Roll-forming and roll-bending machines | Safeguarding for Specific Types of Machinery

Roll-forming and roll-bending machines primarily perform metal bending, rolling, or shaping functions. Roll forming is the process of bending a continuous strip of metal to gradually form a predetermined shape using a self-contained machine. Roll-forming machines may also perform other processes on the metal, including piercing holes, or notches; stamping; flanging; and stretchbending. Roll bending is essentially the same process, except that the machine produces a bend across the width of flat or pre-formed metal to achieve a curved or angular configuration. Roll-forming and roll-bending machines frequently are set up and operated by one person.

Roll-forming and roll-bending machine hazards

The most common type of amputation hazard associated with roll-forming and roll-bending machines are point of operation hazards created by in-running nip points. Amputations occur when the hands of the operator feeding material through get caught and are then pulled into the point of operation. Causes of amputations related to roll-forming and roll-bending machines can occur from the following:

§  Having an unguarded or inadequately guarded point of operation;

§  Locating the operator control station too close to the process;

§  Activating the machine inadvertently; and

§  Performing cleaning, clearing, changing, or inspecting tasks while the machine is operating or is not properly locked or tagged out.

An employee wearing gloves caught his left hand in a roll-forming machine, resulting in partial amputation of two fingers. The employee was standing close to the moving rollers, feeding flat steel sheet from behind and catching it on the front side. There was no point of operation guard on the front roller and the foot operating pedal was very close to the machine.

Engineering controls

Roll-forming and roll-bending machines are available in a wide variety of sizes and designs, and safeguarding methods must be tailored for each machine. Several factors affect the ways to safeguard the equipment, including machine size, operating speed, thickness of product, length of production runs, required production accuracy, sheet feeding methods, and part removal methods. Depending on the size and type of machine, a number of different safeguarding devices and methods may be required to adequately protect the operator as well as other workers nearby. For example, you can do the following:

§  Install fixed or adjustable point of operation guards at the in-feed and out-feed sections of machines. If the stock or end-product does not differ greatly from run to run, a fixed guard may be preferable. If the stock or end-product is variable, however, an adjustable guard may be more suitable.

§  Install fixed point of operation guards to cover the sides of the rollers to prevent an employee from reaching into the in-going nip points of the rollers.

§  Install fixed or interlocked guards to cover any other rotating parts, such as a power- transmission apparatus.

§  Install safety trip controls, such as a pressure-sensitive body bar or safety tripwire cable on the in-feed section of the machine to shut down the machine if an employee gets too close to the point of operation.

§  Install emergency stop controls that are readily accessible to the operator.

§  Use an awareness barrier guard with an interlocking gate around the perimeter of the machine to prevent unauthorized entry.

§  Locate foot pedal controls away from the point of operation and guard them in such a way as to prevent inadvertent activation.

§  Allow only one control station to operate at any one time when a single machine has more than one set of operator controls, this does not apply to the emergency stop controls which must be operable from all locations at all times.

§  Position operating stations in a way that ensures operators are not exposed to the machine’s point of operation.

§  Safeguard operator control stations to prevent inadvertent activation by unauthorized employees.

Work practice and administrative controls

You can also prevent hazards from this equipment by doing the following:

§  Develop and implement safe operating procedures for roll-forming and roll-bending machines and conduct periodic inspections of the operation to ensure compliance.

§  Ensure that all operators receive appropriate on-the-job training under direct supervision of experienced operators until they can work safely on their own.

§  Ensure that operators use the jog mode during feeding operations if appropriate and that they maintain a safe distance from the machine’s rollers.

§  Require workers to perform servicing and maintenance activities under an energy control program in accordance with §1910.147.