There are three different methods of shearing metal in manufacturing. Metal shearing can be done at all three stages of making the products length, width. Other methods of cold shearing are used by pipe and stamping facilities. Steel mills use many different shearing methods that include Hydraulic, torch and flying shear methods when running a hot product.
Cold drawn steel use the shear press to cut sheet steel into various sizes for fabrication. These shears can also bend and shape the product into angles, saving on time and cost of welding angles for fabrication. Pipe making facilities use a shear that is called a splitter. It will trim the edges at a fast rate to give the edges a more unified texture for the pipe seams. These shears have the ability to shear any grade of high or low carbon steel to a desired width that the customer wants for the diameter of the pipe.
Plasma shears are for stainless steel. Plasma torch shears are used strictly for this purpose. A regular torch system for cutting high or low carbon steel will only melt stainless at a much slower rate. Making it to slow to cut stainless during a casting operation where the steel has to be cut on the move. Plasma torches offer a much cleaner and faster cut to stainless steel. The plasma shearing method saves on valuable time and cost to make the product for the customer.
During a Casting sequence in a mill operation, all things to the type steel being run are took into consideration before the cast starts. Steel grades for high and low carbon steel only require hydraulic shears to cut the steel into lengths. The shear will traverse with the steel as it is being produced through straightening rolls that guide it into the shear for cutting. This method of shearing ensures that the steel has time to shear and not cause a jam during the process. Sensors in the rolls motors let the computers know when to cut the length. A 8×8 bloom cut 15 feet will produce over a mile of reduced angle steel. So length is important to any steel shearing process.
Sheet steel facilities use different shearing methods based on the types of steel they run. Hydraulic shears are by far the most powerful cutting systems in steel manufacturing, but with new and harder steels coming onto the market these days. Shearing methods have to sometimes be changed in order to compensate for hardness and grade of steel. It is a fascinating process to watch. The power it takes to shear hot or cold steel relies totally on the thickness of the product. Titanium steel blades of the shear will cut through a hot bar or bloom like butter, but when cutting cold steel like sheet or rounds it will take a much different type of shear and pressure to cut the steel.
Steel mill rolling mills cut the lengths of fabricated product on the fly by using a shear called”The flying shear.” This shear has long arms that are in line with the fast moving steel. Steel moving at 45 miles and hour requires this method of shearing finished product to desired lengths. If the flying shear misses one cut it will cause the angle, flat or round steel to cobble. A simple miss can cause a big mess by sending the steel looping up through the rafters. The product looks like spaghetti as it snakes its way up and around the machinery below. Steel mill work can be tedious when things of this nature happen. Instead of a product rolling out onto a cooling bed for stacking. A worker will now have to cut the cobbled steel with hand torches and use a overhead crane to clear the product out of the pass line. Still the flying shear method is the best for this type of operation. Shears will still be the most important feature in and steel making facility.