In order to prevent or alleviate the defect of
Aluminum bended pipe/tube and obtain satisfactory quality of
Aluminum bended pipe/tube, corresponding countermeasures should be taken to solve the problem. Firstly, within the allowable range of product design structure, the
bending pipe fittings should be designed with larger bending radius as far as possible. At the same time, the bending machine with side boost and tail push mechanism should be selected when purchasing equipment.
1. It is inevitable that the outer arc thinning is determined by the characteristics of the bending process for small radius pipe bending, but measures should be taken to overcome the excessive thinning. The common and effective method is to use a pipe bender with a booster on the side or a pusher on the tail, or both, so that the auxiliary or pusher mechanism can push. Moving the pipe forward can counteract the partial resistance of
pipe bending, improve the stress distribution on the pipe section and make the neutral layer move out, so as to reduce the tube wall thinning. The speed of boosting and pushing is determined according to the actual situation of the elbow to match the bending speed. At the same time, check whether the advance amount of mandrel installation is appropriate, and make necessary adjustments when inappropriate.
2. For the tube with serious flattening outside the circular arc, the pressing die (wheel) can be designed as a structure with an inverse deformation groove to reduce or eliminate the flattening degree of the tube when it is bent. When the mandrel diameter is too small or the mandrel wear is serious, the mandrel should be replaced. The unilateral clearance between the mandrel and the inner wall of the pipe should not be more than 0.5mm. At the same time, the advance of the mandrel installation should be appropriate. In addition, when installing the mould, ensure the groove axis of each part is on the same level.
