ASME B89.1.10M pdf download.DIAL INDICATORS (FOR LINEAR MEASUREMENTS).
ASME B89.1.10M is intended to provide the essential requirements for dial indicators as a basis for mutual understanding between manufacturers and consumers, Described herein are various types and groups of dial indicators used to measure a linear dimension of a variation from a reference dimension,
2 REFERENCES
CS(E) 119-45 Dial Indicators (Fot t.inear Measurements)
Publisher: Department of Commerce. 1401 Constitution Asenue NW, Washington, DC 20230
A.A-234tlB Indicator, Dial, Accessores. and Tei Set Publisher: General Services Administration. 11(00 F Street NW. Washington. IX’ 20405
MlL-l-K422D Indicators. Dial and Accessons
Publisher: National Technical Information Service (NTIS). 521(5 Port Royal Road, Springfield VA 22161
150 R463 Dial Gauges Reading in 0.01 mm. 0.001 in and 0.0001 in.
Publisher: International Organiiation for Siandardiration (ISO), I rue de Varembé. Case Postal 56, CH1211, (icnèvc. Switzcrland’Suisse
3 GLOSSARY
di,l indirator: a measuring instrument in which small displacements of a spindle or a lever arc magnitic by suitable mechanical means to a pointer rotating in front of a circular dial having a graduated scale.
trrvrofinthcatuw,: the amount by which the displayed value on a measurement device differs from the true mnpul
4 CLASSIFICATION BY TYPE
(a) Type A. Dial indicators in which thc spindle is parallel to the dial face (sec Fig. I).
C5 CREATiNG AN UNCERTAINTY BUDGET
AND CALCULATING UNCERTAINTY
The frst step in creating an uncertainly budget is to list all possible sources of uncertainty in the measurement process. Next, the uncertainty for that component is expressed as one standard uncertainty. Finally. the standard uncertainties are combined by taking the square root of the sum of their squares.
NOTE: For Type H uncertainties. standard uncertainty is an estimate of the standard dcv iat,on. For Type A uncertainties, the standard deviation is equal to the standard uncertainty, See the references cited in par-a. C3 for detailed information on computing the standard uncertainty for distributions other than normal distributions. The most common case in the following csarnplcs is when the distribution is uniform over some interval. An example of this is the case where only the MPL (maximum pesmissibk crmr of a device is known. so the actual error might he anywhere within that span. with an equal probability that tt is as any one particular value, Gage blocks within their grade tolerance, or calibrators within their stated specifcation arc examples of this. In this particuLar case, the standard uncertaint’s is estimated by disading the half-width of the distribution by the square root of three.
C5.1 Example 1: Mechanical Dial Indicator With 0.001 in, Graduations
The fist example. summarized in Table Cl, is an uncertainty budget for a mechanical dial indicator with 0.001 in. graduations and a working range of 1.000 in. It was calibrated using a micrometer-type calibrator. The calibration report for the instrument listed the MPE as 30 iin., and gave a measurement uncertainty fbr the process as 20 iin. The process was earned out in a room controlled to ±1°C.
C5.1.1 Calibration Device. The MPE of the calibration device (micrometer-based calibrator) could be up to 30 gin. It is assumed to be uniformly distributed with a half-width of’ 30 i.in.. so a divisor of 3 is used to convert this to a standard uncertainty. The stated uncertainty of the calibration (20 in.) has a normal disiribution and is the expandcd uncertainty, so a divisor of 2 is used to convcrt this value to a standard unccrtainty.
NOTE: It as assumed that this unccrlalnty came from a calihiation ccstifcate stating the expanded uncertainty in a form that comphcs sith the GUM guidelines (ace para. C3). It can he considered as a Type B unceilainay with a normal distribution.
C5.1 .2 Repeatability. Reproducibility, and Resolution. lit this example the repeatability of the indicator was determined by taking 30 separate readings at one position of the indicator. The standard deviation of this repeat test was 0.0003 in. The standard uncertainty is equal to one standard deviation from this study. This is a Type A uncertainty (see Note in pam. C5).
ASME B89.1.10M pdf download
