Abstract: This method entails: collecting in advance untreated ballast water to which a chlorine-based active substance has not been added; measuring in advance the turbidity of the untreated ballast water; and adding a chlorine-based active substance with an adding amount determined on the basis of the turbidity. The amount of the chlorine-based active substance to be added is set according to the turbidity such that the concentration of total residual oxidants (TRO) is 0.5-3 mg/L (asCl2) when the ballast water is discharged.

Abstract: An automatic wire threading method for a wire-cut electric discharge machine is provided, which is capable of permitting a wire electrode to pass through a fine-diameter machining start hole using of a simple arrangement. After an upper wire supporting portion on the wire supply side of a wire transportation system is moved, along with a cut wire, toward a workpiece disposed in alignment with the upper wire supporting portion, so that the leading end of the wire is in a machining start hole, the upper wire supporting portion is moved away from the workpiece, while keeping the wire end in the hole, and the wire is then transported to the wire delivery side of the wire transportation system, thus completing wire threading.

Abstract: A wire cut electrodischarge machine tool, wherein when the electrode wire breaks during electrodischarge machining, the wire disconnected end is cut and repaired at a repair position far from the electrodischarge machining region by a cutter means, following movement of the wire end is prevented when the cutter is retracted, the electrode wire is automatically laid between upper and lower heads having built-in wire guides, and thus electrodischarge machining on the workpiece is automatically prepared for.

Abstract: An automatic wire connecting apparatus of a wire cut electric discharge machine performs automatic connection of a wire electrode smoothly and reliably. A wire processing unit (90) integrally rotatably coupled to a rotating shaft (61) of a pneumatic motor (60) has a nozzle forming portion (12) which defines a slit (S) that allows a wire electrode (W) to pass therethrough when it is opened, and which defines a nozzle hole (125) capable of fitting with an upper wire guide (12) when it is closed, and is selectively positioned at a wire insertion position or an escape position by a rotary stopper (150). When the wire electrode is broken, the wire processing unit is rotated from the escape position to the wire insertion position by a motor, and thereafter, the nozzle hole forming portion is closed, thereby holding the wire electrode guided through the slit during a rotating operation in the nozzle hole.

Abstract: In a wire cut electric discharge machine, an apparatus is provided, which is capable of detecting completion of wire setting with a simple construction when a wire electrode (W) is automatically extended. Electric power is supplied to the wire electrode (W) from an electric power supplying section (43) through a contact (32) during automatic wire setting. When the wire electrode (W) is fed and brought into contact with an iron plate (44) disposed at a side at which the wire electrode (W) is taken out, an electric potential at the iron plate (44) of the electric power supplied section increases, to thereby detect completion of wire setting.

Abstract: The electric discharge machining apparatus of the wire-cutting type comprises a wire-treating unit (48) movable in the horizonal direction relative to an upper wire guide member (12) between the upper wire guide member and a work table (10) to traverse a wire electrode (W) extending downward from a wire passage (13) of the upper wire guide member. The wire-treating unit has a base block (55) and a movable block (56) that can approach to and separate from the base block to define a slit (60) and a nozzle hole (61) that can be opened and closed between the two blocks. The slit extends in the horizontal moving direction of the wire-treating unit to receive the wire electrode therein. The nozzle hole can be connected to the lower end of the wire passage of the upper wire guide member, and the nozzle hole is constructed so that a spray liquid supplied into the wire passage of the upper wire guide member can be injected into a wire passage (15) of a lower wire guide member (14).

Abstract: A wire feed mechanism of a wire electric discharge machine, which rewinds a wire electrode (P), that is broken during electric discharge machining, by a wire electrode feed reel (1) to a state convenient for connection of the electrode. The mechanism has a clutch (3) having an output shaft (5) coupled to the wire electrode feed reel and creating a coupling torque between input and output members (3a, 3b) in a manner changing in accordance with a feed voltage, and a geared motor (M) coupled to an input shaft (6) of the clutch. When the wire electrode is broken, the feed reel is coupled to the geared motor, that is stopped, through the clutch which receives a high voltage and the input and output members of which are firmly engaged with each other, to be prevented from idling. The thus stopped feed reel is then driven by the geared motor at a predetermined torque and a low speed through the clutch which is supplied with a decreased voltage and loosely engaged, to rewind the wire electrode.