28 October 2019

The shaped cleats

From the very beginning of agricultural mechanization, the tyre has been and will be one important part for the performance from the machine to the field. In this evolution, we have gone from the iron wheels to the most modern VF tyres (low pressure that optimize the traction of the machine). In this evolution, the cleats are one decisive part that seeks the greatest possible efficiency. However, what are the needs that the tire cleats have to overcome? This is the first question engineers ask when they are designing a tire. If you are looking for traction and only traction, a cross block in the direction of travel is the most efficient. Quite the opposite situation we could have if we look for comfort in the wheel, in this way the length and closeness among cleats will give us a greater contribution of stability and comfort.

For this reason, the cleat has to pass efficiently the different conditions that we demand it. The main characteristics for a tractor tyre are: traction, comfort, self-cleaning, durability, noise and rolling stability. These characteristics are, in many cases, antagonistic to each other. As we mentioned at the beginning, traction is obtained with one type of cleat and comfort with another type. Therefore, the objective is to achieve a tyre that achieves the improvement of current performance without harming its opponent.

Nowadays, modern tractors are machines designed to carry out a lot of great efforts, but at the same time they reach high speeds, which affects the comfort and stability of a machine that is quite high in size and that works very long days on many occasions. Therefore, in design, many different variables are used to obtain the final product, and these would be the premises to be taken into account:

  • If we are looking for traction: very crossed cleats on the direction of travel and high distance between them to be able to make the necessary traction.
  • If we are looking for comfort: very close and long cleats. Better in longitudinal direction.

As these two factors are a priori opposed, all manufacturers of agricultural tyres opt for intermediate products, which are capable of meeting these two needs at a the same time as far as possible. Each manufacturer choose, some of them for straight cleats at 45 degrees or with two different levels of position (a first line at 40 degrees and a second at 50 degrees). In this case Vredestein, which is one of the solutions we prefer, makes the central area of the cleats very unit to give continuity, comfort and low rolling noise, while the final area is almost 90 degrees above the direction of travel, which acts fully on the traction. This is achieve with a smooth curvature, which makes the stability of the cleats another of its great strengths. The size of the tyre also affects the design of its cleats. A compact tractor, for work in vineyards or fruit trees, requires different performance than a 400 hp tractor for pulling with a plough. For this reason, the cleats are manufactured with the robustness required according to the size of the tyre and the size of the tyre varies according to the performance of the tractor.

The tyre sector is constantly evolving, testing different materials and componentsĺ such as the chemistry used, types of rubbers, resins, polymers, etc. in addtion to being constantly testing to seek continuous improvement and be able to have more and more an optimized tyre.

Versión en español.

10 October 2019

Harvesting grapes: winery tasks

In Spain, one of the most characteristic tasks during the beginning of autumn is the grape harvest. It is true that these tasks have evolved a lot in recent years, about 20 years ago this was a completely manual and very social work, now the grape harvest is done almost completely mechanized. We have already talked about harvesting in some articles in past post from previous years, so this time we have gone to the winery to wait for the grape.

We have visited the winery called the "Cooperativa del Campo Nuestra Señora de la Asunción", which is located in our village (La Alberca de Záncara - Cuenca). It is a small winery that today it is true that does not have much more activity because nowadays, it is not an area of many vineyards (purple garlic is the engine of the economy), but it receives a few million kilograms of grapes during the harvest season. The winery is rented to the "Bodegas Gallego & Laporte" company, which is responsible for marketing the wines made there. By the way, as you can see in the photos, a part of the winery is quite old and beautiful. It is very well preserved, so we recommend that you visit it.

As you can see in our video, we witnessed the reception of a truck of Syrah grapes variety. In the video we explain the process of grape reception that is completely mechanized, highlighting all the tasks performed there from the moment the truck enters through the doors of the winery until it leaves the winery premises
  1. The truck is weighed to know the amount of grapes that will be delivered to the warehouse. At the same time, several samples of the grape are taken to find out the degree of sugar in the grape (Baume degrees). The farmer will charge the grape according to the kilograms and the Baume degree.
  2. Once weighed and with the samples of grade collected, the truck unloads in the well. These wells are made of stainless steel and have screw conveyors that will take the grapes to the next step.
  3. The grapes pass through a destemming machine that separates the grains from the stalk. The stalk is discarded and the grains pass to the following machine where they are pressed.
  4. The grapes are pressed to obtain the must (grape juice). The must, together with the pulp of the grains are transferred to stainless steel tanks where they will stay for several days.
  5. The must and pulp in the stainless steel tanks are in constant recirculation so that a perfect mixture is made between the must and pulp. In this way, the must takes on colour as it is a black grape.
  6. When the density of the must and pulp is adequate, the must goes to some tanks where it will be fermenting during the days that the oenologist considers appropriate and the pulp goes to the pressing machines.
  7. The pulp is pressed to obtain the remaining must, which is sent to the tanks for fermentation.
  8. The waste from the press, called grape pomace, is taken out of the cellar for later use in the generation of vinegars, for example.
The must that is fermenting in the tanks, once the fermentation process is finished, the tasks of decanting (transferring the wine from one tank to another) and filtering will begin... this will give a quality La Mancha wine... but these tasks will be another topic that we will deal with in the future.

Versión en español.