Designed for underwater tension measurement applications, for high humidity conditions and for applications in which occasional submersion due to flooding is likely, a range of miniature, compact, low-profile load cells is now available, which can be customised to suit specific applications.
The DDEN Series of load cells from Applied Measurements measure tensile or compressive forces in underwater locations to a depth of up to 10m, although the unit can be customised to operate in even greater depths. The unit is compact over a wide capacity range. Even at the top end of the capacity rating of 50kN, the unit dimensions do not change - with a diameter of just 44mm and a length of 65mm.
The DDEN is protected to IP68 and is very robust, being constructed from stainless steel. Operating temperatures are from -20 to +80degC and measurement capacities are from 250N up to 50kN. With its low deflection and high natural frequency, the DDEN is particularly suited to cable tension monitoring, marine and offshore applications, mooring lines and material testing.
Peter Lewis, Managing Director at Applied Measurements, comments: "The DDEN Series was originally developed for a marine customer in Italy, who needed to measure the precise mooring tension of buoys in the sea as part of a wave energy research project. With a small, quick and cost-effective redesign of our existing DDE style load cell, we changed the construction to stainless steel, with the two halves locking together with a seal. Internally, the unit was further protected by back-filling with an inert waterproof gel. The electrical termination is a tough IP68 multicore cable that is connected through an IP68 cable gland in order to provide fully submersible sealing."
The company envisages a diverse range of other applications for the DDEN. Mast stays on racing yachts, for example, must be kept tuned to a very high level at all times. Also, in the water industry, underground pipes need to be cleared of any obstacles or blockages. Therefore a 'pig' is often sent down the pipe and pulled through on a line to clear the obstacles. The tension of this line is critical and so load cells are required here.
Peter Lewis continues: "We can customise the DDEN Series for specific applications, while still offering the customers the same lead time as our standard range."
The DDEN Series comes with integral male threads for in-line mounting. This enables the load cell to be mounted in a wide variety of applications where conventional load cells such as S-Beams will not fit.
Applied Measurements can supply the DDEN load cells complete with monitoring and control electronics and calibrated as a system. Other options available include non-standard sizes, spherical seating rod end bearings, female adapters and compression fittings. The DDEN comes with a three-year warranty.