IE 272 Manufacturing Processes and Operations Analysis Self Study Set 4

The following is a project proposal from an automotive manufacturer located in Ankara.

This manufacturer conducts its after-sales service processes through 32 authorized service stations spread all over Turkey. There is also a customer service department at the headquarters employing 4 technical auditors responsible for the 32 service stations. These 4 technical auditors visit the 32 service stations periodically and conduct auditing activities for both technical services and warranty parts. Technical auditors control warranty parts randomly and they evaluate whether the specified warranty procedure is implemented in a correct manner or not, they also control technical equipment used in the service stations. Each technical auditor is responsible for a set of service partners and each set constitutes a region. After each technical audit, the audited parts are collected by a third party logistics company. Of course, it is necessary to inform this third party company in advance about the timing of the visits as well as the required capacity of the truck assignment.

The company states that this problem can be handled considering the following two issues:

1) Assignment of service stations to four regions (self-formed regions not the geographical ones):

The business volume of After-Sales Services needs to be analyzed and each service station should be assigned to one of the 4 technical auditors while considering the balance of business volumes and auditors constraints.

2) Visits of the technical auditors to the service stations (route planning): Service partners should be visited on a periodical basis according to the business volumes and some business constraints while minimizing the transportation costs.

The company urges that issues such as legal requirements, workforce availability, investment and operational costs and any special regional or other requirements of a given service station should be carefully accounted for in the solution effort.

Based on this, the problem is defined as follows:

It is necessary to design a decision support system to aid in the decision making process that focuses on optimization of the audit activities. This system should determine the frequency of visits to service stations and the routes along the visits to multiple stations in such a way to keep the traveling and personnel costs low while ensuring a high quality service at all stations.

Critically evaluate this problem definition and shortly answer the following.

a) State the two most important and desirable characteristics of the problem definition. Write a single clear sentence for each to justify why you think that these are desirable characteristics.

b) State the two most important and undesirable characteristics of the problem definition. Write a single clear sentence for each to justify why you think that these are undesirable characteristics.

c) Propose a better problem definition and write at most four sentences to justify why you think your definition is good. Do not compare your definition with the existing definition.

A supplier of machined components for industrial machinery (e.g., power tools, pumps, motors, compressors) operates a factory that includes a forge shop, machine shop, and finishing department. Many of the parts produced by the company are fabricated through these three departments. Because of this, the factory is laid out as three large square rooms, arranged in-line to form a rectangle with an aspect ratio of three-to-one. Each room is 200 ft by 200 ft. The rectangle runs from north to south, with the forge shop on the south end and the finishing department on the north end. Large doors are located on the south wall for work entering the factory and on the north wall for finished products exiting the factory. For one part of particular interest here, the raw material is a steel billet that is purchased from a steel wholesale supplier. The billets arrive in pallet loads of 100 billets at the shipping and receiving department, which is a building that is 35 ft by 50 ft located 25 ft from the south wall door of the factory. The shipping and receiving department inspects the parts and sends them by forklift truck to be stored in the companys warehouse that is located in another building 500 ft away from the factory in a southerly direction. The warehouse is 200 ft by 200 ft with its entrance door on the north wall. When a production order for the part is received, a factory forklift truck is dispatched to the warehouse to retrieve the billets. The forklift truck must wait while the warehouse crew locates the billets in storage, takes a pallet out of storage using the same type of forklift truck, and delivers the pallet to the dock where it is transferred to the factory forklift. The pallet is then brought back to the factory and delivered to the forge shop. The billets must wait their turn in the production schedule before being pressed into the desired shape by one of the forge presses. From the forge shop, the parts are moved to the machine shop where they are machined on two different machine tools, a milling machine and a drill press. From the machine shop, the parts travel to the finishing department for painting and baking (to cure the paint). From the finishing department, the parts are moved back to the machine shop, where additional milling is accomplished to provide two machined metal surfaces that will mate with other components in the final product. The parts are then moved to the shipping and receiving department for shipment to the customer. (a) Develop the flow process chart and (b) flow diagram for the process, using the centroid of each department to estimate distances between departments. (c) Based on your flow process chart, what are some changes in the production process that you would recommend? (d) Develop a revised procedure for the production process, documenting your revision in the form of a new flow process chart.

The Calm Seas Cruise Ship Line wants to analyze its passenger laundry operation. A typical cruise ship of the line is 850 ft in length and has 600 passenger cabins located on four decks. For every occupied cabin during a cruise, the cabin stewards retrieve the bed linens (sheets and pillow cases) and towels (wash cloths, hand towels, and bath towels) when they make up the rooms each day. Each steward is responsible for 15 cabins. The steward separates the bed linens from the towels, putting them into two separate laundry bags. Because of the large size of each bag, the two bags are separately hand-carried to the laundry department, which is located on one of the lower decks. Depending on which deck and deck section a steward serves, the travel distance ranges from several hundred feet to more than a thousand feet, plus several flights of stairs. In the laundry department, the bags are emptied, making sure that the bed linens are not mixed with the towels during laundering. The two categories of laundry are washed separately in a large washing machine, using a different wash cycle for each category. After washing, the linens and towels are dried in tumble dryers located on the same deck about 100 ft away, and then they are folded and stacked. They are then moved in stacks to the ironing department, which is located on the deck immediately above the laundry department, where they are separated and individually ironed in large flat ironers. After ironing, they are folded and stacked. From the ironing department they are transported to either of two main storerooms, located fore and aft on one of the main passenger decks for access on the following day by the cabin stewards in making up the rooms. (a) Construct a flow process chart of the laundry operation, using the bed linens and towels as the subject material in the analysis. Estimate distances moved but ignore operation times. (b) Based on your flow process chart, what are some changes in the laundry operation that you would recommend? (c) Develop a revised procedure for the laundry operation, documenting your revision in the form of a new flow process chart.