Installation of Rail Fish Plates: Best Practices
Installation Best Practices
Preparation of the Rails and Fish Plates
Before installation, it is crucial to ensure that the ends of the rails are clean, smooth, and free from any defects. Any rust, dirt, or debris on the rail ends can affect the proper seating of the fish plates and the effectiveness of the connection. The fish plates themselves should also be inspected for any signs of damage, such as cracks, dents, or warping. If any issues are detected, the fish plates should be repaired or replaced. In addition, the bolt - holes in both the rails and the fish plates should be checked to ensure they are aligned correctly and are of the proper size for the bolts that will be used.
Alignment and Fitting
When installing the fish plates, precise alignment is key. The fish plates should be placed symmetrically on both sides of the rail joint, with the holes in the fish plates aligning perfectly with the bolt - holes in the rails. Special alignment tools can be used to ensure that the rails are in a straight line and that the fish plates are fitted correctly. This is especially important in high - speed and heavy - haul railways, where even a slight misalignment can cause significant problems. Once the fish plates are in position, the bolts should be inserted through the holes. The bolts should be tightened gradually and evenly, following the recommended torque specifications. Over - tightening or under - tightening the bolts can lead to problems such as loosening of the connection over time or excessive stress on the fish plates and rails.
Use of Anti - Seize Compounds and Washers
To prevent the bolts from seizing due to rust or corrosion, anti - seize compounds can be applied to the threads of the bolts before installation. This makes it easier to remove the bolts during maintenance and reduces the risk of damage to the threads. Additionally, washers should be used under the bolt heads and nuts. Washers help in distributing the load more evenly, reducing the risk of the bolts pulling through the fish plates or the rails. Lock washers or other locking devices can also be used to prevent the bolts from loosening due to vibrations.
