Master of Business Administration - MBA Semester II
MB0044 – Production & Operations Management - 4 Credits
(Book ID: B1133)
Set- 1 (60 Marks)
Note: Each Question carries 10 marks. Answer all the questions.
Q1.Explain in brief the origins of Just In Time. Explain the different types of wastes that can be eliminated using JIT.
Q2.What is Value Engineering or Value Analysis? Elucidate five companies which have incorporated VE with brief explanation.
Q3.Explain different types of Quantitative models. Differentiate between work study and motion study.
Q4.What is Rapid Prototyping? Explain the difference between Automated flow line and Automated assembly line with examples.
Q5.Explain Break Even Analysis and Centre of Gravity methods. Explain Product layout and process layout with examples.
Q6.Explain Juran’s Quality Trilogy and Crosby’s absolutes of quality. List out the pillars of Total Productive Maintenance.
1. 1. Explain in brief the origins of Just in Time. Explain the different types of wastes that can be eliminated using JIT.
Ans. Just in time were developed to minimize wastage across the organization. If a firm is optimistic about the demand, then that firm increases their planned inventories. On the other hand if the demand is weak when compared to the expectations, then that firm’s unplanned inventories are high. That means companies don’t keep a lot of excess inventory, then manufacture a product as an order comes in. It is management philosophy of continuous and forced problem solving.
The seven types of wastes to be eliminated according to JIT are :
1 Over production
Over production is to manufacture products before it is actually needed. If the demand for that product decreases, the extra parts or products produced may not be useful or needed. Also over production results in high storage costs and is also difficult to detect defects. So, over productions is considered a waste.
Excess procurement or production builds up stock of materials which are not immediately use, this locking space and fund carrying heavy cost.
3 Waiting time.
Waste of time happen when goods are not moving or being processed. The operator, the machine or the part will either be not working or be worked upon. The duration is can be said to be unproductive and may create more serious consequences.
Any unnecessary movement is a waste of energy; it causes blockages, disrupting movements and delaying the flow of other items creating delays.
The people, who work, do not make a study as to how the products on which they are making are utilized and do not realize the purpose for which they are made. This lack of education will lead to waste of resources. Finally, they end up in shortage of resources when needed.
6. Defective products.
The defective products leads to a tremendous loss to the company. This is because they use up the same equipments, workmen and the time that would be used to make good products. Thus defective products use up resources and result in losses.
7. Over Processing
Some steps like unnecessary processing or production do not add value to the final output. As a results, it is waste of all the inputs that go into the process.
Q.2 What is value engineering or value analysis ? Elucidate five companies which have
incorporate VE with brief explanation.
Ans. Value of engineering (VE) or value Analysis is a methodology by which we try to find substitutes for a product or an operation.
The concept of value engineering originated during the second world war. It was developed by the General Electric corporations (GEC). Value Engineering has gained popularity due to its potential for gaining high Returns on investment (ROI). This methodology is widely used in business re-engineering, government projects, construction, assembling and machining processes, health care and environmental engineering, and many others. Value engineering process calls for a deep study of a product and the purpose for which it is used, such as the raw materials used; the processes of transformation; the equipment needed, and many others. It is also questions whether what is being used is the most appropriate and economical. This applies to all aspects of the products.
1. GENERAL ELECTICALS CORPORATION (GEC)
The concepts of value engineering originated in 1947 in General Electricals corporation (GEC) When a substitute for asbestos for flooring had to be found. Specialized dealers could provide an equally good material at a lesser price.
Initially, the practioners were the people in charge of purchasing who tried to locate substitute material which would be equally good, if not better, at a lower price. This the first and basic approach to value engineering. A the concept percolated to the manufacturing departments, engineers applied the same principles and found that, they could use alternate materials, which were cheaper giving the same performance. It was also fund that dimensions and tolerance could be altered without affecting the performance of the part or the product. The investigations took them on the path of eliminating some operations. The focus was on the value of each bit materials, each operation. This approach led to the design stage.
2. ASHOK LEYLAND.
In implementation of VA, Ashok Leyland changed gear material from phosphor bronze to a less expensive cast iron and eliminated frequent field complaint of gear seizure in trucks.
T.V. Sundaram Lyenger (TVS) Limited is one of the largest automobile distribution companies in India.
During the mid 1940 to 1960s, TVS based in Madurai was ranked as the best bus transportation system in India. It could manage to run the fleets for about 96% of the time.
TVS used the VE approach to restore the mobility of buses that had broken down. They stocked their garage with some critical assemblies of a bus. Whenever, a part or an assembly failed of a bus, they replaced it immediately with a new one, thus restoring mobility within a couple of hours.
When compared to the traditional method, this approach has gained much more benefits to the company, it helped to save time, reduce cost, efficient, quicker, and competitive.
4. MODI XEROX.
Modi Xerox designed the VE-d low cost copier 1025 ST, which uses a single tray. The advantage of new design is that it is easy to operate and the cost is also very low.
Titan watches introduced new designs adopting a strategy of innovation.
Q.3 Explain different types of quantitative models. Differentiate between work study and motion study.
Ans. There are different quantitative models.
1. LINEAR PROGRAMMING: Linear programming technique is often used for optimizing a given objective like; profit or revenue maximization, or cost outgo minimization. Distribution of the revenues is the critical issue, when there are limited resources and they have to meet competing demands.
2. TRANSPORTATION MODEL: Transportation model is concerned with goods from manufacturing centres or warehouses which have to be supplied to depots or retails outlets. The demand and supply position of the places where they are required or produced and the cost of transportation are considered in the model. We use this model to economize.
3. ASSISGNMENT MODEL: Allocating jobs or persons to machines, awarding different projects to contractors is done so that maximum returns occur or less expenses are incurred. Hence, calls for the use of this model.
4. INVENTORY CONTROL MODEL: Inventory control model considers the:
· Frequency of placing orders.
· Quantities per order considering the cost of placing an order.
· Number of pieces that are to be kept in reserve.
· Rate of consumption.
· Lead time required for the supplier.
· Cost involved in storage.
We have different models which give solutions to optimization depending upon the probabilities of consumption and supply.
5. WAITING LINE MODELS: Queues are formed when the rate of services is at a variance with the rate of arrival. They are formed when the rate of production is less at particular points compared to the previous one. Sometimes we see multiple service points and a single queue are formed for feeding them. Number of items which includes the following is studied with some special techniques.
· People to be serviced.
· Rate of service
· Type of queue discipline that is intended to be followed.
· Policy of priority
· Tolerable amounts of waitin
6. SIMULATION MODELS: Simulation models are used when we will not be able to formulate mathematical model. So, we develop a model which resembles a real life situation. Based on this pattern, we predict and plan our procurement, production, delivery and other actions.
7. PERT (PROJECT EVALUATION AND REVIEW TECHNIQUE) AND CPM (CRTICAL PATH METHOD) MODELS: When projects are undertaken with a number of activities, some happens in sequence, with gaps of weeks or months and some happens simultaneously. It is important to estimate the time required for completion of the project. A lot of coordination is needed while supplying the resources. It is also equally important to identify the bottlenecks and smoothen resources so that time schedules are maintained. Delayed completion may entail penalties. In this model, we adopt special methods to make the system.
We can say that work study is being conducted when analysis of work methods is conducted during the period when a job is done on a machine or equipment.
Method study is on studying the method currently being used and developing a new method of performing the task in a better way.
The study helps in designing the optimum work method and standardization of the work method.
Operation flow charts, motion charts, flow process charts, which are the elements of the task are studied to find the purpose of each activity, the sequences in which they are done, and the effect of these on the work.
The study enables the methods engineer to search for better methods for higher utilization of man and machine and accomplishment of higher productivity.
The study may help in changing some of them and even eliminate some of them to effect improvements.
The study gives an opportunity to the workmen to learn the process of study thus making them able to offer suggestions for improved methods.
The new method should result in saving of time, reduced motions and simpler activities.
Q.4 What is rapid prototyping ? Explain the difference between Automated flow line and Automated assembly line with examples.
Ans. Prototyping is a process by which a new product is developed in small numbers.
Prototyping is helpful to:
· Determine the suitability of the materials
· Study the various methods of manufacture
· Determine type of machinery required
· Develop techniques to overcome problems that may be encountered when full scale manufacturing is undertaken.
Prototype do meet the specification of the components that enter a product and performance can be measured on those. It helps in confirming the design and any shortcomings can be rectified at low cost. If serious defects or problems arise during manufacturing, a thorough change in design or even its replacement may be considered. Toa arrive at decisions and to make use of the advantageous stated above, it is important that the prototypes are made within the shortest possible time, Rapid prototyping facilities this.
The advanced Rapid Prototype Modelling Processes are:
Computer Aided Design (CAD)
Selective Laser Sintering (SLS)
Fused Deposition Modelling (FDM)
Lamination Object Manufacturing (LOM)
Electronic Beam Melting (EBM)
Different between Automated Flow lines and Assembly Flow line.
Q.5 Explain Break even Analysis and centre of gravity methods. Explain product layout and process layout with examples.
Ans. Break even analysis
Every manufacturing company will have three major contributors to cost;
1. Investments made for land, plant and machinery resulting in interest and depreciation.
2. Recurring expenses, which are not proportional to the quantity of production.
3. Variable costs, which are directly proportional to the quantity produced.
For our calculations, we combine the first two costs together and call them fixed costs. We call those costs that depend on the quantity of production as variable costs.
We compare the total costs for different locations on estimated amounts per annum and select whichever locations costs the least. However we will have to consider the possible variations in production levels during the foreseeable time spans and take decision.
CENTRE OF GRAVITY METHOD.
Centre of gravity method is used mainly when;
· Transportation costs, either for distribution of products or collection of materials from different suppliers is the main criterion.
· Production rates are high.
· The volume and weights of materials that have to be moved are huge.
· Time taken either to receive materials from suppliers or delivery to customers is critical.
It is better to locate the facility at such a place, which caters to the different points most optimally. The vital factor is the load, that is, number of items, or the weights that need to be moved from the central location to the existing or demanding point. We use this method when, both distance and load have to be considered for optimality in terms of costs.
Product layout is also called as production lines or assembly lines. They are designed and laid out in such a way that only few products are capable of being manufactured or assembled. Materials flow through the various facilities. These use special machines to perform specific operations to produce only one product at one time. So, companies should set different set of machines for different products. Workers perform a narrow range of activities to complete the operations on the product as it moves in a flow line. The operation times, the sequence of movements and routing procedures are highly standardized to meet production requirements which are synchronized with many such products to complete finished goods to meets demands. Using special machines and implementing standardization in operations have many advantages which are listed below:
· The skill required of the workers is low
· Supervision is minimal
· Training needs are small
Precautions to be taken are:
· Constant check on the processes needs to be performed so that quality is assured.
· Corrective measures have to be implemented to avoid rejections, since, the quantities that get manufactured will be continuous.
· Check for the behavioral of the worker. As jobs are repetitive, workers tend to be bored and lose concentration. This may affect productivity and quality.
Let us consider an examples of a stainless steel manufacturing industry, in which the operations turning, milling and drilling happen in a sequence. Testing is performed in each process to assure the quality. The items are then sent to the assembly block. The items that arrive for assembly are either bought out items or made item components from elsewhere in the plant. The final product inspection is made and send to the packing dispatch.