Underground Mine Tunnelling – Northwest US

Application Type
Underground Mine Tunnelling – Northwest US

Machine Type
Multi Purpose Vehicle (MPV) for tunnelling (articulated tractor trailer combination)

Tire Size & Type
355/65R15 (9.75×15) Radial Tire

Site Conditions
Rough hard rock terrain with significant grade inclines/declines. Typical cycle time of 60 minutes. Typical distance of 1-6 miles (2-10 km) as tunnel extends. Typical 16 hours of operation per day.

Tire Problem
MPV heavily overloaded with prefabricated concrete wall pieces. Site conditions prone to flats daily. Due to severe loads, polyurethane fill was known to break down/fail in similar applications on this machine type. Solid tires would cause heavy shock transmission damage and fail within hours. Average tire service life of 1-2 months.

Unique to the application the tunnel’s circular designed walls and machine tire axle camber did not allow the tire to have a full contact patch/footprint on the ground which it would otherwise have on a flat surface.

Trojan Solution
Installed Trojan HD Soft Core into radial tire.

Success / Outcome
With Trojan Soft Core the tire service life hours have improved significantly up to 24 months (12 times improvement). Trojan Soft Core eliminated flat tire downtime and assisted the tires to carry the heavy loads safely.