Manufacturing Process

What is a manufacturing process?

Manufacturing is the process of transforming raw materials or components into finished products. The manufacturing process provides a step-by-step blueprint to develop products.

The two primary manufacturing types are discrete and process. Discrete manufacturing produces parts, components, and products using a combination of defined materials and production sequences to create distinct items and products ranging from smartphones to wind turbines in industries from automotive to aerospace.

The discrete manufacturing process includes a bill of materials (BOM), along with the steps and requirements to produce each part, assembly, or complete product. This manufacturing process includes the materials, machines and tooling, labor, production, assembly, and other requirements to produce products.

By contrast, process manufacturing creates finished products by mixing raw materials and ingredients to create a volume of an end-product (not individual units). Process manufacturing examples include food and beverages, pharmaceuticals, and gasoline.

What are the primary manufacturing processes for discrete manufacturing?

Production methods each have their own relative strengths, and variables for selecting a manufacturing technique include production volume (low production vs. mass production), the functionality of the final product, and associated lead times required to meet customer demand. Additional manufacturing business considerations include inventory management and how finished goods will be distributed.

Here’s an overview of the different types of manufacturing processes:

Additive:

3D printing, also known as additive manufacturing, is a process that creates three-dimensional objects by adding material layer-by-layer until the part is completed (based on a CAD model). Unlike subtractive manufacturing, additive manufacturing builds the product from scratch, presenting unique and highly complex design possibilities. This process minimizes waste because it only uses materials required for construction.

Additive manufacturing is frequently used for prototyping, customized production, and small-scale manufacturing. Additive manufacturing  processes include:

• Direct metal laser sintering
• Material jetting
• Powder metal
• Selective laser sintering
• Stereolithography

Assembly:

Assembly in manufacturing combines individual components or parts to create a finished product. It involves connecting, fitting, and joining parts or components in a systematic way to form a complete and functional unit. Parts and components are assembled manually or via assembly line automation and robotics. Methods of assembly include:

• Adhesive bonding
• Mechanical fastening
• Sealing
• Threaded insert
• Welding

Casting and forging:

Casting is a manufacturing process that involves pouring a liquid material – often molten metal or alloy – into a mold to create a solid object. This method produces components with intricate designs and complex forms that would be challenging or costly to create using other production techniques. Typically used for high-volume production, casting and forging methods include:

• Closed die forging
• Die casting
• Investment casting
• Ring rolled forging
• Sand casting

Composites:

As the term implies, composite manufacturing combines two or more materials into a single part or component. Common composite material types include carbon fiber, fiberglass, metal, and reinforced concrete. For example, Metal Matrix Composites (MMCs) could include a metal such as aluminum reinforced with a carbon fiber). Composite materials are designed to be lighter and stronger than comparative materials. Composite manufacturing methods include:

• Additive / 3D printing
• Automated fiber placement
• Automated tape lay-up
• Filament winding
• Hand lay-up
• Pultrusion
• Prepreg/pre-impregnated fibers
• Resin transfer molding (RTM)
• Spray-up

Electronics:

The manufacturing process for electronic chips and circuits includes design and prototyping, as well as the fabrication and assembly of electronic components onto printed circuit boards (PCBs). Depending on the application, electronics may also include wire harnesses, which are internal “wires” within small electronics (or small casings). Cable assemblies bundle wires into a single casing (e.g., computer power outlet). Manufacturing processes for electronics include:

• Cable assembly
• PCB assembly
• PCB fabrication
• Wire harness assembly

Finishing:

Finishing is the last production process stage, and it includes the application of additional treatments, processes, or coatings to improve a product’s appearance or performance. In this phase, the product is refined to meet specific requirements, surface characteristics, and performance standards before use or sale.

Forming:

The forming process involves shaping and transforming malleable materials – such as sheet metal – into components or shapes using mechanical or thermal methods. Forming processes include:

• Bending
• Drawing
• Deep drawing
• Extrusion
• Forging
• Rolling
• Stamping

Heat & surface treatment:

Manufacturers apply heat and surface treatments to surface materials (e.g., product casings) to harden the material for increased durability. Manufacturing examples include:

• Aging, stress relief
• Anodize, black oxide
• Degreasing
• Electroplating
• Painting
• Powder coat cart
• Surface hardening
• Through hardening

Joining:

In manufacturing, joining is the process of connecting or assembling multiple components to form a single, unified structure. Joining methods include:

• Adhesive bonding
• Brazing
• Interlocking mechanisms
• Mechanical fastening (e.g., screws and rivets)
• Sealing
• Soldering
• Welding

Machining:

Machining is a manufacturing process that shapes and removes material from a workpiece to create a desired shape, size, or finish. This technique produces a wide range of precision parts and components used across consumer and industrial markets. Factories apply machining to various materials including metals, plastics, wood, and composites. Machining methods include:

• Machining of additive, cast, forged, or fabricated parts
• Milling, turning, grinding, and gear making
• Multi-spindle machining
• Stock machining

Metal fabrication:

Metal manufacturing broad covers the processes required to shape, form, and assemble metal materials to create a range of products components, assemblies, and products. This production process involves raw metals, metal alloys, or metal sheets. Processes include:

• Bar and tube
• Extrusions
• Hard and soft tooled
• Stamping and die stamping
• Sheetmetal hydroforming
• Sheetmetal roll forming
• Sheetmetal stretch forming
• Sheetmetal transfer die

Molding (moulding):

In manufacturing, molding shapes a semi-liquid or liquid material by pouring or pressing it into a mold cavity. The material cools, solidifies, or cures inside the mold and assumes the shape of the mold cavity. For additional information, please see the casting and forging and plastics manufacturing definitions on this page. Different types of molding include:

• Blow molding
• Casting
• Compression molding
• Injection molding
• Rotational molding

Plastics:

Plastic manufacturing is a multifunctional process in which plastic products and components are created using synthetic polymer materials. Standard processes involved in plastic manufacturing include:

• Blow molding
• Extrusion
• Injection molding
  • Assembly molding
  • Assembly plastic molding
• Polymerisation (polymer process)
• Reaction injection molding
• Resin production
• Rotational molding
• Structural foam molding
• SMC compression molding
• Sheet plastic
• Thermoforming

How should you evaluate the best manufacturing process for your product?

Consider these factors when selecting the most appropriate manufacturing process for your organization.

• Cost:  Estimate all costs: equipment, labor, materials, and ongoing production. And compare manufacturing costs across regions and suppliers.
• Equipment:  Evaluate technology requirements and consider design alternatives to address potential limitations regarding machines/factories available for production. And identify the need for new (or custom) machines, processes, or workforce skill requirements.
• Material Selection:  Determine suitable materials for the product based on material availability, performance, sustainability, cost, etc. And align the bill of materials (BOM) with an appropriate manufacturing process.
• Product Requirements:  Consider size, complexity, material properties, and unique features.
• Production Volume:  Estimate production volume (per production run and annual volume) and the requirement to scale production rapidly.
• Quality:  Select a manufacturer and associated process that supports compliance with industry standards (e.g., ISO 13485 compliance for medical devices).
• Risk:  Identify potential manufacturing technology factors, material availability, supply chain issues, geopolitical risks, and other potential challenges. 
• Sustainability Impact:  Evaluate and compare the environmental impact of each potential process (e.g., the CO2e impact of manufacturing cycle time and the electricity mix factor).
• Time-to-Market:  Plan for the launch date and estimate the opportunity cost of delays. Then select a manufacturer and manufacturing processes to meet your launch schedule.

Related term:  manufacturing process model