This device is used for measuring temperature due to its accuracy and the fact that it does not require any other equipment except the human eye. The lig thermometer is one of the earliest thermometers. Media in category liquid inglass thermometers the following 125 files are in this category, out of 125 total. The cylindrical bulb of a typical laboratory thermometer is about 3 mm in diameter and 12 mm long. What liquidinglass thermometers have high resolution and high accuracy. Glass thermometers with a safe alternative for mercury. The more liquid there is, the more liquid will expand and rise in the glass tube. Maximum thermometer a medical mercuryinglass maximum thermometer showing the temperature of 38. A glass thermometer containing mercury that indicates the temperature being measured.
Mercuryinglass thermometer franks hospital workshop. Sp scienceware offers astm and astm like liquidinglass thermometers with high resolution and accuracy. Looking for eversafe liquid in glass thermometer, temp. Nist traceable calibration 2 4 point liquid in glass. What makes a liquidinglass thermometer sensitive to a small. To calibrate create a scale a thermometer we need known upper and lower fixed points such as the steam point at 100 c and the ice point at 0 c. A procedure for the effective recalibration of liquidinglass. Liquid in glass thermometer free download as powerpoint presentation. Galileo is credited with inventing the thermometer, circa 1592. Liquidfilled thermometer article about liquidfilled. A liquidinglass thermometer is widely used due to its accuracy for the temperature range 200 to 600c.
Us epa, office of pollution prevention and toxics, national program chemicals division. A procedure for the effective recalibration of liquid inglass thermometers author. They are more accurate than many other thermometer types in common use, although they tend to be less convenient for many applications. Individually serialized to enable nist traceability. Some properties of substances used to determine changes in temperature include changes in dimensions, electrical resistance, state, type. Essentially, the galileo thermometer operates on the principle. Figure 1 principle features of liquidinglass thermometers. Two reversible adiabatics cannot intersect duration. Oiml draft recommendations and documents are devel. Liquidinglass thermometers 1 applies only to the french text. May 10, 2012 well, there are two design features which make it sensitive. Compared to other thermometers, it is simple and no other equipment beyond the human eye is required. The temperature t indicated by the thermometer is the mercury temperature which will only equal t f under equilibrium conditions. Nationalbureauofstandards division221,section01 marked.
The measurement accuracy depends on the depth of immersion of the thermometer in the medium to be measured. It gives fairly accurate results within the temperature range of 200 toconstructionmain featuresapplicationsadvantageslimitations. You should walk away with not only an appreciation for the wide range of temperature measuring instruments available, but also a sense of the limitations of each. Each thermometer is also individually serialized and packaged. An example of the liquid in glass thermometer is the mercury thermometer which been in use since. Liquidinglass industrial thermometer reotemp instruments. Liquidinglass thermometry even though the liquidinglass thermometer is used much less frequently today than formerly, it is still a very commonly used device. Liquidinglass thermometer calibration service resolve a doi. Jan 30, 2018 the liquid in glass thermometer how it works duration. Astm nonmercury liquidinglass thermometer alternatives epa.
Fisherbrand general purpose liquidinglass partial immersion. The liquidinglass thermometer is intended for temperature measurement using thermal expansion of a liquid as a suitable property. Instructionsexplaininghowtosubmit a thermometer to thenational bureau of standards forcalibration areprovided, and thetechniques and equipment,such asstirredliquid comparison baths, used in the calibration proceduresare. Wise instituteforbasicstandards nationalbureauofstandards washington,d. The alcohol thermometer or spirit thermometer is an alternative to the mercury in glass thermometer and has similar functions. Thermcos precision liquid in glass thermometers are manufactured with the finest glass manufactured under iso2001 guidelines. Pdf a liquidinglass lig thermometer uses the thermal expansion of a liquid as the thermometric property.
A liquid filled thermometer should be immersed up to a reference scale division or a specially applied line on the scale partialimmersion thermometer. Astm liquid in glass thermometers novatech international. For this reason, liquid thermometers have a reservoir to increase the amount of liquid in the thermometer. Comparable in accuracy to mercury filled thermometers, but are 100% environmentally safe accurate temperature reading without sample contamination is achieved by using the filled bottle included, which mimics the sample insert the thermometer into the bottle and place near the samples for. Unlike the mercury in glass thermometer, the contents of an alcohol thermometer are less toxic and will evaporate quickly. Choose a glass thermometer by the length that will be immersed in the liquid or gas. Liquid in glass astm temperature thermometers are designed for specific applications by astm, but may also be used for other testing methods where the temperature ranges, subdivisions, and immersions are appropriate. A liquid in glass thermometer is a glass capillary tube having a liquid filled bulb present at one end. Liquidinglass thermometer calibration service unt digital library. Not sure how the same thermometer could be calibrated ok in 2011 but this year the high temp point was not within calibration.
Small changes in temperature cause the bulb to expand and contract, pushing the liquid up through the tube. Nowadays, the triple point of water is used instead the triple point occurs at 273. In our glass thermometer range we have included multipacks designed for the medical profession which represent exceptional value. A need to know, for specific application, what the thermometer is reading to a high. To confuse the issue further, there are several test standards which call for the use of a liquid in glass thermometer to be used incorrectly. It is employed in technology, laboratory practice and medicine to measure temperatures from 200 to 750c. Liquid in glass thermometer principle the liquid in glass thermometer, is the most commonly used device to measure temperature and it is inexpensive to make and easy to use. Partial immersion thermometers are immersed in the fluid to the specified immersion depth. Regulations such as iso 9000 require reports of calibration for thermometers. Standard operating procedure temperature, thermometer. Report discussing important elements of thermometer design.
Our glass thermometers conform to the international temperature scale of 1990 its90. When the hollow sphere was heated, the air inside it expanded and bubbled through the liquid at. Whats a galileo thermometer and how do you read it. Although it is normally an instrument of only moderate accuracy, the very best of them, when used with sufficient attention to detail, have. A procedure for the effective recalibration of liquidin. A liquidinglass thermometer measures temperature based on the thermal expansion of mercury or spirit alcohol in a glass container. In these cases, it is important to use the thermometer as described in the test procedure, even if it is technically incorrect. Glass thermometer an overview sciencedirect topics. Astm nonmercury liquidinglass thermometer alternatives. A thermometer is a device that measures temperature or a temperature gradient. The measuring sensitivity of liquidinglass thermometers increases with the amount of liquid in the thermometer. Astm nonmercury liquid in glass thermometer alternatives author.
Inner top of body threaded to take thermometer adapter or vacuum adapter. A liquidinglass thermometer consists of a glass sometimes quartz bulb with a glass capillary joined. The liquid in glass thermometer has a glass bulb attached to a sealed glass tube also called the stem or capillary tube. Liquidinglass thermometers chipkin automation systems. Fisherbrand general purpose liquidinglass partial immersion thermometers are ideal for use in chemical laboratories, universities, scientific institutions, food and beverage processing, petrochemical laboratories and the pharmaceutical industry.
The nist certificates for the master thermometers should be kept on file for. Calibration of liquidinglass thermometers page 12 unt. Thus, although temperature cannot be measured directly, its effects can be measured. Unfollow thermometer glass replacement to stop getting updates on your ebay feed. International oiml r 3 recommendation edition 2002 e.
Pdf emergent liquid column corrections for liquidinglass. Mercuryinglass thermometer 2 these points are adequate for approximate calibration but both vary with atmospheric pressure. The liquid in glass thermometer how it works duration. A procedure for the effective recalibration of liquid in glass thermometers. Each glass ball has a metal tag attached that serves to both indicate temperature and as a counterweight. I let them know i had questions on my evaluation but to date, no contact from the company. The thermometer the solid in question is a mercury in glass thermometer that is immersed in a liquid. It has been used in medicine, metrology and industry. May 05, 2015 the measurement of temperature a change in temperature of a substance can often result in a change in one or more of its physical properties.
It is one of the oldest thermometers available in the industry. Scribd is the worlds largest social reading and publishing site. Glass thermometers are inexpensive and portable making them ideal to store at home as part of your home first aid kit. The liquid thermometer is a very simple mechanism that requires only the human eye to read, and so it sees widespread use. There are several types of thermometer including the mercuryinglass or the alcoholinglass thermometer, shown in the diagram below. Even though the liquidinglass thermometer is used much less frequently today than formerly, it is still a very commonly used. Often times, this scale contains an ice point reference that can be used for calibration. Thermometer adapter has threaded cap with port to take thermometer, glass tubing or similar objects, up to 6. Liquid in glass thermometer principle instrumentation tools. In an open container filled with colored alcohol, he suspended a long narrowthroated glass tube whose end was shaped into a hollow sphere sort of like an upsidedown thermometer. Central bore in body permits passage of thermometer, gases, etc. Manual of petroleum measurement standards chapter 7. A need to know how accurately a thermometer is reading or if it is still accurate to specifications. Liquid in glass thermometer thermometer mercury element.