10/08/2012 Council 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 by multiplying 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 lbs /min. = 600 lbs /mi. Step -by -step calibration procedures 1. Move the spinner out of the way and set the spinner control to zero. In most situations it is not necessary to disconnect the hydraulic hose. 2. Set the auger control for a normal operating mode. 3. Clean the shaft end of the auger and place an index mark on it, so you can count the number of auger revolutions. 4. Instal an auger shield to gain the most accurate measure- ment. 5. Place enough sand and salt in the truck to put a load on the spreader. The material used for calibration should be of the same percentage mix as what you normally use on the roa-d. 6. Rev the engine to normal operating speed of at least 1500 RPM. 7. Let the auger discharge for a few revolutions until there is a steady flow of sand and salt. 8. While the material is flowing steadily, the observer tells the collector to hold the pail under the discharge of the spreader. 9. The observer counts aloud the revolutions of the auger. When the pail is two - thirds full, the observer gives a ver- bal signal and the collector removes the pail. 10. The observer records the number of auger revolutions on the Calibration Worksheet Field Collection Chart. • 11. Weigh the pail containing the sand and salt sample. Remember to deduct the weight of the pail. Record the pounds for this first sample on the Field Collection Chart. 12. Perform steps 9 through 12 two more times, collecting a total of three samples. Record this data on the Field Col- lection Chart. Calculate the average by adding the three numbers together and then dividing that total by three. Record your calculated average pound per revolution on the Field Collection Chart in the bold box and in column C on the Calibration Worksheet Application Rate Chart. 13. This completes the steps to collect and weigh the three samples. 14. Next, count the number of auger revolutions at each set- ting of the sander. One person counts the auger revolu- tions for 15 seconds at every setting while another person times this procedure. Record the results on the Calibra- tion Worksheet, Application Rate Chart Column A. Mul- tiply by 4 to get revolutions per minute (RPM) and record in Column B. 15. Calculate the Discharge Rate by multiplying Column B by the Average Pounds per revolution from Column C (trans- ferred from the Field Collection Chart). 16. Determine the Application Rate (pounds discharged per mile) by multiplying the Discharge Rate (Column D) by the minutes to travel 1 mile at varying speeds as shown in the columns labeled E. Repeat for each control setting. 17. Transfer the numbers from Column E of the Applica- tion Rate Chart to the Calibration Cab Card in the truck. Round off all numbers to the nearest 25 pounds.