Gauges Without Gears Solve Problems Associated with High Vibration and Pulsation Service

Pressure gauges without gears are known as "Direct Drive" gauges.

Direct-drive pressure gauges replace the “C-shaped” bourdon tube and gears in a standard gauge with a unique helically wound bourdon. The helical bourdon is coupled directly to the shaft pointer, which is the only moving part. Fewer moving parts translates to fewer gauge problems. Regular recalibration is eliminated because there are no complex, wear-prone parts... like linkages, gears and sectors. Linearity is built-in; no span adjustment is necessary. Accuracy is maintained throughout the life of the gauge, which is much longer than standard gauges. Overpressure ratings are typically 150% of span which prevents calibration shift and the helical bourdon tube will typically withstand spikes of 500% of span without bursting. Helical bourdon tubes are typically made of Inconel, which is a highly elastic material with excellent corrosion resistance.

3D Instruments Direct Drive Vs. Liquid Filled Gauges

In many severe applications “C-shaped” pressure gauge cases are filled with a liquid to dampen their movements and increase service life. Besides adding cost to the gauge, the liquid fill causes other problems... loss of accuracy, discoloration and added maintenance difficulties. 3D applies a high viscosity silicone dampener, known as GAD, directly to the outer layers of the bourdon tube. This GAD dampens the pointer movement in severe vibration and/or pulsation based applications thereby eliminating the need for liquid fill. In most instances a standard 3D Accu-Drive Gauge will easily replace a traditional liquid filled gauge. The 3D gauge will provide longer service life and lower field maintenance costs. When compared to liquid filled gauges, 3D gauges can last as much as 10x longer in severe vibration and pulsation service. Using 3D Accu-Drive Gauges will have a dramatically favorable impact on your gauge cost of ownership!!


Process and Test Gauges

Stainless Steel Case Gauges

3D Instruments Product Guide


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