Rollforming (sometimes also termed open section forming) employs a series of sets of dies in order to bend a sheet of metal little by little until the desired profile (cross section) is obtained. Rollforming is a continuous operation of bending in which a long metal strip or sheet- usually of coiled steel - is passed through sets of rolls (or stands), each of which performs only a small incremental portion of the bend until the finished cross section profile is achieved. Roll forming is especially useful in the production of parts of long length, and in large quantities. Metal rollforming is quite like traditional pipe and tube making. However, rollforming is able to create more complicated profiles. In both pipe and tube making and in roll forming metal sheets are bent with roller dies, in which each roll pair works the sheet progressively until the final shape is obtained. Rollforming differs from the older techniques in that it can be combined with prepunching, postpunching, and midpiercing inline, together with sweeping prior to cutoff.

Another advantage of rollforming is that the same rollforming machinery can be used to produce a wide variety of cross section profiles. Each different profile requires a specially designed set of rolls. The fundamental roll design resembles a flower - i.e. a sequence of profile cross sections (one for each set of rolls). Because rollforming is an exact operation and involves high machinery costs, computer simulation is used in order to validate the design of the roll stands to make sure that the metal product won't be stressed unduly, and also to minimize the total number of rolls required. Examples of rollformed applications include automobile chassis sections, window guides, and impact bars. These can be prepunched, then rollformed, midpierced inline, rollformed some more, and then welded and cut off in one continuous operation.

As in pipe and tube mills, rollforming can be used with practically all metals, nonferrous as well as ferrous. Coils of stainless steel, high strength and low alloy steel, martensitic steel, as well as aluminum can be rollformed. It is possible to emboss coils of aluminum or steel with finishes that simulate wood grain (e.g. for garage doors). When using embossed metals the roller dies must be adjusted so as not to roll out the embossment. Prepainted and vinyl laminated sheets can also be rollformed but not welded. Rollforming is a process of great versatility which permits innovative design. Setting a rollforming system up requires a skilled rollform engineer's expertise, as well as considerable collaboration between the manufacturer and the vendor in order to develop a successful product.

No matter what your particular metal rollforming application demands, Samco's experienced and highly trained staff of experienced professionals are the world leaders in state-of-the-art rollform design and installation. Choice of the correct equipment for the job, skillful design of the tooling and product, thorough training of the rollforming machinery operators, and vigilant maintenance of the rollforming system are our specialty.

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