{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

# labmanual - MAE 2381 RELEASE5 1 Metrology Dimensional...

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

M A E 2 3 8 1 R E L E A S E 5 9 / 1 / 2 0 0 8 1 Metrology* Dimensional measurements and uncertainty analysis The aim of this laboratory is to familiarize students with several geometrical measuring instruments and determine their accuracies, limitations, and capabilities. Note: This lab does not require a diagram of data flow for Lap prep. What you will learn 1. Principles of linear measurement 2. Uncertainty analysis 3. Elements of report writing 4. Introduction to instrument characteristics Equipment you need 1. Steel Rule 2. Vernier caliper 3. Micrometer caliper 4. Micrometer depth gauge 5. Manufactured “pin” for inspection Procedure In this lab, we will use instruments using the inch scale only. 1. Equipment List: Note down manufacturer’s name, serial and model numbers (if present) of all the instruments and the sample pin, so as to able to identify them precisely, including the specimen pin (select only one and use that particular one throughout this lab), the steel ruler, the Vernier caliper, the micrometer caliper and the micrometer depth gauge (refer to Figure 1.4). If no identification number is present, write down what is available. 2. Estimate the resolution (least count) accuracy of each of the provided measuring devices and record these values in your laboratory notebook. Verify the following. Steel Ruler (0.01 inch) Vernier Calipers (0.001 inch) (VC) Micrometer Calipers (0.001 inch) (MC) Micrometer Depth Gauge (0.001 inch) (MDG) For VC, MC, MDG, you will see that each inch is divided into 10 decimals, each decimal is divided into 4 quarters and each quarter is divided into 25 subdivisions, on the Vernier Scale on the VC or the circular scale in MC and MDG. So, 1 in./10/4/25 = 1/1000 inch. *Adapted from D. D. Seath, MAE 2181 Laboratory Manual, The University of Texas at Arlington, 1998 3. Note down the maximum reading of each instrument. Verify the following: steel ruler (6 in.), Vernier calipers (~5.2 in.), micrometer calipers (1.05 in.) and the micrometer depth gauge (1 in.). 4. Note down the zero error, if any of, all four instruments. What is zero error? If your car is sitting in the parking lot and the speedometer reads 5 mph, then the speedometer has a zero error of 5 mph. In this case, you have to subtract 5 every time you read the gauge. Similarly, for every analog instrument, one has to check for zero

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

View Full Document
M A E 2 3 8 1 R E L E A S E 5 9 / 1 / 2 0 0 8 error before using it. In the event that an instrument has a zero error (negative or positive), one has to add or subtract that value from each reading. 5. Using each of the available instruments, make multiple measurements (at least 5) of each “pin” dimension shown in Figure 1.5. Record all values in your laboratory datasheet in a neat table similar to Table 1. Note : Not all of the available instruments will be appropriate for measuring each pin dimension. For example, it would be incorrect to measure the inner diameter of the “pin” (dimension “B” in Figure 1.2) using the micrometer depth gauge. Why? If you deem a particular measurement with a given instrument unnecessary, simply skip it and note the decision (and reasoning) in your laboratory datasheet.
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 84

labmanual - MAE 2381 RELEASE5 1 Metrology Dimensional...

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

View Full Document
Ask a homework question - tutors are online