The use of robotics in industry is widespread, with new applications emerging continuously. If the robotic arm system is to be located in a hazardous area, then a certified solution is required to ensure safe operation.
Due to operational requirements and constraints, many of the possible Ex protection concepts are not suitable. Ex p (Purge & Pressurisation) provides a flexible and cost-effective solution.
The customer required Ex p solutions to be developed to deal with a range of robot sizes. Although there were physical variations between the robotic arms, a single solution was proposed that would be able to deal with multiple pressure set points and purge flow rates. Expo selected the MiniPurge system due to its global certification and flexibility in flow rates. This allowed one system to suit the full range of customer robot model sizes.
The additional challenge of purging a remotely located system meant that the MiniPurge system had to be fitted with a return air line and local "enclosure". The Expo system was then effectively purging two enclosures in series, firstly the robotic arm and then the local "enclosure" where pressure and flow could be monitored.
The use of Ex p meant that only small changes were required to the standard IP 65 robot arm design. Standard stepper motors and controls could continue to be used, significantly reducing the costs of arm manufacturing.
Expo has also carried out similar projects, adapting the SmartPurge II platform to deal with the specific flow rate requirements of this type of application.