Boiling heat transfer tube
US6176302A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 22, 1999 |
| Grant date | Jan 23, 2001 |
| Priority date | — |
| Expiry date | Feb 22, 2019 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF25B2339/0242
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
In boiling heat transfer tube, fins 2 are provided on an outer surface of the tube body 1 in a manner such that the fins 2 each extend in a peripheral direction of the tube and a direction inclined to the tube axis at a pitch P2 in the tube axial direction. Protrusions 4 and recesses 5 are alternately formed in a length direction of a fin, a protrusion coming after a recess or vice versa, by being pressed. Opening 6 widths at the top ends of the cavity 3 between an adjacent pair of fins 2 are narrowed by inward jutting-out of the fins at both recesses 5 and protrusions 4. A profile of each of the protrusions in section perpendicular to the tube axis assumes a trapezoid. An opening width (W) between protrusions in section including the tube axis is 0.13 mm<W .ltoreq.0.40 mm, an angle (.theta.) formed between opposed side surfaces of each recess in section perpendicular to the tube axis is 55 degrees or less. A pitch (P1) of the recesses or the protrusions in section perpendicular to the tube axis is 0.28 mm.ltoreq.P1.ltoreq.0.55 mm. A pitch (P2) of the cavities in section including the tube axis is 0.50 mm.ltoreq.P2.ltoreq.0.90 mm. Ribs are provided on an inner surface of the tube b…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.