Rise in the curing temperature speeds up the chemical reactions of hydration and affects the early strength of concrete without any ill effect on the later strength. However a higher temperature during placing and setting, although increases the early strength, but affects adversely strength beyond about 7 days onwards. The explanation for this may be that a rapid initial hydration [...]
When two dissimilar metals are joined together at two points to form a closed loop and a temperature difference exists between the junctions, an electrical potential is set up between the junctions. Such an arrangement is known as thermocouple and is frequently used for the measurement of temperature. Measurement of temperature by a thermocouple is an important application of the [...]
Thermometric well is used to measure the temperature of gas flowing through a pipeline. A small tube called thermometric well is welded radially into the pipeline. The well is partially filled with some liquid and the thermometer is immersed into this liquid. When the temperature of the gas flowing through the pipeline is higher than the ambient temperature, the heat [...]
Most of heat treatment processes include the heating of a metal alloy at a high temperature. In order to obtain the optimum properties with many of the modern alloys, a fairly accurate control of their heat treatment temperatures is necessary. Pyrometry, or the measurement of high temperatures, is therefore, one of the most important aspects. 1. Electrical Resistance Pyrometers: These [...]