E77 – 98 Standard Test Method for Inspection and Verification of Thermometers, Calibration-temperature instrumentation, Liquid-in-glass thermometers. Inspection and Verification of Thermometers, is based on ASTM E77 − 14, Standard. Test Method . E1 Specification for ASTM Liquid-in-Glass Thermometers. Buy ASTM E() Standard Test Method for Inspection and Verification of Thermometers from SAI Global.
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Heat the thermometer again to the selected reference point on the main scale, keep it at this temperature for h. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the asstm of regulatory limitations prior to use.
In the case of diameter measurements, the bulb 7e7 other portions of the thermometer being tested should not enter the smaller of the holes ashm the ring gage see 5. We have no amendments or corrections for this standard. A number in parentheses indicates the year of last reapproval.
It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
They should be completely recalibrated every 6 to 12 months, depending upon the temperatures of usage.
In some instances total-immersion thermometers s77 be used under conditions of complete immersion. Return the thermometer to the bath, preheated to the temperature of test, and heat for 24 h.
If any portion of the stem containing mercury is exposed, the emergent mercury column correction should be determined. A superscript epsilon indicates an editorial change since the last revision or reapproval. It must be emphasized that to obtain meaningful results, the procedure adopted after the h period of heating must be identical to that used in the original calibration.
You can download and open this file to your own computer but DRM prevents opening this file on another computer, including a networked server. This standard is also available to be included in Standards Subscriptions. As the ice melts it will be necessary to drain off some of the water and add more crushed ice. The choice of a secondary standard will be governed by various factors. Improper annealing of the bulb, as determined by the bulb stability test, will result in thermometer readings rapidly changing with time and use.
Atsm the thermometer to cool as described in and then repeat the procedures described in and.
This standard is not included in any packages. More complete information on the construction and use of primary standard thermometers may be obtained from Asm SP For more stubborn separations it may be necessary to cool the bulb in dry ice to a point low enough to bring all of the liquid into the bulb itself. This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version.
As the voice of the U.
Inspection for uniformity of spacing can generally be accomplished by eye, but for greater accuracy a pair of dividers ast be used to advantage. Standards Subsctiption may be the perfect solution.
Gentle tapping of the thermometer while held upright will cause the bubbles to rise to the surface. If the f77 in the scale etchings washes out or fades, the thermometer will be difficult to read. You may delete a document from your Alert Profile at any time. The most common types of foreign matter which should be cause for rejection are r77 chips, particles of dirt or lint, oxide of mercury either red, yellow, or blackproducts of glass weathering commonly called white astmm, and stones or iron spots traceable to faulty glass fabrication.
For fractionally graduated thermometers a calibrated set of the following thermometers is recommended. By softly tapping on a soft spongy material or against the hand it usually is possible to bring the liquid together in the bulb. This keeps the viscosity of the liquid in the capillary low and aids in hastening drainage. Discard any cloudy or unsound portions.
Please first log in with a verified email before subscribing to alerts. Metal block baths and the salt and tin comparator baths, described in Appendix X1, are examples of the type of equipment that has been found to be suitable for this purpose. Its electrical resistance is determined by comparison with a standard resistor, using a potentiometer, a Kelvin-type double bridge, or a Wheatstone bridge, preferably of the Mueller type or an AC resistance bridge. Mercury, or its vapor, may be hazardous to health and corrosive to materials.
7e7 Because it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. Tapping the tube against the hand or the bulb on a soft spongy material, such as a rubber stopper, usually will bring the liquid together.
Temperatures are not measured directly with this instrument. However, these procedures s77 be applied to other liquid-in-glass thermometers. Need more than one copy? Heat the thermometer to the selected reference point on the e777 scale, maintain the temperature for at least 15 min, and determine the scale correction at this point. If such globules appear to unite and then reappear on cooling the bulb, they are indicative of oxidation of the mercury or ast presence of obstructions in the bore, and should result in rejection of the thermometer.
Discontinuities in the spacing are evidence of faulty graduating. Please first verify your email before subscribing to alerts. Last previous edition approved in as E 77 — In order that it shall be satisfactory for such use, the thermometer should meet the requirement that the ratio of resistances at the steam and ice points shall be greater than 1. Recalibration is performed as described in 6. Already Subscribed to this document.