pressure of gases or liquids and does not apply to the testing of rail bonds. Lastly, a voltage meter is utilized to measure electrical voltage levels, rather than the integrity or strength of the bonds themselves. Therefore, the bond tester is uniquely equipped for assessing the performance of rail bonds, making it the correct choice for this task.