Insulation felt of optical fiber induction drawing furnace

A heat preservation felt of an optical fiber induction drawing furnace comprises a heat preservation cylinder, the heat preservation cylinder is formed by curling an outer heat preservation layer, a middle graphite heat preservation body and an inner heat preservation layer, the outer heat preservation layer, the middle graphite heat preservation body and the inner heat preservation layer are tightly bonded, a plurality of reinforcing devices are arranged outside the heat preservation cylinder, and a plurality of temperature measuring holes are formed in the heat preservation cylinder. According to the utility model, inaccurate temperature measurement caused by softening and collapsing of the thermal insulation cylinder in a long-term high-temperature state and abnormal optical fiber parameters caused by non-uniform furnace temperature field can be prevented, the service life of the thermal insulation cylinder can be prolonged, and the purpose of reducing the optical fiber manufacturing cost is achieved. 一种光纤