Vossloh rail clips are spring-steel tension clamp that hold rails firmly against concrete or wooden sleepers. Vossloh AG, the German railway infrastructure group, built its Fastening Systems division around the SKL (Spannklemme) platform. These clips are standard on high-speed lines across Europe and beyond. If you source, specify, or replace these fasteners, this guide covers the key details.
What Is a Vossloh Rail Clip?
The term “vossloh clip” refers to a screw-spike-and-tension-clamp assembly. A machine bolt pulls the clip toe down onto the rail foot, generating controlled clamping force. This differs from driven systems like Pandrol’s E-type. SKL stands for Spannklemme—German for tension clamp—and originates from Deutsche Bahn (DB) specifications. The vossloh rail clamp design suits heavy-axle freight routes as well as high-speed passenger lines.
Use our rail clips configurator to match clip type to your rail section quickly.
Vossloh SKL Rail Clip Models and Tension Clamp Systems
SKL 1 and SKL 12
SKL 1 and SKL 12 use a 13 mm spring-steel bar (38Si7 grade, 42–47 HRC). The toe force on SKL 1 is approximately 8.5 kN per clip. SKL 12 is the evolved version used on modernized concrete-sleeper track.
SKL 14
SKL 14 uses a thicker 14 mm bar in 60Si2MnA steel (44–48 HRC). Higher hardness delivers greater toe force, making it the preferred choice for high-speed and heavy-haul lines.
System W14, W21, and W30
The W-series tension clamps work with angled guide plates rather than vertical shoulders. They are lighter and faster to install than the SKL series.
| System | Bar Dia. | Hardness | Application |
|---|---|---|---|
| SKL 1 | 13 mm | 42–47 HRC | Standard track |
| SKL 14 | 14 mm | 44–48 HRC | High-speed / heavy haul |
| W14 | — | — | Angled guide plate |
| W21 | — | — | Angled guide plate |
| W30 | — | — | Heavy haul |
Exact W-series toe-force values: refer to the current Vossloh catalogue.
Vossloh Tension Clamps vs Other Clip Systems
Four clip families dominate the global market. Here is how the SKL compares:
- SKL / W-series (Vossloh): Screw-spike installation, adjustable toe force, suitable for concrete and timber sleepers
- Pandrol E-type: Driven into cast-iron shoulders, no bolt required, fast to install
- Nabla: Leaf-spring blade, common in Eastern Europe
- Deenik / South American types: Two-piece pressed-steel clip
SKL clips offer better lateral resistance than driven clips. However, they require a torque wrench and insulated washers. See the full overview of types of railway clips and their load profiles.
Matching Vossloh Rail Clips to Rail Section and Sleeper
Clip selection follows three steps:
- Rail foot width — determines shoulder spacing and base plate width
- Sleeper type — concrete monobloc, timber, or bi-block
- Axle load and speed — sets required toe force (kN) and lateral resistance
| Rail Type | Foot Width | Recommended System |
|---|---|---|
| UIC 60 | 150 mm | SKL 14 / W14 |
| 60 kg/m | 150 mm | SKL 14 / W21 |
| 115 RE | 146 mm | SKL 12 / W14 |
Full dimensional tables are available in our rail fastenings specifications and railway track clamps guides.
Vossloh-Compatible and Replacement Rail Clips
Sourcing vossloh compatible rail clips requires matching three parameters:
- Bar diameter: 13 mm (SKL 1/12) or 14 mm (SKL 14)
- Hardness: 42–48 HRC depending on grade
- Toe force: measured by a certified test rig per EN 13481
Steel grades 38Si7, 60Si2MnA, and 60Si2CrA all qualify. Surface treatment—hot-dip galvanizing or epoxy coating—must match the environmental exposure class. Vossloh replacement rail clips from Xingrail are dimensionally interchangeable and validated by hardness and toe-force batch testing.
For crane and industrial rail variants, see AREA railway standard track and DIN536 rail track.
Installation Notes
Tighten the machine bolt to the torque specified on the sleeper drawing—typically 200–250 N·m for concrete. Always fit the insulating pad and toe insulator before torquing. Check toe force periodically on high-cycle track. Thermal expansion can shift clips on long welded rail; re-torque after the first full temperature cycle.
Frequently Asked Questions
Q1: What is a Vossloh rail clip?
It is a spring-steel SKL tension clamp (Spannklemme) that presses down on the rail foot via a screw spike. Vossloh developed the system for Deutsche Bahn; it is now used on railways worldwide.
Q2: Which Vossloh clip models exist?
The main models are SKL 1, SKL 12, and SKL 14, plus the newer System W14, W21, and W30 tension clamps.
Q3: Are Vossloh clips compatible with other tension clamps?
Only dimensionally equivalent clips—matching bar diameter, shoulder spacing, and toe force—are interchangeable with the original design.
Q4: Can I replace Vossloh SKL clips with Xingrail clips?
Yes, provided bar diameter (13 or 14 mm), hardness (42–48 HRC), and toe force match the original specification.
Q5: How do I order vossloh-compatible rail clips in bulk?
Contact a vossloh rail clip supplier with your rail section, sleeper type, and required quantity. Xingrail provides test samples before bulk shipment.
