JPS6371986U - - Google Patents

Description

[Brief explanation of the drawing]

Fig. 1 is a schematic perspective view showing an embodiment of a high-frequency electric resistance welding pipe welding device equipped with the composite impeder of the present invention, Fig. 2 is a longitudinal cross-sectional view thereof, and Fig. 3 is a longitudinal cross-sectional view of the composite impeder of the present invention. , FIGS. 4A to 4D, and FIG. 5 correspond to the cross sections taken along the lines in FIG. Fig. 6 is a perspective view showing the induced current by the preheating coil, Fig. 7 is a longitudinal cross-sectional view of the pipe after welding, and Figs. 8 and 9 are main parts showing examples of conventional high-frequency electric resistance welding pipe welding equipment, respectively. FIG. 10 is a diagram showing the temperature change at both edges of the tube material when welding is performed using the device, FIG. 11 and FIG. 12 are longitudinal sectional views of the tube material, and FIG. This figure is a perspective view showing another conventional example of a high-frequency electric resistance welding pipe welding device, and FIG. 14 is a perspective view illustrating the flow of induced current when the pipe material has a small diameter. 1...Pipe material, 3...Induction coil, 5...Gap,
5a, 5b...edge, 8...preheating coil, 20...composite impeder, 24...silicon steel plate laminated core, 26...ferrite core.

Claims (1)

[Scope of utility model registration request] A tube material is formed into a tube shape having a V-shaped gap, and power with a frequency of 20.000 Hz or less is supplied to a preheating coil placed in front of the V-shaped gap of the tube material to heat the vicinity of the opposing edges of the tube material. This impeder is used in a high-frequency electric resistance welding device that preheats and continuously electrically welds the opposing edges of a V-shaped gap. A silicon steel plate laminated core and a ferrite core are installed at fixed positions on the outer periphery of the rod between the installed proximal holder and distal holder, and the core is covered with an insulating tube. Both ends are sealed with a proximal holder and a distal holder, and a water inlet and a water inlet for introducing cooling water into the insulating cylinder to cool the silicon steel plate laminated core and the ferrite core are passed through the insulating cylinder. A composite impeder characterized by being equipped with a drain port for draining cooled water.