Re: Meco Seals For Atex Applications
Could you clarify your comment :
"The directive considers packing glands unsuitable for service in potentially explosive atmospheres"
I was not aware of this, could you give us the particular reference and quote from the directive that says that packed glands are unsuitable ■
Re: Meco Seals For Atex Applications
I'd also like to see this.
It's interesting to see how the directives are interpreted by different companies. ;-) ■
Re: Meco Seals For Atex Applications
EN 13463-5:2003
4.4.2 Stuffing box seals
Stuffing-box seals shall only be used if a temperature rise above the maximum surface temperature can be excluded.
Stuffing box seals permit unlimited operator adjustment. Such adjustment increases friction and thus operating temperature at the seal interface, thus the referenced temperature rise cannot be excluded. The use of thermal monitoring/shutdown equipment can permit the use of stuffing boxes on Group II, Category 3 equipment, but potential failure of the monitoring/shutdown system makes stuffing boxes unsuitable for Category 2 machinery.
Specification of water or another coolant subjects the seal to EN 13463 Annex B testing, which requires that the seal meet the standard without lubricant. ■
Re: Meco Seals For Atex Applications
Must check our information and see if it's current. ■
Re: Meco Seals For Atex Applications
Thanks for the reference, I have seen stuffing boxes on items of equipment from other manufacurers.
Would their argument be that a stuffing box can be used as long as the melting point of the packing material (typically PTFE) is less than the minimum surface temperature of the potential explosion hazard? ■
Re: Meco Seals For Atex Applications
Originally posted by RPD
Would their argument be that a stuffing box can be used as long as the melting point of the packing material (typically PTFE) is less than the minimum surface temperature of the potential explosion hazard?
It's all down to the risk assessment. Maybe those who use stuffing boxes have measured data that they can use in their risk assessments rather than relying on speculation and conjecture about what "may possibly" happen which appears all too often.
Anyone got any data on the incidence of dust explosions caused by stuffing boxes? ■
Re: Meco Seals For Atex Applications
We have tested various seals for Atex certification and maximum temperature rises is measured in case of a failure. As RPD has already mentioned as long as the temperature doesn’t rise above minimum surface temperature they are good. ■
Meco Seals for ATEX Applications
In 2005, the European Union's ATEX Directive (EN 94/9/EC) went into effect, governing all industrial environments containing potentially explosive atmospheres. (The name comes from the French: ATmosphres EXplosives.) Examples of sites under the jurisdiction of ATEX are those where dust or vapors are present in contained or concentrated atmospheres, such as processors of hydrocarbons or dry powders.
Bulk processors in Europe have been obliged to review their equipment, including shaft seals, to ensure compliance with the ATEX Directive. The directive considers packing glands unsuitable for service in potentially explosive atmospheres, so many processors are seeking ATEX-conforming alternatives.
MECO have responded by investing significant research and development resources, adapting two of their seal designs so as to comply with this mandate for their customers. MECO seals are now available for certain European explosive atmosphere applications in Equipment Group II, in Categories 2 and 3.
Processors seeking ATEX-compliant sealing solutions find that some seal manufacturers claim ATEX compliance, while in fine print they require water purging or limit dry-running compliance to an impractically narrow range of operating parameters.
MECO designers, in keeping with their tradition of custom-engineering each seal, examine every ATEX application individually and arrive at means of protection which meet both with the ATEX Directive and with the processor's expectations and requirements.
More specific information may be seen at: www.mecoseal.com/atex.php .
MECO seals are manufactured since 1984 by:
Woodex Bearing Company, Inc.
Georgetown, Maine, USA
www.woodex-meco.com
sales@mecoseal.com
tel. +1-207-371-2210
fax +1-207-371-2169
https://edir.bulk-online.com/profile...ex-bearing.htm
Attachments
atex-1 (JPG)
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