Material of magnetic flap and rotameter float
Thread Content
Is it necessary for the material of floats in devices such as magnetic flap level gauges and rotameters to be one grade higher than that of the gauge cylinder? For example, if the pipe material is 316L, should the cylinder also be made of 316L, and should a Hastelloy float be used?
Theoretically, there is no comparability, but then again, the material chosen for the cylinder is definitely determined by the process medium; therefore, the material of the float must be equal to or superior to that of the cylinder, as the float plays a crucial role
There’s no need. Generally, a magnetic flap level gauge and a rotameter made of 316 material are sufficient; a float made of 316 is also adequate. But this is a different matter when the medium has corrosion requirements.
It depends on the nature of the medium; as long as it’s sufficient. For normal operating conditions, 316 is sufficient; in corrosive environments, the choice of material depends on the specific medium
Handle each case individually; for acids like *ao acid, it’s better to use 304 rather than 316
A higher level isn’t necessary; the cylinder will work, and the float will work as well.
Correct, it seems the original poster has had to deal with the troubles caused by *AO acid quite a few times
Theoretically, an 18-8 float should work; it is also necessary to check the material grade against the corrosivity of the medium. You also need to consider the density of the medium, as it needs to float. 1. There is no need to “deliberately upgrade” the float material of a rotameter. If the density of the medium is low and there is no standard float for 18-8, then an upgrade is necessary – not only the float itself, but also the accompanying guide rod. 2. Magnetic flip plates; light hydrocarbons with a density of less than 0.5 can also be used, as well as 18-8 floats. However, these floats are thick and long, and the corresponding tubes must be of the same design. The distance from the lower flange of the level gauge to the drain outlet should be at least 450 mm (the length of the float itself), which makes drainage inconvenient. By using titanium, floaters of standard size can be obtained, and overall, the price remains more or less the same. Try to use floats of the “standard size” – it makes spare parts more readily available. As for the materials, as long as they are present on the sample, there will be a corresponding standard float.