These diaphragms are used for very short stroke and are obtained by cutting flat materials: diaphragm cloth and/or elastomer sheets.
The following basic rules must be observed to avoid excessive stress and the formation of folds in the diaphragm:
- The outside and centre distances of the diaphragm fixing holes must be increased by the correction coefficient K = 0.02 DG in relation to the dimensions of the appliance.
- The diaphragm must be re-tensioned during assembly so that the fixing holes and the outside of the diaphragm match the dimensions of the device.
- The flat diaphragm must also be able to reach the extreme working positions required without straining.