What is the name of the sleeve used for melting fiber

Protection sleeve. Fused fiber refers to the optical fiber into the fusion machine to form the action or production process, fiber optic protection tube, fused fiber optic cable protection casing optical cortical bare fiber protection tube, mainly used for ultra-high voltage, ultra-high voltage, high-voltage substations, transmission lines, power plants and industrial chemical, marine, medical industry equipment strong electromagnetic field environment of the fiber optic fiber splicing.