Safety is always a key consideration in any environment where manufacturing processes or machinery are involved. This topic is even more critical within industries such as petrochemical, refining and mining, where there may be potentially explosive atmospheres. In these critical areas a single spark may be all that is needed to trigger a potentially catastrophic series of events. The European Union’s Atmosphere Explosibles (ATEX) Directives, introduced in 2003 are intended to reduce the hazards created by potentially explosive atmospheres.
There are two distinct directives: the first ATEX 95, applies to the design, manufacture and in-service use of equipment within potentially explosive atmospheres. The second directive ATEX 137, sets out the minimum requirements to improve safety and protect workers from explosions. This places specific requirements on employers for risk assessment and implementation of measures to reduce explosion hazards.
As a key component in any drivetrain being used with a hazardous environment, drive couplings must adhere to the ATEX 95 directive. Reich’s Multi Mont Sella range not only meets the directive requirements and is certified, but the design of these drive couplings also incorporates features that further enhance the fail-safe characteristics of the coupling.
In addition to compensating for axial, radial and angular misalignments, shocks and vibrations, these couplings are designed with individual rubber compound saddles. This means that even if one or more of the saddles begins to deteriorate in service, the unit will still operate safely, minimising the risk of metal-to-metal contact and any subsequent sparks. Although the coupling may exhibit signs of reduced performance, giving maintenance engineers the time to plan remedial work, the coupling will still operate safely.
A further benefit of the range is that the rubber saddles can be replaced radially with the coupling in situ, by simply sliding back the retaining cap, saving significant amounts of time by eliminating the need to de-couple equipment.
ATEX 95-compliant couplings
Also certified for use within hazardous environments is the Arcusaflex range of couplings. These also comply to explosion protection directive ATEX 95, and are suitable for use within hazardous location categories M2 and 2 which require high levels of protection, and 3 which requires normal levels of protection.
The Arcusaflex coupling is a highly flexible flywheel coupling with an axial plug-in facility. It provides a torsionally soft connection between the prime mover and the driven machine. The highly flexible torque transmission characteristic of the coupling is achieved by a disc-shaped rubber element that is subjected to a torsional load and enables both, the absorption of high torsional vibrations and the compensation of major misalignments. The toothed design of the rubber element is instrumental in maintaining safe operation within hazardous environments. Reich has built up vast expertise in the design and manufacture of drive couplings for use across a wide range of industries and applications, including those within hazardous environments.
David Proud is general manager of Reich Drive Systems UK.