CHAPTER of the rollers ranges from the smallest

CHAPTER 1INTRODUCTION1.1 Schaeffler EltmannSchaeffler AG was founded in the year 1946 by the brothers Wilhelm and Georg Schaeffler. Today the company is owned by Maria Elisabeth Schaeffler, Widow of the Founder and her son Georg F.W. Schaeffler. The Organization employs approximately 74000 people worldwide, spread over 180 locations.The Schaeffler Plant in Eltmann, Germany was founded in the year 1940, under the name “FAG Kugelfischer Georg Schäfer”. The entire bearing ball production was relocated from Schweinfurt to Eltmann as a measure to save it from bombing at the times of Second World War. It is in the year 1963, the production of bearing rollers was also relocated to Eltmann. In 2001, the majority shares of FAG was taken by INA Holding Schaeffler KG. Now, Schaeffler Eltmann is involved in the production of different types of bearing rollers namely, Barrel Rollers, both Symmetric and Asymmetric, Cylinder rollers and Needle rollers.Schaeffler Eltmann delivers its products to different Schaeffler Plants like Schweinfurt, Wuppertal, China, India and USA. Nearly 65% to 70% of its production are delivered to Schaeffler Schweinfurt, making them the main customer of the plant.1.2 ProductsAs mentioned above, Schaeffler Eltmann is a component supplier to other Schaeffler plants around the globe which manufactures different types of bearing rollers. On a Production Area of 31000m² and with 483 employees (as of 25.10.2017) 1600 types, out of which around 760 active types of rollers are produced. Every day, around 55 tons of raw material are turned or pressed into 400,000 rollers and then processed further. The size of the rollers ranges from the smallest roll of 7mm to the largest roll of 200mm in diameter and a maximum weight of 60kg per roll. Figure 1 shows different types of bearing rollers being manufactured at Schaeffler Eltmann plant. A) Symmetrical Barrel Roller Bearings  B) Asymmetrical Barrel Roller Bearings C) Cylindrical Roller Bearings  D) TORBFigure 1: Types of bearing rollers manufactured at Schaeffler Eltmann Plant.     1.3 BackgroundThe general processing stages used in the manufacturing of the roller bearings are divided into 3 stages. Namely, • The initial or soft machining.• Hardening.• Finishing or hard machining.Figure 2: Types of bearing rollers manufactured at Schaeffler Eltmann Plant.The Initial processing stages used are either pressing or turning. The decision regarding selecting the initial process is majorly based on the diameter of the rollers. For smaller diameter rollers Pressing operations and on the other hand for larger rollers turning operations are selected. After initial processing the rollers will be passed down to hardening process. Subsequent to hardening is the face grinding and Outer diameter grinding processes. Lastly as surface finishing processes either honing or vibratory grinding is used. Once super finishing processes are done, the rollers will be sorted based on the varying tolerances following 100% visual inspection. Finally the rollers will be packed. This thesis work is focused only on one production line i.e. NH8 (NOVA HONNEN) which has got its name from the machines being used in the line. Even though the line doesn’t work literally like a production line yet, the naming is done with the vision of achieving to that state.Figure 3 shows the process flow used in the NH8 production line. After soft machining, the rollers will be passed down to hardening process. Only some types of the rollers where the quality is critical will pass through ultrasound testing before hardening.After hardening process, the rollers will be subjected to face grinding operation where a small amount of material is grinded from the upper and lower faces of the rollers to make it suitable for processing in the following stages. Following face grinding is the finishing process where grinding of the outer diameter of the rollers takes place. Based on customer requirements, few of the types will go through forehead crown grinding process before surface finishing process. After the vibratory tumbling process, Flux process is done to inspect the cracks and material defects in the components. Finally, the parts are sorted and packed. Based on the requirement, few types will be going through the coating process, which has been outsourced.1.4 Problem Definition In order to achieve an efficient value stream, flow lines are the best approach which are not only well organized but also results in an efficient material flow through the production system. When built right, these flow lines help to reduce the WIP between the workstations and thus reducing the associated costs. In addition to the WIP, it also reduces the waiting time by producing the right product at the right time and thus resulting in increased throughput time and productivity. Furthermore it also reduces the efforts, complexity and cost related with the production planning. Schaeffler Eltmann has known the importance and advantages of the flow line as it has already built few production lines for the smaller rollers. Now they want to exploit these advantages in larger rollers section as well. So they have planned a pilot project of building a NH8 production line. However, as of now the downstream processes after hardening are functioning like an isolated islands resulting in an inefficient production system. This also demands for production planning at all stages and thus increasing the complexity of planning process. The products are travelling a longer distances from one workstation to other which are situated at different parts of the shop floor. Many a times products which are not immediately required are produced, resulting in increasing waiting time, associated WIP and other wastes. There are three face grinding machines which supplies the parts to NH8 line. However these machines are not only supplies to NH8 but also to other machines as well, thus increasing the complexity of planning these face grinding machine. By building a production line after hardening along with the dedicated face grinding machine or any other technology which could meet the desired qualitative and quantitative requirement at a reasonable expenses will help to reduce the above stated problems.