🏭Manufacturing

Discrete Manufacturing

Discrete manufacturing is the creation of products that can be easily differentiated: products you can touch, such as cars, books, toys, furniture or electronics. Discrete manufacturing is not continuous, meaning production can start and stop as demand requires.

The process involves creating, assembling and handling individual components to make a product. Discrete products are easily counted and measured in units, as opposed to process manufacturing products (such as Oil, Food) that are measured by weight or volume. Assembly robots are commonly used in discrete manufacturing.

Process Manufacturing

Process manufacturing involves using formulas, much like recipes, to take a set of raw materials to make a final product. Examples of process manufacturing include oil refining, chemical refining, food and beverage production and pulp and paper production.

Process manufacturing is different from discrete manufacturing because once the final product is produced from it's individual elements, it cannot be taken apart to get them back. Within process manufacturing, there are 3 types of process: continuous, batch and hybrid.

Continuous Manufacturing

Continuous processes require an uninterrupted flow of material from start to finish during the transition from a raw material to a finished product, such as the process used to make chemicals. Generally, a continuous process runs constantly unless interrupted by an unscheduled outage, usually caused by an emergency or equipment failure.

Continuous processes may be shut down for scheduled maintenance, sometimes referred to as turnarounds. Turnarounds are used to keep refineries running in a safe operational state; however, not every sector has scheduled maintenance periods. The turnaround time will vary between sectors.

The ICS used in continuous processes must be flexible to control all phases of the process: from startup, to continuous operations, to emergency shutdowns, to maintenance shutdowns. During continuous operations, such as in a refinery, the ICS is constantly adjusting the valves and pumps to keep the process within specifications.

Batch Manufacturing

A batch process has a starting and ending point. Batch processes are similar to cooking, in that you have a list of items or ingredients and a procedure (recipe) consisting of a series of steps for mixing the various components to create a product. As one phase of the batch is finished, the system will transition to another phase of the batch process. Pharmaceuticals and specialty chemicals rely heavily on batch automation to create their products. Many batch manufacturers will procure a batch management system that is used along with the control system. Batch management systems work with the control system to execute batch processes. They are also used to manage recipes and records. Records management is especially important in regulated industries where the operators are required to audit the batch process.

Hybrid Manufacturing

A hybrid process uses a combination of continuous and batch controls. Water treatment is a good example of a hybrid process. Water flows through the treatment plant where disinfectants are injected into the water to kill bacteria. The chemicals cause particles to clump together, where they are removed through sedimentation or filtration.

For the most part, water treatment is a continuous process as it flows through the pre-treatment, filtration, and post- treatment processes. However, as solid particles build up in the filters they need to be flushed. This is typically done through a process called backwashing. Backwashing uses batch control to automatically operate valves and pumps in a series of steps to reverse the flow of water through the filters to remove the particles.