The coil straightener is perhaps the heart of each wire processing line: it compensates for any undesirable deformation of the flat sheet metal strip during coil binding. The perfect coil straightener for each application is determined by the size, the gauge and the center field of the coil straightener rolls. The optimum performance of a coil-wrapped strip is also dependent on the quality of the feed coil. Feed coils are made of materials such as steel, aluminum, brass and nickel.
There are three main factors to consider when selecting a coil straightener. The first one is the tolerance of the wire. Another is the center field of the strip; and the third is the overall performance. In addition, to those, the cost factor is also a very important consideration. The type of coil straightener used is largely determined by the type of electroplating: nickel-silver contact, induction heating, galvanic-ion heating or cold dip galvanizing.
The third important factor to consider when purchasing a coil straightener is its ability to remove coil set to produce precision diameters at acceptable frequencies. The precision of a machine is affected by three factors: the feed rate, the filler size and the roving frequency. As a result, a machine may need to be upgraded if the current feed rate is less than 1800 rpm and the current filler size is less than 0.15 mm.
Some power straighteners, especially those that operate with low amperage currents, have a provision for increasing the thickness of the coils even further. The increased thickness achieves both increased stiffness and improved power transmission, thus providing better accuracy and consistency. Power coated steel plate coil straighteners are used in applications where the accuracy of the workpiece requires greater accuracy than can be achieved with standard cold rolled steel.
A power coated coil straightener uses an electrochemical process which is unaffected by electrochemical reactions occurring in the power coating. This ensures that the straightened area will always be equally resistant to any lateral or rotational movement. Power coated plates can also be installed at a larger diameter than cold-rolled steel, increasing the surface area available. For projects where a tight tolerance to thermal expansion is important, power coated heaters and coiled tubes are suitable.
Another important consideration in choosing the right coil straightener is its compatibility with the core wire size. The larger the core size, the less amount of current should flow through the device. Larger core sizes are typically available only to consumers who purchase devices equipped with feed rate meters, feed rate control, and heavy duty construction. For those working with light gauges or small gauge wire, it is generally not necessary to purchase a power straightener with a larger core size. A good rule of thumb is to purchase a power straightener with a core size that is three times smaller than the largest wire measured across the entire core.