Mitsubishi Denki Kabushiki Kaisha

Nippon Steel Corporation

Kawasaki Steel Corporation

Toshihiko Baba

Akiyoshi Uomori

Takao Kawanami

Yoshimasa Komatsu

Hisashi Takahashi

Masayuki M Nakamura

Akimichi Takeda

Junji Miyata

Keiji Sodeno

Takio Okuda

Naotake Ritoh

Satoshi Hanai

Susumu Mizugami

Mamoru Tabuchi

Tadayasu Tsuchitani

Kouichi Ishii

Takao Suzuki

Katsunori Hara

A welding apparatus for welding a trailing end of a preceding strip and a leading end of a subsequent strip including a shear device for cutting them in parallel and a back bar device for supporting the ends of the strips. Provision is made to detachably connect the shear device and the back bar device and move them along a common rail between the strip ends.

Welding apparatus

A method and apparatus for flash welding are disclosed wherein a first predetermined voltage is applied between a pair of workpieces to be welded to generate flashes therebetween, and a second predetermined voltage lower than the first predetermined voltage is then applied between the workpieces to maintain fine flashes when the temperature of weld surfaces of the workpieces has reached a predetermined temperature. The workpieces are upset when the total number of flashes has reached a predetermined value. The pressure welding is maintained with an upsetting pressure sufficient to upset the workpieces and slightly higher than a pressure at which the workpieces are deformed near their recrystallization temperature until the temperature of weld surfaces has decreased to lower than the recrystallization temperature. The applied voltage and the upsetting pressure are controlled in accordance with the weld progress.

Method and apparatus for flash welding

A welding apparatus comprises a pair of clamping devices for clamping the workpieces to prevent slip under applying significantly large force to the butting surfaces for the butt welding operation and a pair of electrode tables for feeding a welding current. The welding apparatus need not comprise a step gauge bar nor an auxiliary clamp in order to set the projecting degree.

Welding apparatus with forward shiftable electrode tables

In a flash welding apparatus, different length guides and driving devices thereof are formed on lower parts of an inlet side electrode table and an outlet side electrode table and the electrode tables and a compact rotary shear unit are arranged in the direction perpendicular to a strip line when both of the electrode tables are approached and one of the guides is commonly used as a guide for shifting a flash trimmer lower unit and a guide is formed on one of the upper electrode frames of the electrode tables so as to shift a flash trimmer upper unit and the rotary shear unit of the inlet side electrode table and the rotary shear unit of the outlet side electrode table and a pair of the upper and lower trimmer units are aligned in the plan view.

Flash welding apparatus

A rectangular waveform voltage is applied between electrodes for welding by using a variable voltage-variable frequency type inverter as the power source for welding whereby the local short-circuit between workpieces can be immediately changed to the flash whereby the fine flash can be continuously generated to remarkably improve the quality of the welded part, and the voltage control can be attained without changing the voltage waveform.

Flash butt welding apparatus

A flash and upset material formed in a flash welding operation can be removed by a machining of the flash and upset material for a short time after the welding operation by providing a workpiece clamping function by a main clamp and providing a welding current feeding function by an electrode table. The main clamp is heavy whereas the electrode table is light so as to be easily movable, whereby the electrode table in the light weight can be backwardly shifted for a short time after the welding operation and a space for inserting a tool holder equipping with a tool for machining a flash and upset material, is formed near the welded line. Since the flash and upset material can be machined during the time maintaining the softness of the flash and upset material at relatively high temperature for a short time, the machining can be attained by only pair of tools.

Apparatus for machining flash and upset material formed in flash welding

A welding apparatus comprises a pair of suspension type electrode press devices for clamping an upper electrode and a lower electrode in perpendicular relation to workpieces for synchronizing them, whereby a clamping force is treated as the inner force of the pushing mechanism and the apparatus can be miniaturized. The surfaces of the workpieces can be uniformly clamped by the upper and lower electrodes whereby the consumptions of the upper and lower electrodes are substantially the same and the calibration of the positions of the upper and lower electrodes for consumption is not required. The welding apparatus is especially effective for continuous rolling in single or plural lines of a rolling apparatus for rolling hot steel billets, etc. and welding them.

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Amagasaki, Japan

Toshihiko Baba