How To Choose The Right Kind Of Derail

Here are some guidelines to choosing a derail, but before purchasing be sure to check with your local railroad to be sure you are using the type appropriate for your track conditions.

Where to Install Derails

“ASK ALDON” Our sales engineers use aerial photos of your railyard to help you choose the best location for derail installation.
Contact us at [email protected] or 847.623.8800

1. Permanent vs. Portable

A permanent derail (hinged or retractable) gives you the convenience and security of a derail ready at all times to prevent unauthorized entry or car movement on your siding.

A portable derail gives you the flexibility of temporarily protecting any rail siding on your property.

2. Do you need 1-way or 2-way derail protection?

If your main concern is preventing unauthorized locomotive entry to your siding, choose a 1-way derail.

If you also need to prevent a rollaway car from leaving your siding, use a 2-way derail.

3. What size locomotives operate on your siding?

4-axle: choose 1-way or 2-way, any derail style

6-axle: choose 1-way derails, in any derail style. Use “low-angle” 2-way derails (the angle of deflection of the longer wheel base is too sharp for standard 2-ways) .. or, use two 1-ways back-to-back if traffic comes from two directions.

4. Type of rail and ties

If you have exposed rail built on wooden ties you can use any derail.

If your track is on steel ties, your choice of derail is limited to the hinged derail plus our steel tie adapter plate.

Do not use any hinged derails on track built with resin or concrete ties. A hinged or moveable wedge-type car stop may serve in place of a derail. Contact us for advice. Another alternative is to replace two of the resin or concrete ties with wooden ties.

Portable derails are for use on wood or full length pre-stressed concrete ties made to North American designs. Do not use on resin or steel ties.

Do not use derails on flush rail. The derailed wheels may not be able to sufficiently dig into the surrounding pavement to bring the car to a prompt stop. The alternative is to excavate the pavement in order install a hinged or moveable wedge-type car stop. Contact us for advice.

5. Rail Size

Portable derails fit all rail sizes, 90 lb. and up. Hinged and retractable derails are made in four standard sizes, each of which fits a small range of rails. Submit a sizing form when ordering hinged or retractable derails.

6. Direction of Throw

(Direction of throw is from the viewpoint of the oncoming locomotive or rail car.)