Methods and apparatus for producing fibers from igneous rock, including basalt include heating igneous rock by electrical conductive coils to achieve an homogenous melt and forming homogenous fibers from the melt.

Methods of reshaping ferrules (20) used in optical fiber cables assemblies (170) are disclosed. The reshaping methods reduce a core-to-ferrule concentricity error (E), which improves coupling efficiency and optical transmission. The methods include measuring a distance (δ) and angular direction (θ) from a true center (30) of the ferrule to the core (46), wherein the true center (30) is based on an outer surface (26) of the ferrule. The methods also include reshaping at least a portion (26P) of the ferrule (20) to define a new true center (30′) of the ferrule (20) and reduce the distance (δ). A variety of reshaping techniques are also disclosed.

Methods of reshaping ferrules (20) used in optical fiber cables assemblies (170) are disclosed. The reshaping methods reduce a core-to-ferrule concentricity error (E), which improves coupling efficiency and optical transmission. The methods include measuring a distance (δ) and angular direction (θ) from a true center (30) of the ferrule to the core (46), wherein the true center (30) is based on an outer surface (26) of the ferrule. The methods also include reshaping at least a portion (26P) of the ferrule (20) to define a new true center (30′) of the ferrule (20) and reduce the distance (δ). A variety of reshaping techniques are also disclosed.

A manufacturing method of a porous glass base material for optical fiber includes: controlling a flow rate of a raw material liquid of an organic siloxane by a liquid mass flow controller; introducing raw material liquid to a raw material liquid nozzle of a vaporizer by a raw material liquid pipe; ejecting raw material liquid into the vaporizer; mixing raw material liquid and carrier gas to vaporize raw material liquid to form mixed gas; supplying mixed gas to a burner; combusting mixed gas together with a combustible gas and a combustion supporting gas in the burner to produce SiO.sub.2 particles; depositing SiO.sub.2 particles on a starting core base material to form the porous glass base material; and closing an open/close valve on a flow path of the raw material liquid pipe to stop supply of raw material liquid, while continuing to supply carrier gas, combustible gas, and combustion supporting gas.

A manufacturing method of a porous glass base material for optical fiber includes: controlling a flow rate of a raw material liquid of an organic siloxane by a liquid mass flow controller; introducing raw material liquid to a raw material liquid nozzle of a vaporizer by a raw material liquid pipe; ejecting raw material liquid into the vaporizer; mixing raw material liquid and carrier gas to vaporize raw material liquid to form mixed gas; supplying mixed gas to a burner; combusting mixed gas together with a combustible gas and a combustion supporting gas in the burner to produce SiO.sub.2 particles; depositing SiO.sub.2 particles on a starting core base material to form the porous glass base material; and closing an open/close valve on a flow path of the raw material liquid pipe to stop supply of raw material liquid, while continuing to supply carrier gas, combustible gas, and combustion supporting gas.

An eccentric state determining method which is performed by a controller and for determining a state of eccentricity of a coating of a glass fiber with respect to the glass fiber. The coating is formed around the glass fiber. The method includes acquiring measurement values for an outer diameter of the optical fiber at positions along a longitudinal direction of the optical fiber, calculating a standard deviation of the measurement values, and determining the state of the eccentricity based on the standard deviation.

An eccentric state determining method which is performed by a controller and for determining a state of eccentricity of a coating of a glass fiber with respect to the glass fiber. The coating is formed around the glass fiber. The method includes acquiring measurement values for an outer diameter of the optical fiber at positions along a longitudinal direction of the optical fiber, calculating a standard deviation of the measurement values, and determining the state of the eccentricity based on the standard deviation.

This invention addresses technical problem of optimizing output of a melt cascade, which is used in production of mineral fiber (so called mineral wool as known in state of the art being stone wool, slag wool or other type of mineral wool). These technical problems are solved by steps of determining (a) trajectory of movement of a melt stream, (b) melt concentration relative to surrounding air between the first and the second rotating wheels, and (c) movement vector, and further by regulating of movement of melt stream (i.e., drop mass), said regulation mostly achieved through variation in point of contact of melt and rotating wheel or plurality thereof. This is achieved by determining three key parameters: (a) trajectory of movement of melt stream, (b) melt concentration relative to surrounding air between the first and the second rotating wheels, and (c) movement vector, and further by analyzing these three key.

This invention addresses technical problem of optimizing output of a melt cascade, which is used in production of mineral fiber (so called mineral wool as known in state of the art being stone wool, slag wool or other type of mineral wool). These technical problems are solved by steps of determining (a) trajectory of movement of a melt stream, (b) melt concentration relative to surrounding air between the first and the second rotating wheels, and (c) movement vector, and further by regulating of movement of melt stream (i.e., drop mass), said regulation mostly achieved through variation in point of contact of melt and rotating wheel or plurality thereof. This is achieved by determining three key parameters: (a) trajectory of movement of melt stream, (b) melt concentration relative to surrounding air between the first and the second rotating wheels, and (c) movement vector, and further by analyzing these three key.

A manufacturing apparatus of a porous glass base material for optical fiber includes: a liquid mass flow controller for controlling a flow rate of a raw material liquid of an organic siloxane; a vaporizer for mixing the raw material liquid and a carrier gas to vaporize the raw material liquid to form a mixed gas in which a raw material gas and the carrier gas are mixed; a raw material liquid nozzle for ejecting the raw material liquid into the vaporizer; a carrier gas supply pipe for supplying the carrier gas into the vaporizer; a raw material liquid pipe for introducing the raw material liquid into the raw material liquid nozzle; a burner for combusting the mixed gas together with a combustible gas and a combustion supporting gas to produce SiO.sub.2 fine particles; a mixed gas pipe; an open/close valve; and a purge gas supply pipe.