The ATEX factor

15 February, 2017

In many cases, especially in larger facilities, working towards a decentralized system of process control can provide a number of benefits compared to the more traditional approach. This concept uses intelligent, pneumatically operated process valves at the field level which can be equipped with all the required automation components such as a pilot valve with manual actuation, electrical feedback units and optical status indication, field bus interfaces and even positioners and process controllers.

To bridge the gap between centralised and decentralized automation concepts, flexible pneumatic valve units and compact automation systems can be used. These units are typically wall-mounted directly inside small cabinets that can be installed close to the process in question. These small, pre-configured and standardised units eliminate the long runs to valves and field devices, and can be maintained easily.

Each and every client will have a unique scenario that requires the manufacturer of the control panel to take a very individual approach to the project. At Bürkert, a network of specialist design and manufacturing facilities, known as a Systemhaus has been in operation for several years. Their purpose is to deliver precise fluid control systems designed to meet very specific process requirements and regulatory standards.

The Menden Systemhaus maintains a very high level of expertise in delivering control cabinets for installations in potentially explosive atmospheres. From initial concept to on-site commissioning, a dedicated team is assigned to each project to ensure continuity and understanding of the project requirements are maintained.

Due to the multiple competencies within each team, it is possible to design compact, integrated solutions that often contain both electrical and pneumatic circuits and even fluidic connections as well. In this way, it is possible to deliver a single control cabinet, minimising space requirements as well as all the equipment that will deliver the process control itself, which reduces commissioning time and improves final delivery.

Very often the theoretical design of a control cabinet for a zoned area is the simplest task, finding the components that will deliver the design in reality while also meeting the required ATEX or IEC-Ex standard can be more difficult. This is especially true for electro-pneumatic automation systems that are designed for installation in Zone 1, a product that is only available from a select number of manufacturers.

This system is particularly suited to decentralised process control tasks concerning fine chemicals, pharmaceuticals, cosmetics and oil & gas; it can be used for example to automate the filling of potentially volatile solvents, alcohol or lacquers. In these application areas, it is necessary to have a compact electro-pneumatic automation solution allowing integration of EEx ia rated pneumatic valves without additional wiring.

Systems such as this can only really deliver the expectations of the client if they are conceived, designed and manufactured by a single, dedicated team with the experience to appreciate the fine detail involved. Ideally, a dedicated team is assigned to each project, from initial concept to on-site commissioning, to ensure continuity and understanding of the project requirements are maintained.