Electricity and Control January 2024

MEASUREMENT + INSTRUMENTATION : PRODUCTS + SERVICES

Pressure monitoring for tempering machines

Temperature plays a significant role in many product manufacturing processes. Where a tempering machine is used, this is a permanently installed device that is responsible, as an integral component of a production plant, for tempering a mould or chosen tool in the manu facturing process. The consistent temperature of the tool or mould is a critical factor in the quality of the finished product. Water or oil is most commonly used as a medium for transport ing heat, but other fluids can also be used, depending on the application. Tempering machines often serve both a heating and a cooling function. The medium is brought to a specific temperature and added to the process through a system of pipes. There, the medium transfers the heat or cold as energy. This can then go back to the tempering machine in a closed circuit to top up the used energy once more. The purpose of a tempering machine is to provide the manufacturing process with the desired temperature and to keep this constant. Temperature sensors are used to check the target temperature. Keller, which is locally represented by Instrotech, re cently supplied a PR-21Y piezoresistive pressure trans mitter to a client specialising in developing and produc ing oil and water tempering machines. The Keller 21Y transmitters are used to ensure pressure monitoring on the tank of the tempering machine. An overpressure, which can result from the heating of the medium, can be prevented with the help of pressure monitoring. A con stant pressure of 16 bar is set. The transmitters from the Y range are particularly suitable because they have a very low temperature error range. Keller’s 21Y piezoresistive pressure sensor is weld AMETEK Land, a leading manufacturer of highly accu rate infrared pyrometers, scanners, and thermal imagers, has introduced an industry-leading protection design for thermal imaging cameras without the compromise of a wire grid. This new, proven, protective housing has been de veloped for thermal cameras in challenging installation conditions and offers distinct benefits in terms of optical clarity, temperature accuracy, improved efficiency and lower maintenance. Thermal imaging camera housings have to meet im pact test requirements, so a wire grid or mesh is typically installed in front of a germanium window, which acts as a protective layer to absorb and disperse impact energy. Germanium windows are impermeable to ultravio let and visible light, so, to the naked eye, they have a dark, metallic appearance. In the infrared range, germa nium has an excellent, broad transmission range from 2 to 16 μm, which makes it ideal for mid-wave-infrared

Above: KELLER recently supplied PR-21Y piezoresistive pressure transmitters to a client that specialises in developing and producing oil and water tempering machines.

Right: The KELLER 21Y piezoresistive pressure sensor. ed, fully insulated and encapsu lated with no internal seals. Its ro bust stainless steel housing and compact design make it suitable for space-critical industrial applica tions, heat pumps, air conditioning technology, and the food industry. The 21Y’s direct analogue signal path with high bandwidth guaran tees high, long-term stability.

For more information visit: www.instrotech.co.za

Thermal imaging cameras without wire grid protection

(MWIR) and long-wave-infrared (LWIR) applications. LAND’s protective housing uses a germanium win dow, but without an additional wire grid, and it still meets the Exd impact test requirement. It also reduces expo sure to high temperatures and corrosive, outdoor envi ronments, and ensures the thermal imaging camera is not a potential source of ignition. James Cross, Global Industry Manager for Hydrocarbon Processing Industries at AMETEK Land, said: “Using the grid-less concept on several installations, the AMETEK Land LWIR in EXSH housing provides LAND’s crystal-clear images

AMETEK Land’s EXSH without a wire grid still meets the Exd impact test requirement.

with highly accurate, sensitive, repeatable temperature data. Users increasingly demand higher accuracy temperature values to achieve better yields, improved efficiency, and longer maintenance intervals, and we expect the demand for gridless housing designs to increase with that.” □

JANUARY 2024 Electricity + Control

17