USING CONDITION MONITORING TO PREDICT FURNACE DECAY DURING THE OPTICAL-FIBER DRAWING PROCESS

The drawing furnace plays an important role in the drawing process of optical fibres. The condition of the drawing furnace influences the me lting of silica in the heating zone which, in turn, affects many prope rties of the optical fibre such as attenuation fibre diameter and stre ngth, By investigating the changes of some parameters during the furna ce lifetime, it was found that the drawing tension in the bare fibre i ncreases during the furnace lifetime and the drawing speed fluctuates when furnace decay is serious. Monitoring the combined changes of thes e parameters is a promising method to predict the decay of the furnace .