Rolling method

Mainly roll the steel plate billet into a flat round shape on the rolling machine:
1, the blank in the length of the middle part of a line drawn as a control line
2, respectively, the billet two halves rolled into two halves of the circle, it is not difficult to see, the flat circle of the straight section part is exactly the remaining straight edge part. Rolled flat round, the main thing is to control the misalignment, to accurately center and keep the bus and roll parallel. In the roll flat circle, also prone to over-roll phenomenon, then had to pull it apart after spot welding. The shape after the roll should generally make the butt joints slightly concave down a bit, do not protrude.

Straightening

After the roll circle should be rounded, rounding is in the butt joint welding longitudinal seam double-sided welding and then to the coiler rounding. Rounding is more difficult and time-consuming than rolling circle, the specific method is:

1, the first on the roll on the straight section of the flat circle repeatedly roll roll, the two straight sections alternately

2, with the upper roller on the full circumference of the repeated roll roll, the upper roller pressure down and lift the amount can be adjusted first. Before rounding the butt joint inside and outside the weld to strengthen the height should not be more than 1mm, otherwise rounding will occur when jumping, the damage to the coiler is greater. This method rolled out of the cylinder roundness deviation is very small, ellipticity can be controlled within 3 mm. However, due to the need for two rolls, rounding time-consuming, relatively low productivity. If there is no pre-bending equipment, tools, single piece or batch production of cylindrical workpiece, the method is a good method, and greatly save material. The scope of application of the method: rolled into a flat circle after the semicircular diameter should be greater than or equal to the minimum diameter of the coiler can roll cylinder.