What are the standard bolt hole dimensions for S20 railway track

What are the standard bolt hole dimensions for S20 railway track?

 

S20 railway track, which is a light steel rail manufactured according to the DIN 5901 standard, typically requires bolt holes tailored for M16 or 5/8" to 3/4" fishbolts depending on the specific joint requirements. While bolt hole sizes can be customized, standard DIN 5901 S20 rails are often pre-drilled for these fasteners to join 19.8 kg/m rail sections in industrial and light railway applications.

 

Standard Bolt Hole Dimensions for S20 Rail (DIN 5901)

 

 

 

• Bolt Size: Frequently uses M20 or similar (such as 3/4" or 5/8" BSW) high-strength fishbolts.

 

• Bolt Hole Diameter: Typically designed for a standard fit, often falling in the range of 22 mm to 24 mm (assuming a 20mm-22mm bolt diameter for clearance), though the exact hole size depends on the fishplate design.

 

• Hole Type: Commonly oval or round, punched or drilled depending on manufacturer options.

 

• Web Thickness: 10 mm.

 

Key S20 Profile Specifications

 

DIN S20 rail is a European standard (DIN 5901) light rail, with a standard mass of 19.8 kg/m. Its key dimensions include a height of 100 mm, base width of 82 mm, head width of 44 mm, and a web thickness of 10 mm. It is commonly used in industrial, mining, and crane tracks.

 

Key Dimensions of DIN S20 Rail (DIN 5901 Standard)

 

 

• Height: 100 mm
• Base Width: 82 mm
• Head Width: 44 mm
• Web Thickness: 10 mm
• Mass/Weight: 19.8 kg/m
• Standard Length: Usually 6 m – 10 m or 12 m

 

 

Size	Rail height(mm) A	Bottom Width(mm) B	Head Width(mm) C	Web Thickness(mm) t	Weight(kg/m) *
S10	70	58	32	6	10
S14	80	70	38	9	14
S18	93	82	43	10	18.3
S20	100	82	44	10	19.8
S24	115	90	53	10	24.4
S30	108	108	60.3	12.3	30.03

 

When is a rail joint used for Light Rail S20?

 

A rail joint for Light Rail S20 (typically 19.8 kg/m, DIN 5901 standard) is used to connect individual rail segments to form a continuous, stable track, particularly in industrial, mining, or modular transit applications. These joints are typically needed when rails are not continuously welded, requiring a mechanical connection to maintain track alignment, gauge, and structural continuity.

 

Rail joints for S20 rails are used in the following scenarios:

 

• Initial Track Installation: To join standard S20 rail segments (commonly 6, 8, or 10 meters in length) using fishplates and bolts to form a longer track.

 

• Temporary or Modular Lines: In mining tunnels, factory floors, or warehouse logistics, where tracks may need to be assembled, disassembled, or relocated frequently.

 

• Replacement of Damaged Sections: When a section of S20 rail is damaged, a jointed connection is used to bridge the new section with the existing track.

 

• Curved Tracks: Staggered joints are used on curves to manage centrifugal forces and maintain stability.

 

• Electrical Isolation: Insulated joints are used where electrical signals must be separated between track sections.

 

• Connecting Different Rail Types: Compromise joints are used to connect S20 rails to other rail profiles, such as those with different weights or heights.

 

FAQ

 

Q: What happens if the hole is drilled too high or too low on the 7 mm web?

A: If the hole is off-center, the S20 rail joint bar will not seat correctly in the fishing space. This creates an uneven load on the 30.00 mm head, leading to rapid wear and potential fracture of the web. The hole must be drilled precisely at the neutral axis to preserve the RAIL S20 MATERIAL STRENGTH.

 

Q: Can I use M20 bolts in a 24mm hole?

A: While they will fit, there will be excessive play in the joint. This play causes the rail ends to "clap" or "hammer" under load, which quickly destroys the 100.00 mm profile geometry and leads to the loosening of the fastening clips on the 82.00 mm base.

 

Q: Do you recommend drilling holes at both ends of a 5.8m rail?

A: Yes, for most S20 light rail systems, having pre-drilled holes at both ends is the most efficient way to ensure rapid onsite assembly. This allows the S20 rail joint bar to be installed immediately, maintaining a consistent track gauge and alignment across the entire length of the installation.

 

Q: Does the 55Q material grade make drilling more difficult?

A: Because 55Q grade is harder (200–240 HB), it requires specialized high-speed steel or carbide drill bits. Attempting to drill these rails onsite with standard equipment often leads to overheating and bit failure, which is why factory CNC drilling is the preferred choice for maintaining the S20 rail specifications.

 

Q: Are there standard hole patterns for 12-meter S20 rails?

 

A: Yes, the end-hole patterns remain the same (typically 55-110 mm), regardless of the rail length. Whether you are using 5.8-meter lengths for export or 12-meter lengths for domestic projects, the dimensions for the S20 rail joint bar connection must remain consistent to ensure global compatibility.

 

Get a Quote in 24 Hours

 

GNEE RAIL provides DIN 5901 S20 rails, full-size crane rails (QU, A series), and international standards like ASCE and JIS directly from our manufacturing facility. We supply all matched S20 rail joint bars, high-tensile bolts, and rail clips to ensure your track system is fully compatible. Our CNC workshop handles precision cutting and custom drilling to your exact S20 rail drawing specifications. Send your technical requirements to GNEE RAIL now to receive a detailed quote and CAD support for your upcoming project.