In many demanding industrial condition monitoring applications, there is a requirement for robust and reliable transducer systems, for example devices such as accelerometers, velocity sensors and proximity probes which need to meet the challenges. As a result of their 50 years of experience in designing and manufacturing essential monitoring sensors and systems, SENSONICS offers not only specialized condition monitoring products, but also the vital engineering and technical capability to deliver custom-designed sensors when required.
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Their wide range of LVDT (Linear Variable Differential Transformer) displacement transducers will not always meet the specific requirements of some applications and this is when their established bespoke design services make a big difference. Whether for a new application, replacing an obsolete product, or your existing supplier cannot meet your needs, Sensonics has the technical expertise to deliver a cost-effective solution. We can guide you through the options within our standard range with customization for a form fit and function match or develop a new design from scratch.
Let’s Take a Look at the Most Common Applications
Taking linear measurements using LVDT displacement transducers on large steam turbines to measure the movement of the turbine pedestals on the cylinder sole plates. This is a relatively easy measurement to make which requires an LVDT mounted on the turbine and an extension rod fixed or sprung onto the slides. When the turbine is coming up to temperature it expands, which can cause one side of the sliders to stick, whilst the other side continues. If this occurs the difference in the displacement output from LVDTs mounted on either side of the machine will increase to the point of creating an alarm in the control room. This is because the turbine is “crabbing” and therefore requires an engineer to be deployed to free the sticking pedestal from its slider plate, ensuring more efficient and effective maintenance.
Other Applications Which will Benefit from LVDT’s?
There are many other uses for LVDT’s in addition to the issues of thermal expansion. For example, movement of structures, such as bridges, tunnels, buildings and dams to detect deformation or crack monitoring. LVDT’s are also used as valve or actuator position feedback transducer where the signal feedback is sent to the turbine control system so that it knows how far a valve is open or closed. These can be retrofitted on bracketry across the fixed and moving part of a steam valve or in conjunction with the OEM as a high-pressure resistant design internally within the actuator.
The principles of operation of LVDT’s means they can be configured in a variety of housings depending on the degree of mechanical protection required and the use of rod end bearings, linear rolling element bearing and flexible conduit helps them to withstand the most severe environments. Sensonics also offer signal conditioning units for their LVDTs that provide oscillator and demodular functionality. Options include; the DN8032 DIN rail mount signal conditioning unit, the DC8042 die cast enclosure conditioning unit and the Sentry G3 API 670 standard compliant ultimate machine protection system.