PURPOSE: To obtain an electric welded tube having extremely high resistance to selective corrosion in the electric weld zone, by providing a composition in which C, Si, Mn, P, S, V, and Ti content is respectively specified and the balance consists of Fe and inevitable impurities.
CONSTITUTION: A steel plate is composed of a steel containing 0.01W0.15 % C, ≤0.5% Si, 0.25W2.0% Mn, ≤0.035% P, ≤0.030% S, 0.005W0.30% V, and 0.005W0.06% Ti. Local heating is applied only to the weld zone of the electric welded tube prepared by welding said steel plates, at 900W1,050°C for 1secW5 min. In this way, the electric welded tube having high resistance to selective corrosion in the electric weld zone and suitable used for piping installation for highly corrosive service, e.g., in a wet environment, etc., can be obtained.
| WO/2020/082322 | CONSTRUCTION METHOD FOR IN-WALL PIPE IN TOWER BOILER |
| JPH11500067 | Determination and control of electrical resistance |
| JPS56154290 | LASER WORKING DEVICE |
MIYASAKA AKIHIRO
INOUE SHIRO
| JPS59197519A | 1984-11-09 | |||
| JPS59159933A | 1984-09-10 | |||
| JPS59153840A | 1984-09-01 | |||
| JPS59153839A | 1984-09-01 | |||
| JPS5935629A | 1984-02-27 | |||
| JPS61270338A | 1986-11-29 |
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