SKL Railway Fastener System is a key component for connecting rails and concrete sleepers. It is widely used in ballasted tracks around the world due to its simple structure, safety and reliability. Its specifications vary depending on the specific type and application scenario.
Common SKL Fastener System Types and Corresponding Specifications
SKL 3
This type of fastener system is suitable for a variety of rail types, such as UIC 54, UIC 60, 50kg/m, 60kg/m rails, etc. Its spring bar is usually 13mm in diameter. While ensuring the buckling pressure, it has a certain elasticity to buffer the impact force generated by the train operation. The common specification of spiral spikes is M24, with different lengths of 150mm, 160mm, 180mm, etc., which can be customized according to the thickness of the sleeper and actual installation requirements. The size of the matching plastic dowel is compatible with the selected spiral spike to ensure a stable installation. Rail pads have specific sizes for different rail types. For example, the pad sizes corresponding to UIC 54 and UIC 60 rails are specially designed to effectively disperse the pressure transmitted by the rails and enhance the overall stability of the fastening system.
| SKL3 Tension Clamp Specification | |
| Materials | 60Si2Cr, 55SiMn, 38Si7 |
| Hardness | HRC 42-47 |
| Fatigue life | 3-5 million cycles |
| Surface | Plain Oiled, Oxygen Black, Zinc Plated, Hot Dip Galvanized, Dacro |
| Spec | ø13 |
It is mostly used in ballastless tracks and belongs to a separate fastening system for sleeper track plates without concrete shoulders. Its main structural feature is that independent screw holes are set at both ends of the ribbed plate, which are connected to the railway sleepers or track plates through fork bolts. In terms of height adjustment, the height position of the rail can be adjusted by inserting the height setting plate to meet the track smoothness requirements. The dimensions and specifications of the components in the fastening system, such as spring bars, bolts, etc., are closely matched with the overall design of the system to ensure long-term stable operation in a ballastless track environment and withstand train loads.
| SKL12 tension clamp mechanical properties | |
| The tensile limit elasticity | >= 1150[MPa]. |
| The tensile strength | >= 1300[MPa]. |
| The elongation at fracture | >= 8%. |
| The surface hardness | ~400-460 HV 30 (In accordance with ISO6507 or equivalent). |
| Fatigue life | 3-5 million cycles |
SKL 14
Similar to SKL 3, it can adapt to a variety of rails. The spring bar is also 13mm in diameter, and the material is mostly 60Si2MnA, etc., to ensure good elasticity and fatigue life. It has been tested to withstand more than 5 million fatigue cycles without damage. The spiral spike specification is M24, with various lengths to adapt to different working conditions. The matching guide plates have specific models for UIC 54, UIC 60 and other rails. The rail pads also have different sizes and specifications according to the rail type and actual application scenarios, providing reliable support, insulation and buffering for the rails.
| Composition | Rail Tension Clip | Angled Guide Plate | Rail Pad | Screw spike | Flat washer | Plastic dowel |
| Type | SKL14 | Wfp14K-12 | As drawing | 24*161mm | As drawing | As drawing |
| Material | 60Si2CrA | PA66 | EVA | 35# steel | Q235 steel | PA66 |
| Weight (kg) | 0.495 | 0.17 | 0.17 | 0.635 | 0.048 | 0.072 |
| Requirement | HRC41-46 | black | 6mm | L=135mm |
Component materials and technical parameters and specifications
Spring clip
Common materials are spring steels such as 60Si2MnA and 60Si2CrA. After special heat treatment, the hardness reaches 42-47HRC, which makes it have high strength and good elastic recovery ability. In terms of buckling pressure, the buckling pressure design values of spring bars of different models of SKL fastener systems are different, but they can meet the fastening requirements of the corresponding line rails and effectively prevent the longitudinal and lateral displacement of the rails during train operation.
Spiral spikes
Generally made of 35# steel or 45# steel, with a performance grade of 5.6 or 8.8, in line with ISO 898-1 and other standards. The thread specification is unified as M24 to ensure the versatility and interchangeability with accessories such as nuts and washers. The length can be flexibly selected within the range of 150-180mm according to the type of sleeper and installation requirements to ensure that it can be firmly anchored in the sleeper and transmit the force of the fastener system.
Plastic dowel
Mostly made of reinforced nylon 66 (PA66), it has good insulation, wear resistance and anti-aging properties. Its size precisely matches the spiral spikes, plays a positioning and insulation role during the installation process, and prevents the current from being transmitted through the fastener system and affecting the normal operation of the track circuit.
Rail pad
The material is EVA (ethylene-vinyl acetate copolymer) or rubber, etc., with excellent elasticity and buffering properties. The pad size is customized according to the type of rail and the size of the sleeper bearing rail groove. The thickness is usually between 10-15mm, which can effectively disperse the concentrated force transmitted from the rail, reduce the stress on the sleeper surface, and extend the service life of the sleeper.
