Why cannot wedge-shaped throttle elements be installed vertically? If the on-site conditions do not permit it, how should vertical installation be adjusted?
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If asked, our plant’s original pyrolysis furnace used orifice plate differential pressure sensing for measuring pressure. Since the medium flowing through the furnace contained a large amount of impurities, these impurities often caused blockages in the pressure guiding tubes, the primary valves, and the transmitter assembly. Later, the original orifice plates were replaced with wedge-shaped throttling elements combined with dual-flange differential pressure transmitters (each wedge-shaped throttling element has 4 pressure sensing points, along with two flow meters) for measurement. However, after installation, the readings from meter A and meter B differed by nearly 10%. There were no issues with either the process medium or the transmitters. Some people claim that wedge-shaped components can only be installed horizontally, but since horizontal installation wasn’t possible on site, vertical installation was required. What should be done to resolve this issue?
Wedge flow meters cannot be installed vertically, as vertical installation leads to an increase in the differential pressure, which in turn results in large flow rate errors. When installing them vertically, it is necessary to calculate the ratio of the length of the vertical pipe to the static pressure, and also take into account the zero-point and range shifts of the differential pressure transmitter; any slight change in operating conditions can cause inaccuracies. As long as a straight pipe section is ensured for horizontal installation, there is no need to consider these factors; this is why wedge flow meters are never recommended for vertical installation. Differential pressure flow meters, on the other hand, cannot be installed vertically
Because of the blockage, it was changed to a wedge shape; then won’t the pressure lead wire in that wedge shape be blocked?
Because of the blockage, it was changed to a wedge shape; then won’t the pressure lead wire in that wedge shape be blocked?
Wedge-shaped elements are mostly installed horizontally; when installed vertically, it is necessary to calculate the pressure difference between the top and bottom and configure it for use with a flow meter
Previously it was a pressure tapping tube type; now it’s a double-flange design. Previously it used orifice plates, while now wedge-shaped elements are used, which helps to effectively prevent blockages
It’s complete nonsense. Wedge flow meters can be installed in horizontal pipelines as well as vertically.
The differential pressure being measured is already very small, and the errors are large; adding a vertical installation only increases the systematic errors. It’s a miracle if it can be used at all.