Improving Log Trucking Efficiency by Using In-Woods Scales

Abstract

Abstract We evaluated weight data from 47,953 truckloads of wood delivered to forest products mills in nine southern states to determine the effect of in-woods scale use on reducing the variability of net and gross weights. Four mill-owning companies provided the data and indicated whether in-woods scales were used for each load. We used these data to compare the mean tare, net, and gross weights of truckloads using scales to those not using scales. Trucks using scales had average tare weights only 108 lb greater, but their net payload averaged 1,799 lb higher than trucks not using scales. The coefficient of variation for the net payload was 38% lower for loads with scales than those without (P < 0.001). Individual southern states have different regulations regarding maximum gross vehicle weight (GVW), so we calculated a GVW index to remove state bias and allow comparisons of loads across states. Loads using scales were within 2% of the legal maximum GVW 54% of the time compared with 30% for loads not weighed in-woods. We estimated haul costs for trucks using scales at $7.44 per ton, compared with $7.74 per ton for trucks not using scales (P < 0.001). We found that 11% of loads with in-woods scales had haul costs exceeding $8.00 per ton, compared with 32% of loads not using scales. Across all data, scales represent a 4% savings on per-ton haul costs with even greater savings available as fuel prices increase.