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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They are simpler to use than a primary standard thermometer with its accessory equipment, the latter being capable of an order of precision and accuracy far in excess of that attainable with liquid-in-glass thermometers. Allow to cool slowly. The most common types of foreign matter which should be cause for rejection are glass chips, particles of dirt or lint, oxide of mercury either red, yellow, or blackproducts of glass weathering commonly called white deposit, and stones or iron spots traceable to faulty glass fabrication.
If such globules appear to unite and then reappear on cooling the bulb, they are indicative of oxidation of the mercury or the presence of obstructions in the bore, and should result in rejection of the thermometer. 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.
Recalibration is performed as described in 6. This is due to the effect of increased gas pressure above the column producing a distortion of the bulb. In reading thermometers, account must be taken of the fact that the lines are of appreciable width. More complete information on the construction and use of primary standard thermometers may be obtained from NIST SP Inspect the thermometer for differences in appearance of the tested and untested sections of the scale portion.
Caution should be taken when handling mercury and mercury containing products. Rinse the ice with asttm water and shave or crush into small pieces, avoiding direct contact with the hands ast, any chemically unclean objects.
We have no amendments or corrections for this standard. Proceed to Checkout Continue Shopping. Select clear pieces of ice or ice made from distilled or pure water. Burning out, loosening, chalking, or fading of the pigment shall be cause for rejection. As the ice melts it will be necessary to drain off some of the water and add more crushed ice. Suitable types are described in Appendix X1. 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.
A slight tapping of the 4 E 77 — 98 thermometer against the palm of the hand will facilitate this joining. Strains in the glass as observed with a polarized light strain gage near enlargements in the stem or bore, or at the top of the thermometer, are detrimental. You can download and open this file to e777 own computer but DRM prevents opening this file on another computer, including a networked server.
Please first verify your email before subscribing to alerts. In some instances total-immersion thermometers may be used under conditions of complete immersion.
As the voice of the U. If a small portion of the liquid has separated at the top of the column and the thermometer is provided with an expansion chamber, the liquid usually can be joined by carefully and slowly heating the bulb until the separated portion is driven into asmt expansion chamber.
If a mercury separation is observed in the stem, several different ways are suggested for joining the columns, depending on the atsm of the thermometer and the type of separation.
It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. This standard ast not included in any packages. A number in parentheses indicates the year of last reapproval.
ASTM E77 – 98 Rpdf全文-调研报告-在线文档
Adjust the dividers to extend over 10 or 20 graduations, and successive intervals can be intercompared rapidly. Asym in the spacing are evidence of faulty graduating. Last previous edition approved in as E 77 — If the document is revised or amended, you will be notified by email. 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.
Because it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior e7 as appropriate.
ASTM E77 – 14e1
Add to Alert PDF. If natural cooling is used, the correction should be determined within 1 h. Ice points should be taken every 3 months. E777 bubbles are observed in the bulb, they can generally be removed by cooling the bulb with dry ice or other convenient coolant until all the liquid is drawn into the bulb.
e777 When the column itself follows into the chamber, the separated portion usually will join onto the main column. Standards Subscriptions from ANSI provides a money-saving, multi-user solution for accessing standards. The thickness of asrm gages should approximate the diameters of the holes to minimize errors resulting from the axis of the thermometer stem being other than normal to the plane of the gage. Inspection for uniformity of spacing can generally be accomplished by eye, but for greater accuracy a pair of dividers may be used to advantage.
No method has been discovered that will entirely prevent such displacement of the gas. Originally published as E 77 — 49 T. Total-Immersion Thermometers—In the case of general purpose total-immersion thermometers, the sensitivity of the thermometers to be tested will govern the choice of standard.
Subscription pricing is determined by: 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.
The choice of a secondary standard will be governed by various factors. It is frequently possible to join such separations by cooling the thermometer so that the separated portion as well as the main column both stand in the chamber.
In the case of diameter measurements, the bulb or other portions of the thermometer being tested should not enter the smaller of the holes in the ring gage see 5. Current edition approved Nov. If natural cooling in still air is used, determine the reference reading within 1 h.