Function of rail fastening system
A rail fastening system is the whole set fasteners that are used to join the rails and railroad ties (or other type of rail foundation). Normally, rail fastening system is consist of rail spike, rail bolt, rail clip, tie plate, rail pad and plastic dowel, etc. Rail fastening system is also known as an intermediate coupling part. On the whole, railway fastening system plays a role in fixing rails to the sleepers, maintaining the gauge and preventing longitudinal and lateral movement of the rail relative to the sleeper.
History of rail fastening system
- In the earliest day, rail fastener means peg or nail that is used to fix wooden rail to wooden railway sleeper.
- By the 18th century, cast iron railways had put into application, which is easy to be fixed by the railway fasteners. At the same time, the first rail chair was applied in the railway in 1797.
- In the 1830s, the flanged' tee' rail was invented by Robert L. Stevens. This kind of rail is actually a distorted I beam, and it needn't a chair.
- Finally, flanged T railway become popular in the world, which require the rail fastening system to support.
Features of rail fastening system
According to the requirement of railway track transportation, rail fastening system should have the following characteristics:
- With sufficient strength and durability
- With adjustability of gauge and horizontal
- With good insulation properties
- With good damping elasticity
- With compatibility and interchangeability
Types of rail fastening system
For different applications, railway fastening system can be divided into various types. Each type of rail fastening system has its components, which is different with other types. Rail fastening system is typically named after the types of rail clip, such as skl rail fastening system, e-clip rail fastening system, kpo rail fastening system, nabla rail fastening system, etc.
SKL clip rail fastening system
Generally, the components of SKL rail fastening system include SKL tension clip, screw spike, flat washer, plastic dowel, guide plate and rail pad. Skl rail fastening system is used with concrete sleepers.
| Part Name | Type | Material | Surface | Remark |
| SKL tension clip | Dia. 13mm | 60Si2CrA, 38Si7 |
Plain oiled, color painting, or the other required ones. |
Hardness: 42-47HRC Fatigue test: When the clip spring deflection reaches 9.1mm and the swing deflection is 1.42mm, the fatigue life will be 5 millions cycles without breaking. Standard: DIN17221, GB/T1222 |
| screw spike | M24*150MM M24*160MM M24*180MM |
Grade 4.6: Q235 Grade 5.6: 35# Grade 8.8: 45# |
Plain oiled, black oxide, galvanized, hot dip galvanized, Dacromet and sherardized |
Standard: ISO898-1, UIC864-1 and NF F500-50 |
| plain washer | UIs7 | Q235 |
Plain oiled, black oxide, galvanized, hot dip galvanized, Dacromet and sherardized |
Standard: EN10025, EN10139 |
| plastic dowel | For different size of screw spike | HDPE, Reinforced Nylon 66 (PA66) | Black, blue, yellow, green or other color | For insert into concrete sleeper |
| guide plate | UIC54, UIC60, 50kg rail, 6kg rail, and other sizes as ordered | Reinforced Nylon 66 (PA66) | Black, blue, yellow, green or other color | Different designs are available. |
| rail pad | UIC54, UIC60 and sizes as ordered | EVA, or rubber | Black, blue, yellow, green or other color | Different designs are available. |
E-clip rail fastening
For E-clip fastening system, E-clip, shoulder, rail pad, insulator are necessary parts.
| Part Name | Type | Material | Surface | Remark |
| E clip |
Dia. 16mm Dia. 18mm Dia. 20mm |
60Si2MnA, 60Si2CrA,55SiMn |
Plain oiled, color painting, or the other custom finish. |
Hardness: 44-48HRC without breaking for Dia.18mm, 5 millions cycles without breaking for Dia.20mm GB/T1222 |
| Shoulder |
UIC54,UIC60, 115RE,50kg rail, 60kg rail,BS80lbs, BS100lbs |
QT500-7 QT450-10 |
Plain oiled, color painting |
Different designs are available. |
| Rail pad |
UIC54,UIC60, BS80lbs,BS100lbs, in ordered size |
HDPE, EVA, or rubber |
Black or other colors |
Different designs are available. |
| Insulator |
UIC54,UIC60, 50kg rail, 60kg rail, BS80lbs,BS100lbs, and size as ordered |
Reinforced Nylon 66 (PA66) |
Black, blue, yellow, green or other color | Different designs are available. |
KPO clip rail fastening system
KPO rail fastening system is usually consist of KPO clips, screw spikes, HS bolts, Hex nuts and double coil spring washer.
|
Part name |
Type |
Material |
Surface |
Remark |
|
KPO clip |
KPO3, KPO6, KPO9 |
Q235 |
Plain oiled |
Standard: DIN5906 |
|
HS bolt |
HS26, HS32 |
Grade4.6: Q235 |
Plain oiled, black oxide, galvanized, hot dip galvanized |
Diameter: 22mm or 24mm. |
|
Hex nut |
As ordered |
Grade 5: 35# |
Plain oiled, black oxide, galvanized, hot dip galvanized |
Standard: DIN985 |
|
Double coil spring washer |
As ordered |
65Mn |
Plain oiled, black oxide, galvanized, hot dip galvanized |
Standard: UIC864-3 |
|
screw spike |
M24×150mm |
Grade 4.6: Q235 |
Plain oiled, black oxide, galvanized, hot dip galvanized, Dacromet and sherardized. |
Standard: ISO898-1, UIC864-1 NF F500-50 |
|
Base plate |
UIC54,UIC60, 50kg rail, 60kg rail,S49 in ordered size |
Casting iron QT500-7, QT450-10, or forging low carbon steel or high carbon steel |
Plain oiled |
Standar |
Nabla clip rail fastening system
Structurally, a Nabla clip rail fastening system contains these parts like nabla clips, insulator, double end screw spike, special spring washer, hex nut and plain washer.
|
Part name |
Type |
Material |
Surface |
Remark |
|
Nabla clip |
Thickness 4mm or 4.5mm |
60Si2MnA, 60Si2CrA |
Plain oiled, red color painting, or the other required by customers |
Hardness: 42-47HRCFatigue without breaking GB/T1222 |
|
Insulator |
UIC54, UIC60, S49 rails |
Reinforced Nylon 66 (PA66) |
Black, blue, yellow, green or other colors |
Different designs are available. |
|
Double end screw spike |
UIC54, UIC60, 50kg rail, 60kg rail |
Grade 5.6: 35# |
Plain oiled, black oxide, galvanized, hot dip galvanized |
Bending at 30 degree without crack. |
|
Special spring washer |
18.25×34×78mm |
ML08Al |
Plain oiled, black oxide, galvanized, hot dip galvanized |
For protecting the thread of the double end screw spike |
|
Hex nut |
As ordered |
Grade 5: 35# |
Plain oiled, black oxide, galvanized, hot dip galvanized |
Standard: DIN985 |
|
Plain washer |
As ordered |
Q235 |
Plain oiled, black oxide, galvanized, hot dip galvanized |
Standard: DIN125 |
In conclusion, rail fastening system should be able to maintain the reliable connection between rail and railway sleeper effectively over a long period of time. Under the dynamic action, railway fastening system must give full play to its damping and the buffer performance. Besides typical types of railway fastening system mentioned above, there are many other kind of rail fastening system on the market, including high speed WJ series rail fastening system, type IV rail fastening system, fast clip rail fastening system and SFC fastening system etc.
