铜管外壁整体式三维翅片复合加工成形机理

通过对滚压-犁切-挤压复合方法加工三维整体翅成形的试验研究, 重点分析了整体式三维翅片的成形特征、条件和成翅机理. 当滚压深度ar和犁切-挤压深度ap为0.2 mm, 转速nr为50 rpm, 进给速度 f 为0.16 mm/r, 在外径Φ=16 mm, 壁厚t=1.5 mm的紫铜管外表面得到翅高为0.25 mm的三维翅片. 进一步研究分析表明, ar和nr、f和ap之间存在着相互匹配的关系, 随着加工参数变化得到了两种不同的结构: 一种为V型槽与U型槽混合结构; 另一种为单一V型槽结构. 对滚压加工与犁切-挤压加工相互影响规律进行了分析, 当滚压加工和犁切-挤压加工都成单一V型槽结构时实现了整体式三维外翅片滚压-犁切-挤压一次成形.

Formation Mechanism of 3D Integral-fin by Composite Processing Method Based on Outside Surface of Copper Tubes

Based on the experimental research on the fin formation mechanism by rolling-ploughing-extrusion composite processing method, the formation characteristics, machining conditions and formation mechanism of 3D integral-fin of copper tubes were studied. The experimental results showed that when both rolling depth ar and ploughing-extrusion (P-E) depth ap were 0.2 mm, rotational speed nr was 50 rpm, amount of feed f was 0.16 mm/r, 3D fins structure with height of 0.25 mm on outside surface of red copper tube with diameter Φ=16 mm and wall thickness t=1.5 mm was obtained. Further analysis indicated that there was a matched relationship between ar and nr, also f and ap. Two different fin structures were got with parameters changing in grooves forming with rolling-ploughing-extrusion composite forming method. One was the compound structure with V-shaped groove and U-shaped groove, the other was the single structure with V-shaped grooves. Based on the analysis of interaction of rolling and P-E processing, it was found from the result that the outside 3D integral-fin could be achieved by rolling-ploughing-extrusion compound processing when single V-shaped groove structures were formed by both rolling and P-E processing.