Economy of Farm Machinery at Higher Speed (I)

High-speed Economy in Terms of Initial Price

Abstract

The main aim of this study is to find an optimum higher speed of farm machinery to achieve greater field capacity and performance. The most economical speed was sought for by computing the initial prices of implements (Japanese plow and tractor-mounted rotary tiller) and tractor at higher speeds or at larger operating widths.
The operating resistance acting uponimplements and tractor was assumed to be described as a quadratic function of operating speed. Then the engine power and weight of implements and tractor at a certain operating speed were approximately calculated. Thus the initial prices of implements and tractors were obtained and compared with each other.
The main results were the followings.
(1) Speeding-up is more economical than widening of operating implements up to a certain level of higher speed.
(2) The optimum speeds in terms of initial price are 7km/hr (about 2 times of the conventional speed) for Japanese plow and 6km/hr (about 3 times as large) for tractor-mounted rotary tiller.
(3) Economical profit of speeding-up is greater for smaller implements and tractor than for larger ones so for as the initial prices are concerned.