Segment Connecting Bolts

The function of fastening parts for railway track fasteners

Rail fastener is a part on the track used to connect rail and sleeper (or other types of rail foundation), also known as intermediate coupling parts. Its function is to fix the rail on the sleeper, maintain the gauge and prevent the rail from moving vertically and horizontally relative to the sleeper. The rail fastening system is divided into spring fastener system, fastener plate fastener system and elastic strip fastener system.

Classification of fasteners and fasteners for railway track

1. Wooden sleeper fastener

A connecting part on a wooden sleeper track used to connect rails and wooden sleepers. According to the relationship between rail, pad and sleeper, it can be divided into two types: split lift type and hybrid type.

The separate type fastener is to separate the bolts or spikes that fix the rail and the iron base plate. Generally, the iron base plate is fixed on the sleeper with spike, and there is a rail bearing groove on the iron pad. The bolt fixing the rail is installed on the iron base plate, and then the steel rail is fixed with elastic strip or buckle plate.

The hybrid fastener is composed of iron plate and spike. The rail is directly connected with the iron pad and sleeper with the hook head spike (square). In order to prevent the rail from creeping longitudinally, more anti creeping devices are needed.

2. Concrete sleeper fastener

Connecting parts on concrete sleeper track used to connect rail and concrete sleeper. Due to the characteristics of heavy weight and high stiffness, concrete sleepers have higher requirements for fastener performance, and strict requirements for its buckle pressure, elasticity and adjustability. According to its structure, the fastener of concrete sleeper can be divided into three types: elastic strip fastener, buckle plate fastener and spring type fastener (refer to the fastener of concrete sleeper); according to the elasticity of fastener itself, it can be divided into rigid fastener and elastic fastener; according to whether the concrete sleeper has shoulder, it can be divided into two types, one with shoulder and the other without shoulder. In the early stage of China's concrete sleeper fastener, there are mainly two kinds of fastener plate type and spring plate type. Because of the low strength of arch spring piece, arch spring fastener is easy to cause residual deformation and even fracture, so it is no longer used in Chinese railway. Due to the lack of elasticity and low buckle pressure, the buckle plate fastener is easy to loose in the process of use. At present, it has been gradually replaced by elastic bar fastener in China Railway. The elastic strip fastener uses elastic strip as the fastener. It uses the bending deformation and torsion deformation of the material, and there is no problem of weakening the cross section. The structure is reasonable, so it has become the main type of fastener for concrete sleeper track in China. At present, the main type of fastener is elastic bar type I fastener. With the development of heavy haul high-speed railway, elastic bar type II and type III fastener have been developed successfully in recent years. Among them, type III fastener is bolt free and shoulder free.

3. Gusset fastener

The fastener plate type fastener is composed of gusset plate, screw spike, spring washer, iron seat and cushion plate. The screw spike is anchored in the reserved hole of concrete sleeper rail bearing platform with cement mortar, and then the gusset plate is fastened with bolts.