MACHINING & MACHINERY DEEP HOLE DRILLING AIDS
UNISIG
By Anthony Fettig – CEO , UNISIG Deep Hole Drilling Systems
The future of the auto industry is interesting but uncertain . No one knows how quickly electric vehicles are going to replace gasoline- and diesel-powered vehicles , how completely it will happen , and when it will occur in passenger cars as opposed to SUVs and heavy trucks . However , we do know that fuel economy standards continue to progress and drive vehicle design toward smaller displacement , higher-technology engines .
As a result , technology that was developed years ago for high-performance vehicles is now becoming mainstream . For example , sodium filled valves , which formerly were used in only extremely high-performance engines to manage heat in the valve train , are becoming more common . The same goes with hollow camshafts , which reduce energyconsuming rotational inertia and provide opportunities for engine management .
Within vehicle drivetrains , today ’ s automatic transmissions now have as many as eight or even 10 speeds instead of five or six . This wide selection of gear ratios enables smaller displacement engines to provide better fuel economy and deliver higher performance .
These kinds of technological upgrades for higher performance and economy are not new , but previously were considered too costly for general use . Now , advanced manufacturing and materials technology make common application of these upgrades viable .
ENABLING COST-EFFECTIVE PRODUCTION
Deep hole drilling is one advanced manufacturing technology that allows for the cost-effective production of key features of those performance-boosting parts . Sodiumfilled valves , for example , have holes drilled the length of the valve stem in which liquid sodium circulates and draws heat from the valve head . Precise deep hole drilling methods enable hollow and more energyefficient camshafts to be manufactured . Complex multi-speed transmissions feature shafts with multiple off-center holes of varying depths for lubrication or hydraulic sequencing . The holes in the shafts are too deep to produce effectively on machining centers , so deep hole drilling machines are critical in those instances .
BALANCING VOLUME OUTPUT WITH FLEXIBILITY
Other manufacturing challenges in automotive production can also benefit from today ’ s advanced machine tool technology . For decades , the automotive industry focused nearly exclusively on volume production . The emphasis was on making as many parts at the lowest cost possible . Flexibility was merely a minor consideration .
Market changes have made balancing volume output with flexibility a major issue . If volume drops on a vehicle program , there remains a need to produce the vehicle cost-effectively . Expanded product mixes created to meet customer desires for different powertrains and other options demand high efficiency regardless of volume .
Consequently , flexibility and spindle utilization have become the main drivers of deep hole drilling machine design . Instead of having a gang of four spindles pounding out parts , a two-spindle machine with a rotary table and X-Y positioning system can provide extremely high spindle utilization along with flexibility . Technology such as automated setup through servo motion to reduce changeover time is also considered in the early concept development of the machines . These systems allow manufacturers to plan and implement small , agile cells to replace large , old-school , high-volume systems .
BENEFITS OF MACHINE AND FIXTURE DESIGN
A recent customer experienced significant benefits with UNISIG ’ s machine and fixture design . Previously , the customer was processing a challenging family of parts on a system that involved nearly 20 fixtures . Each part required multiple holes with varying depths and diameters . A bulky , dedicated machine created an unnecessary expense and bottleneck in their production .
UNISIG provided a machine that allowed the company to manage deep hole drilling of these parts with just two pallet-changeout
www . unisig . com type fixtures , and requiring only the selection of a new part program . By eliminating fixturing , setup , and programming time , the company experiences significant savings every time the machine runs .
LIGHTER YET STRONGER
In addition to production benefits , a future opportunity for automotive manufacturers that involves deep hole drilling technology is in making vehicle parts lighter yet still maintaining or even increasing their stiffness and strength . Deep hole drilling can produce thin-wall parts such as axles and power transmission shafts , for example , that provide significantly higher mechanical integrity and better improved energy economy .
For instance , drilling a 20-mm axial hole through a heavy 30-mm diameter shaft makes the shaft much lighter while maintaining its stiffness . This lighter shaft has less rotational inertia which , in turn , reduces energy consumption . Designers continually search for such small gains in efficiency and will seek ways to enhance lightness and stiffness throughout the automobile .
As machine tool manufacturers , our job is to listen to our customers , understand what they need , and develop those needs into a solution that is viable from a cost and reliability standpoint . With ongoing advancements in engineering technology , machine manufacturing , and service , what might have been very expensive to do only three or four years ago is now viable . Concepts that once seemed a bit far-fetched are now quite common .
Because of that , we design our machines to provide both flexibility and utilization that will enable our customers to successfully face the expected — but not yet fully known — major changes in the automotive manufacturing industry .
Further information on all machines and the complete UNISIG machine program is available on our website or follow the company on LinkedIn and Twitter (@ UNISIG ). You will also meet us at the EMO 2023 show in Hannover , Germany from 18 .– 23 September 2023 .
70 PECM Issue 59