POWER MEASUREMENTS

When a force is applied on a shaft, torque powers are created. This is causing rising tensions in the shaft, which causes twisting and stretching of the shaft. By measuring the stretching if the shaft’ surface, it is possible to calculate the torque on the shaft using the specifications of the shaft. DB Asset Services has the expertise and the equipment to measure on two shafts simultaneously.

Applications

Application 1: Power measurements.. By measuring the power, for example, the maximum speed of a propeller shaft can be adjusted. The best efficiency point of a pump can also be determined.

Application 2: Condition monitoring.By taking processed measurements, it can be determined that installations still achieve their optimum capacity.

Application 3: Detecting control problems. With the help of strain gauges, we can measure the shaft torque and thus signal possible control problems.

Measure alternating torque to calculate torsional vibrations, to check or to identify problems. Read more about torsional vibrations here

Graph of torq measurements

Measuring principle

 

To measure the stretching, strain gauges are glued in the 4 directions of the maximum stretching. Strain gauges have the property that the resistance changes linearly with the strain that they experience. The strain gauges are connected electrically. We call this: Bridge of Wheatstone. This method of connection has the advantage that minimal resistance changes are measured.

The strips are glued on the shaft and connected. Because the shaft rotates, no direct connection to the "fixed world" can be made. For this reason, an amplifier with a small antenna is placed on the shaft. The measured signal is then sent to a receiver. With our torque measuring device, we can measure over a very large range of shaft diameters. On every shaft (from 25 mm) we are able to measure the torque, and there is no limit in terms of maximum seize.

Usefulness of power measurements

With torque measurements, the torque in the shaft of a drive is measured. DB Asset Services provides torque measurements in drives for the following purposes:

  • Check whether an installation can still deliver its capacity. This is done by measuring the speed in addition to the torque.
  • Checking components in the shaft-line have problems.
  • Checking power / speed regulations work correctly.
  • Practical check of torsional vibration calculation.