The growing need for temperature calibration
June 2009
Temperature Measurement
No thermometer will remain entirely consistent in its indication. Thermometers and sensors such as Mercury-in-glass (MIG), thermocouples (T/C), thermistors, resistance thermometers (RTDs) change their characteristics with time and temperature cycling – and they can become contaminated. This means that all thermometers need to be characterised or calibrated. There is a need to calibrate to meet quality standards, and in medical and safety applications this may be vital to safeguard life. Often real savings can be achieved simply by accurately determining a thermometer’s characteristics.
There are three levels of temperature calibration:
* Primary laboratories – these are often National Laboratories, now known as National Metrology Institutes, NMIs.
* Secondary laboratories – so called because they do not maintain 'Primary Standards'. These labs generally calibrate thermometers against standards in comparison baths.
* Industrial calibration – here temperature indicators are often calibrated with electrical simulators which are connected to the instruments sensor input. The device can then be rapidly checked by programming the equivalent 'temperature' input into the indicator.
Heat sources
Note that the temperature sensors themselves have the potential for significant drift, so it is important to test and calibrate these sensors using a heat source.
There is a wide variety of heat sources for industrial calibration, the most popular being dry block calibrators. These are able to provide temperatures ranging from 65°C below ambient up to 1200°C. More recently multipurpose sources and liquid baths have become increasingly popular.
The Isocal-6 range of products from Isotech is believed to be unique, as it can be used in six different ways. As standard the units can be used as dry block calibrators with a removable metal block drilled to accept temperature sensors. The block can be removed and replaced with a tank of liquid which is stirred as it is heated or cooled. Other accessories allow it to be used to calibrate surface sensors and infrared thermometers.
For more information contact Lenton Laboratory & Scientific Equipment, +27 (0)11 476 4662, [email protected], www.lenton.co.za
Further reading:
Noncontact infrared temperature control in aluminium rolling process
Instrotech
Temperature Measurement
The aluminium rolling process is critical to the aluminium manufacturing industry, where precise temperature measurement is essential for ensuring high-quality product output and protecting equipment. The Optris long-wavelength camera can accurately measure strip temperatures in cold rolling and coiling applications.
Read more...
Where simplicity meets reliability
Endress+Hauser South Africa
Temperature Measurement
The new iTEMP TMT31 temperature transmitter from Endress+Hauser combines simplified selection, ordering, installation and operation with the highest reliability and long-term stability in one product.
Read more...
Automating car window defrosters
Temperature Measurement
Window defrosters are vital features in vehicles, particularly in colder climates. The automotive manufacturer seeks an efficient solution to quickly and precisely measure the temperature of the windows, ensuring that the connections, installed cables and wires work correctly and have no defects before the vehicle’s final release.
Read more...
The impact of thermal imaging in steam methane reformers
Temperature Measurement
As global demand for hydrogen, ammonia and fertilisers increases, LAND is empowering steam methane reformer operators to unlock efficiency gains at existing plants to meet ambitious production targets while also safely decarbonising.
Read more...
Proven indicators monitored in three dimensions
ifm - South Africa
Temperature Measurement
The VVB30x continuously detects vibrations in three measurement axes and uses them to calculate proven indicators for evaluating machine condition.
Read more...
Digital display electronic sensors
Transducer Technology
Temperature Measurement
The Trantech TTED series is a versatile range of digital display sensors designed for high-accuracy measurement of pressure, flow and temperature.
Read more...
Quality process control instrumentation
Instrotech
Temperature Measurement
Instrotech is a leading provider of high-quality process control instrumentation and industrial automation solutions that are designed to optimise efficiency, reliability and safety across industries.
Read more...
Three ways to conduct thermal inspections
Comtest
Temperature Measurement
There’s no universal solution for all infrared inspections with a Fluke thermal camera, also known as a thermal imager. You need to match your method to the type of equipment you’re inspecting and the level of detail you require.
Read more...
Modern N1020 temperature controller
Temperature Measurement
Temperature control is a fundamental aspect of maintaining the integrity and quality of products in industries such as food processing, pharmaceuticals and healthcare. The N1020 temperature controller, designed for precision and reliability, addresses the stringent requirements of these sectors by offering advanced features and robust functionality.
Read more...
Safer, simpler temperature measurement
ABB South Africa
Temperature Measurement
ABB has launched an enhanced version of its NINVA TSP341-N non-invasive temperature sensor, delivering safer and simpler temperature measurements for applications in the chemical, oil and gas industries.
Read more...
printer friendly version