Dealing with pressure 25 February 2019

By Gail Friedberg, vice-president, ZAGO Manufacturing Company

Engineers are often unclear about the utility of self-sealing fasteners versus ordinary screws, nuts and bolts. Why use a more expensive sealing fastener when a standard fastener or a non-grooved fastener with an O-ring or washer will do? The reason – pressure.

Pressure is everywhere. Even at sea level atmospheric pressure is equal to 14.70 pounds per square inch or 1.03 kilos per centimetre. Inside equipment, particularly hydraulic and pneumatic equipment, pressure rises quickly after activation. Similarly, as an aeroplane rises in the air, outside pressure increases; and as a robot dives below the surface of the sea, pressure increases precipitously. Standard fasteners simply cannot withstand this pressure. Leaks of gases and liquids are sure to follow, leading to equipment failure and environmental degradation. A mechanism is necessary to counteract this pressure.

The best possible mechanism to prevent leaks due to pressure, and the infiltration or egression of liquids and gasses, is a fastener with an O-ring and a groove. Using a simple O-ring or washer to seal, without a groove calculated to relieve pressure, will inevitably lead to equipment failure. However, a accurately engineered groove will absorb the pressure within and outside of equipment that is applied to the O-ring forcing the O-ring to spread and penetrate any open space where leaks might occur.

The demand for sealing fasteners has never been greater. As equipment becomes more expensive and sophisticated, the need to keep it contaminant free is critical. Also, as environmental concerns grow, the need for an environmentally sustainable solution to equipment failure is paramount.

ZAGO self-sealing fasteners are sustainable in the broadest sense of the word. They are conflict mineral free, ROHS and REACH compliant, as well as compliant with California proposition 65. They are the ideal solution for long-term industrial and mechanical sustainability and ideal for sealing electrical enclosures and equipment subjected to the elements. At ZAGO, we are the acknowledged leader in the manufacture of self-sealing fasteners with over 25 years of problem solving engineering experience. To learn more about our clean sealing solutions and components please contact us at info@zago.com

www.zago.com

Deputy Editor

Claire Aldridge Deputy Editor t: +44 (0) 1727 743 889

Biog

Having spent a decade in the fastener industry experiencing every facet – from steel mills, fastener manufacturers, wholesalers, distributors, as well as machinery builders and plating + coating companies, Claire has developed an in-depth knowledge of all things fasteners.

Alongside visiting numerous companies, exhibitions and conferences around the world, Claire has also interviewed high profile figures – focusing on key topics impacting the sector and making sure readers stay up to date with the latest developments within the industry.