EFW(Electronic Fusion Welded) pipe is formed by rolling plates and welding the seam. Cheaper than Seamless and easy to produce by customer specification. It has the advantage that it is possible to make the width thinner than Seamless. Commonly used for general pipe, boiler/ heat exchanger, sanitary, general lifesaving etc.
Semi-Seamless Tube is a general welded pipe without beads. Tube without beads from PLUG drawing are strong to high temperature and pressure which apply to machine or facility which requires solidity and preciseness.
Not only cheaper than Seamless but also thinner in thickness. Recently various business groups such as semiconductor, heat exchanger, petrochemical, shipbuilding, cylinder, shaft, automobile plant are using it.