NEUMÁTICOS AGRÍCOLAS EL LIDER EN EL CAMPO.

Presentación del tema: "NEUMÁTICOS AGRÍCOLAS EL LIDER EN EL CAMPO."— Transcripción de la presentación:

1 NEUMÁTICOS AGRÍCOLAS EL LIDER EN EL CAMPO

2 Reemplazo de Neumáticos
Agrícolas

3 Circunferencia de rodamiento
Reemplazo de Neumático Circunferencia de rodamiento La Circunferencia de Rodamiento La circunferencia de rodamiento es la distancia desplazada por una revolución del neumático. La Razón de la Circunferencia de Rodamiento = La circunferencia de rodamiento delantera dividida entre la circunferencia de rodamiento trasera If a customer wants to change the tire sizes on a mechanical front-wheel-drive tractor, the front and rear replacement tires must have the same rolling circumference ratio as the original front and rear tires. Rolling circumference is the distance traveled in one revolution of the tire.

4 Circunferencia de rodamiento
Reemplazo de Neumático Circunferencia de rodamiento Neumáticos Originales 18.4R38 Traseras, 14.9R28 Delanteras Neumáticos de Reemplazo Here's an example of how to calculate the rolling circumference ratio. Assume the original tires are 18.4R-38 rears and 14.9R-28 fronts. The customer wants a 20.8R-38 rear replacement tire. You need to determine the FWD front tire size. 20.8R38 Traseras, ? Delanteras

5 Circunferencia de rodamiento
Reemplazo de Neumático Circunferencia de rodamiento Neumáticos Originales Traseras 18.4R38 — circunf. de rodamiento = 206" Delanteras 14.9R28 — circunf. de rodamiento = 161" The rolling circumference for 18.4R-38 rear tires is 206 inches. The rolling circumference for 14.9R-28 front tires is 161 inches. Both of these numbers are found in the Farm Tire Data Book. The ratio of front to rear is 161 inches divided by 206 inches. The rolling circumference ratio is No se redondea la razón de circunferencia de rodamiento. Razón de la circunferencia de rodamiento = 161"  206" = .7815

6 Circunferencia de rodamiento
Reemplazo de Neumático Circunferencia de rodamiento Neumáticos de reemplazo Traseras 20.8R38 — circunf. de rodamiento = 214" Delanteras 214" x = 168" Then, you look up the rolling circumference for the 20.8R-38 rear replacement tires in the Farm Tire Data Book; it's 214 inches. Multiply 214 inches by the rolling circumference ratio you calculated for the original tires You want a front tire with a rolling circumference of 168 inches. Again, look in the Farm Tire Data Book, and you find that 18.4R-26 tires have a rolling circumference of 168 inches. the ratio is the same as the original tires. Circunf. De rodamiento se redondea hacia arriba ( a 168) 18.4R26 – circunf. de rodamiento = 168"

7 Reemplazo de Neumático
Conclusión La circunf. de rodamiento delantera dividida entre la circunf. de rodamiento trasera = Razón de la circunferencia de rodamiento La razón es un número “SAGRADO” Siempre redondear números parciales al inmediato superior Se puede ir hasta una circunferencia de 2” arriba pero nunca por debajo de la razón To summarize: Divide the rolling circumference of the front tires by that of the rear tires to determine the rolling circumference ratio. Remember that the rolling circumference ratio is a "sacred" number. It must be maintained if the customer changes tire sizes. Whenever you're doing calculations that result in partial numbers, always round up. And finally, you can go "up" 2 inches on the rolling circumference of a tire, but never "down".

8 Avance / Arrastre en un Tractor de Doble Tracción Asistida

9 neumáticos delantero y trasero son iguales =
Avance / Arrastre La velocidad del neumático delantero es más rápida que la velocidad del neumático trasero = AVANCE La velocidad del neumático delantero es más lenta que la velocidad del neumático trasero = ARRASTRE La velocidad de los neumáticos delantero y trasero son iguales = CERO AVANCE/ARRASTRE Lead/lag refers to the relationship between the speed of the front wheels and the speed of the rear wheels. If the front wheels' speed is faster than the back wheels' speed, we say the tractor has a lead condition. If the front wheels' speed is slower than the back wheels' speed, the tractor has a lag condition. And if the front and back wheels move at the same speed, the tractor would have zero lead/lag. But since front and back tires are always different sizes, there's always going to be some amount of lead or lag.

10 Es un proceso que requiere de 3 personas. El Conductor del tractor .
Medición del Avance / Arrastre Es un proceso que requiere de 3 personas. El Conductor del tractor . Quien cuente las vueltas de los neumáticos traseros . Quien cuente las vueltas de los neumáticos delanteros. Testing for lead/lag is a four-step process that requires three people: one to drive the tractor, one to count the revolutions of the rear wheel and one to count the revolutions of the front wheel.

11 Test de Avance/Arrastre
Medición del Avance / Arrastre Testing for Lead/Lag Test de Avance/Arrastre Neumaticos Marcados

12 Marcas en las neumáticos delanteros y traseros
Medición del Avance / Arrastre Marcas en las neumáticos delanteros y traseros Testing for lead/lag is a four-step process that requires three people: one to drive the tractor, one to count the revolutions of the rear wheel and one to count the revolutions of the front wheel.

13 Con los neumáticos delanteros acoplados
Medición del Avance / Arrastre Con los neumáticos delanteros acoplados Next, find a long, straight piece of ground with firm soil. Start with the chalk line on the rear tire pointing straight down. With the front wheels engaged, drive the tractor forward. Using the chalk line as a guide, have someone count the number of revolutions of the rear tire and another person count the number of revolutions of the front tire. When the rear tire has made exactly 10 revolutions, stop the tractor and write down the number of revolutions the front tire made, to the nearest tenth of a revolution. To ensure an accurate reading, repeat the procedure at least one more time. 10 Vueltas ? Vueltas

14 Con los neumáticos delanteras desacoplados.
Medición del Avance / Arrastre Con los neumáticos delanteras desacoplados. Now, with the front wheels in neutral (disengaged), repeat the same process. After the rear tire has made 10 revolutions, stop the tractor and write down the number of revolutions the front tire made, to the nearest tenth of a revolution. Again, it's a good idea to repeat the procedure at least one more time to ensure that your reading is accurate. Once you've got accurate readings both with and without the front 10 Vueltas ? Vueltas

15 Avance deseado: 2% Avance aceptable: 0 a 5% Arrastre aceptable: 0%
Porcentaje de Avance / Arrastre Nº de vueltas con neumático delantero en cambio. Nº de vueltas con la neumático delantero en neutro. – 1 X 100 = % de avance/arrastre Si el resultado es mayor que 0 = % Avance Si el resultado es menor que 0 = % Arrastre Avance deseado: 2% Avance aceptable: a 5% Arrastre aceptable: 0% Here's the formula you use. Divide the number of revolutions of the front tire with the front wheels engaged by the number of revolutions of the front tire with the front wheels in neutral, and then subtract one. If the resulting number is greater than zero - a positive number - the tractor has a lead condition. If the resulting number

16 Porcentaje de Avance / Arrastre
Here are two examples. In the first example, suppose the number of revolutions of the front tire engaged was 14.3, and the number of revolutions of the front tire in neutral was Dividing 14.3 by 13.8, you get Subtract one from 1.036, and you get a positive .04. This means the tractor has four percent lead. In the second example, let's say the number of revolutions of the front tire engaged was 13.3, and the number of revolutions of the front tire in neutral was Dividing 13.3 by 13.8, you get .96. Subtract one from .96 and you get a negative .04. This means the tractor has about a four percent lag. Tractor A tiene 4% Avance: Aceptable Tractor B tiene 4% Arrastre: Inaceptable El tractor B necesita un neumático con un 6% mayor de circunferencia de rodamiento.

17 Conclusión Avance / Arrastre
Condiciones inapropiadas de Avance o Arrastre pueden causar una desgaste prematuro en los neumáticos y daños en el sistema de transferencia del tractor. Con el manejo sobre ruta (los neumáticos no están diseñados para circular en ruta), SIEMPRE tener en posición neutral el eje delantero para eliminar avance o arrastre ya que el daño en esta caso se puede acentuar. A final note. The wear and tear on the front tires and the tractor's transfer case as the result of lead/lag is increased during on-road travel. That's why it's important to always have the front wheels in neutral when the tractor is driven on-road.