Ch 7 - Manufacturing Processes Flashcards
WHAT ARE MANUFACTURING PROCESSES?
Manufacturing processes are used to make everything that we buy ranging from the apartment building in which we live to the ink pens with which we write.
The high-level view of what is required to make something can be divided into three simple steps, which are they?
- sourcing the parts we need
- actually making the item
- sending the item to the customer
a supply chain view of this may involve a complex series of players where subcontractors feed suppliers, suppliers feed manufacturing plants, manufacturing plants feed warehouses, and finally warehouses feed retailers. Depending on the item being produced, the supply chain can be very long with subcontractors and manufacturing plants spread out over the globe (such as an automobile or computer manufacturer) or short where parts are sourced and the product is made locally (such as a house builder).
these activities are organized to minimize cost while meeting the competitive priorities necessary to attract customer orders.
What is lead time?
The time needed to respond to a customer order.
What is the customer order decoupling point?
A key concept in manufacturing processes is the customer order decoupling point which determines where inventory is positioned to allow processes or entities in the supply chain to operate independently.
Selection of decoupling points is a strategic decision that determines customer lead times and can greatly impact inventory investment. The closer this point is to the customer, the quicker the customer can be served.
What is the essential issue in satisfying customers in the make-to-stock environment?
The essential issue in satisfying customers in the make-to-stock environment is to balance the level of finished inventory against the level of service to the customer.
Examples of products produced by these firms include televisions, clothing, and packaged food products. Providing more inventory increases costs, so a trade-off between the costs of the inventory and the level of customer service must be made. Many make-to-stock firms invest in lean manufacturing programs in order to achieve higher service levels for a given inventory investment.
What is lean manu?
To achieve high customer service with minimum levels of inventory investment.
Process selection refers to the strategic decision of selecting which kind of production processes to use to produce a product or provide a service. The format by which a facility is arranged is defined by the general pattern of workflow; there are five basic structures, which are they?
- Project layout - A setup in which the product remains at one location, and equipment is moved to the product. In developing a project layout, visualize the product as the hub of a wheel, with materials and equipment arranged concentrically around the production point in the order of use and movement difficulty.
- Workcenter - Often referred to as a job shop, a process structure suited for low-volume production of a great variety of nonstandard products. Workcenters sometimes are referred to as departments and are focused on a particular type of operation. such as all drilling machines in one area and all stamping machines in another. The most common approach to developing this type of layout is to arrange workcenters in a way that optimizes the movement of material.
- Manufacturing cell - Dedicated area where a group of similar products are produced. Manufacturing cells are widely used in metal fabricating, computer chip manufacture, and assembly work.
- Assembly line - A setup in which an item is produced through a fixed sequence of workstations, designed to achieve a specific production rate. The path for each part is, in effect, a straight line. Discrete products are made by moving from workstation to workstation at a controlled rate, following the sequence needed to build the product. Examples include the assembly of toys, appliances, and automobiles. These are typically used in high-volume items where the specialized process can be justified.
- Continuous process - A process that converts raw materials into finished product in one contiguous process. Such structures are usually highly automated and, in effect, constitute one integrated “machine” that may operate 24 hours a day to avoid expensive shutdowns and startups. Conversion and processing of undifferentiated materials such as petroleum, chemicals, and drugs are good examples.
The choice of which specific equipment to use in a process often can be based on an analysis of cost trade-offs. What is the standard approach to choosing among alternative processes or equipment?
There is often a trade-off between more and less specialized equipment. Less specialized equipment is referred to as “general-purpose,” meaning it can be used easily in many different ways if it is set up in the proper manner. More specialized equipment, referred to as “special-purpose,”. The trade-offs involve the cost of the equipment (the manual drill is inexpensive, and the drill press expensive), the setup time (the manual drill is quick, while the drill press takes some time), and the time per unit (the manual drill is slow, and the drill press quick).
A break-even chart visually presents alternative profits and losses due to the number of units produced or sold. The choice obviously depends on anticipated demand.
What is Manufacturing process flow design ?
It is is a method to evaluate the specific processes that raw materials, parts, and subassemblies follow as they move through the plant. The most common production management tools used in planning and designing the process flow are assembly drawings, assembly charts, route sheets, and flow process charts.
What is a process flow chart?
A process flowchart denotes what happens to the product as it progresses through the productive facility. The focus in analyzing a manufacturing operation should be the identification of activities that can be minimized or eliminated, such as movement and storage within the process.
What does a process usually consist of?
A process usually consists of (1) a set of tasks, (2) a flow of material and information that connects the set of tasks, and (3) storage of material and information.
- Each task in a process accomplishes, to a certain degree, the transformation of input into the desired output.
- The flow in a process consists of material flow, as well as flow of information. The flow of material transfers a product from one task to the next task. The flow of information helps in determining how much of the transformation has been done in the previous task and what exactly remains to be completed in the present task.
- When neither a task is being performed nor a part is being transferred, the part has to be stored. Goods in storage, waiting to be processed by the next task, are often called work-in-process inventory.
What does a process analysis involve?
Process analysis involves adjusting the capacities and balance among different parts of the process to maximize output or minimize the costs with available resources.
Potential sequencial solution to a process analysis?
a. Determine the capacity (number of components produced per week) of the entire
process. Are the capacities of all the processes balanced?
b. If the molding process were to use 10 machines instead of 6, and no changes were to be made in the final assembly task, what would be the capacity of the entire process?
c. If our company went to a second shift of eight more hours on the assembly task, what would be the new capacity?
d. Determine the cost per unit output when the capacity is (1) 6,000 per week or (2)10,000 per week.
