1. Plane clearance
One side of the surface presents the phenomenon of upward convex and downward concave, with a ruler placed on the surface, during which there is a certain gap called the plane gap; The main reason is uneven metal flow on both sides of the profile wall or improper straightening roller.
Elimination method:
Adjust the length of mold working belt to ensure the
aluminum extrusion profile flow evenly; When the upper and lower rollers are properly matched, the plane gap can be corrected.
2. The size is out of whack
The size of each part of aluminum extrusion profile exceeds the tolerance requirement of the size of the profile section drawing. The usual size error are: wall thickness error, round rod, round tube outside diameter error, flat square tube long (wide) edge error, no specification profile angle error, opening size error; Most of the reasons are caused by unreasonable size reservation during mold design, or deformation during mold extrusion, or mold use time is too long, or improper control of tensile rate during tensile straightening and other factors.
Elimination method:
(1) Establish mold files, and timely scrap molds that are deformed, used for a long time and have out-of-tolerance wall thickness; Improve mold design and mold manufacturing process;
(2) If the angle is out of line and the opening size is out of line, the mold working belt should be corrected to ensure the aluminum extrusion profile flow evenly;
(3) When stretching and straightening, the amount of stretching should be properly controlled; To the aluminum extrusion profile with an opening, when the chuck is put on the appropriate pad at the opening, can prevent the stretching of the mouth.