The WJ-8 railway fastener system plays a key role in the construction of high-speed railways. According to different standards, it can be classified into multiple categories, each with unique functions and application scenarios.
Classification by component function
Clipping parts
The spring bar is the core clipping component of the WJ-8 system, which is divided into W1 type and X2 type. The W1 type spring bar has a diameter of 14mm and a large clipping force. It is suitable for general areas and can provide a stable clipping force for the rails to ensure that the rails do not move under frequent train operation; the X2 type spring bar has a diameter of 13mm and a small clipping force. It is mainly used in special areas on bridges where small resistance fasteners are used. While meeting the stress requirements of the bridge structure, it ensures the stability of the rails.
Adjustment parts
The gauge baffle and gauge block undertake the important task of gauge adjustment. There are two types of gauge baffles: for general sections and for rail joints. The gauge baffles for general sections have eleven specifications from No. 2 to No. 12, and the gauge baffles for rail joints have eight specifications from No. 2 to No. 9. By replacing gauge baffles and gauge blocks of different specifications, the gauge can be adjusted continuously and steplessly, with an adjustment amount of about ±4mm, meeting the requirements for gauge accuracy during track laying and later maintenance. In addition, the under-rail fine-tuning pads and the iron pad lower height adjustment pads are used to adjust the height of the rails. The under-rail fine-tuning pads are divided into four specifications of 1mm, 2mm, 5mm and 8mm according to thickness, and the iron pad lower height adjustment pads are divided into two specifications of 10mm and 20mm according to thickness. Through different pad combinations, the precise adjustment of the track height can be achieved.
Connection and support parts
Spiral spikes, flat washers, iron pads and embedded sleeves constitute the connection and support structure of the system. Spiral spikes are divided into S2 and S3 types. S2 type is used for normal installation of fasteners or when the height adjustment of the rail does not exceed 15mm. S3 type is used for scenes with a height adjustment of more than 15mm. It passes through other components and is screwed into the embedded sleeve to tightly connect the components. Flat washers can increase the contact area to prevent loosening and wear of components. Iron pads connect and support other components, transferring the force from the rails to the concrete shoulder. Embedded sleeves provide a stable anchoring foundation for spiral spikes.
Insulation and elastic parts
Insulation gauge blocks are divided into Type I and Type II. Type I is used in general sections, and Type II is used at rail joints. Its main function is to ensure the insulation performance of the fastener system and prevent current leakage from affecting the track circuit. Rail pads include rubber pads and composite pads. Rubber pads are used in general sections and have good elasticity and vibration reduction performance. Composite pads are often used on bridges to optimize line resistance. The elastic pads under the iron pads are divided into two categories: A and B. Category A is used for passenger dedicated lines that also take freight into consideration, while Category B is used for passenger dedicated lines that only run passenger cars. This further improves the overall elasticity of the fastener system and absorbs vibration and impact from train operation.
