Rail Fastening System

 

A rail fastening system (also referred to as a track fastening system or rail clip assembly) is a structural locking assembly that secures steel rails to underlying concrete sleepers (ties), wooden ties, steel sleepers, or ballastless slab tracks.

 

The primary operational purpose of a rail fastening system is to lock the rail in a fixed spatial orientation under dynamic axle loads, maintain precise track gauge width, and prevent longitudinal rail creeping or lateral displacement caused by dynamic train braking, accelerating forces, and thermal stress.

 

• Gauge Retention: Holds steel rails at a fixed width to prevent derailment risks.

 

• Load Distribution: Transmits dynamic vertical wheel loads and lateral thrusts evenly into sleepers and ballast.

 

• Vibration Damping: Resilient elastomeric pads attenuate high-frequency impacts and track vibration.

 

• Electrical Insulation: High-resistance polymer insulators prevent electrical signal leakage between rails and ground circuits.

 

 

Common types of rail fastening systems include E-Clip, SKL, KPO, Nabla, N-Type, Fist, elastic rail clip, direct-fixation, and embedded rail fastening systems. The appropriate system depends on the rail profile, sleeper or track structure, axle load, operating conditions, gauge adjustment requirements, and installation method.

 

 

Select the appropriate fastening assembly based on your track structure, rail profile, and operational parameters:

 

Fastening System	Compatible Rail Sections	Sleeper / Tie Type	Max Axle Load	Primary Application	Key Design Feature
SKL (Vossloh Type)	UIC54, UIC60, 60E1, 54E1, 115RE	Pre-stressed Concrete	25 - 35 Tonnes	High-Speed & Heavy-Haul	High fatigue strength, bolted clip assembly with plastic dowels
E-Clip System	UIC54, UIC60, 115RE, 136RE, 50kg	Concrete, Timber, Steel Ties	22 - 30 Tonnes	Mainlines, Turnouts, Industrial	Threadless, drive-on spring steel clip design
Fast Clip System	UIC60, 60E1, 136RE	Concrete Sleeper / Slab Track	25 - 35 Tonnes	High-Speed & Automated Track	Pre-assembled captive system for high-speed automated installation
KPO Clamp System	UIC54, UIC60, S49, Crane Rails (A75-A120)	Steel Sleepers, Wooden Ties	20 - 30 Tonnes	Crane Tracks, Port Terminals, Mining	Heavy-duty ribbed baseplate with flexible lateral gauge adjustment (+/-10mm)
Nabla System	UIC54, UIC60, S49	Concrete Sleeper / Slab Track	22 - 25 Tonnes	Urban Metro, LRT, Tunnels	Low profile, ultra-high lateral stiffness, trapezoidal blade design
Fist System	UIC54, UIC60, 50kg	Concrete Sleeper	26 - 32 Tonnes	Heavy-Haul Freight, Remote Lines	Pin-locked horseshoe clip, high resistance to vandalism and theft

 

 

The E-Clip rail fastening system is a threadless, drive-on elastic clip assembly engineered from high-strength spring steel (typically 60Si2Mn) designed to secure rails to wooden, concrete, or steel ties without requiring threaded bolts. Widely utilized across global ballasted mainlines, industrial sidings, and turnout switches, the E-clip delivers a constant, high-level toe load and strong torsional resistance through simple mechanical insertion, offering exceptional fatigue endurance, ease of maintenance, and reliable track gauge retention under dynamic dynamic axle loads.

 

 

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 Toe Load: 5.0-7.0 kN for Dia.16mm 7.5-9.0kgf for Dia.18mm 1100-1400kgf for Dia.20mm Fatigue life:3 millions cycles without breaking for Dia.18mm, 5 millions cycles without breaking for Dia.20mm Standard: DIN17221, BS970, 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.

 

 

The SKL (Vossloh) rail fastening system—frequently designated as a W-series tension clamp assembly—is a bolted elastic fastening mechanism engineered primarily for pre-stressed concrete sleepers on high-speed passenger lines and heavy-haul freight corridors. Utilizing spring steel SKL clips secured by high-tensile screw spikes anchored into embedded plastic sleeper dowels, this system provides high elastic deflection, maximum toe load retention, and outstanding fatigue resistance against high-frequency dynamic vibrations and severe dynamic stresses.

 

 

Part Name	Type	Material	Surface	Remark
SKL tension clip	Dia. 13mm-15mm	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.

 

 

The Fast Clip rail fastening system is a pre-assembled, threadless elastic clamping assembly designed for rapid, automated track construction and efficient maintenance on concrete sleepers or ballastless slab track structures. Featuring captive spring clips that remain pre-mounted within cast-in ductile iron shoulders during sleeper fabrication, the Fast Clip system enables fast, low-cost installation via mechanized clipping equipment, significantly reducing manual track-laying labor while maintaining consistent toe load, electrical insulation, and dynamic track stability.

 

 

Item	Components	Quantity/Set	Material
1	Fast Rail Clip	4	60Si2MnA
2	Insert Shoulder	4	QT450-10
3	Rail Insulator	4	PA66+30%GF
4	Rail Pad	2	Rubber & EVA & HDPE

 

 

The KPO Clamp rail fastening system is a heavy-duty, bolt-secured clamping assembly featuring a ribbed steel baseplate, rigid or semi-elastic KPO clamp plates, T-head bolts, and spring washers. Extensively applied on steel sleepers, wooden ties, crane rail runways, and port terminal logistics lines, the KPO system provides superior resistance against severe lateral thrusts and heavy vertical axle loads, while offering flexible lateral gauge adjustment capability (±10 mm) to accommodate structural wear and track alignment tolerances.

 

 

Part name	Type	Material	Surface	Remark
KPO clip	KPO3, KPO6, KPO9	Q235	Plain oiled	Standard: DIN5906
HS bolt	HS26, HS32	Grade4.6: Q235 Grade5.6: 35# Grade8.8: 45#	Plain oiled, black oxide, galvanized, hot dip galvanized	Diameter: 22mm or 24mm. Length: 55mm, 65mm, 75mm, 90mm Standard: UIC864-2
Hex nut	As ordered	Grade 5: 35# Grade 8: 45#	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 M24 ×160mm M24 ×180mm other length	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 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	Standard: UIC864-6

 

The N Type clip rail fastening system is a compact, trapezoidal elastic blade assembly designed to deliver high lateral stiffness and reliable clamping force on concrete sleepers or ballastless slab tracks. Securing the rail foot via high-tensile screw spikes passed through specialized spring blades and composite guide pads, the N Type system provides an ultra-low profile, high electrical insulation, and superior resistance to lateral displacement, making it a preferred solution for urban metro transit, light rail transit (LRT) networks, and space-constrained tunnel infrastructure.

 

 

Part name	Type	Material	Surface	Remark
N Type clip	Thickness 4mm or 4.5mm	60Si2MnA, 60Si2CrA	Plain oiled, red color painting, or the other required by customers	Hardness: 42-47HRCFatigue life: 3 millions cycles without breaking Standard: DIN17221, 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

 

The Fist rail fastening system is a heavy-duty, pin-locked elastic fastening assembly comprising a horseshoe-shaped spring steel clip and a trans-sleeper pin anchored through a pre-formed tubular hole in the concrete tie. Engineered for high resistance against vandalism, component theft, and severe dynamic impacts, the Fist system clamps both sides of the rail foot simultaneously with uniform pressure, delivering long-term gauge retention, high electrical insulation, and minimal maintenance overhead across heavy-haul freight lines and harsh remote operating environments.

 

 

 

A complete rail fastening system consists of six primary components: elastic spring clips (or tension clamps) that clamp the rail foot; cast-in shoulders that retain the clips; resilient elastomeric rail pads that absorb shock under the rail; polymer insulators that isolate electrical signaling currents; heavy ductile iron baseplates that distribute vertical axle loads; and high-tensile screw spikes fitted into plastic dowels that anchor the entire assembly to the sleeper.

 

 

A rail clip (also known as an elastic rail clip or tension clamp) is a high-strength spring steel fastener designed to exert a constant, high-level vertical down-force (toe load) onto the foot of the steel rail. Hot-formed from alloy spring steels such as 60Si2Mn or 55Si7, the rail clip mechanically locks the rail against lateral displacement and longitudinal creeping caused by heavy dynamic wheel traffic, thermal expansion, and train braking, while providing long-term fatigue endurance across millions of operational load cycles.

 

Surface treatments available in Plain Oiled, Black Oxide, Dacromet, or Custom Powder Coating (Red/Blue/Yellow for easy track inspection).

 

 

A rail spike is a heavy-duty metallic anchoring fastener used to secure steel rails or baseplates directly into wooden ties or concrete sleepers. Ranging from traditional square-shank cut spikes (dog spikes) used on timber tracks to high-tensile threaded screw spikes driven into plastic sleeper dowels, rail spikes absorb severe vertical uplift and lateral shear forces, maintaining solid mechanical attachment and track gauge stability throughout the sleeper bed.

 

A rail pad is a resilient elastomeric cushion positioned directly between the base of the steel rail and the underlying tie plate or concrete sleeper. Manufactured from high-density polyethylene (HDPE), ethylene vinyl acetate (EVA), polyurethane, or synthetic rubber, the rail pad dampens dynamic wheel impacts, attenuates high-frequency track vibrations, prevents metal-to-concrete surface abrasion, and distributes heavy vertical axle loads evenly across the sleeper contact area.

 

A rail bolt is a high-tensile threaded fastener—including T-bolts, fish bolts, and clip bolts—used to secure rail joint bars, clamp baseplates, or lock adjustable clamping systems such as KPO assemblies. Manufactured from heat-treated carbon or alloy steel (typically Class 8.8 or 10.9), rail bolts are paired with heavy-duty hex nuts and spring washers to maintain high torque retention, clamping force, and structural joint integrity under continuous vibrational stress and dynamic axle loading.

 

A rail shoulder (or rail anchor) is a structural support component cast directly into concrete sleepers during tie manufacturing or welded onto steel baseplates to retain elastic spring clips. Cast from durable ductile iron (such as QT450-10 or QT500-7), the rail shoulder houses and secures the spring clip, providing a rigid lateral stop that absorbs extreme horizontal thrusts generated by passing train wheelsets and prevents track gauge widening.

 

 

A rail insulator (or guide plate) is a specialized electrical isolation block installed between the steel rail foot and the adjacent shoulder or spring clip. Engineered from glass-fiber reinforced polyamide 66 (PA66-GF30), the rail insulator provides high electrical volume resistivity (≥1×108 Ω⋅cm) to prevent signaling current leakage into the ground, while simultaneously offering high mechanical compressive strength to guide the rail laterally and protect clips from direct wear.

 

 

GNEE RAIL operates integrated manufacturing capabilities covering forging, stamping, heat treatment and CNC machining for railway fastening components. Critical dimensions, mechanical properties and material consistency are controlled throughout production according to approved drawings and applicable technical requirements.

 

Quality control includes dimensional inspection, hardness and tensile testing, metallographic examination, and performance verification of fastening systems based on applicable EN 13146 requirements. Production materials and inspection results can be documented through EN 10204 3.1 Mill Test Certificates (MTC) and batch traceability records. For coated components, corrosion resistance can be verified by salt spray testing in accordance with ISO 9227.

 

Technical Documentation Available: MTC · Inspection Reports · Test Reports · Product Drawings

 

 

 

GNEE RAIL uses export-standard packaging designed to protect railway fastening components during handling, loading and international shipment. Packaging methods are selected according to product type, weight and loading requirements, with moisture and impact protection applied where necessary.

 

Clips, bolts, rail pads, insulators and other fastening components can be packed in woven bags, cartons, wooden cases or pallets according to product specifications and customer requirements. Packaging and loading arrangements can also be adjusted to meet container loading requirements, destination regulations and project-specific specifications.

 

Export documentation, packing lists and product quality documents can be provided with each shipment.

 

Request Export Packing Details

 

 

Q1: What is the primary purpose of a rail fastening system?

 

A rail fastening system secures the rail to sleepers, baseplates, or slab track while maintaining track gauge, rail position, and required rail restraint. It also helps control vibration, lateral and longitudinal rail movement, and electrical insulation where required by the track system.

 

Q2: What are the main types of rail fasteners and fastening systems?

 

Rail fastening products include individual components such as elastic rail clips, screw spikes, bolts, rail pads, insulators, anchors, and baseplates, as well as complete fastening assemblies such as E-Clip, SKL, Fastclip, KPO, Nabla, and N-type systems. Selection depends on the rail profile, sleeper or support structure, loading conditions, track design, and applicable standard.

 

Q3: How do rail anchors prevent longitudinal rail movement?

 

Rail anchors, also known as anti-creepers, are installed against the rail foot and sleeper to increase resistance to longitudinal rail movement. They are used where additional restraint against rail creeping is required by the track design.

 

Q4: Why are rail joints designed with an expansion gap?

 

For jointed track, the rail joint arrangement may incorporate a specified expansion gap to accommodate thermal movement. The required gap depends on rail temperature, rail length, joint design, and the applicable track specification. Continuously welded rail systems follow different requirements for managing thermal stress.

 

Q5: What quality documents and tests are required for railway fastening orders?

 

Testing and documentation requirements vary by fastening system, application, and project specification. Common requirements may include dimensional inspection, material certificates, mechanical property testing, fastening performance tests, electrical resistance testing for insulated systems, and repeated-load testing according to applicable EN 13146 methods or other specified standards. EN 10204 3.1 Mill Test Certificates can be provided where required, with additional inspection reports or third-party inspection arranged according to the contract.

 

Q6: What information is required to receive an accurate RFQ for a rail fastening system?

 

Please provide the rail profile, sleeper or support type, fastening system or component type, applicable standard, required quantity, and surface treatment requirements. Project drawings or existing fastening samples are also helpful for confirming compatibility and specifications.

 

Q7: Can GNEE RAIL produce customized fastening components according to customer drawings?

 

Yes. GNEE RAIL can manufacture customized railway fastening components according to CAD drawings, technical specifications or physical samples. Material grade, heat treatment, dimensions, tolerances and surface treatment can be reviewed before production.

As one of the leading rail fastening system manufacturers and suppliers in China, we warmly welcome you to buy high-grade rail fastening system for sale here from our factory. All customized products are with high quality and competitive price.

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