How will the electric vehicle revolution change machining for OEMs and suppliers in automotive?
The electric vehicle revolution has gained unstoppable momentum, initiated by trailblazers like Tesla, BYD and various other electric vehicle (EV) first adopters. Internal combustion engine (ICE) powered vehicles will soon be seen as an outdated technology, with some estimates predicting over 50% of all passenger cars will be electric by 2040. It’s no surprise that many companies are lagging behind the initial success of companies like Tesla and BYD. The resistance to change is however not due to stubborn ignorance but rather it is the decades of accumulated equipment for machining automotive parts, logistics networks, etc. that has gone into building their various production capabilities. This represents an incredible amount of invested capital that cannot simply be discarded.
These companies are a metaphorical large ship with a small rudder and need time to re-tool and change course from ICE to EV. This article will focus specifically on the sectors involved in machining automotive parts in these companies, and how the change to EV will affect them.
Machining automotive parts in an ICE factory
Internal combustion engines are notoriously complex. This complexity stems from the need to convert chemical energy to mechanical advantage. This power then needs to be changed from a linear force to a rotational force in order to turn the wheels via the transmission. The complexity does not end here however as the engine must be kept cool, power must be transferred to the wheels at different torque and speed combinations, etc. The vast majority of the parts in an ICE vehicle are made from metal and therefore need to be machined at some stage in their manufacturing process.
Machining automotive parts in an EV factory
An EV is significantly less complex in terms of moving parts. An electric car has 3 main components, namely an electric motor, a battery pack and a transmission. The battery pack has no moving parts and the electric energy is extracted via a chemical process which then powers the motor. The motor then transfers power to the wheels by making use of a small transmission, typically a single speed transmission as is the case with Tesla vehicles. This means that the overall requirement for machining automotive parts is much less than an ICE factory.
EV Machining Requirements
OEMs and their suppliers will need to evolve alongside the market drive towards electric vehicles. This will require shifts in the components being made as well as how they’re made. Listed below are some of the requirements in the EV industry for machining automotive parts and areas of focus.
- Battery manufacture – Battery manufacture will be the bottleneck of future EV production. Tesla anticipated this and is planning on mitigating this effect by constructing battery manufacturing hubs called gigafactories. Car companies will need to wade into battery production as the market is already strained with limited worldwide EV adoption. BYD has also undertaken the manufacture of battery packs. Battery production is no trivial task and requires precise manufacture only achievable with advanced CNC mills, lathes and grinders.
- Power-train manufacture – Power trains for EVs are far less complex than a typical ICE power train. OEMs and their suppliers will be able to transition to the manufacture of these drivetrains with minimal changes to their existing machines and processes, albeit at a smaller production volume.
- Body panels – These panels are created by stamping or drawing sheet metal into the required shape by means of a die to create the complex forms of modern passenger vehicles. The dies used for this process are machined using 5-axis machines. This process will not change once manufacturing transitions to EV vehicles.
- Higher quality – Due to the relative simplicity of EVs and the resulting low maintenance requirements, the focus will shift to producing parts of a higher quality. In order for machined parts to last as long as the electric components of an electric car, they need to be manufactured with machinery that can meet the accuracy and repeatability required.
- Lightweight – EVs are very sensitive to excess weight, therefore parts need to be manufactured from lightweight aerospace materials. Parts will also be designed using optimisation technologies like generative design and topological optimisation. These complex parts will require more time to manufacture than traditional automotive parts due to the complex organic shapes that are a result of these algorithms.
- Low noise – EVs are quiet by design. However, the immersion is broken if there is excessive noise from poorly machined parts. One of the easiest ways to achieve the surface finishes necessary to reduce noise is to use purpose built grinding machines that can achieve the tolerances required.
Looking to the future
As consumer demand for EVs continues to rise, OEMs and suppliers will need to transition towards production lines that are appropriately designed, even more aggressively. The general trend will be a vastly reduced metal-part count but an increase in requirements for higher quality surface finishes and tolerances with increased part complexity when it comes to machining automotive parts. Businesses supplying OEMs in the automotive industry will need to diversify their client base, and look to other industries to ensure that there is not a catastrophic loss in production capacity.