E2091 Rail Elastic Clip: 20 mm Bar Clip Specifications and Use
Dec 03, 2025
Where the E2091 Sits in the E-Clip Family
An E2091 rail clip is a 20 mm bar elastic clip used to fasten rail to concrete or timber sleepers through a shoulder and a rail pad. The designation follows the same logic as the rest of the E-type range: the middle digits give the bar diameter and the final digits the body length class. Clips in this family are produced in bar diameters from about 18 mm to 23 mm, so the 2091 is the heavier, high-toe-load end of the range, while an 18 mm clip such as the E1813 is used where a lighter load is acceptable.
How the Clip Fastens the Track
The clip is installed between the rail foot and the shoulder. As it is driven home it bends, stores elastic energy, and presses the rail foot downward and outward simultaneously, which controls both vertical lift and lateral gauge spread. Because the load comes from bending rather than from a bolt, the clip is self-tensioning: it recovers its position as the rail moves and continues to apply force without any maintenance torque. The clip body also keeps a defined electrical path length, which matters where the sleeper is insulated for track circuits.
| Model | Bar diameter | Material | Clamping force | Hardness | Weight |
|---|---|---|---|---|---|
| E1609 | 16 mm | 60Si2MnA | ≥ 950 kgf | 44-48 HRC | 0.43 kg |
| E1809 | 20 mm | 60Si2MnA | ≥ 950 kgf | 44-48 HRC | 0.61 kg |
| E1813 | 18 mm | 60Si2MnA | ≥ 950 kgf | 44-48 HRC | 0.62 kg |
| E2055 | 20 mm | 60Si2MnA | ≥ 950 kgf | 44-48 HRC | 0.80 kg |
| E2091 | 20 mm | 60Si2MnA | ≥ 950 kgf | 44-48 HRC | 0.80 kg |
Material, Hardness and Fatigue Behaviour
E-type clips are forged from spring steel bar, most commonly 60Si2MnA to GB/T 1222, which offers the combination of yield strength and fatigue resistance that a bending spring needs. Hardness is normally specified in the 44-48 HRC band and checked with the Rockwell C method of ISO 6508-1. Service life is governed by fatigue at the bend radius and by corrosion, so the bar surface must be free of decarburisation and seams before forging, and protective coatings are applied after heat treatment. Complete fastening systems are qualified under EN 13481-2, which combines stiffness measurement, clamping force measurement and repeated-load testing on the full rail-shoulder-clip-pad assembly.
Installation Practice for 20 mm Clips
Twenty-millimetre clips develop a high toe load, so installation discipline matters more than for lighter clips. The shoulder must be cast or dowelled square to the sleeper, the pad must be the specified grade and thickness, and the clip must be driven fully home with the correct tool. A partly driven clip will still appear to hold the rail but will apply reduced force. On inspection, look for clips that have relaxed clear of the foot, cracks starting at the bend, bright wear marks on the shoulder seat, and rust staining that indicates a broken coating.
Typical Applications
Clips in this size class are used on ballasted mainline track, in turnouts and crossings, on bridges and in yards where lateral restraint is critical. They are also used where the track carries mixed traffic and the rail is expected to move slightly under repeated loads, because the elastic clamping action tolerates that movement better than a rigid fastening. Where insulation is required for signalling, an insulated shoulder, dowel or pad is used in combination with the clip rather than as a substitute for it.
Frequently Asked Questions
Q: What is an E2091 rail clip?
A: A 20 mm bar elastic clip of the E-type family used to fasten rail to sleepers through a shoulder, generating its clamping force by elastic bending.
Q: Which material is standard?
A: Forged spring steel, normally grade 60Si2MnA to GB/T 1222, tempered to a hardness of 44-48 HRC.
Q: What clamping force is specified?
A: Not less than 950 kgf at the working deflection, which is about 9.3 kN per clip.
Q: Can a 20 mm clip replace an 18 mm clip directly?
A: Only if the shoulder, pad thickness and drive tooling are correct for the heavier clip; mixing sizes on the same shoulder can alter the toe load and damage the seat.
Q: Do elastic clips need maintenance?
A: No torque maintenance is required, but clips should be inspected for relaxation, cracking and corrosion and replaced when the coating is broken or the clip no longer contacts the rail foot.
Q: How is the system qualified?
A: As a complete assembly under EN 13481-2, covering static stiffness, clamping force, electrical resistance and repeated-load fatigue performance.
