– Manufacturing as a Production Vs. Manufacturing as a Service –
In parts 4~5 of this series, we explored the shape of manufacturing systems and virtual and physical manufacturing systems as well as the entities that make up manufacturing systems and the relationships between them. Today we will discuss types of manufacturing, the operational technology that covers the various types of manufacturing and the role of IT in hardware-software interfaces.
- The Role of IT in the Interaction between ‘Me’ and ‘You’ (Part 4):
- The Role of IT in the Interaction between ‘Me’ and ‘You’ (Part 5):
What is Produced and How it is Produced: Discrete Vs. Process Manufacturing
There was once a time when people thought, ‘if the product is good, then all is well.’ But this idea has changed drastically. Similar to Moore’s Law, as the products manufacturers are producing more complex, the facilities and systems used to produce these products are becoming bigger and more complex as well. When an unforeseen internal issue occurs one of these expanded systems, it can be difficult to completely understand and manage the issue. The consumers of these days are also quickly becoming tired of new products and are fussier when searching for a smart product. This trend is even interfering with the development and value chain of products.
Even with the advent of IoT (Internet of Things), the current situation for channeling and managing the information surrounding the manufacturing systems of today has not been improved through the phased introduction of each automated system is still not good. This is because there are many problems that need to be resolved that are scattered throughout systems like islands in the ocean. So, in this current situation, what are manufacturing systems and producing and how are they these products produced?
Above, we mainly discussed ‘discrete manufacturing’ products. However, there are many different manufacturing methods and systems according to the type of product being produced and there are also different processing methods and structures such as ‘process manufacturing’, ‘repetitive manufacturing’ and ‘hybrid manufacturing’. Take a look at the chart below.
By looking at the chart above, we can see the differences between discrete manufacturing and process manufacturing. There are differences that occur in the characteristics of each core entity and the relationships between these entities and control methods are also different. We can see the classification that increases productivity through more efficient methods according to each product and industry.
We will now take a look at discrete manufacturing and process manufacturing through the 2 examples referred to earlier in this series. These 2 examples are the ‘doghouse assembly process’ and the ‘mother’s dinner making process’. These examples are quite simple and limited to household handiwork but the first example gives us an idea of discrete manufacturing and the second example shows us how a combination of discrete and process manufacturing work together.
1. Basic materials such as lumber and other connecting components are prepared as specified in the BOM
2. Each component (front panel, side panels, floor, roof etc.) is cut and surfaced.
3. Connecting/fastening components such as nails or screws are used to assemble the parts and the product is completed.
1. The ingredients are cut and sliced and the appropriate amounts ingredients are prepared according to the recipe. (discrete manufacturing)
2. Boil the appropriate amount of water in the pot. (measuring tools do not have sensors so the amount of water and the amount the water is boiled must be gauged by sight)
3. The ingredients are added according to the formula/recipe (depending on the cook).
4. As the water boils, the concentration of ingredients and the flavor are checked and the cook determines when the process is finished. (intuitive decision)
When we compare these examples, we can get a clearer picture of the differences described in the chart above. The biggest difference is that actions (ex. the saw cutting the wood) can be more precisely separated in example 1, whereas the actions in example 2 are less clearly defined. In this case it is difficult to clearly separate detailed processes or steps in a process. There is not a specific standard or order for ‘adding salt’. Of course, through the process of tasting the food, adding salt can be measured and the process can be completed. So when someone cannot taste the food directly or there is no sensor to distinguish the taste of the food, variables such as time, water temperature, pressure and concentration must continue to be checked. It can then be determined when a process is finished or the next process should begin.
In the image to the right above, we can see a process flow pant manufacturing process. Reaction equipment and equipment that separates and refines the product move the materials internally to make the product. While each piece of equipment has various controls, various pieces of equipment are connected (ex. the product in Device 3 is moved by pipe to Device 1 and moves from Device into Device 2) moves and a control is needed to ensure that each instrument is controlled and the entire process runs smoothly.
In this way, the goal of discrete or process based mass production or multi-production systems is to ensure management of processes without disrupting the process flow. Production is begun and finished in the appropriate order according to defined events and rules so that the next product process flow can be prepared (controlling the set up of a mold). This information is the foundation for resources that improve productivity and efficiency throughout the administration of an entire factory.
We have now taken a look at the differences between discrete manufacturing and process manufacturing.
Written by SeungYup Lee
Finished his doctorate at Pennsylvania State University and is now working as a researcher. Received his masters in industrial systems engineering at Yeonsei University his doctorate in industrial engineering at Pennsylvania State University. Is currently focusing on Formal model based hybrid SoS engineering, Diverse Simulation based methodology (agent, discrete event, system dynamics), manufacturing and supply chain systems, IT-based industry convergence and Cyber-Physical System .
 Repetitive manufacturing is a method used in discrete and process manufacturing for the continuous production of high volumes of one product such as in a in a car production line, packaging, electronics and consumer packaging. This method is used primarily in make-to-stock strategy for manufacturing.
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 Source: ‘Automated Control?’, Tsujiro Shimemura (1994)
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