What Material Grades and Lengths Are Available for the 136RE Rail?

The 136RE Rail: Grade and Length Options

The 136RE rail, also designated TR68 in some global regions, is a premium heavy-duty track section used on mainline railways, heavy-haul freight corridors and mining transit systems. It has a standard height of 7 5/16 inches (185.74 mm), a base width of 152.4 mm and a nominal mass of 67.5 kg/m (136 lb/yd). The section is manufactured to AREMA (American Railway Engineering and Maintenance-of-Way Association) specifications, and the available material grades and lengths are designed for heavy-haul freight and high-speed Class I railroads.

Material Grades (Steel Chemistry)

Rail steel for the 136RE profile is primarily categorised by hardness and microstructure, with wear resistance and fatigue strength as the deciding factors.

Standard Strength (SS)

The baseline carbon-steel grade for general mainline use, with a Brinell hardness of around 300-320 HBW. It suits mixed traffic and lines where head wear is moderate.

High Strength / Head Hardened (HH)

The most common choice for 136RE in heavy-load areas. The rail head is heat treated to reach 370-400 HBW, which significantly extends service life in curves and high-wear zones.

Low-Alloy and Premium Grades

Specialised chemistries that add elements such as chromium or molybdenum are specified for extreme conditions, including heavy-tonnage coal and ore lines, to prevent shelling and internal defects.

Chemical Composition of AREMA Rail Steel

AREMA 2019 grade	C %	Si %	Mn %	P %	S %	Ni %	Cr %	V %
Carbon steel	0.74-0.86	0.10-0.60	0.75-1.25	less than or equal to 0.020	less than or equal to 0.020	less than or equal to 0.25	less than or equal to 0.30	less than or equal to 0.010
Low alloy, Standard Strength (SS)	0.72-0.82	0.10-0.50	0.80-1.10	less than or equal to 0.020	less than or equal to 0.020	less than or equal to 0.15	0.25-0.40	less than or equal to 0.010
Low alloy, Intermediate Strength (IS)	0.72-0.82	0.10-1.00	0.70-1.25	less than or equal to 0.020	less than or equal to 0.020	less than or equal to 0.15	0.40-0.70	less than or equal to 0.010
Low alloy, Head Hardened (HH)	0.72-0.82	0.10-1.00	0.70-1.25	less than or equal to 0.020	less than or equal to 0.020	less than or equal to 0.15	0.40-0.70	less than or equal to 0.010

Mechanical Properties of AREMA Rail Steel

AREMA 2019	Strength grade	Yield strength N/mm2	Tensile strength N/mm2	Elongation %	Brinell hardness HBW
Carbon steel	SS	511 min	983 min	10 min	310 min
Carbon steel	IS	724 min	1069 min	10 min	350 min
Carbon steel	HH	828 min	1179 min	10 min	370 min
Low alloy steel	SS	511 min	983 min	10 min	310 min
Low alloy steel	IS	552 min	1014 min	8 min	325 min
Low alloy steel	HH	828 min	1179 min	10 min	370 min

Standard Lengths and Welding Practice

In North America, rail is produced in standard stick lengths of 39 ft or 80 ft. The 80 ft length is increasingly preferred because it halves the number of bolted or welded joints compared with 39 ft sections. Custom lengths can be supplied for turnouts, bridges and short-radius curves. Most modern mainlines use continuous welded rail (CWR): sticks are flash-butt welded at the plant into ribbons of about 1,440 ft, delivered by specialised rail trains and then welded into the track on site.

FAQ

What material grades are available for the 136RE rail?

The 136RE rail is available in Standard Strength (SS) and Head Hardened (HH) grades, plus low-alloy chemistries on request. The HH grade is particularly suited to curved track and environments with severe friction from heavy axle loads.

What are the standard delivery lengths for the AREMA 136RE rail?

Standard lengths are typically 39 ft, 40 ft and 80 ft, aligned with conventional heavy-haul track requirements. Precise custom cutting is available for continuous welded rail (CWR) installations.

Can you provide compatible fastening systems for the 136 lb rail?

Yes. Track stability requires matched accessories, including standard joint bars (fishplates), heavy-duty tie plates, rail clips and track spikes fitted for the 136RE profile.

What is the difference between 136RE and 115RE rails?

The main differences are weight and load capacity. The 136RE has a heavier weight per yard, a wider head and a thicker web than the 115RE, making it the superior choice for extremely heavy freight, while the 115RE suits moderate traffic.

How is dimensional accuracy of the 136RE rail section ensured?

Shaping and rolling lines are controlled with ultrasonic testing and laser measurement tools, so that height, base width and web thickness stay within the standard tolerance requirements.

Is rail drilling offered for jointed track installations?

Yes. Custom rail end drilling is available based on engineering drawings, so that bolt holes align with the joint bars during on-site track assembly and installation time is reduced.