READ ALSO : NMM3540 Development of Dimensional Measurement Metrology Case Study Assignment for MSc Hand - in date: See assignment cover sheet Please read this assignment specification very carefully before beginning your work. It is also recommended that you re - read it once the report is nearing completion. Aim: This assignment requires consideration of the issues relating to the practical use of a measuring instrument and the use of metrology in a hypothetical production environment and how factor s such as measurement resolution, accuracy , equipment, environment, training, costs and time - scales , etc . have to be considered in the choice of measurement equipment and strategy for its use . The Company task : A manufacturing company produces precision components for machinery such as mining equipment and also for the railway industry . They must implement new measurement systems in a number of different areas within the company. The re is a need for increased quality and traceability to satisfy customer requirement and reduce sc rap and re - working . The company currently has a metrology room with good temperature control of +/ - 1°C which is ke pt clean . The room contains a Coordinate Measuring Machine ( CMM ) with a large working volume; however i t has limited additional inspection ca pacity available in its operation schedule. There are also two oth er areas on the shop floor that have basic inspection facilities such as steel flat plates, height gauges, callipers and indicators. These areas do not have temperature control and currently , cleanliness cannot be guaranteed, however they do have spare capacity . Measurement tasks and dimensions This section details the various components and measurements that need to be included in the Company improvement regime: 1. Analysis of captured data and appraisal of the measuring instrument . D uring the practical laboratory sessions at the beginning of the Dimensional Measurement course , you used a measuring instrument to measure a simple component. These are the items and the data that must be considered in this task. Data analysis , uncertainties , manual calculations , plots and discussions are mandatory to explain trends in the data. 2. Regular batch measurement of 20 bearing housing assemblies. Each assembly ha s 2 0 holes with diameters of 10mm, 16mm, 24mm, and 50mm . The diametrical tolerances range from +/ - 1 0µm to +/ - 4 5 µm . It is not necessary to record the actual tolerances, just know whether they are IN or OUT of tolerance. Comments on the selected equipment must be made in order to estimate its suitabilit y for long term usage. 3. Regular batch measurement of 5 long cylindrical shafts. The shafts are 800mm in length and are used in high speed rotating machinery therefore they must be straight along their length to a tolerance of +/ - 36 µm. The shaft diameter ch anges in several places to incorporate bearings etc. These distances between the shoulders also have a tolerance on the dimensions that is 1 6 µm/100mm. Data from the measurements is to be used in statistical process control charts as part of predictive main tenance strategy on certain production pr ocesses . Consider that the existing CMM capacity is limited therefore provide an alternative measuring solution (use illustrations where required to describe any bespoke measurement setup designed ) . 4. Small quantity/ 1 - offs of high value bespoke pump assemblies. The assemblies are quite complex with a r ange of features to be measured. All dimension al data needs to be recorded. Tolerances are all to the ISO standard s such as ISO 286 - 2 (1988 ). The relevant data has been extracted from the standard and attached . Your assignment: Imagine you have been appointed project manager for these tasks in the company. You must prepare a concise report outlining a suitable strategy to ensure that the stringent demands of measuring hig h quality components will be met in all respects. For measuring task 1: Provide a detailed analysis of the measured data to show the capability in terms of resolution and repeatability. Include in your discussion the procedure for using the instrument, fac tors that contribute to uncertainty and how they may be minimised or controlled. Include an appraisal on t he suitability of the measurement device , with reference to any alternatives where necessary, for inspecting small batches of components against speci fied component tolerances. For measuring tasks 2 to 4: These are new measuring tasks for the company and a strategy is required to complete them. There is scope for investment within the company to ensure that , in the long term , the company can remain a m arket leader for precision manufacturing and measurement . Care must be taken to consider cost s associated with purchasing new equipment and return on investment. Production and inspection timescales must be kept to a minimum but not at the expense of out - o f - tolerance parts reaching the customer or excessive scrap during manufacture.
