What is the cut to length line?
Coil cut to length line, also known as coil dividing line, blanking line, or CTL, is designed to unfold and flatten the steel coil, then cut it to the required width or length, and rewind it to obtain the final profile.
The slit multi-head steel coil manufactured according to the cut to length line refers to the winding steel coil cut to a specific length through the main coil, also known as the slit fixed-width coil. Generally speaking, the cut to length line is composed of three main parts, namely, coiler, Slitter and coiler. At the beginning of the production cycle, the rolled steel coil is fed and flattened through the coiler system, so as to eliminate the defects on the surface of the steel coil.
In the next stage, the flattened material will be loaded into the pinch points between the circular cutting wheels installed at the top and bottom of the slitting system. The slit-to-width coil will then be rewound by the take-up equipment.
Introduction to the technological process of coil cut to length line
Uncoiling of cut to length line:
The uncoiling process in the coiler system starts by automatically feeding the steel coil or main coil into the double cone or expanding mandrel single-end coiler. The double cone coiler is more suitable for heavy-duty applications, and the multi-functional mandrel coiler is an excellent solution for light and heavy loads.
The rolled steel coil is transported to the cone through the pusher ramp and the rapid loading steel coil trolley. The raw materials are loaded into the cone of the uncoiler through the ramp of the pusher and the rapid coil loading car. The loader screws the mandrel into the inner diameter of the main coil material and then screws it away from the cone or mandrel.
Before using the straightening tool, the material will be stripped to allow the coil head to enter the edge guide smoothly. The flattening operation of the coil is particularly important when flatness and the absence of defects on the surface of the material are critical in the further treatment of the coil.
The cutting line of cut-to-length line:
At this stage, the unwound material will be loaded into the slitting system, which consists of two parallel spindles and rotary cutting tools. The cutting tool will partially enter the steel coil, resulting in cracks or fractures on both sides of the steel. The sheets of the cut to length line are then separated from each other. Many applications require rubber peel rings to provide a better edge and eliminate any burrs and defects that may interfere with downstream operations.
After precision cutting, the outer edge of the product has edge trimming, which needs to be processed by the waste winding machine. In some cases where the product being cut is very thin, the machinist can use the annular pit. This may take up a slit width coil of different thickness, especially when the edge is significantly thinner than the central part. The annular pit mentioned here can also manage additional volumes prior to the tensioning phase.
Normally, tension brackets are used on the slitting line before rewinding the system. The tensioner is responsible for creating the main coil, the diameter of the center part of which is larger than the edge. If there is no such tensioning support in the length cutting line, the material will be removed from the central part of the pile more quickly and the two sides will be hung loosely.
Rewinding of cut to length line:
Before stacking sheet products, it is necessary to rewind the coiler system with the slit to the width by expanding the mandrel and cut the coiler system to the length line. Recoiler systems can usually be expanded with expansion pads or blades over a diameter of 60 cm or more. The coiler system is matched with the upper arm shaft with a separating disc, which is directly installed on the circular slitter. This preserves any interleaving conditions for narrow coil applications. Next, the processed plates will be unloaded from the mandrel onto the coiler and stacked into bundles by the plate stacker.
Leading manufacturer of metal cut to length line
Foshan Te Xiang Machinery Co., Ltd is a China leading manufacturer of metallic processing machines, including slitting line, cut to length line, stainless steel polishing line, ERW tube mill line, roll forming machines, embossing line and etc.
TX Machinery’s metal cut to length line is designed and built with the highest accuracy, efficiency and performance to process a range of black and non-ferrous metal materials for metal service centers and steel mills, the automotive industry, the home appliance industry and many other industries around the world. Please feel free to contact us if you have any questions about our metal cut to length lines.
Contact TX Machinery