Cellular manufacturing — Lean Manufacturing and Six Sigma Definitions

Manufacturing cells are sets of machines that are grouped by the products or parts that they produce. This type of system is used in the cellular manufacturing concept and is distinct from the traditional functional manufacturing system, which groups all similar machines together. The use of manufacturing cells is generally used to increase the flow of materials and to eliminate waste in the manufacturing process.

CELLULAR MANUFACTURING

Some of the benefits of lean manufacturing can include reduced lead times, reduced operating costs and improved product quality. Cell production is an important ingredient of lean manufacturing and refers to a manufacturing system where the workforce is divided into self-contained teams designed to complete a particular manufacturing process or product. The team is responsible for quality control and ‘sells’ the part-finished product to the next cell which is regarded as an ‘internal customer’.

Work in Progress vs. Work in Process: What’s the Difference?

These systems use lasers, electron beams or thermal print heads to melt or partially melt ultra-fine layers of material in a three-dimensional space. The PBF process creates a physical object from a digital design or CAD file. In all of GE Additive’s machines the process involve the spreading of the metal powder layer by layer and uses either a laser or electron beam to melt and fuse powder together to create a part. Loose or unfused powder is removed during post processing and is recycled for the next build.

The resulting reduction in time and handling ultimately provides a reduction in processing costs. Some firms utilize “linked-cell manufacturing,” which is the concept of arranging the manufacturing cells near the assembly cells. Hopefully, the floor layout will also provide for the easy flow of a product to shipping, if shipping is located close to the cells in a streamlined flow.

What is a cell in lean manufacturing?

In a cell, all operations that are necessary to produce a product or service for a customer are performed in close proximity, often times in a U-shaped layout, thus allowing for quick feedback between operations when problems and other issues arise.

This information guides the path of a nozzle or print head as it precisely deposits material upon the preceding layer. Or, a laser or electron beam selectively melts or partially melts in a bed of powdered material. As materials cool or are cured, they fuse together to form a three-dimensional object. Lean manufacturing is a methodology that focuses on minimizing waste within manufacturing systems while simultaneously maximizing productivity. Waste is seen as anything that customers do not believe adds value and are not willing to pay for.

A flexible manufacturing system (FMS) can improve efficiency and thus lower a company’s production cost. Flexible manufacturing also can be a key component of a make-to-order strategy that allows customers to customize the products they want.

Create flow.Eliminate functional barriers and identify ways to improve lead time. This aids in ensuring the processes are smooth from the time an order is received through to delivery. Lean manufacturing relies on preventing interruptions in the production process and enabling a harmonized and integrated set of processes in which activities move in a constant stream.

The use of robots in the production segment of manufacturing industries promises a variety of benefits ranging from high utilization to high volume of productivity. Each Robotic cell or node will be located along a material handling system such as a conveyor or automatic guided vehicle. The production of each part or work-piece will require a different combination of manufacturing nodes. The movement of parts from one node to another is done through the material handling system. At the end of part processing, the finished parts will be routed to an automatic inspection node, and subsequently unloaded from the Flexible Manufacturing System.

  • Companies are able to respond to changing customer desires with high variety, high quality, low cost, and with very fast throughput times.

Material flow distance is low in cellular manufacturing because every parts travel only in a small area (cell). By efficient layout design of machines in each cell, 30 to 70% reduction in material flow distance can be achieved. With DMLM, a laser completely melts each layer of metal powder while EBM uses high-power electron beams to melt the metal powder.

FOCUSED CELLULAR MANUFACTURING

The ultimate goal is to provide perfect value to the customer through a perfect value creation process that has zero waste. To accomplish this, lean thinking changes the focus of management from optimizing separate technologies, assets, and vertical departments to optimizing the flow of products and services.

As its name implies, additive manufacturing adds material to create an object. By contrast, when you create an object by traditional means, it is often necessary to remove material through milling, machining, carving, shaping or other means.

A flexible manufacturing system (FMS) is a production method that is designed to easily adapt to changes in the type and quantity of the product being manufactured. Machines and computerized systems can be configured to manufacture a variety of parts and handle changing levels of production. Sometimes referred to as the Toyota Way, the TPS’ main objectives are to design out overburden and inconsistency and to eliminate waste. Waste not only refers to materials, but time, such as consumer time waiting for product or assistance and even waste of movement. The philosophy also relies on the process being as flexible as possible to reduce stress, which counts as overburden and generates waste.

The value stream is the totality of the product’s entire life-cycle from the raw materials through to the customer’s use of, and eventual disposal of, the product. In order to eliminate waste, the ultimate goal of Lean, there must be an accurate and complete understanding of the value stream. Steps, materials, features, and movement that do not add value are eliminated. According to Womack and Jones, value stream mapping will almost always reveal three types of muda. There is no end to the process of reducing effort, time, space, cost, and mistakes.

This is done through entire value streams that flow horizontally across technologies, assets, and departments to customers. The term “additive manufacturing” references technologies that grow three-dimensional objects one superfine layer at a time. Each successive layer bonds to the preceding layer of melted or partially melted material. It is possible to use different substances for layering material, including metal powder, thermoplastics, ceramics, composites, glass and even edibles like chocolate. Additive manufacturing uses data computer-aided-design (CAD) software or 3D object scanners to direct hardware to deposit material, layer upon layer, in precise geometric shapes.

What is meant by cellular manufacturing?

Cellular manufacturing is a manufacturing process that produces families of parts within a single line or cell of machines operated by machinists who work only within the line or cell. A cell is a small scale, clearly-defined production unit within a larger factory.

A variety of ceramics have also been used in additive manufacturing, including zirconia, alumina and tricalcium phosphate. Also, alternate layers of powdered glass and adhesive are baked together to create entirely new classes of glass products. Additive manufacturing, also known as 3D printing, is a process that creates a physical object from a digital design. Learn more about the process of additive manufacturing in this short video. Objects are digitally defined by computer-aided-design (CAD) software that is used to create .stl files that essentially “slice” the object into ultra-thin layers.

Understanding Manufacturing Cells

Companies are able to respond to changing customer desires with high variety, high quality, low cost, and with very fast throughput times. Material flow distance is defined as total distance travelled by all parts/materials to manufacture a single product or a variety of different products. By reducing it we can significantly reduce total manufacturing cost & time.

The lean principle of pull helps ensure flow by making sure that nothing is made ahead of time, building up work-in-process inventory and stopping the synchronized flow. Rather than using the traditional American manufacturing approach of pushing work through based on a forecast and schedule, the pull approach dictates that nothing is made until the customer orders it. This requires a great deal of flexibility and short design to delivery cycle times. It also requires an efficient way of communicating what is needed to each step in the value chain.

Simply, lean means creating more value for customers with fewer resources. A lean organization understands customer value and focuses its key processes to continuously increase it.

Also, return to the first step and begin the next lean transformation, offering a product which is ever more nearly what the customer wants. Perfection is the complete elimination of waste so that all activities create value for the customer.

Cellular Manufacturing is a lean manufacturing approach that helps companies build a variety of products for their customers with as little waste as possible. In cellular manufacturing, equipment and workstations are arranged in a sequence that supports a smooth flow of materials and components through the process, with minimal transport or delay. The optimal layout is one that minimizes the distance between cells, or the distance to the next production point.