| 摘要 |
The U-tube is made from a flat metal sheet, pressed and folded about a transverse line (L) to form two sections (18) which have their inner faces joined together by brazing so that their two pressed recesses (16) form a U-shaped channel which has two parallel branches joined by a curve. The flat metal sheet is of aluminium, coated with a brazing alloy on its inner face, and has a cut-away portion (26) in between the two open ends of the tube. The lower end (32) of the U-tube unit is bent over at right angles to act as a spacer when assembled with other units. |
