Electric Resistance Welded (ERW) Tube Making Process

Webco purchases prime sheet coils from the approved steel suppliers that conform to Webco's raw material specification requirements.

Continually forms the slit coil to tubular shape through series of forming and fin rolls. Mill tooling is designed by our engineering group to perform consistent dimensional control and result in optimum welding condition.

Both edges are welded continuously using high frequency or low frequency electric resistance induction welding method.

Due to the upset work during welding process, a small amount of metal will be extruded from the upset edge. This squeezed metal, called weld flash (or weld bead) will be removed by specially designed cutting tool from the inside and outside of the tube.

Conduct in process non-destructive inspection on weld area using ultrasonic testing method to detect any possible weld discontinuities to ensure the quality of the weld.

Through sizing roll section of the tube mill, tube outside diameter will be reduced slightly and size to final outside diameter dimension. Outside dimension can be maintained to a half industrial standard for special application.

The tube is straightened longitudinally in vertical and horizontal planes through a series of offset rolls achieving a straight tube with a minimal degree of cold work. Straightness can be maintained to a half industrial standard for special application.

100% inspection of the tube by the industrial test specification or special customer testing specification with eddy current or an ultrasonic non-destructive electric test method.