| Résumé : |
In the processing of wool sheep two major problems can occur during the initial stages of process, both being a direct result of excessive mechanical action.
One is cracking of the pelt where the skins have been preserved either by shade drying or by dry salting and the second is felting of the wool.
These problems were originally avoided by soaking in pits, but dressers now tend to use paddles in the early stages of process. In practice, the paddles are used for convenience of handling with a static soak lasting approximately 12 hours to allow the skins to partially wet back. When softened, the paddles can be turned intermittently without the skins cracking, allowing the mechanical action and detergents to increase the rate of soak.
When fully rehydrated, the wool sheep need to be scoured, the process continuing in the same paddle to reduce the grease content of the wool and to a lesser extent the pelt. Fully hydrated, the skins should be able to withstand continuous running for the 1-2 hour process, but the time is closely dependent upon die length of the wool.
Although drums can be slowed down, the level of mechanical action remains high with the increased risk of felting. Another advantage offered by paddles over alternative equipment is the greater ease when handling sheepskins, in partic-ular in the case of dried sheepskins. |
Aller sur edunet
Accueil
The role of mechanical operations in woolskin production in WORLD LEATHER, Vol. 7, N° 1 (02/1994)
