Opma exam 2 Ch. 6
Little's Law
Inventory = throughput rate x flow time
A firm that makes predesigned products directly to fill customer orders has this type of production environment.
Make-to-order
This is a production layout where similar products are made. Typically, it is scheduled on an as-needed basis in response to current customer demand.
Manufacturing cell
The relationship between how different layout structures are best suited depending on volume and product variety characteristics is depicted using this type of graph.
Product-process matrix
Why is it that reducing the number of moves, delays, and storages in a manufacturing process is a good thing? Can they be completely eliminated?
Reduces the number of moves saving time Reduces unnecessary delays and creates confidence among the clients helps in reducing costs of inventory These can not be eliminated completely
Reducing Task Time Requirements
Split the task Share the task Use parallel workstations Use a more skilled worker Work overtime Redesign
Manufacturing cell
a dedicated area where products that are similar in processing requirements are produced
Workstation cycle time
a uniform time interval in which a moving conveyor passes a series of workstations Also the time between successive units coming off the line
Continuous process
assembly line only the flow is continuous such as with liquids
assembly line balancing
assigning tasks to a series of workstations so that the required cycle time is met and idle time is minimized
What does the product-process matrix tell us? How should the kitchen of a Chinese restaurant be structured?
it is a model that is used to demonstrate the combination of a product's volume and various characteristics, together with the nature of the processes that make it Typically, a Chinese restaurant is customer oriented and will be high on output. therefore, a Chinese restaurant will be high on a product process matrix. However, as information given, it should be structured as a continuous process
days of supply
the number of days of business operations that can be supported with the inventory on hand
Precedence Relationship
the order in which tasks must be performed in the assembly process
Lean manufacturing
the production of goods using less of everything compared to mass production To achieve high customer service with minimum levels of inventory investment.
Assembly Line Design
-workstation cycle time -assembly line balancing -precedence relationship
If a production process makes a unit every two hours and it takes 42 hours for the unit to go through the entire process, then the expected work-in-process is equal to this.
21 units = 42/2
A firm is using an assembly line and needs to produce 500 units during an eight-hour day. What is the required cycle time in seconds?
57.6 seconds = (8 × 60 × 60)/500
A finished goods inventory contains, on average, 10,000 units. Demand averages 1,500 units per week. Given that the process runs 50 weeks a year, what is the expected inventory turn for the inventory? Assume that each item held in inventory is valued at about the same amount.
7.5 turns = (1,500 × 50)/10,000
What is the efficiency of an assembly line that has 25 workers and a cycle time of 45 seconds? Each unit produced on the line has 16 minutes of work that needs to be completed based on a time study completed by engineers at the factory.
85% = (16 × 60)/(25 × 45)
What's the relationship between the design of a manufacturing process and the firm's strategic competitive dimensions
A firm's strategic competitive dimension determines the type of manufacturing process it would follow
What is meant by a process? Describe its important features.
A manufacturing process is a combination of sub processes involved in the production of products. a product is made by sourcing the raw materials/components, produced or the manufactured by the facility, and finally delivering the product to the consumer Manufacturing environments are mainly classified based on the positioning of the customer order decoupling point.
Days-of-supply
A measure of the number of days of supply of an item.
What is a customer order decoupling point? Why is it important?
A point where the inventory is positioned to allow the production process to operate independently of the customer order delivery process A correct position of this point is necessary as the inventory is placed at this point, and this position controls the manufacturing strategy, where the final assembly is done, as well as the waiting time of the customer for the product.
Assemble-to-order
A primary task is to define a customer's order in terms of alternative components since these are carried in inventory An example is the way Dell Computer makes their desktop computers
Make-to-stock
A production environment where the customer is served "on-demand" from finished goods inventory. Essential issue in satisfying customers is to balance the level of inventory against the level of customer service Examples of products Televisions Clothing Packaged food products
Make-to-order
A production environment where the product is built directly from raw materials and components in response to a specific customer order.
Inventory turn
An efficiency measure where the cost of goods sold is divided by the total average value of inventory.
process flow
Any process is comprised of a set of tasks needed to be performed to product output. It includes material, man, and information flow.
A point where inventory is positioned to allow the production process to operate independently of the customer order delivery process.
Customer order decoupling point
Production Process Mapping
Develop a high-level map of a supply chain process Useful to understand how material flows and where inventory is held First step in analyzing the flow of material through a production process
A firm that designs and builds products from scratch according to customer specifications would have this type of production environment.
Engineer-to-order
Project layout
For large or massive products produced in a specific location, labor, material, and equipment are moved to the product rather than vice versa. The product remains in a fixed location A high degree of task ordering is common A project layout may be developed by arranging materials according, to their assembly priority
Engineer-to-order
Here the firm works with the customer to design the product, which is then made from purchased material, parts, and components
What is meant by manufacturing process flow?
In a manufacturing process, material and information must move throughout the facility between manufacturing points and storage locations. The path that both material and information take as they move through the facility defines the process flow.
Throughput
The average rate (e.g., units/day) that items flow through a process.
What is the objective of assembly-line balancing? How would you deal with the situation where one worker, although trying hard, is 20 percent slower than the other 10 people on the line?
The objective is to create an efficient balance between the tasks and workstations to minimize idle time. If the employee is deemed valuable, training may enhance his/her speed. It is also possible to place him/her in the "choice" job. meaning that workstation which has the most idle time to adjust for slowness.
How does the production volume affect the selection of a process and profitability?
The production volume and the cost or process associated with producing such volume will result in the profit or loss in the process of the firm. According to demand, if demand for a product increases or decreases, the firm will change the product volume.
Flow time
The time it takes one unit to completely flow through a process.
Inventory measures
Total average value of inventory Inventory turn Days of supply
Total average value of inventory
the sum of the value (at cost) of the raw material, work-in process, and finished goods inventory Commonly tracked in accounting systems and reported in financial statements
Workcenter
to arrange workcenters in a way that optimizes the movement of material Optimal placement often means placing workcenters with high levels of interdepartmental traffic adjacent to each other
Customer order decoupling point
where inventory is positioned to allow entities in the supply chain to operate independently
Assembly line
work processes are arranged according to the progressive steps by which the product is made
