Metrology and SPC Laboratory

Metrology and SPC Laboratory - ME 120 Metrology and SPC...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
ME 120 Metrology and SPC Laboratory MSPC-1 Metrology and SPC Pre - lab Questions 1. What is the resolution of the Ultra-Cal III electronic caliper? 2. What is the accuracy of the Ultra-Cal III electronic caliper? 3. What is the repeatability of the Ultra-Cal III electronic caliper? 4. What is the difference between accuracy, resolution, and repeatability? Purpose To introduce fundamental concepts in metrology and statistical process control To familiarize students with common metrology tools, such as dial calipers and coordinate measurement machines Learning Objectives Upon completion of the laboratory, the student will be able to: use a caliper properly so as to make repeatable single-point measurements on physical artifacts to within the stated accuracy and resolution of the caliper interface a caliper via RS232 cable and operate software to enable measurement data to be recorded via computer explain the limitations of single point measurements in assessing the geometry of physical artifacts gather measurement data and manipulate it to produce an X bar and R chart for assessing statistical process control assess whether or not a process in “in control” or “out of control” given data from X bar and R charts Components Qty. Item 1 Fowler Ultra-Cal III electronic caliper, 6 in. (cat. no. 54-100-333) 1 Simplex RS232 connection kit (cat. no. 54-100-333) 1 PC with Microsoft Excel (or equivalent spreadsheet software) 1 Centerless ground pin kit Introduction Metrology The ability to measure physical quantities, such as length, time, force, etc. is of fundamental importance in everyday life, and especially in engineering, manufacturing, and science. The science of measurement is called ‘metrology’. Of particular importance to the mechanical engineer is dimensional metrology, which addresses processes for determining he SJSU Department of Mechanical and Aerospace Engineering Metrology and SPC Experiment 17DEC05
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
ME 120 Metrology and SPC Laboratory MSPC-2 linear and angular quantities of machine parts or their features [Farago, 1994]. In order for products to function properly, their component parts must meet dimensional requirements as specified on engineering drawings. One of the most common dimensional or geometric characteristics is that of ‘size’. We say that a feature of a part has size when, for every point on the feature, there exists an opposed point on the feature and these opposed point pairs have collinear opposed unit normal vectors [Tandler, 2001]. A unit normal vector is a vector of length one unit (inches, miles, microns, whatever) that is perpendicular to a surface. For example, consider the drawing of a cylindrical pin shown in Figure 1. Pick any point on the cylindrical surface, and there will be an opposed point on the cylindrical surface that has a collinear opposed unit normal vector, e.g., points A and B below. A feature with size is denoted on an engineering drawing with a double-ended arrow and a nominal dimension (and sometimes a tolerance).
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 09/08/2010 for the course ME 120 at San Jose State University .

Page1 / 8

Metrology and SPC Laboratory - ME 120 Metrology and SPC...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online