Flow Computation

ZM-Calc:

ZM-Calc helps sizing of low pressure reducers or back pressure relief valves based on required maximum flow rate. The maximum flow rate results from the highest possible level change (filling gradient or discharging gradient) and, in addition, from possible weather influences in case of non-insulated outdoor tanks or containers etc.

Low Pressure Reducer (LPR, ZM-R):

In this case, the single discharging gradient of the tank or container (e.g. the single pump draining output) is used. An additional value for a possible drop in temperature is added for non-insulated outdoor applications. The program can also calculate this value.

Back pressure relief valves (LPS, ZM-B):

In this case, the single filling gradient of the tank or container (e.g. the single pump filling output) is used. An additional value for a possible rise in temperature is added for non-insulated outdoor containers. The program can also calculate this value. On basis of this data, ZM-Calc calculates a respective flow coefficient (a valve seat size), which is sufficient in any case. No further margin must be added. In case of doubt, please contact us.
Comments:
If ZM-Calc is not used, a first approach to sizing of the respective devices may be based on twice the filling or discharging gradient and compared to the corresponding data sheets. In case of doubt, please contact u

P-controller:

P-controllers may be used for gases as well as liquids. The flow is calculated with a margin of approx. 20% in relation to the theoretical flow value according to the data sheet. Please consult us for sizing in each case if pressure differential is lower than 3bar.