Upon arrival at Hamilton Rios, the raw material goes through the first classification process which consists of separating the fibers by taking into consideration the impurity rate and the length of the fiber. In this stage, the end result is the separation of the good quality raw material - sisal type 1 and sisal type 2 - and the sisal which contains stains, short-length fibers and high impurity rate - refugo.
Only fine quality sisal goes through the brushing process. For this, machines named 'batedeiras' are used. These machines have a similar concept of the decorticating machines, and are composed of a drum of approximately 0,60 cm of diameter and six plain blades of 5 cm of width, protected by a metallic cover which rotates in the opposite direction of the ones in the decorticating machines.
An operator holds the thickest part of the bundle of fibers and introduces it in the machine in order to start the cleaning through the means of the hitting of the blades in the fibers in an extension of 70% of the length. Subsequently, the operator inverts the position and holds the bundle the other way around to complete the cleaning on the other tip of the fibers. There is usually a loss of 8% of the original weight of the fibers due to the removal of residues of dust and short-length fibers (bucha) during this process.
In order to improve this process, Hamilton Rios adopted the DB system – double brushing system – that consists of going through the above-mentioned process twice, which guarantees cleaner and drier sisal, with fewer impurities.
Hamilton Rios is the only company which has developed, through investments in research and development, an exclusive machine for the drying of the sisal which presents humidity rate above the standard rate required.
The sisal containing humidity above 13,5% goes through this machine for the drying process.
This process consists of placing the fiber for 15 minutes inside a stove with temperature varying between 80 to 100° C. After this period, the sisal is transported to the cooling sector, where high-power fans cool down the sisal before it goes through the revision process.
Only Hamilton Rios has the technology of drying the sisal, which is particularly important, especially for the sisal which will be exported inside containers and through a transit-time which exceeds 30 days until it reaches its final destination port. Because of this process, the sisal which carries the mark RISANA arrives at its destination completely dry, free from black stains and wet parts.
After the brushing and drying of the sisal, the fibers get transported to rectangular tables where workers, usually women, make a second classification of the fibers, which consists of separating the fibers according to the standard classification in the producing country. Only after the classification, that takes into consideration the length of the fiber and its impurity rate, that the sisal is revised and sorted according to its class and type.
After revision, the fiber goes through the pressing process, operation that prepares the sisal for its transportation from the local industry to foreign countries. This process uses hydraulically pressing machines made of boxes for the placing of the sisal, a cylinder for the pressing of the fiber and an electric motor that activates the pressing process. The dimensions of the boxes where the fibers are laid are 1,50 cm x 0,50 cm x 0,60 cm, producing bales of weight between 100 and 300 kg. The tying is generally done by the use of sisal ropes that go around the sisal 6 to 8 times.
On the packing up process, a label is placed on the bale so that it carries the specifications of the sisal:
After the pressing process, the bales go to appropriate and safe storehouses.
The storage is a relatively simple operation, as long as the security measures are observed.
The storehouses at Hamilton Rios offer total security, as they provide the crucial technical conditions for the maintenance of the quality of the products and for inspection as per legislation.
Only bales presenting humidity rate of up to 13,5% are stored. By doing so, the lots stocked are composed of bales of the same class and type, easily identifiable.