Product Description
IV fastener is a boltless shoulderless fastener for 60 kg/m rails. The elastic clamp IV type fastener system is designed to meet the operating conditions of passenger dedicated lines and is based on the line conditions of a ballasted track with prestressed concrete shoulderless sleepers.
Fastener: IV type elastic clamp fastener system is a fastener system for shoulderless track rails. The fastener system consists of C4 rail clamps (joint JA, JB spring clips), IV type embedded rail shoulders, insulating gauge blocks and rubber rail pads. The sleeper pads are located on prestressed concrete shoulderless sleepers. JA, JB clamps and joint insulating gauge blocks are used at rail joints.
Optimization and improvement:
The shoulderless bolt fastening system is based on the original type III fastening system after years of in-depth research and a large number of tests. The type IV elastic rail clamp fastening system has been optimized and improved in 4 aspects:
1) The structure of the elastic strip is further optimized, its working stress is reduced, and residual deformation is reduced;
2) The physical properties of the rubber pad adopt the UIC standard and meet international standards. ;
3) In order to achieve precise adjustment of the track gauge, the number of insulating track gauge blocks is configured at the 1 mm level;
4) Higher requirements are placed on the manufacturing acceptance of components.
Mechanical Properties
Buckling pressure of each set of fasteners ≥ 20 kN;
Longitudinal resistance of each fastener rail is greater than 9 kN;
The fastener system shall not be damaged under the following conditions: 3 million load cycles, the gauge length should be less than 6 mm;
The insulation resistance between the two rails is greater than 3 Ω·km, meeting the insulation resistance requirements of the track circuit;
System elasticity: The maximum bearing capacity of the static stiffness rubber pad is 60 kN/mm (±10 kN/mm)
After the 300 h salt spray test described in EN 13146-6, the fasteners can be removed with a manual removal tool;
Left and right position adjustment of single-line rails: -4 ~ +2 mm, gauge adjustment: -8 ~ +4 mm;
The pull-out force of the embedded iron seat should not be less than 60 kN.
Technical requirements for the support sleeper interface:
The technical requirements of the fastener system for the sleeper interface are mainly the type and size of the bearing groove and the embedded position and accuracy of the embedded iron pad in the sleeper, which matches the existing IIIb type buckleless prestressed concrete sleeper.
Comparison
Comparion of Elastic Clip Type IV and V Fastener System:
No. | project | Performance |
| | Elastic IV type fastener | Type V-Rail fastener |
1 | Adapt to rail type | China 60kg/m rail |
2 | gauge | 1435mm |
3 | Rail slope | A 1:40 rail bottom slope is placed on the sleeper. |
4 | Rail longitudinal resistance | Each set of fasteners is greater than 9kN. | In general, each set of fasteners is greater than 9kN; for
small resistance areas, each set of fasteners is approximately 4kN. |
5 | Systematic flexibility | The static stiffness of the under-rubber rubber pad is 60±10kN/mm; the dynamic-static stiffness ratio is not more than 2.0. |
6 | Fatigue performance | The fastener system is tested according to EN13146-4. After 3 million load cycles, all parts are not damaged, the gauge length is less than 6mm, and the buckle pressure, rail longitudinal resistance and node static stiffness meet the following requirements: buckle pressure change ≤ 20 %; Rail longitudinal resistance change ≤ 20%; node static stiffness change ≤ 25%. |
7 | Insulation resistance | The fastener system is tested according to EN13146-5. The insulation resistance between the two rails is greater than 3 Ω·km, and meets the requirements of the track circuit for its insulation resistance. |
8 | Harsh conditions Environmental
impact | The fastener system can be successfully disassembled with a manual disassembly tool after the 300h salt spray test described in EN13146-6. |
9 | Rail left and right position
adjustment | The left-right position adjustment amount of the single-
track rail is -4 to +2mm; the gauge adjustment amount is -8 to +4mm, and the adjustment level is 1mm. |
10 | Rail height
adjustment | Can’t adjust | Rail height adjustment position: 10mm; |
11 | Buckle pressure and range | The pressure of a single spring bar is not less than 11kN and the span is 13mm. | The commonly used elastic buckle pressure is greater than 10kN, the elastic range is 12mm; the small resistance elastic buckle pressure is 4.5kN, and the elastic range is 9.5mm. |
12 | Embedded part pull-out resistance | The pull-out force of the embedded iron seat in the sleeper is not less than 60kN. | The pull-out resistance of the embedded bushing in the sleeper is not less than 60kN. |
Features & Applications
Features and applications of type IV elastic rail clip fastener system.
Structural features of the type IV rail fastening system:
Like the type III elastic clamp fastener system, it is a boltless fastener system and an elastic non-detachable fastener without a concrete shoulder. It has the advantages of fewer parts, compact structure, high buckling pressure, strong track gauge capacity, and small maintenance workload. It is particularly suitable for railway lines with large-scale mechanical operations. Its main structural features are as follows:
a) Pre-embedded iron plate in concrete sleepers. The elastic clip is pressed into the rail by inserting the embedded iron seat, without bolts.
B) An insulating gauge block is installed between the embedded iron seat shoulder and the rail for gauge adjustment and insulation. By replacing different numbers of insulating gauge blocks, the left and right position of the rail can be adjusted.
c) The rubber pad between the rail and the concrete sleeper provides insulation buffering and damping.
d) The fastener system is used in conjunction with shoulderless prestressed concrete sleepers. The elastic clip type of the IV type fastener structure can be installed on the original IIIb type prestressed concrete sleeper.
Scope of application:
The IV type elastic clip system is suitable for laying 60 kg/m rails on high-speed railways, including:
1) High-speed railways with a rated speed of 350 km/h, equipped with mobile units (maximum axle weight of 170 kN);
2) High-speed railways with a speed rating of 250 km/h using mobile units (maximum axle weight of 170 kN), which can take into account a small number of ordinary passenger cars (maximum axle weight of locomotives 230 kN) and a small number of freight cars (maximum axle weight of 230 kN).
