Knowledge Base

Digital Inventory

Inventory and inventory management is an important aspect of the manufacturing sector, especially the automobile, machinery, consumer goods, aerospace industry, etc. The term ‘inventory’ means the act of counting and listing items. These items can be raw materials, components, work-in-progress items, finished goods and allied material. ‘Inventory management’ refers to the practice of stocking just the right amount of stock at the right time and the right place. For example, when automobile manufacturers come out with a new model, they need to stock certain items. Say there is an issue with the gearbox of a new car for whatever reasons. The manufacturer cannot tell the customer to wait for six months as the next batch of gearboxes will be scheduled for production then. So, the auto manufacturers have to have some crucial items in their inventory. The same is true for aeroplanes as well. To be profitable, an aeroplane needs to be flying almost incessantly, stopping only for essential maintenance. Aeroplane tyres need to be changed after every 100 – 150 flights, depending upon the landing and take-off conditions. If the tyres are not replaced as soon as the need arises, the airliner simply cannot sustain the losses incurred as the aeroplanes will be grounded. However, keeping too much inventory is a risk too, as it eats into the profits of a company. Unfortunately, there is no hard and fast formula that can predict exactly how much inventory is enough. So, managing inventory is a very tricky question, especially in the auto and aerospace sectors. Stacking too many parts not only reduces profits; it also takes up precious warehouse space. In today’s pandemic-hit times, when everyone is striving to be lean in order to survive, keeping inventory to the barest minimum is the need of the hour. Luckily, digital inventory has managed to do just that.

What exactly is digital inventory anyway?
To understand digital inventory and its importance for the manufacturing sector, let us just quickly recap what 3D printing is.

3D printing is the process of building up an object from files designed on a computer. 3D printers create an object by layering two-dimensional cross sections sequentially, one on top of another. For this reason, 3D printing is also called additive manufacturing (AM). 3D printers can create a wide range of shapes, sizes, and types, but in essence they are all computer controlled additive manufacturing machines. There are several 3D printing technologies available, but the additive manufacturing process is essentially the solidifying or binding of a liquid or powder at each spot in the horizontal cross section where solid material is desired.Manufacturers, especially those from the automobile and aerospace sectors make extensive use of 3D printing as they can turn out metal as well as plastic parts that can be directly utilized as the end product. With more and more players entering the fray – from established world leaders like Stratasys to newbie companies that have just started manufacturing 3D printers  - the 3D printing of today continues to be better, faster and cheaper than the printers of five years back. More importantly, they can be used to directly print a spare part without going through different processes like milling, grinding, etc.

Coming back to digital inventory, we have already noted that a physical part occupies space and consumes raw material. If an excessive amount of spare parts are stored and never utilized, it results in a loss for the company. However, if a customer does not get a spare part on time, the company can lose the customer. Digital inventories are nothing but computer files of products, spare parts and components that can provide 'on-demand' real products. These computer files are CAD drawings of parts, ready for direct 3D printing. They are stored as STL, OBJ, AMF or 3MF files, which are some of the most common 3D printing formats.Digital inventory unlocks the possibility to store some parts virtually instead of maintaining large physical inventory. With proper implementation of a digital inventory, manufacturers have ready access to a component via its design files that can be 3D printed as needed. And since most automobile and aerospace companies now have high end 3D printers like those from Stratasys, printing a part is really easy. By integrating digital inventory with the existing ERP system, it is literally possible to print a part at the single click of mouse - no need for time consuming tooling! Digital inventory therefore results in an entirely digitised workflow, using software to control the entire inventory process.

One leading software tool that has data management capabilities is PTC Windchill. That helps companies store, sort, and maintain digital repositories of design data that can be accessed any time for reference and use. Windchill also helps companies in resource management, cost management, change management and process management besides product data management.

Benefits of Digital Inventory
Digital inventories provide many benefits to the manufacturing sector.

  1. Instant access to part design: Since the parts or components are saved as CAD files along with their order and production settings, it is very easy to print them. There is no need for any highly skilled workmen to manufacture the part; any part that has been defined properly in the digital inventory can be printed repeatedly without loss of quality.
  2. Saving on warehouse space:  Physical inventory consumes a lot of space. Before digital inventory, companies typically stored their spare components in a remote warehouse so as to reduce rental costs. In case a customer ordered a spare part, the list was sent to the warehouse, and it was dispatched from there. With 'on-demand' printing using additive manufacturing (3D printing), there is no need to store all the components.
  3. Improved logistics: Digital inventories improve logistics. Let us suppose there is an automobile company headquartered in Germany and having presence in India and Singapore. Say a customer in Singapore needs new brake ducts for his or her car. Since manufacturing spares is cheaper in India as compared to Singapore, the company would prefer sourcing it from India. But with shipping costs and import taxes, the logistics does not work out. With 3D printing and digital inventory in place, this is no cause for worry. Once a customer places an order, the brake ducts can be 3D printed using just-in-time technique irrespective of whether the customer is in Singapore, India, Germany or anywhere else.
  4. Ensuring spare part supply: After a certain time, it is not mandatory for companies to provide spares. For example, as per the existing laws in India, an automobile manufacturer is not required to supply spares after 10 years or so after a model is discontinued. In some cases, companies go bust and it is just not possible to procure spare parts. An otherwise excellent vehicle will be useless for want of something as simple as a spark plug or clutch. This might leave customers in the lurch. With proper digital inventory, making a spare part available will not be a problem, irrespective of the time elapsed.

Of course, as of date there are limitations to digital inventory. The most important constraint is that not all parts can be 3D printed. A physical inventory is needed for these parts. However, with improved technology, the 3D printers of tomorrow will be surely able to print an increased number of components, and digital inventory will continue to play an important role in transformation of a company’s digitization process.