2012-07-25 CC Packet - Laserfiche WebLink

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Snow and Ice Control Calibration Procedures for Spreaders Four basic steps 1. Measure the amount of sand and salt discharged in one auger revolution. 2. Count the number of auger revolutions per minute at each setting. 3. Determine the discharge rate bymultiplying the number of revolutions per minute by the amount of sand and salt discharged per revolution. 4. Multiply the discharge rate by the minutes it takes to travel one mile. Example: Speed Time to travel one mile 20 mph = 3 minutes Minutes /mile x Discharge rate /minute = lbs /mile at setting number 4 3 min. /mi. x 200 Ibs/min. = 600 lbs/mi. Step -by -step calibration procedures 1. Move the spinner out of the way and set the spinner 12. Perform steps 9 through 12 two more times, collecting a control to zero. In most situations it is not necessary to total of three samples. Record this data on the Field Col - disconnect the hydraulic hose. lection Chart. Calculate the average by adding the three 2. Set the auger control for a normal operating mode. numbers together and then dividing that total by three. 3. Clean the shaft end of the auger and place an index mark Record your calculated average pound per revolution on on it, so you can count the number of auger revolutions. the Field Collection Chart in the bold box and in column 4. Install an auger shield to gain the most accurate measure- C on the Calibration Worksheet Application Rate Chart. ment. 13. This completes the steps to collect and weigh the three 5. Place enough sand and salt in the truck to put a load on samples. the spreader. The material used for calibration should be 14. Next, count the number of auger revolutions at each set - of the same percentage mix as what you normally use on Ling of the sander. One person counts the auger revolu- the road. tions for 15 seconds at every setting while another person 6. Rev the engine to normal operating speed of at least 1500 times this procedure. Record the results on the Calibra- RPM. lion Worksheet, Application Rate Chart Column A. Mul- 7. Let the auger discharge for a few revolutions until there is tiply by 4 to get revolutions per minute (RPM) and record a steady flow of sand and salt. in Column B. 8. While the material is flowing steadily, the observer tells 15. Calculate the Discharge Rate by multiplying Column B by the collector to hold the pail under the discharge of the the Average Pounds per revolution from Column C (trans - spreader. ferred from the Field Collection Chart). 9. The observer counts aloud the revolutions of the auger. 16. Determine the Application Rate (pounds discharged per When the pail is two -thirds full, the observer gives a ver- mile) by multiplying the Discharge Rate (Column D) by bal signal and the collector removes the pail. the minutes to travel 1 mile at varying speeds as shown in 10. The observer records the number of auger revolutions on the columns labeled E. Repeat for each control setting. the Calibration Worksheet Field Collection Chart. 17. Transfer the numbers from Column E of the Applica- 11. Weigh the pail containing the sand and salt sample. lion Rate Chart to the Calibration Cab Card in the truck. Remember to deduct the weight of the pail. Record the Round off all numbers to the nearest 25 pounds. pounds for this first sample on the Field Collection Chart. 84