AEC $270$

Scraper Opera$$ons

Scraper Produc$$on Calcula$$on

Given a $631$ K scraper fleet opera$$ng to move clay soil. The Payload is $76,000$ lb when loaded. The haul

path is as shown. Assume $50$ minute hours. A scraper has a Ownership and Opera$$ons cost of $$65$ per

hour and a D$10$ has a cost of $$45$ per hour, a D$9$ has a cost of $$37\mathrm{.}50$ per hour and a D$11$ is $$65$ per hour.

All cost are exclusive of fuel. A turn takes $0\mathrm{.}5$ minutes

Travelling Right to Le$$

Leg A $500$ feet TP $=4$ in GR $=0\%$

Leg B $1200$ feet TP$=1$ in GR $=5\%$

Leg C $1800$ feet TP $=1$ inch GR $=0\%$

Leg D $600$ feet TP$=2$ in GR $=-4\%$

$1.$ What Push Cat is recommended $?$

$2.$ What is the RR$,$ GR and TR for each leg in equivalent Grade $\%?$ In lb$/$tgvw$?$

$3.$ What is the speed of the vehicle in each leg in and out?

$4.$ Does the vehicle use the retarder at any $$me$?$

$5.$ What is the number of scrapers required? $($MAX$?$MIN$)$

$6.$ What is the number of Cats Required? $($MAX$?$MIN$)$

$7.$ What is the hourly produc$$on in loose cubic yards?

A

B

C

D

use scrapper data