Machine Guards for industrial robots

Innovation in the industrial sector has led to the introduction of robots, which are in turn changing the management of spaces within factories. The ever-increasing adoption of robot cells in several industrial applications entails the installation of mandatory protective measures for robots and robotized areas in order to preserve the safety of workers.

More than ever, operators are sharing their working spaces with automated machinery and industrial robots. This has prompted the need to define universal standards for the safety of machinery/industrial facilities and, thus, that of operators.

The international, Type-C EN ISO 10218-2:2011 technical Standard sets the safety requirements for the integration of industrial robots, industrial robotic systems and robotic cells.

Robotic cells are defined as teams of machines that include one or more robots, i.e. multi-purpose manipulators operating via automatic control and which are programmable on 3 or more axis. The EN ISO 10218-2 standard details the hazards related to these systems and provides a list of requirements needed to prevent or minimize the risks that come with them.

The EN ISO 10218-2 standard was conceived for the specific hazards linked to the integration of industrial robots within production lines. It provides minimum safety requirements that must be respected, as well as specific safety measures to ensure the protection of operators.

Paragraph 5.5 of the standard describes the requirements for the design of machine guards to use in specific scenarios.

According to the standard, machine guards are defined as simple “safety fences” aimed at reducing or impeding the access to hazardous areas. Hence, they can’t be deemed suitable to limit the movements of robots. For them to do so, they must be designed and installed according to requirements defined by a local Risk Assessment and they must keep people at a minimum safety distance from possible hazards.

Identifying the distance at which machine guards must be installed is a complex matter, as it first requires understanding the definition of “operational three-dimensional spaces” defined by the 10218-2 standard.

Additionally, the EN ISO 13857 norm still applies, which details the “Safety distances to prevent the contact of dangerous areas with upper and lower limbs.”

Concerning the height of safety fences surrounding robotized areas, the standard specifies that safety fences must not be lower than 1400 mm from the adjacent walkable area.

The first step in making working areas safe is the filing of the “Risk Assessment” document, which aims at identifying, mapping and categorizing hazards according to their probability, frequency and potential number of people they can affect. What follows is the definition of a set of measures and interventions/operations that are necessary and sufficient to prevent or minimize such hazards.

The installation of machine guards with specific features is one of the interventions highlighted by the EN ISO 10218-2 standard to ensure a distance between machinery operators and industrial robots in order to reduce hazards.

As the impact force exerted by robots moving can be particularly notable, such machine guards must be particularly robust and resistant. Satech machine guards have been subjected to severe dynamic resistance tests from the inside outwards according to the procedure defined in the EN ISO 14120 standard (“Hard body / Pendulum Test”).

Machine safety fences – those specifically designed for the safety of industrial machines and robots – must include specific features, which set them apart from conventional fences used in different scenarios. These are defined by the EN ISO 14120 standard, which details the “General requirements for the design and manufacture of fixed and movable guards.”

Satech safety fences – made by modular panels – have always been designed and manufactured to comply with this particular norm. The electro-welded mesh panels can be both framed and frameless, with the former also coming in mixed materials. Post sport different sections and are easily installed thanks to different clamping systems. Lastly, a wide range of doors and accessories are available, as well as completely customized solutions specifically designed for our customers.