WJ-1/WJ-2 elastic clip rail fastener system

China WJ-1/WJ-2 Elastic Clip Rail Fastener System

Fastener Parts Mechanical Requirement:

•  Each set of fasteners buckle pressure ≥ 20 kN;
• The longitudinal resistance of rails for each set of fasteners shall not be less than 10 kN;
• The fastener system shall not be damaged after 3 million load cycles, and the gauge length shall be less than 6 mm;
• Adjusting the left and right position of the single rail: -6 to +4 mm, adjusting the gauge: -12 to +8mm; adjusting the height of the rail: -4 to +16 mm;
• System flexibility: static stiffness of the under-rail pad 50kN/mm;
• The pull-out force of the embedded iron seat is not less than 70 kN.

Type WJ-2 Elastic Clip Fastening System Introduction:

The WJ-2 type of spring rail fastener system is used for seamless tracked ballastless track fasteners, requiring a small longitudinal resistance of the line. It is a WJ-2 type elastic strip fastener system for the small-resistance of the ballastless track which is only used on the bridge in China. It is suitable for laying 60kg/m rail and concrete monolithic track bed on the standard gauge of the ballastless track on the bridge, meeting the high-speed railway.

The requirement for rail fasteners on the bridge to lay seamless lines. Under the rail and under the pad, there is a height-adjusting pad, the fastener has a gauge adjustment of +10mm to -12mm, and the rail height adjustment of +30mm to 0mm. The longitudinal resistance of each fastener rail is 6.5kN ± 0.5kN. If structural measures are taken, it can be reduced to 3.6kN ± 0.4kN, and the longitudinal resistance of the rail is lower than the normal fastener 7kN.

Applications of type WJ-2 Elastic Clip Fastening System

The WJ-2 type spring fasteners are designed according to the 60kg/m rail. They are suitable for the ballastless track structure on prestressed concrete beams that require high and low rails and large adjustment of left and right positions and lay long welded rails. They are also small resistance fasteners. It has been laid on the long-sleeve buried ballastless track structure of Qinshen Passenger Dedicated Line and has been tested by high-speed train with a speed of 321km/h.

Characteristics of Type WJ-2 Elastic Clip Fastening System

The structure of WJ-2 elastic clip fastener is similar to that of WJ-1 type shrapnel fastener, except that the elastic clip buckle is replaced with elastic strip fastener. The elastic strip design buckle pressure is 4kN and the front end elasticity is 11.5mm. The main design parameters and characteristics of the fasteners are as follows:

• The height of the fastener is 40mm. The height of the rail is adjusted by padding under the rail and under the iron pad into the height-adjusting pad. The adjustment amount is 10mm below the rail and 30mm under the iron pad.
• The left and right position adjustment of the fastener is ±10mm per track. The adjustment gauge is realized by moving the iron pad with the long round hole for continuous stepless adjustment.
• The fastener design can withstand a maximum lateral force of 50kN (fatigue load), and the concrete bearing platform does not have a shoulder.
• Set the 1:40 rail bottom slope on the iron pad.
• The fastener node stiffness is 40~60kN/mm.
• The nuts of fastener T-bolts are not arranged in an elastic manner. The tightness is required to make the fasteners evenly stressed. The nut torque of T-bolts is 90 to 100 Nm.
• Anchor bolt tightening torque is 300Nm.
• The embedded bushing has a pullout force of more than 100 kN.