FOCUS ON HYDROFORMING
Image : Shutterstock . com . some key parts of chassis and body in white , even more now with so many electric vehicle projects entering the market . This technology allows us to manufacture lighter parts which have better performance and stiffness , because its application transforms different sections along the length of the tube .”
A flexible choice
Hydroformed parts and profiles .
Due to the decreased friction and absence of rigid tool contact , sheet hydroforming creates blemish-free formed parts with smooth surface finishes that do not require additional finishing operations , such as polishing or buffing . Process capabilities for precision fabrication of contoured and flat surfaces and the utilisation of exotic materials also reduce the number of surface imperfections requiring further finishing . By minimising the amount of finishing operations required , the hydroforming process decreases production costs .
Tube hydroforming
Tube hydroforming ( THF ) is a cold forming process to form a hollow part with different cross sections along its length by applying an internal hydraulic pressure and forcing the tubular blank to conform to the shape of a given die cavity . It is a specialised type of coldforming technique that uses a high-pressure hydraulic fluid to press tubes into a die at room temperature . This method makes it possible to manufacture hollow components with a complex external shape and especially favourable strength properties .
“ Tube hydroforming is extremely advantageous because it allows manufacturers to create precise replications of the same part without needing to weld or join the two halves of the tube . Hydroforming also leaves the part with a high-quality finish that reduces the need for most secondary processes . The parts can be as thin or as thick as the design demands , and it can have complex joints , threads and formations ,” commented spinning and hydroforming specialist , Helander HQ + Forming in the U . S .
Tubular hydroforming is used when complex components , such as curved sections , are needed . Examples include truck / car door handles and bicycle frames etc . Other benefits include greater rigidity and strength of tubing ;
lower weight ; the integration of multiple manufacturing steps ; fewer joining operations ; high repeatability and the production of complex geometries .
“ The main advantage of hydroforming is that it allows complex shapes with concavities to be formed , which would be difficult or impossible with standard stamping ,” commented stamping specialist , Gestamp . “ Tube hydroforming technology is vital for
Image : Helander .
Hydroforming technology is well suited to structural items , from small and shallow to large and deep parts in various materials ( such as aluminium alloys , stainless steel and titanium ). It is used , for example , for engine components including deep-drawn parts in high-strength , heat-resistant materials . It is also employed for the expansion forming of tubes , ducts and other irregularly shaped parts .
Complex , close-tolerance parts can be produced , often in one operation . The process also offers higher productivity levels , as multiple parts can be processed in a single cycle . Faster lead times also result , with quick tool set-up .
If electrodes are used to vaporise the fluid explosively in an arc , this describes a similar process known as electro-hydraulic forming . For large parts , explosive hydroforming can generate the forming pressure by simply exploding a charge above the part ( complete with evacuated mould ) which is immersed in a pool of water . The hydroforming-into-a-mould process also works using only a shock wave in air as the pressuring medium .
“ Hydroforming ’ s broad design freedom ; high material utilisation ; reduced part weight ; high mechanical strength and improved dimensional accuracy contributes to its popularity as the chosen manufacturing method for many industries such as automotive , lighting and appliance industries ,” concluded Metalcraft Spinning and Stamping . n
Image : Shutterstock . com .
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