Industry knowledge
The formation of cracks in railway fish plate is closely related to the interaction between the fishplate and the rail surface. The bolted fishplate and rail joint are not a rigid whole under actual working conditions. The impact of the wheels, the presence of rail gaps, and especially the decrease in tightening force caused by the wear between the rail and the fishplate will cause or aggravate the mutual rolling between the fishplate and the rail, resulting in surface deformation. The accumulation of this deformation provides a great opportunity for the initiation of cracks on the surface of the fishplate.
Specifically analyzing the friction pair of fishplate and rail, the most direct cause of the crack origin is the interaction between the contact surfaces of the two, such as the impact force of the joint, the vibration of the entire line, the wear caused by friction, the decrease in tightening force, the loosening of bolts, and all other factors that cause the interaction between the fishplate and the rail surface are conditions for micro-wear.
From a macroscopic point of view, the surface deformation and scratches caused by the rails can be seen on the damaged fishplate surface; from the fracture metallography, it can be observed that fine cracks have formed on the deformed and scratched surface and have developed in the depth direction; the phenomenon of the fishplate with cracks at the top is particularly obvious. In addition, the presence of a black oxidation zone in the origin of the macroscopic fracture crack also indicates that friction generates heat and oxidation when the cracks start.
All factors that intensify the interaction between the contact surface of the fishplate and the rail will cause cracks in the fishplate. The surface state of the fishplate and the rail, including the macroscopic and microscopic state, the size of the fastening force between the fishplate and the rail, the matching geometry, the wheel load and driving speed, and the basic condition of the joint are all factors that affect the cracks in the fishplate.
GNEE RAIL's railway fish plate products are exported to more than 160 countries and regions around the world, covering major railway construction markets in Asia, Africa, Europe, America, etc. We have rich export experience and mature customs declaration procedures, and can provide customers with fast, efficient and safe international transportation guarantees.
