ISMR June 2022 - Page 23

FOCUS ON BONDING resistant mouldings and sealing strips .

“ Bearings in various nacelle applications are sometimes mounted in composite components . While composites are generally very strong , it ’ s often a challenge to achieve a tight , long-lasting , dimensionally stable fit between a bearing and a composite structure . Epoxies can be very effectively used to retain and stabilise bearings in such situations , over a wide range of operating speeds and temperatures ,” explained MasterBond .
“ Epoxies can be used during initial wind tower construction and later , when a serviced component is reattached , to keep fasteners consistently tightened to spec . and protected over the long run . Epoxies also make for strong , long-lasting and workable bonds in blade repair , pipe and flange sealing , and electrical / electronic protection and insulation . They can also be used for common tasks such as attaching nameplates , inhibiting corrosion , potting electronic controls and coating electrical connections for both strength and environmental resistance ,” it concluded .
Adhesives for car production
Adhesives are increasingly being used in modern automotive production . They allow different materials to be permanently bonded in an energy-efficient manner and without the need for other auxiliary parts .
Adhesive chemistries include epoxies ; polyurethanes ; methylmethacrylates ; rubber-based anti-flutters ; PVC ; butyls ; bitumens ; thermoplastics and in-component manufacturing silicones .
Adhesive bonding helps to reduce a vehicle ’ s weight , and therefore the CO₂ emissions , of the finished car . It has also proved to be a key energy-efficient joining technique .
“ Not just the car body , but many exterior and interior components , visible or hidden in a car , owe their functionality to state-of-the-art adhesive technologies . Overall , the energy spent per bonding application with adhesives is lower than the energy spent for conventional joining techniques like welding or clinching ,” commented FEICA , the Association of the European Adhesive and Sealant Industry .
“ Adhesive bonding increases the choice of material used and enables more innovative designs ; both are important factors for the safety of the car . For example , the windscreen provides structural strength to the car body and helps keep passengers inside the car if an accident should occur . As important as the windscreen quality is , so too is the quality and proper installation of the auto glass adhesive . The use of adhesives in car production helps to improve the safety standards and allows modern design with innovative material . They help the car industry to meet its challenges of developing more environmentally friendly solutions for the future ,” it added .
Below and bottom : The bonded aluminium unibody of Polestar 5 .
Construction industry applications
According to FEICA , adhesives and sealants present numerous sustainability benefits to the construction sector . When used in the manufacture of construction products or in the construction of a building , they help improve energy efficiency and enable material efficiency through material reduction and the use of more sustainable materials .
“ During the lifetime of the building , they support maintenance , repair and renovation and can thereby increase the building ’ s life span . As evidenced by the high recycling rates already achieved for many types of demolition waste , with the right design , adhesives and sealants do also enable circularity at the endof-life ,” explained the association .
“ As part of external thermal insulation systems , adhesives increase the durability and performance of insulation panels . Polyurethane foams provide insulating gap filling to augment overall insulation performance . Self-adhesive tapes and sealants provide airtightness of insulation systems and windows or glazing elements . Airtightness is crucial for thermal insulation performance , as air leakage can represent up to 50 % of energy losses in a building ,” it added .
Sealants are also key for the energy efficiency and longevity of multi-paned glass elements . Adhesives and sealants can provide these benefits both in new construction as well as in ( energy ) renovation projects . Adhesives and sealants also support the transition to decarbonised heat sources , such as photovoltaic panels , which provide electrical energy for heat pumps , to batteries , which allow storing of surplus daytime electrical energy from photovoltaics , and to solar thermal collectors . n

Polestar 5 bonded aluminium unibody

Bonded aluminium unibody technology does away with the mixed metal structures and the 3,500-4,000 rivets normally used in traditional manufacturing , making use of adhesive and oven curing instead .
The Polestar UK R & D team developed a new method , applying their combined experience from the worlds of Formula 1 and bespoke sports cars to create a process which develops both body and platform in unison .
This combined Polestar 5 platform and body is predicted to weigh less than cars from smaller segments , increasing range and responsiveness while maintaining high safety standards . Additionally , this innovation allows for a high degree of design flexibility , as adjustments for factors like different wheelbases can be achieved .
“ We knew we wanted this car to be lightweight , we knew we wanted high quality and we knew we wanted it quickly ,” said Pete Allen , Head of Polestar UK R & D . “ This architecture delivers outstanding dynamic and safety attributes , with low investment technology applicable to high production volumes .”
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