How safe is your electrical enclosure?
01 March 2010
When it comes to selecting the right electrical enclosure for hazardous area applications, choosing a manufacturer that is in total control of its product quality on a global basis is all-important. We discover how one successful company has achieved this essential aim
Cooper Crouse-Hinds (CCH) manufactures a wide range of enclosures for hazardous areas and general industrial applications at its manufacturing plant in Sheerness, Kent. The company is now the single largest user of type 316 stainless steel in the UK electrical industry, processing around 600 tonnes of the material each year for its enclosures.
For CCH’s Sheerness plant, customisation is the standard. Some 70% of its output is specific to the customer and 80% of production goes to export. Batch size is not a problem and the company has gained something of a reputation for never saying “no” to an order, no matter how small.
Perhaps one of the key factors behind this flexibility is the company’s complete control of its manufacturing process, from enclosure design and fabrication, through to electro-polishing, powder coating, assembly, quality and despatch - and the label says ‘made in the UK’ which is very important to some of its customers.
The Sheerness plant is not highly automated but instead prefers to rely on the craft skills of its 90-strong workforce. “Each enclosure is essentially hand crafted,” says operations manager, Richard Gipp. “Our plant is a model lean factory and so we never make-to-stock. Every enclosure is made-to-order and we are therefore agile and flexible when it comes to supplying customers. We’ve even been asked by our regional manufacturing advisory service to show local manufacturing firms around the plant, in order to help them visualise what a genuine lean manufacturing operation looks like and to learn from us.”
The Sheerness plant also prides itself on design innovation. The latest enclosure for hazardous dust and gas applications is the Ex-Cell range of ATEX-certified stainless steel heavy-duty enclosures (see panel story). With Ex-Cell, the customer gets to choose from a wide variety of service fittings, including terminals, cable glands, breather drains and blanking plugs. And if the customer requires it, the enclosure can be populated with control hardware, including measuring devices, instrument transmitters and fieldbus modules.
“There are thousands of different options on the Ex-Cell enclosure, including window kits, a padlockable hasp, pockets for CAD drawings or rain canopy,” says Mr Gipp. “We can even provide special sloped or flush mount versions and large enclosures with double doors for protecting PLCs, large displays, air conditioning systems and fans. These are ideal for food and dairy producers, waste water treatment and harsh environment wash down applications.”
An ‘Ex-Cell’ent design innovation
The Ex-Cell enclosure is mounted via four heavy-duty, 3mm thick surface welded stainless steel lugs, the bottom set being slotted for ease of mounting. An integral drainage channel prevents liquids or other solid contaminants from running in or falling into the enclosure when the door is opened, which minimises gasket path contamination. The enclosure is available with up to four gland plates (3mm thick) on each side and enclosure sealing is IP66 rated, thanks to a high integrity Chloroprene gasket and a securing arrangement comprising ‘Hytork’ fixing bolts.
The standard includes a quarter turn keyed lock fastening mechanism and a bolted cover and padlock option are also available. The enclosure is also supplied with an external and internal feed-through brass earth/ground stud assembly, which enables a rapid and reliable protective earth connection to be achieved. This is mounted on the side of the enclosure for ease of access.
Contact Details and Archive...