Rubber diaphragms are flexible and airtight components which are employed to divide two chambers with variable volume and pressure.  

Cervellati manufactures three different types of diaphragms:    
-  diaphragms in 100% rubber;
-  diaphragms in rubber-coated fabric;
-   reinforced diaphragms in rubber + fabric insert which guarantee higher resistance
   to pressure and to corrosive fluids than all-rubber diaphragms.

Diaphragms advantages:        

Compared to pistons or radial seal (Fig. 1), the application of diaphragms offers the following advantages:     
- Perfect airtight seal;   
- Simple assembly;      
- Modest production tolerances and surface
  finishing;  
- No sliding and static friction; 
- Minimal hysteresis and high degree of
  sensitivity;      
- No need of lubrication.          

Diaphragms technical features:

-          All-rubber diaphragms: thicknesses starting from 0.35 mm;      
Rubber-coated fabric: thickness starting from 0.18 mm;

-          Diameters: from just a few mm to 800 mm;

-          Compounds filtered with a special filtering system;

-          Fabrics come in cotton polyester, nylon, nomex;

         -       Rubber-coated fabrics are made of:     
               - NBR + cotton-polyester;        
               - Epichloridrine + cotton-polyester;      
               - NBR + Nylon;
               - NBR + Viscose;         
               - Neoprene + Nylon;     
               - FKM + Nomex.          

Cervellati outsources the production of the employed mould from external specialized workshops equipped with: Cad-Cam / CNC Lathes / CNC Work Centres.    
For small productions, the moulds can be produced in common steel and in an economical solution.   
For medium and large productions or for particularly hard materials, the mould can be produced in special thermally-treated steels with chrome coating or nitriding. 
We offer rubber-coated fabrics for LPG and natural gas, also supplied in rolls.

Further information can be found about diaphragms in rubber-coated fabric and about reinforced diaphragms.