Motor Grader

Formula : 

A = S x (Le - Lo) x 1000 x E

A = hourly operating area (m²/h)

S = Operating Speed (km/h)

Le = Effective Blade length (m) 

Lo = Width of overlap (m)

E = Job efficiency

Le = Effective Blade Length = Blade Length x Sin (angle)

The width of overlap is generally 0.6 m. This overlaps accounts for the need to keep the tires out of windrow on the return pass 

Example :

A 140H motor grader width a 3.66 m moldboard is performing road maintenance, average speed is 13 km/h with carry angle 60 degrees. Job efficiency is 0.90.

 

Solution :

Effective blade = 3.66 x sin 60 = 3.17 m

Production :

= 13 km/h x (3.17 - 0.6 m) x 1000 x 0.90 

= 30 069 m²/hr