Delft University of Technology
Faculty Mechanical, Maritime and Materials Engineering Transport Technology
R. Gratama Test results from the pipe conveyor test rig.
Internship, Report 2005.TL.6930, Transport Engineering and Logistics.
Pipe conveyor systems have been applied for more than twenty years, but still there are no worked out design standards for designing a pipe conveyor. To find out more about the design parameters of pipe conveyor systems, Conveyor Knowledge Information Technology Pty. Ltd (Ckit) in Johannesburg decided to build a pipe conveyor test rig. The working principle of this test rig is presented in this report. In September 2004, some tests have been carried out with the test rig. The first question was if the test rig would meet its requirements for testing pipe conveyor belts. The second question concerns the suitability of a specific belt for its application in a pipe conveyor system in India. During the tests, two issues were investigated: firstly the behavior of the belt when going through a curve with a radius of 300 meters; the rate of deflection of the belt was measured, as well as the circumference and the part of the belt touching the bottom dier. The second issue concerns the forces acting on the idlers keeping the belt in place; these forces are measured with help of strain gauges. To simulate a real life situation, the tension in the belt was increased up to 55 tons. Increasing the tension in the belt is done in small steps, in order to get a reasonable amount of test data.
For the belt behavior, the following test results were observed:
The deflections of the belt during the tests all stayed within the limits that were stated in advance.
The circumference of the belt showed a small decrease during the entire test program, but it always stayed within the described limits.
The part of the belt touching the bottom idler did not show a significant change at all; at most of the tests there was a small increase, but at some tests it even showed a small decrease. There was no structural increase of the part touching the bottom idler.
Measuring the forces acting on the idlers showed the following results: The forces acting on the idiers were significantly lower than expected.
The tests did not show an explicable relationship between the forces acting on the idlers and the radius of the curve of the belt. The tests did not show an explicable relationship between the forces acting on the idlers and the amount of tension in the belt.
The condusions to the tests are that the behavior of the belt was satisfying during the entire test program. It never exceeded the limits stated in advance. This belt is suitable for its application in the pipe conveyor system in India.
The forces on the idlers measured during the tests were quite different from what was expected, based on the calculations. It may not be concluded that the forces measured during the test program are the ones that are really acting on the idlers in the test rig. More research is needed to adjust the test rig for measuring the forces acting on the idlers.
The test resuits led to the following recommendations:
Ckit's easy release systems for the idler brackets should be installed in the test rig, in order to make it easier to measure the forces acting on the idlers.
To simulate a real life situation better, the test rig should be transformed into a dynamic system. A detailed checklist of what to measure should be available before starting the measurements.
Stronger strain gauge brackets should be installed in the test rig. The ones used during the test program were too weak. Reports on Transport Engineering and Logistics (in Dutch)
