A friend in a food industry is asking advise regarding a mass flow sensor suitable for a tomato concentrate line. It seems that standard flow rate sensors are not reliable as the medium is not of constant density and may contain significant amounts of air. The pipe diameters are around 15 mm, medium temperature is 95 degrees C and nominal mass flow rate is 6 - 15 kg/min. The output signal is required to control the filling of containers (at 0.4 kg) at a minimum accuracy of 0.5 percent . The only mass flow sensors I have found up to now are very expensive for a small plant. Perhaps someone can provide some advise regarding possible solutions and suppliers. Regards Martin Cutajar

 

Micro Motion has introduced a new competitive priced Mass Flow meter. I'll be using my first 3 in April. Roderick K. Duet

 

>It seems that standard > flow rate sensors are not reliable as the >medium is not of constant density and may >contain significant amounts of air. You are right, inconsistent density and air in the pipes will cause problems. But it depends on the accuracy you need, which you didn't mention. You can discuss this problem with www.rheonik.de which I found the cheapest but the most accurate mass flowmeters (because they are only producing these). If you cannot solve it with them, you have to change your process allowing for a weighing system. You can collect the juice in a small tank and measure the weight of it, for example. Hakan Ozevin