Environmental Sealing

Environmental Sealing plays a major part in providing the conditions necessary to maintain safety within Explosive Atmospheres electrical systems from the major plant to the interface components. Ingress Protection levels need to be maintained in order to attain a reliable and safely sustained operation.

To maintain the I.P. rating of the equipment and cable gland it may be necessary to fit a Sealing Washer at the cable gland entry interface. For Explosion Protected equipment it is essential to maintain the integrity of the degree of I.P. protection at which the equipment has been rated. The need for a Sealing Washer will very much depend on the I.P. rating and code of protection of the equipment and the type of entry holes available within that equipment e.g. for Ex e apparatus or terminal boxes which are permitted to have untapped through clearance holes it will be necessary to fit a sealing washer to ensure that the minimum IP54 requirement is met for gaseous atmospheres and IP64 for dust hazard environments. Whereas other equipment having tapped entry holes may not require a sealing washer to maintain the rated integrity of the installation.

CMP produce an Entry Thread Sealing Washer in 2mm Thick White Nylon as Standard which are recommended and meet the specified requirements of Shell's Offshore operations. To verify the effectiveness of the CMP nylon entry sealing washers independent 3rd party tests to BS EN 60529:1992 (IEC 529) have been conducted on certain Cable Gland types at IP66, IP67 & IP68 levels of protection. CMP can therefore provide independent documentary evidence of such tests to the highest standards. Red Fibre Washers can also be supplied to order but careful consideration should be given to their use in sub zero climates where absorption, freezing and cracking have been known to occur, ultimately impairing the degree of Ingress Protection attainable.