| 摘要 |
PURPOSE:To provide the insulating pipe material which prevents electrolytic corrosion and crevice corrosion arising in the case of connection of different metallic pipes in an oil well, etc., and is excellent in the improvement of both the adhesion and corrosion resistance of films. CONSTITUTION:The low corrosion-resistant pipe material 1 and the highly corrosion-resistant pipe material 2 are screwed and connected directly or by means of a coupling 3. Amorphous insulating ceramics layers, at least the extreme surface layer parts of which are crystalline, are clad in a range L of >=60mm from the pipe end at the inside and outside surfaces of the pipe material of the low corrosion-resistant pipe material 1, in a range L of >=60mm from the pipe end at the inside and outside surfaces of the pipe material of the highly corrosion-resistant pipe material 2, in a range L of >=60mm from both pipe ends of the inside and outside surfaces of the coupling 3 and further in spacing parts A, B when these pipe materials are connected. |
