The invention discloses ultrafine
glass wool obtained by
centrifugation. The ultrafine
glass wool comprises 63.0-66.5wt% of SiO2, 1.4-3.0wt% of Al2O3, 5.5-7.5wt% of CaO, 1.5-3.0wt% of MgO, 0.4-1.3wt% of K2O, 14.2-16.0wt% of Na2O and 5.5-7.6wt% of B2O3. The Al2O3 content is in a range of 1.4-3.0% so that liquid glass
crystallization tendency is reduced, fibers are flexile and burr and fractures are avoided; and the B2O3 content is in a range of 5.5-7.6% so that liquid glass
viscosity is reduced at a
fiber formation temperature of 1050+ / -10 DEG C and fibers are thinned easily. The diameters of 90% of the
glass wool fibers are normally distributed in a range of 2-4 microns and the lengths of 92% of the glass
wool fibers are normally distributed in a range of 2-3 centimeters. The invention also discloses a preparation method of the ultrafine glass
wool. The preparation method comprises the following steps of selecting raw materials satisfying requirements, putting the raw materials into a
kiln, carrying out melting to obtain transparent liquid glass, introducing the transparent liquid glass into
centrifugation heads, and carrying out fibration at a flow rate of 76+ / -2kg / h at each
centrifugation head to obtain the ultrafine glass
wool. The ultrafine glass wool has a low heat conduction coefficient, uniform layering and good sound-absorbing and heat-insulation performances. The ultrafine glass wool can be used for preparation of sound-insulation and
noise-reduction cotton felt in an
airplane cabin plate, sound-insulation and heat-insulation cotton felt for the wall and roofing, heat insulation plates, and other sound-absorbing and heat-insulation products.