- freely available
Metals 2019, 9(4), 466; https://doi.org/10.3390/met9040466
- The size of the holes in the valve plate influences the total efficiency of the gerotor. It can be increased with a very basic mechanical operation, such as drilling. Total efficiency was increased on average by 5% when we tested a hole size of 6.3 mm instead of a hole size of 5.5 mm (original size).
- Very promising tribological behavior was observed when the steel/DLC contact was tested in water. It was proven that the friction of the steel/DLC contact in water (0.065) was lower than the friction of the steel/DLC contact in oil (0.075). The wear loss of the discs was very low and, in some cases, almost unmeasurable.
- Surface analysis showed that there were almost no defects on worn surfaces, and this was in good agreement with the calculated wear coefficient.
- The original hydraulic motor, where all mechanical parts were made from steel, did not operate when water was used as the working fluid.
- DLC was deposited onto the floating outer ring, so steel/DLC contacts were formed within the hydraulic motor between (a) the floating outer ring/the inner rotor, (b) the floating outer ring/the gerotor housing, and (c) the floating outer ring/the valve plate. Such a modified hydraulic motor achieved a total efficiency of up to 23%.
Conflicts of Interest
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|Rectangular Distribution (%)||Triangular Distribution (%)|
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