Abstract: The present invention relates to a cutting method for cutting an upper edge and a lower edge of a cutting plane into a curved shape, when a cutting object is cut by supplying plasma gas to the periphery of an electrode of a plasma torch and ejecting plasma arc from a nozzle. In order to melt the upper edge and the lower edge of the cutting plane to form a curved shape, at least one condition selected from plural conditions including a cutting electric current, cutting speed, height of a plasma torch, angle of the plasma torch, and flow rate of plasma gas upon performing the vertical cutting for forming the upper edge and the lower edge of the cutting object substantially at right angles is changed.

Abstract: [PROBLEMS] To reduce the generation of fume in cutting a material to be cut typified by a steel plate with plasma.

Abstract: [PROBLEMS] To reduce the generation of fume in cutting a material to be cut typified by a steel plate with plasma.

Abstract: The present invention relates to a cutting method for cutting an upper edge and a lower edge of a cutting plane into a curved shape, when a cutting object is cut by supplying plasma gas to the periphery of an electrode of a plasma torch and ejecting plasma arc from a nozzle. In order to melt the upper edge and the lower edge of the cutting plane to form a curved shape, at least one condition selected from plural conditions including a cutting electric current, cutting speed, height of a plasma torch, angle of the plasma torch, and flow rate of plasma gas upon performing the vertical cutting for forming the upper edge and the lower edge of the cutting object substantially at right angles is changed.

Abstract: A plasma torch life duration detecting device according to the present invention aims at detecting a life duration of a plasma torch, detecting a life duration of a plasma torch in accordance with a requested processing precision, and detecting contact between a nozzle protection cover and a workpiece at a lower cost. The plasma torch is constructed in such a manner that a nozzle member 3 having an electrical conductivity is disposed outside of an electrode 2 to maintain electrical insulation against the electrode 2, and a nozzle protection cover 4 having an electrical conductivity is disposed outside of the nozzle member 3 to maintain electrical insulation against the nozzle member 3. The plasma torch life duration detecting device is provided with a voltmeter 7 disposed between the nozzle member 3 and the nozzle protection cover 4, for detecting a voltage between the nozzle member 3 and the nozzle protection cover 4.

Abstract: The present invention relates to a nozzle for a plasma torch, in which the nozzle is detachably attached to the plasma torch and has an injection port for injecting a plasma arc formed at the center thereof, the nozzle for a plasma torch comprising: a water supplying pipe for cooling water; a water draining pipe for the cooling water; an annular water passage arranged around the injection port; and a plurality of connecting water passages for independently connecting the water supplying pipe to the annular water passage and the water draining pipe to the annular water passage.

Abstract: It is an object of this invention to provide a laser piercing method capable of reducing the time required for piercing a workpiece and satisfactorily forming a pierced hole. This invention provides a laser piercing method, in which a piercing process is performed by setting the level of a nozzle 6 during piercing execution to a value higher than the level of the nozzle 6 during cutting execution, setting the pressure of the assist gas during piercing execution to a value higher than the pressure of the assist gas during cutting execution, and setting the level of a focal point O of the laser beam 1 during piercing execution lower than the level of a focal point O of the laser beam 1 during cutting execution and subsequent to the piercing process a cutting process for cutting a workpiece 5 is performed by setting the level of the nozzle 6, the pressure of the assist gas, and the level of the focal point O of the laser beam 1 to a value prescribed for cutting execution, respectively.

Abstract: This invention provides a flow amount adjustment apparatus able to adjust flow amount with high reliability at a low cost without being oversized.

Abstract: It is an object of this invention to provide a laser piercing method capable of reducing the time required for piercing a workpiece and satisfactorily forming a pierced hole.

Abstract: The choices of lenses could be broadened when using lenses of different focus distance and a reduction of size could be accomplished and thus an operation could be made easier by providing a laser-cutting torch in which the laser-cutting torch receives a laser light emitted from a laser oscillator and irradiates the laser light through a nozzle for cutting a targeted cut material.